prostaglandin-d2 and Hypersensitivity

Current research suggests that the prostaglandin D

Topics: Asthma; Humans; Hypersensitivity; Immunity, Innate; Lymphocytes; Prostaglandin D2; Receptors, Prostaglandin

Topics: Amyloid beta-Peptides; Animals; Crystallography, X-Ray; Drug Design; Humans; Hypersensitivity; Inflammation; Intramolecular Oxidoreductases; Lipocalins; Molecular Chaperones; Muscular Dystrophies; Pain; Piperidines; Prostaglandin D2; Protein Conformation; Sleep

Immunological activation of mast cells is an important trigger in the cascade of inflammatory events leading to the manifestation of allergic diseases. Pharmacological studies using the recently discovered DP(1) and CRTH2 antagonists combined with genetic analysis support the view that these receptors have a pivotal role in mediating aspects of allergic diseases that are resistant to current therapy. This Review focuses on the emerging roles that DP(1) and CRTH2 (also known as DP(2)) have in acute and chronic aspects of allergic diseases and proposes that, rather than having opposing actions, these receptors have complementary roles in the initiation and maintenance of the allergy state. We also discuss recent progress in the discovery and development of selective antagonists of these receptors.

Topics: Animals; Asthma; Humans; Hypersensitivity; Prostaglandin Antagonists; Prostaglandin D2; Receptors, Immunologic; Receptors, Prostaglandin

Topics: Dinoprostone; Epoprostenol; Humans; Hypersensitivity; Prostaglandin D2; Prostaglandins

Allergic inflammations feature an accumulation of T helper 2 (Th2) cells, eosinophils, and basophils into the inflamed sites and are often triggered by antigen-IgE mediated activation of mast cells that secret a variety of mediators. Therefore, the mast cell is known as a conductor cell in allergic inflammations. Prostaglandin (PG) D(2) is the major prostanoid secreted from the activated mast cell and has long been implicated in allergic diseases. The involvement of PGD(2) in allergic inflammation has been corroborated by several studies. Two PGD(2) receptors are known as the DP receptor and CRTH2. CRTH2 differs from DP in its signal pathways: CRTH2 is coupled with Gi-type G protein and DP is coupled with Gs-type G protein. It was reported that DP-deficient mice subjected to ovalbumin-induced asthma model systems showed suppressed allergic reactions. Functions of CRTH2 in vivo have not been clear, but CRTH2 mediates PGD(2)-dependent cell migration and the activation of Th2 cells, eosinophils, and basophils. Therefore, the CRTH2 signal seems to promote allergic disease. The findings from these in vivo and vitro studies suggest that PGD(2) secreted from activated mast cells may be involved in the formation and/or maintenance of allergic inflammations through its dual receptor systems.

Topics: Animals; Humans; Hypersensitivity; Mice; Prostaglandin D2; Receptors, Immunologic; Receptors, Prostaglandin

Prostaglandin (PG) D(2), the major cyclooxygenase metabolite generated from immunologically stimulated mast cells, is thought to contribute to the pathogenesis of allergic diseases due to its various inflammatory effects. However, the lack of PGD(2) (DP) receptor antagonists has limited the study of its essential roles in the disease state. Recent discoveries of several DP receptor antagonists, the development of the mutant mouse and the discovery of a second PGD(2) receptor, CRTH2 (chemoattractant receptor-homologous molecule expressed on Th2 cells) receptor, have revealed the crucial roles of PGD(2) and CRTH2 receptors in allergic disorders. This review presents biological evidence that PGD(2) plays an essential role in allergy disorders and discusses the therapeutic possibilities of recently reported PGD(2) antagonists.

Topics: Animals; Anti-Allergic Agents; Humans; Hypersensitivity; Ligands; Prostaglandin D2; Receptors, Immunologic; Receptors, Prostaglandin; Structure-Activity Relationship

Allergic inflammation is orchestrated by mainly antigen-specific CD4+ T cells, eosinophils and mast cells, which is a characteristic feature of bronchial asthma, rhinitis and atopic dermatitis. Prostanoids are one of the arachidonic metabolites, which are produced by a variety of inflammatory cells upon stimulation and are thought to be involved in the pathogenesis of diseases as well as the regulation of homeostasis. We investigated the role of a prostanoid, prostaglandin D2 (PGD2), in the pathogenesis of allergic bronchial asthma using its receptor, DP, gene-deficient mice. We found that the disruption of the DP gene attenuated the allergen-induced airway eosinophilic inflammation, Th2 type cytokine production and bronchial hyperresponsiveness to cholinergic stimuli, suggesting that PGD2 is an important mediator of allergic asthma. In contrast, the treatment of non-steroidal anti-inflammatory agents, which are known to be inhibitors of cyclooxygenases, did not inhibit or instead exaggerated these responses in asthmatics or experimental animal models, indicating that there are regulatory prostanoids in allergic inflammation. Recently, strategies of gene manipulation such as the "knockout" or "transgenic" techniques are important means to understand the role of a certain functional molecule. These approaches and the development of their antagonists/inhibitors could help us to understand the function of prostanoids in the pathophysiology of allergic disorders.

Topics: Animals; Asthma; Bronchial Hyperreactivity; Cytokines; Humans; Hypersensitivity; Hypersensitivity, Immediate; Inflammation; Mast Cells; Prostaglandin D2; Prostaglandins

During allergic disease, leucocytes infiltrate the affected tissues and release their mediators and cytokines. In this way, the local inflammatory process is induced and maintained. Basophilic granulocytes have been demonstrated in lung and sputum of allergic asthmatics, in nasal mucosa and secretion of allergic rhinitis patients, and in skin lesions of atopic dermatitis patients. The number of basophils correlates with the severity of the disease. Analysis of mediator profiles and cellular contents of lavages of nose, skin and lung during allergic late-phase reactions (LPR) have demonstrated histamine, but not tryptase or prostaglandin D2. The histamine-containing cells have been characterized as basophilic granulocytes. This indicates that infiltrating basophils but not mast cells are activated and release their inflammatory contents in the LPR. We are interested in the cellular mechanisms that determine the degranulation of basophils during LPR. Basophil activators, such as allergens and activated complement, are not present at these sites. However, cytokines that prime basophils but do not induce degranulation, such as interleukin-5 (IL-5) and granulocyte/macrophage colony-stimulating factor (GM-CSF), have been detected at sites of LPR. We have now observed that after emptying intracellular Ca2+ stores by means of the Ca2+ adenosine triphosphatase (ATPase) inhibitor, thapsigargin, basophils become extremely sensitive to stimuli that do not affect the Ca2+ stores themselves but that induce degranulation, such as the phorbolester, phorbol myristate acetate (PMA). The most interesting finding was that although both thapsigargin and IL-3, IL-5 or GM-CSF do not induce basophil degranulation by themselves, a 2 min preincubation of basophils with thapsigargin followed by addition of one of these cytokines resulted in extensive histamine release: IL-3 induced 71 +/- 7% histamine release (conc1/2max 6 pM), IL-5 induced 43 +/- 8% histamine release (conc1/2max 41 pM) and GM-CSF induced 57 +/- 10% histamine release (conc1/2max 140 pM). Interestingly, the effect of thapsigargin could be mimicked by platelet-activating factor (PAF) (range 10(-9) to 10(-6) M), although to a lesser extent. Our results indicate that basophil degranulation in tissues during late-phase reactions might be caused by a combination of mediators or cytokines depleting Ca2+ stores, as platelet-activating factor or thapsigargin do, concurrent with activation by interleukin-3, interleukin-5 or

Topics: Asthma; Basophils; Bronchoalveolar Lavage Fluid; Calcium; Cell Degranulation; Chymases; Complement C5a; Cytokines; Granulocyte-Macrophage Colony-Stimulating Factor; Histamine; Histamine Release; Humans; Hypersensitivity; Interleukin-3; Interleukin-5; N-Formylmethionine Leucyl-Phenylalanine; Nasal Lavage Fluid; Phorbol Esters; Platelet Activating Factor; Prostaglandin D2; Receptors, IgE; Serine Endopeptidases; Skin; Tetradecanoylphorbol Acetate; Thapsigargin; Tryptases

Topics: Antigens; Asthma; Bronchi; Histamine Release; Humans; Hypersensitivity; Inflammation; Mast Cells; Prostaglandin D2; Prostaglandins D; Pulmonary Ventilation; Time Factors

Topics: Animals; Arachidonic Acids; Arthritis, Rheumatoid; Edema; Eosinophils; Guinea Pigs; Humans; Hypersensitivity; Leukotriene B4; Mast Cells; Mice; Muscle Contraction; Nephritis; Prostaglandin D2; Prostaglandins; Prostaglandins D; Rabbits; Rats; Receptors, Fc; Receptors, IgE; Receptors, Immunologic; SRS-A; Thromboxanes

The dose-response (dose, 0.01, 0.05, 0.1, 0.5, 1, and 5 mg) profiles of 10 atopic and 10 nonatopic subjects were determined for nasal patency, secretion weight, pulmonary function, eustachian tube function, middle-ear function, and symptoms after intranasal inhalation challenges with histamine, bradykinin, methacholine, prostaglandin D2, and prostaglandin F2 alpha (PGF2 alpha). Results demonstrated that challenge with PGF2 alpha increased nasal patency, whereas challenge with all other substances decreased patency. The relationship between substances in eliciting a nasal congestive response was prostaglandin D2 greater than histamine greater than bradykinin greater than methacholine. A similar effect ordering was noted for the postchallenge development of eustachian tube dysfunction. Secretion weights were significantly greater after challenge with histamine compared to all other substances. A decrease in pulmonary function was observed only after challenge with PGF2 alpha, although the effect was not statistically significant. No changes in middle-ear pressure were observed for challenges with any of the substances. Only histamine challenge provoked sneezing, whereas challenge with either of the prostaglandins provoked cough. With the exception of methacholine, all substances caused symptoms of rhinorrhea, congestion, and sore throat. Bradykinin was particularly effective in provoking "pain/pressure"-related symptoms. With the exception of secretion weight, the differences between responses of atopic and nonatopic subjects were not statistically significant. These results document mediator specificity in the physiologic and symptomatic responses to intranasal challenge.

Topics: Adolescent; Adult; Bradykinin; Dinoprost; Dose-Response Relationship, Drug; Ear; Forced Expiratory Volume; Histamine; Humans; Hypersensitivity; Male; Methacholine Chloride; Nasal Mucosa; Nasal Provocation Tests; Prostaglandin D2; Pulmonary Ventilation; Reference Values; Rhinitis

The effect of systemic glucocorticoid treatment on early- and late-phase nasal allergic reactions after allergen challenge was determined in a double-blind, cross-over study in 13 allergic individuals. The subjects were pretreated for 2 d before challenge with 60 mg prednisone per day or a matching placebo. A previously described model using repeated nasal lavages for measuring mediator release in vivo was utilized. Symptom scores obtained repeatedly before, during, and after the challenge and the number and timing of sneezes were recorded. The mediators measured were histamine. N-alpha-p-tosyl-L-arginine methyl ester (TAME)-esterase activity, kinins, PGD2, and LTC4/D4. Albumin was also measured as a marker of plasma transudation. Blood samples were taken for determination of total number of white blood cells, differential count, and total blood histamine content. No effect of steroid therapy was found on the appearance of symptoms or any of the mediators, except a reduction in kinins, in the early phase of the allergic reaction. However, in the late phase, the prednisone reduced the number of sneezes (P less than 0.01), as well as the level of histamine (P less than 0.05), TAME-esterase activity (P less than 0.05), kinins (P less than 0.05), and albumin (P less than 0.05). Only low levels of leukotrienes were found in the late phase, but the quantities of these mediators seemed to be decreased by the glucocorticoid treatment (P = 0.06). PGD2 did not increase during the LPR and thus was not affected by glucocorticosteroids. The immediate response to a second challenge 11 h after the first was also evaluated. Whereas the appearance of mediators was enhanced over the initial response to the same challenge dose in placebo-treated subjects, this enhancement was abrogated after prednisone treatment. As this dose of drug is known to be clinically effective in treating hay fever, the present study confirms the earlier findings of others that short-term systemic glucocorticoid treatment inhibits the late phase but not the immediate phase of antigen challenge. Furthermore, secondary enhancement of immediate responses is inhibited. This study shows that glucocorticoids inhibit the generation or release of inflammatory mediators during the late reaction and the physiologic response.

Topics: Administration, Intranasal; Aerosols; Chromatography, High Pressure Liquid; Double-Blind Method; Histamine; Histamine Release; Humans; Hypersensitivity; Kinins; Leukocyte Count; Nasal Mucosa; Peptide Hydrolases; Pollen; Prednisone; Prostaglandin D2; Prostaglandins D; Random Allocation; Serum Albumin; Sneezing; SRS-A

Topics: Allergens; Humans; Hypersensitivity; Prostaglandin D2

Group 2 innate lymphoid cells (ILC2s) are rare innate immune cells that accumulate in tissues during allergy and helminth infection, performing critical effector functions that drive type 2 inflammation. ILC2s express ST2, the receptor for the cytokine IL-33, and chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2), a receptor for the bioactive lipid prostaglandin D

Topics: Adoptive Transfer; Animals; Cell Movement; Cell Proliferation; Cells, Cultured; Disease Models, Animal; Female; Humans; Hypersensitivity; Immunity, Innate; Interleukin-33; Lung; Lymphocytes; Mice; Mice, Knockout; Nippostrongylus; Primary Cell Culture; Prostaglandin D2; Receptors, Immunologic; Receptors, Prostaglandin; Recombinant Proteins; Strongylida Infections

Group 2 innate lymphoid cells (ILC2s) play a key role in the initiation and maintenance of type 2 immune responses. The prostaglandin (PG) D. We set out to examine PG production in human ILC2s and the implications of such endogenous production on ILC2 function.. The effects of the COX-1/2 inhibitor flurbiprofen, the hematopoietic prostaglandin D

Topics: Anti-Allergic Agents; Carbazoles; Carbonic Anhydrase Inhibitors; Cell Communication; Cells, Cultured; Cytokines; Flurbiprofen; Humans; Hypersensitivity; Intramolecular Oxidoreductases; Lipocalins; Lymphocyte Activation; Lymphocytes; Prostaglandin D2; Receptors, Immunologic; Receptors, Prostaglandin; Sulfonamides; Th2 Cells

Topics: Animals; Anti-Inflammatory Agents; Arachidonate 12-Lipoxygenase; Arachidonate 15-Lipoxygenase; Asthma; Dexamethasone; Dinoprostone; Disease Models, Animal; Fatty Acids, Omega-3; Humans; Hypersensitivity; Inflammation; Mice; Mice, Inbred C57BL; Mice, Knockout; Prostaglandin D2; Respiratory Hypersensitivity

Human type-2 CD8

Topics: A549 Cells; Asthma; CD8-Positive T-Lymphocytes; Cell Line, Tumor; Chemokines; Cytokines; Humans; Hypersensitivity; Inflammation; Leukotriene E4; Lipids; Lymphocyte Count; Mast Cells; Prostaglandin D2; Pulmonary Eosinophilia; Th2 Cells

iNKT cells and mast cells have both been implicated in the syndrome of allergic asthma through their activation-induced release of Th2 type cytokines and secretion of histamine and other mediators, respectively, which can promote airways hyperresponsiveness (AHR) to agents such as methacholine. However, a mechanistic link between iNKT cells and mast cell recruitment or activation has never been explored. Our objective was to determine whether iNKT cells are necessary for the recruitment of mast cells and if iNKT cells can influence the acute allergen induced bronchoconstriction (AIB) caused by mast cell mediator release. To do so, we pharmacologically eliminated iNKT cells using a specific antibody (NKT-14) and examined its impact on airway inflammation and physiological phenotype. In mice treated with NKT-14, the elimination of iNKT cells was sufficient to prevent AHR and pulmonary eosinophilic inflammation elicited by administration of the iNKT cell agonist αGalCer. In mice treated with NKT-14 and then sensitized and challenged with house dust mite extract (HDM), eliminating the iNKT cells significantly reduced both AHR and AIB but did not affect pulmonary inflammation, the mast cell population, nor the release of the mast cell mediators mast cell protease-1 and prostaglandin D2. We conclude that while iNKT cells contribute to the phenotype of allergic airways disease through the manifestation of AIB and AHR, their presence is not required for mast cell recruitment and activation, or to generate the characteristic inflammatory response subsequent to allergen challenge.

Topics: Allergens; Animals; Bronchoconstriction; Chymases; Disease Models, Animal; Eosinophils; Female; Hypersensitivity; Inflammation; Lung; Mast Cells; Mice; Mice, Inbred BALB C; Natural Killer T-Cells; Phenotype; Prostaglandin D2; Pyroglyphidae; Respiratory Hypersensitivity

Resveratrol, a natural polyphenol found in the skin of red grapes, is reported to have anti-inflammatory properties including protective effects against aging. Consequently, Resveratrol is a common nutritional supplement and additive in non-prescription lotions and creams marketed as anti-aging products. Studies in mice and with mouse bone marrow-derived mast cells (BMMCs) have indicated anti-allergic effects of Resveratrol. However, the effects of Resveratrol on human primary mast cells have not been reported.. Human mast cells were isolated and purified from normal skin tissue of different donors. The effect of Resveratrol on IgE-dependent release of allergic inflammatory mediators was determined using various immunoassays, Western blotting, and quantitative real-time PCR.. Resveratrol at low concentrations (≤10 μM) inhibited PGD2 biosynthesis but not degranulation. Accordingly, COX-2 expression was inhibited but phosphorylation of Syk, Akt, p38, and p42/44 (ERKs) remained intact. Surprisingly, TNF production was significantly enhanced with Resveratrol. At a high concentration (100 μM), Resveratrol significantly inhibited all parameters analyzed except Syk phosphorylation.. Here, we show that Resveratrol at low concentrations exerts its anti-inflammatory properties by preferentially targeting the arachidonic acid pathway. We also demonstrate a previously unrecognized pro-inflammatory effect of Resveratrol--the enhancement of TNF production from human mature mast cells following IgE-dependent activation.. These findings suggest that Resveratrol as a therapeutic agent could inhibit PGD2-mediated inflammation but would be ineffective against histamine-mediated allergic reactions. However, Resveratrol could potentially exacerbate or promote allergic inflammation by enhancing IgE-dependent TNF production from mast cells in human skin.

Topics: Animals; Cyclooxygenase 2; Dose-Response Relationship, Drug; Gene Expression Regulation; Humans; Hypersensitivity; Immunoglobulin E; MAP Kinase Signaling System; Mast Cells; Mice; Prostaglandin D2; Resveratrol; Skin; Stilbenes; Tumor Necrosis Factor-alpha

Lung allergic diseases sometimes accompany pulmonary vaso- and broncho-constriction. Rats are currently used for the experimental study of lung allergies. However, their hemodynamic mechanisms are not fully understood. Therefore the effects of allergic mediators were determined systematically in vivo in rats in terms of pulmonary vascular resistance (PVR), airway pressure (AWP) and total peripheral resistance (TPR). We directly measured pulmonary arterial pressure, left atrial pressure, systemic arterial pressure, central venous pressure and aortic blood flow to determine PVR and TPR, as well as AWP, following injections of platelet-activating factor (PAF), histamine, serotonin, leukotriene (LT) C4, and prostaglandin (PG) D2 in anesthetized open-chest artificially ventilated Sprague-Dawley (SD) rats. PVR was dose-dependently increased by consecutive administration of PAF, LTC4, and PGD2, with the maximal responsiveness being PAF>LTC4>PGD2. However, neither histamine nor serotonin changed PVR. TPR was decreased by all agents except LTC4 which actually increased it. PAF and serotonin, but not the other agents, increased AWP. In conclusion, allergic mediators exert non-uniform actions on pulmonary and systemic circulation and airways in anesthetized SD rats: PAF, LTC4 and PGD2, but not histamine or serotonin, caused substantial pulmonary vasoconstriction; LTC4 yielded systemic vasoconstriction, while the others caused systemic vasodilatation; only two mediators, PAF and serotonin, induce airway constriction.

Topics: Anesthesia; Animals; Arterial Pressure; Blood Circulation; Histamine; Hypersensitivity; Inflammation Mediators; Leukotriene C4; Lung; Male; Platelet Activating Factor; Prostaglandin D2; Rats, Sprague-Dawley; Serotonin; Vascular Resistance; Vasoconstriction

Mast cell (MC) mediators, among them prostaglandin D2 (PGD2) and 9α,11β-PGF2, PGD2's metabolite, play a key role in allergic reactions, including bee venom anaphylaxis (BVA). Assessment of these mediators has never been performed in BVA. The aim of the study was to assess the activation of MC during in vivo provocation with bee venom (BV) and to measure PGD2 and 9α,11β-PGF2 in the course of an allergen challenge. The second aim was to determine if assessment of these mediators could be useful for predicting adverse events during venom immunotherapy (VIT). In 16 BV-VIT patients and 12 healthy subjects, levels of PGD2 and 9α,11β-PGF2 were assessed during BV provocation by means of the skin chamber method. Chamber fluids, collected at 5 and 15 min, were analyzed for both mediators by gas chromatography mass spectrometry negative ion chemical ionization. BVA in comparison to non-allergic patients had a significantly higher ratio of 9α,11β-PGF2 in allergen-challenged chambers to 9α,11β-PGF2 in allergen-free chambers after 15 min of provocation (p = 0.039). Allergen challenge resulted in a significant increase of 9α,11β-PGF2 levels between 5 and 15 min after provocation only in BVA patients (p < 0.05). Analysis of log-transformed PGD2 levels showed significant difference between changes in PGD2 concentration between BVA and healthy subjects. No study patient developed adverse reactions during. 9α,11β-PGF2 is actively generated during the early allergic response to BV. Skin chamber seems to be a promising, non-invasive and safe model of in vivo allergen provocation in BV-allergic patients. High or low levels of both mediators do not predict occurrence of adverse events during VIT.

Topics: Adolescent; Adult; Aged; Allergens; Asthma; Bee Venoms; Biomarkers; Dinoprost; Female; Gas Chromatography-Mass Spectrometry; Humans; Hypersensitivity; Immunotherapy; Male; Mast Cells; Middle Aged; Multivariate Analysis; Prostaglandin D2; ROC Curve; Skin Tests; Young Adult

Allergic diseases, such as asthma and allergic rhinitis, are common. Therefore, the discovery of therapeutic drugs for these conditions is essential. Methyleugenol (ME) is a natural compound with antiallergic, antianaphylactic, antinociceptive, and anti-inflammatory effects. This study examined the antiallergic effect of ME on IgE-mediated inflammatory responses and its antiallergy mechanism in the mast cell line, RBL-2H3. We found that ME significantly inhibited the release of β-hexosaminidase, tumor necrosis factor- (TNF-) α, and interleukin- (IL-) 4, and was not cytotoxic at the tested concentrations (0-100 μM). Additionally, ME markedly reduced the production of the proinflammatory lipid mediators prostaglandin E2 (PGE2), prostaglandin D2 (PGD2), leukotriene B4 (LTB4), and leukotriene C4 (LTC4). We further evaluated the effect of ME on the early stages of the FcεRI cascade. ME significantly inhibited Syk phosphorylation and expression but had no effect on Lyn. Furthermore, it suppressed ERK1/2, p38, and JNK phosphorylation, which is implicated in proinflammatory cytokine expression. ME also decreased cytosolic phospholipase A2 (cPLA2) and 5-lipoxygenase (5-LO) phosphorylation and cyclooxygenase-2 (COX-2) expression. These results suggest that ME inhibits allergic response by suppressing the activation of Syk, ERK1/2, p38, JNK, cPLA2, and 5-LO. Furthermore, the strong inhibition of COX-2 expression may also contribute to the antiallergic action of ME. Our study provides further information about the biological functions of ME.

Topics: Animals; Arachidonic Acid; beta-N-Acetylhexosaminidases; Cell Line, Tumor; Cell Respiration; Dinoprostone; Eugenol; Extracellular Signal-Regulated MAP Kinases; Hypersensitivity; Immunoenzyme Techniques; Immunoglobulin E; Inflammation; Interleukin-4; Leukotriene B4; Leukotriene C4; Mast Cells; Mutagens; Prostaglandin D2; Rats; Tumor Necrosis Factor-alpha

Oblongifolin C (OC), a natural small molecule compound extracted from Garcinia yunnanensis Hu, has been previously shown to have anti-cancer effect, but the anti-allergic effect of OC has not yet been investigated. The aim of the present study is to determine the anti-allergic effect of OC on IgE/Ag-induced mouse bone marrow-derived mast cells (BMMCs) and on the passive systemic anaphylaxis (PSA) reaction in mice. OC clearly suppressed cyclooxygenase-2 (COX-2)-dependent prostaglandin D2 (PGD2) generation as well as leukotriene C4 (LTC4) generation and the degranulation reaction in IgE/Ag-stimulated BMMCs. Biochemical analyses of the IgE/Ag-mediated signaling pathways showed that OC suppressed the phosphorylation of phospholipase Cγ1 (PLCγ1)-mediated intracellular Ca(2+) influx and the nuclear factor-κB (NF-κB) pathway, as well as the phosphorylation of mitogen-activated protein (MAP) kinases. Although OC did not inhibit the phosphorylation of Fyn, Lyn, and Syk, it directly inhibited the tyrosine kinase activity in vitro. Moreover, oral administration of OC inhibited the IgE-induced PSA reaction in a dose-dependent manner. Taken together, the present study provides new insights into the anti-allergic activity of OC, which could be a promising candidate for allergic therapy.

Topics: Animals; Anti-Inflammatory Agents; Calcium; Cell Degranulation; Cells, Cultured; Drug Evaluation, Preclinical; Hypersensitivity; Leukotriene C4; Male; MAP Kinase Signaling System; Mast Cells; Mice, Inbred BALB C; Mice, Inbred ICR; NF-kappa B; Phosphorylation; Prostaglandin D2; Protein Processing, Post-Translational; Terpenes

Cheongseoikki-tang (CIT, Korean), also called Qingshu Yiqi decoction () and Seisho-ekki-to (Japanese), is well known as an effective traditional combination of herbs for treating cardiovascular diseases. This study was to research its effects on bone marrow-derived mast cell (BMMC)-mediated allergy and inflammation mechanisms.. In this study, the biological effect of Cheongseoikki-tang ethanol extract (CITE) was evaluated, focusing on its effects on the production of allergic mediators by phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187 (A23187)-stimulated BMMCs. These allergic mediators included interleukin-6 (IL-6), prostaglandin D2 (PGD2), leukotriene C4 (LTC4), and β-hexosaminidase (β-hex).. Our data revealed that CITE inhibited the production of IL-6, PGD2, LTC4, and β-hex induced by PMA plus A23187 (P<0.05).. These findings indicate that CITE has the potential for use in the treatment of allergy.

Topics: Animals; Anti-Inflammatory Agents; beta-N-Acetylhexosaminidases; Bone Marrow Cells; Calcimycin; Cell Degranulation; Cell Survival; Drugs, Chinese Herbal; Hypersensitivity; Interleukin-6; Leukotriene C4; Male; Mast Cells; Mice; Mice, Inbred BALB C; Prostaglandin D2; Tetradecanoylphorbol Acetate

Human linkage analyses have implicated the MS4A2-containing gene locus (encoding FcεRIβ) as a candidate for allergy susceptibility. We have identified a truncation of FcεRIβ (t-FcεRIβ) in humans that contains a putative calmodulin-binding domain and thus, we sought to identify the role of this variant in mast cell function. We determined that t-FcεRIβ is critical for microtubule formation and degranulation and that it may perform this function by trafficking adaptor molecules and kinases to the pericentrosomal and Golgi region in response to Ca2+ signals. Mutagenesis studies suggest that calmodulin binding to t-FcεRIβ in the presence of Ca2+ could be critical for t-FcεRIβ function. In addition, gene targeting of t-FcεRIβ attenuated microtubule formation, degranulation, and IL-8 production downstream of Ca2+ signals. Therefore, t-FcεRIβ mediates Ca2+ -dependent microtubule formation, which promotes degranulation and cytokine release. Because t-FcεRIβ has this critical function, it represents a therapeutic target for the downregulation of allergic inflammation.

Topics: Adaptor Proteins, Signal Transducing; Calcium; Calcium Signaling; Calmodulin-Binding Proteins; Cell Degranulation; Golgi Apparatus; Humans; Hypersensitivity; Immunoglobulin E; Interleukin-8; Mast Cells; Microtubules; Prostaglandin D2; Protein Isoforms; Receptors, IgE; RNA Interference; RNA Splicing; RNA, Messenger; RNA, Small Interfering

Eosinophils appear to be key cells in the pathogenesis of conjunctival inflammation in atopic keratoconjunctivitis (AKC). Chemoattractant receptor homologous molecule expressed on TH2 cells (CRTH2) mediates prostaglandin D2 (PGD2)-dependent migration of eosinophils. However, it is unclear whether CRTH2/PGD2-dependent eosinophil migration is upregulated in allergic diseases.. To compare the chemotactic responses of peripheral blood eosinophils to prostaglandin D2 in patients with severe AKC and healthy individuals.. We used an enzyme immunoassay system to measure PGD2 levels in tears and blood samples from healthy individuals and patients with AKC. CRTH2 expression on peripheral blood eosinophils was determined using reverse-transcriptase polymerase chain reaction (RT-PCR), flow cytometry, and an oligonucleotide array system. Chemotaxis experiments were performed using a modified Boyden chamber technique and an optical assay system.. The PGD2 concentrations were higher in tears from patients with severe AKC compared with healthy individuals. RT-PCR (severe and mild cases), flow cytometry (mild cases), and GeneChip analyses revealed a significantly higher expression of CRTH2 on peripheral blood eosinophils in patients with AKC than in healthy individuals. PGD2 and its stable metabolite 13,14-dihydro-15-keto-PGD2, a CRTH2 agonist, induced chemotaxis of eosinophils from patients with AKC; chemotaxis was significantly enhanced in eosinophils from patients with severe AKC compared with those from healthy individuals.. CRTH2 is more abundantly expressed on eosinophils from patients with AKC and promoted PGD2-dependent migration to a greater extent than in healthy individuals.

Topics: Adolescent; Adult; Chemotaxis, Leukocyte; Child; Enzyme-Linked Immunosorbent Assay; Eosinophils; Female; Flow Cytometry; Humans; Hypersensitivity; Keratoconjunctivitis; Male; Oligonucleotide Array Sequence Analysis; Prostaglandin D2; Receptors, Immunologic; Receptors, Prostaglandin; Reverse Transcriptase Polymerase Chain Reaction; Young Adult

The contribution of affinity, clonality, and concentration of individual IgE species to effector cell response has recently been characterized in a model with recombinant human IgE on passively sensitized basophils. This study extends the dependence of effector cell degranulation on IgE concentration to mast cells cultured with IgE for 2 weeks.. Human mast cells cultured for 7 weeks from peripheral blood stem cells were matured for 2 weeks with interleukin-4 (IL-4) and recombinant human IgE consisting of two clones specific for Dermatophagoides pteronyssinus 2 (Derp2) (7% + 7%) and unspecific IgE at 0.8, 8, 80, and 800 kU/L. The density of the IgE receptor, FcϵRI, and mast cell function were measured after challenging with recombinant Derp2 at 14 concentrations from 10 fg/mL to 100 pg/mL. CD63 expression, histamine release, and Prostaglandin D2 (PGD(2)) synthesis were measured, and maximal expression and mast cell sensitivity were calculated.. At 800 kU/L IgE, FcϵRI expression varied more than at 80, 8, and 0.8 kU/L IgE. There was a trend toward increased maximal expression of CD63, histamine release, and PGD(2) secretion with increasing IgE concentration. At 0.1 kU/L specific IgE, the LC50 increased up to fivefold, least so for PGD(2).. Human mast cells cultured with rhIgE of known composition are a sensitive model for studying factors governing effector cell degranulation that is close to the in vivo situation. This model can be used to study effects of IgE concentration, clonality, and affinity and may help predict the optimal immunologic treatment for a given patient.

Topics: Antigens, Dermatophagoides; Cell Degranulation; Histamine Release; Humans; Hypersensitivity; Immunoglobulin E; Leukocytes, Mononuclear; Mast Cells; Prostaglandin D2; Receptors, IgG; Statistics, Nonparametric; Tetraspanin 30

Recently, endogenous N-acyl dopamines have been found to show anti-inflammatory and immunomodulatory activities. However, the effect of the N-acyl dopamines on allergic responses was not reported. In this study, we investigated whether N-acyl dopamines might inhibit immunoglobulin E-mediated degranulation in RBL-2H3 cells. When RBL-2H3 cells were exposed to palmitoyl dopamine (NP-DA), oleoyl dopamine (NO-DA) or arachidonoyl dopamine (NA-DA) at micromolar levels, all these compounds significantly inhibited the release of β-hexosaminidase, a marker of degranulation, as well as tumor necrosis factor (TNF)-α. In comparison, NP-DA, potently suppressing the release of β-hexosaminidase (IC50, 3.5 μM) and TNF-α (IC50, 2.2 μM), was more potent than NO-DA or NA-DA. Additionally, NP-DA markedly suppressed the formation of prostaglandin E2, prostaglandin D2 and leukotriene C4, corresponding to pro-inflammatory lipid mediators in asthma. In the mechanistic analyses, where the effect of NP-DA on the FcεRI cascade was examined, NP-DA significantly inhibited the phosphorylation and expression of Syk, but not Lyn. And, NP-DA also suppressed phosphorylation of ERK1/2 and Akt. Further, NP-DA decreased the phosphorylation of cPLA2 and 5-lipoxygenase (5-LO), but not cyclooxygenase-2 (COX-2). Based on these results, it is suggested that NP-DA exert anti-allergic effect on allergic response through suppressing the activation of Syk, ERK1/2, Akt, cPLA2 and 5-LO. Besides, a strong inhibition of COX-2 activity by NP-DA may be additional mechanism for its anti-allergic action. Such an anti-allergic action of N-acyl dopamines may contribute to further information about biological functions of N-acyl dopamines.

Topics: Acylation; Animals; Anti-Allergic Agents; beta-N-Acetylhexosaminidases; Cell Degranulation; Dopamine; Hypersensitivity; Immunoglobulin E; Inflammation Mediators; Leukotriene C4; Mast Cells; Prostaglandin D2; Rats; Receptors, IgE; Tumor Necrosis Factor-alpha

We have previously reported that optimization of a series of phenylacetic acid derivatives led to the discovery of CRTH2 and DP dual antagonists, such as AMG 009 and AMG 853. During the optimization process, we discovered that minor structural modifications also afforded potent and selective CRTH2 or DP antagonists. Here we report the structure-activity relationship that led to the discovery of selective CRTH2 antagonists such as 2 and 17, and selective DP antagonists, such as 4 and 5.

Topics: Asthma; Chemistry, Pharmaceutical; Drug Design; Humans; Hypersensitivity; Inhibitory Concentration 50; Kinetics; Models, Chemical; Phenylacetates; Prostaglandin D2; Receptors, G-Protein-Coupled; Receptors, Immunologic; Receptors, Prostaglandin; Sulfonamides

Cinnamomum cambodianum has been used as a traditional medicine in Cambodia. Its effect on the bone marrow-derived mast cells (BMMCs) mediated allergic response remains unknown. In this study, a chloroform-soluble extract of C. cambodianum was evaluated for its effect on allergic mediators, including prostaglandin D₂ (PGD₂), leukotriene C₄ (LTC₄), β-hexosaminidase and cyclooxygenase-2 (COX-2) protein, in phorbol 12-myristate 13-acetate (PMA) plus calcimycin-stimulated BMMCs. The results revealed that the chloroform-soluble extract inhibited the production of interleukin-6, PGD₂ and LTC₄, and the expression of COX-2 in PMA plus calcimycin-stimulated BMMCs, implying a potential benefit of C. cambodianum in the treatment of allergy.

Topics: Animals; Bone Marrow Cells; Calcimycin; Calcium Ionophores; Carcinogens; Chloroform; Cinnamomum; Complex Mixtures; Cyclooxygenase 2; Female; Gene Expression Regulation, Enzymologic; Hypersensitivity; Interleukin-6; Leukotriene C4; Mast Cells; Mice; Mice, Inbred BALB C; Prostaglandin D2; Tetradecanoylphorbol Acetate

Mast cells are immune cells critical in the pathogenesis of allergic, but also inflammatory and autoimmune diseases through release of many pro-inflammatory cytokines such as IL-8 and TNF. Contact dermatitis and photosensitivity are skin conditions that involve non-immune triggers such as substance P (SP), and do not respond to conventional treatment. Inhibition of mast cell cytokine release could be effective therapy for such diseases. Unfortunately, disodium cromoglycate (cromolyn), the only compound marketed as a mast cell "stabilizer", is not particularly effective in blocking human mast cells. Instead, flavonoids are potent anti-oxidant and anti-inflammatory compounds with mast cell inhibitory actions. Here, we first compared the flavonoid quercetin (Que) and cromolyn on cultured human mast cells. Que and cromolyn (100 µM) can effectively inhibit secretion of histamine and PGD(2). Que and cromolyn also inhibit histamine, leukotrienes and PGD(2) from primary human cord blood-derived cultured mast cells (hCBMCs) stimulated by IgE/Anti-IgE. However, Que is more effective than cromolyn in inhibiting IL-8 and TNF release from LAD2 mast cells stimulated by SP. Moreover, Que reduces IL-6 release from hCBMCs in a dose-dependent manner. Que inhibits cytosolic calcium level increase and NF-kappa B activation. Interestingly, Que is effective prophylactically, while cromolyn must be added together with the trigger or it rapidly loses its effect. In two pilot, open-label, clinical trials, Que significantly decreased contact dermatitis and photosensitivity, skin conditions that do not respond to conventional treatment. In summary, Que is a promising candidate as an effective mast cell inhibitor for allergic and inflammatory diseases, especially in formulations that permit more sufficient oral absorption.

Topics: Anti-Allergic Agents; Antibodies, Anti-Idiotypic; Antigen-Antibody Complex; Calcium; Cells, Cultured; Cromolyn Sodium; Dermatitis, Contact; Histamine; Humans; Hypersensitivity; Immunoglobulin E; Interleukin-6; Interleukin-8; Leukotrienes; Mast Cells; NF-kappa B; Prostaglandin D2; Quercetin

Prostaglandin D2 (PGD2) regulates various immunological responses via two distinct PGD2 receptors, prostaglandin D receptor (DP), and chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2). Recent studies have demonstrated that PGD2 induces the migration of eosinophils through CRTH2. Although human eosinophils express both DP and CRTH2, it is unclear whether the function of DP is involved in eosinophil migration.. In this study, we investigated the roles of DP and CRTH2 in eosinophil migration by using selective agonists and antagonists.. Eosinophils were isolated from human subjects with mild eosinophilia by modified CD16-negative selection. After stimulation with or without DP receptor agonist, eosinophil migration was measured by Boyden chamber. The effect of DP agonists on CRTH2-induced eosinophil migration was studied in terms of CRTH2 expression, Ca2+ mobilization, ERK/MAPK phosphorylation, and cyclic AMP (cAMP) production.. Treatment with DP agonists inhibited CRTH2-induced chemotaxis of eosinophils. Furthermore, we showed that DP agonists enhanced cAMP production in CRTH2 agonist stimulation without increasing CRTH2 expression. DP mediates eosinophils through the elevation of intracellular cAMP production but does not change CRTH2 expression.. Taken together, the balance between DP and CRTH2 could influence the degree of PGD2-induced eosinophil migration and DP agonist might regulate eosinophil activation.

Topics: Blotting, Western; Calcium; Cells, Cultured; Chemotaxis; Cyclic AMP; Eosinophilia; Eosinophils; Humans; Hypersensitivity; Inflammation; Prostaglandin D2; Receptors, Immunologic; Receptors, Prostaglandin; Th2 Cells

PGD(2) is a key mediator of allergic inflammatory diseases that is mainly synthesized by mast cells, which constitutively express high levels of the terminal enzyme involved in PGD(2) synthesis, the hematopoietic PGD synthase (H-PGDS). In this study, we investigated whether eosinophils are also able to synthesize, and therefore, supply biologically active PGD(2). PGD(2) synthesis was evaluated within human blood eosinophils, in vitro differentiated mouse eosinophils, and eosinophils infiltrating inflammatory site of mouse allergic reaction. Biological function of eosinophil-derived PGD(2) was studied by employing inhibitors of synthesis and activity. Constitutive expression of H-PGDS was found within nonstimulated human circulating eosinophils. Acute stimulation of human eosinophils with A23187 (0.1-5 μM) evoked PGD(2) synthesis, which was located at the nuclear envelope and was inhibited by pretreatment with HQL-79 (10 μM), a specific H-PGDS inhibitor. Prestimulation of human eosinophils with arachidonic acid (10 μM) or human eotaxin (6 nM) also enhanced HQL-79-sensitive PGD(2) synthesis, which, by acting on membrane-expressed specific receptors (D prostanoid receptors 1 and 2), displayed an autocrine/paracrine ability to trigger leukotriene C(4) synthesis and lipid body biogenesis, hallmark events of eosinophil activation. In vitro differentiated mouse eosinophils also synthesized paracrine/autocrine active PGD(2) in response to arachidonic acid stimulation. In vivo, at late time point of the allergic reaction, infiltrating eosinophils found at the inflammatory site appeared as an auxiliary PGD(2)-synthesizing cell population. Our findings reveal that eosinophils are indeed able to synthesize and secrete PGD(2), hence representing during allergic inflammation an extra cell source of PGD(2), which functions as an autocrine signal for eosinophil activation.

Topics: Animals; Autocrine Communication; Catalysis; Eosinophils; Female; Hematopoiesis; Humans; Hypersensitivity; Inflammation; Intracellular Fluid; Intramolecular Oxidoreductases; Lipocalins; Male; Mice; Mice, Inbred BALB C; Paracrine Communication; Prostaglandin D2; Receptors, Immunologic; Receptors, Prostaglandin

Allergies are highly complex disorders with clinical manifestations ranging from mild oral, gastrointestinal, recurrent wheezing, and cutaneous symptoms to life-threatening systemic conditions. The levels of arachidonic acid, eicosanoids, histamine, organic acids and valine are considered to have a variety of physiological functions in connection with allergies. In this research, we have developed a RP-LC/MS method to separate and quantitate six different potential endogenous biomarkers, including leukotriene B(4) (LTB(4)), prostaglandin D(2) (PGD(2)), arachidonic acid (AA), histamine (HI), lactic acid (LA) and valine (VAL), from serum of rats with ovalbumin (OVA)-induced allergy and normal rats, and the discrepancies between the model group and the control group were compared. The separation was performed on a Prevail C18 column (250 mm x 4.6 mm, 5 microm) with a gradient elution of acetonitrile with 0.1% formic acid (v/v) and 10 mM ammonium formate (adjusted to pH 4.0 with formic acid) at a flow rate of 0.5 mL min(-1) The method was validated and shown to be sensitive, accurate (recovery values 76.16-92.57%) and precise (RSD < 10% for all compounds) with a linear range over several orders of magnitude. The method was successfully applied to rat serum and shown to be indicative of the endogenous levels of biomarkers within the rat body. The analysis of the biomarkers can provide insight into the allergic mechanisms associated with related diseases.

Topics: Animals; Arachidonic Acid; Biomarkers; Chromatography, Liquid; Histamine; Hypersensitivity; Lactic Acid; Leukotriene B4; Mass Spectrometry; Ovalbumin; Prostaglandin D2; Rats; Sensitivity and Specificity; Valine

Activated mast cells are a major source of the eicosanoids PGD(2) and leukotriene C(4) (LTC(4)), which contribute to allergic responses. These eicosanoids are produced following the ERK1/2-dependent activation of cytosolic phospholipase A(2), thus liberating arachidonic acid, which is subsequently metabolized by the actions of 5-lipoxygenase and cyclooxygenase to form LTC(4) and PGD(2), respectively. These pathways also generate reactive oxygen species (ROS), which have been proposed to contribute to FcepsilonRI-mediated signaling in mast cells. In this study, we demonstrate that, in addition to ERK1/2-dependent pathways, ERK1/2-independent pathways also regulate FcepsilonRI-mediated eicosanoid and ROS production in mast cells. A role for the Tec kinase Btk in the ERK1/2-independent regulatory pathway was revealed by the significantly attenuated FcepsilonRI-dependent PGD(2), LTC(4), and ROS production in bone marrow-derived mast cells of Btk(-/-) mice. The FcepsilonRI-dependent activation of Btk and eicosanoid and ROS generation in bone marrow-derived mast cells and human mast cells were similarly blocked by the PI3K inhibitors, Wortmannin and LY294002, indicating that Btk-regulated eicosanoid and ROS production occurs downstream of PI3K. In contrast to ERK1/2, the PI3K/Btk pathway does not regulate cytosolic phospholipase A(2) phosphorylation but rather appears to regulate the generation of ROS, LTC(4), and PGD(2) by contributing to the necessary Ca(2+) signal for the production of these molecules. These data demonstrate that strategies to decrease mast cell production of ROS and eicosanoids would have to target both ERK1/2- and PI3K/Btk-dependent pathways.

Topics: Agammaglobulinaemia Tyrosine Kinase; Androstadienes; Animals; Antigens; Arachidonate 5-Lipoxygenase; Arachidonic Acid; Bone Marrow Cells; Calcium Signaling; Chromones; Enzyme Activation; Enzyme Inhibitors; Humans; Hypersensitivity; Leukotriene C4; MAP Kinase Signaling System; Mast Cells; Mice; Mice, Knockout; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Morpholines; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Phospholipases A2, Cytosolic; Phosphorylation; Prostaglandin D2; Protein-Tyrosine Kinases; Reactive Oxygen Species; Receptors, IgE; Wortmannin

We have reported previously the development of an optically accessible, horizontal chemotaxis apparatus, in which migration of cells in the channel from a start line can be traced with time-lapse intervals using a CCD camera (JIM 282, 1-11, 2003). To obtain statistical data of migrating cells, we have developed quantitative methods to calculate various parameters in the process of chemotaxis, employing human eosinophil and CXCL12 as a model cell and a model chemoattractant, respectively. Median values of velocity and directionality of each cell within an experimental period could be calculated from the migratory pathway data obtained from time-lapse images and the data were expressed as Velocity-Directionality (VD) plot. This plot is useful for quantitatively analyzing multiple migrating cells exposed to a certain chemoattractant, and can distinguish chemotaxis from random migration. Moreover precise observation of cell migration revealed that each cell had a different lag period before starting chemotaxis, indicating variation in cell sensitivity to the chemoattractant. Thus lag time of each cell before migration, and time course of increment of the migrating cell ratio at the early stages could be calculated. We also graphed decrement of still moving cell ratio at the later stages by calculating the duration time of cell migration of each cell. These graphs could distinguish different motion patterns of chemotaxis of eosinophils, in response to a range of chemoattractants; PGD(2), fMLP, CCL3, CCL5 and CXCL12. Finally, we compared parameters of eosinophils from normal volunteers, allergy patients and asthma patients and found significant difference in response to PGD(2). The quantitative methods described here could be applicable to image data obtained with any combination of cells and chemoattractants and useful not only for basic studies of chemotaxis but also for diagnosis and for drug screening.

Topics: Adult; Case-Control Studies; Cell Movement; Chemokine CXCL12; Chemokines, CXC; Chemotactic Factors; Chemotaxis, Leukocyte; Eosinophils; Female; Humans; Hypersensitivity; LIM Domain Proteins; Male; Middle Aged; Muscle Proteins; Optical Devices; Optics and Photonics; Prostaglandin D2

The chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2) is a G protein-coupled receptor that mediates the pro-inflammatory effects of prostaglandin D(2) (PGD(2)) generated in allergic inflammation. The CRTH2 receptor shares greatest sequence similarity with chemoattractant receptors compared with prostanoid receptors. To investigate the structural determinants of CRTH2 ligand binding, we performed site-directed mutagenesis of putative mCRTH2 ligand-binding residues, and we evaluated mutant receptor ligand binding and functional properties. Substitution of alanine at each of three residues in the transmembrane (TM) helical domains (His-106, TM III; Lys-209, TM V; and Glu-268, TM VI) and one in extracellular loop II (Arg-178) decreased PGD(2) binding affinity, suggesting that these residues play a role in binding PGD(2). In contrast, the H106A and E268A mutants bound indomethacin, a nonsteroidal anti-inflammatory drug, with an affinity similar to the wild-type receptor. HEK293 cells expressing the H106A, K209A, and E268A mutants displayed reduced inhibition of intracellular cAMP and chemotaxis in response to PGD(2), whereas the H106A and E268A mutants had functional responses to indomethacin similar to the wild-type receptor. Binding of PGE(2) by the E268A mutant was enhanced compared with the wild-type receptor, suggesting that Glu-268 plays a role in determining prostanoid ligand selectivity. Replacement of Tyr-261 with phenylalanine did not affect PGD(2) binding but decreased the binding affinity for indomethacin. These results provided the first details of the ligand binding pocket of an eicosanoid-binding chemoattractant receptor.

Topics: Alanine; Animals; Anti-Inflammatory Agents, Non-Steroidal; Binding, Competitive; Cell Line; Cell Movement; Chemotactic Factors; Chemotaxis; Cyclic AMP; Dose-Response Relationship, Drug; Eicosanoids; Enzyme-Linked Immunosorbent Assay; Flow Cytometry; Glutamic Acid; Humans; Hypersensitivity; Indomethacin; Inflammation; Kinetics; Ligands; Mice; Models, Biological; Models, Molecular; Mutagenesis, Site-Directed; Mutation; Phenylalanine; Prostaglandins; Protein Binding; Protein Structure, Tertiary; Receptors, G-Protein-Coupled; Receptors, Immunologic; Receptors, Prostaglandin; Tyrosine

Allergic pathologies are often associated with IgE production, mast cell activation, and eosinophilia. PGD2 is the major eicosanoid, among several inflammatory mediators, released by mast cells. PGD2 binds to two membrane receptors, D prostanoid receptor (DP)1 and DP2, endowed with antagonistic properties. In humans, DP2 is preferentially expressed on type 2 lymphocytes, eosinophils, and basophils and mediates chemotaxis in vitro. Although not yet supported by in vivo studies, DP2 is thought to be important in the promotion of Th2-related inflammation. Herein, we demonstrate that mouse eosinophils express both DP1 and DP2 and that PGD2 exerts in vitro chemotactic effects on eosinophils through DP2 activation. Furthermore, 13,14-dihydro-15-keto-PGD2, a specific DP2 agonist not only increases eosinophil recruitment at inflammatory sites but also the pathology in two in vivo models of allergic inflammation: atopic dermatitis and allergic asthma. By contrast, DP1 activation tends to ameliorate the pathology in asthma. Taken together, these results support the hypothesis that DP2 might play a critical role in allergic diseases and underline the interest of DP2 antagonists in human therapy.

Topics: Animals; Asthma; Base Sequence; Chemotaxis, Leukocyte; Dermatitis, Atopic; DNA; Eosinophilia; Eosinophils; Female; Gene Expression; Humans; Hypersensitivity; In Vitro Techniques; Inflammation; Mice; Mice, Inbred BALB C; Mice, Transgenic; Prostaglandin D2; Receptors, Immunologic; Receptors, Prostaglandin; RNA, Messenger

Cyclooxygenase (COX) is a key enzyme in prostaglandin (PG) synthesis. Up-regulation of COX-2 expression is responsible for increased PG release during inflammatory conditions and is thought to be also involved in allergic states. In this study, we demonstrate that in human T, B and natural killer lymphocytes from allergic patients, COX-2 expression became induced upon cell challenge with specific allergens and that this process is presumably IgE dependent and occurs after CD23 receptor ligation. This induction took place at both mRNA and protein levels and was accompanied by PGD2 release. IgE-dependent lymphocyte treatment elicited, in parallel, an activation of the MAPK p38 and extracellular signal-regulated kinase 1/2, an enhancement of calcineurin (CaN) activity, and an increase of the DNA-binding activity of the nuclear factor of activated T cells and of NF-kappaB, with a concomitant decrease in the levels of the cytosolic inhibitor of kappaB, IkappaB. In addition, specific chemical inhibitors of MAPK, such as PD098059 and SB203580, as well as MG-132, an inhibitor of proteasomal activity, abolished allergen-induced COX-2 up-regulation, suggesting that this process is mediated by MAPK and NF-kappaB. However, induction of COX-2 expression was not hampered by the CaN inhibitor cyclosporin A. We also examined the effect of a selective COX-2 inhibitor, NS-398, on cytokine production by human lymphocytes. Treatment with NS-398 severely diminished the IgE-dependently induced production of IL-8 and TNF-alpha. These results underscore the relevant role of lymphocyte COX-2 in allergy and suggest that COX-2 inhibitors may contribute to the improvement of allergic inflammation through the reduction of inflammatory mediator production by human lymphocytes.

Topics: Allergens; Cells, Cultured; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Cyclooxygenase Inhibitors; DNA-Binding Proteins; Humans; Hypersensitivity; Immunoglobulin E; Interleukin-8; Membrane Proteins; Mitogen-Activated Protein Kinases; NF-kappa B; NFATC Transcription Factors; Nuclear Proteins; Prostaglandin D2; Prostaglandin-Endoperoxide Synthases; RNA, Messenger; T-Lymphocyte Subsets; Transcription Factors; Tumor Necrosis Factor-alpha; Up-Regulation

Both prostaglandin (PG) D receptor (DP) and CRTH2 (chemoattractant receptor-homologous molecule expressed on Th2 cells)/DP2 are high-affinity receptors for PGD2. Previous studies have demonstrated that PGD2 enhances releasability and induces CRTH2/DP2-mediated migration in human basophils, but the precise effects of PGD2 on basophils as well as receptor usage have not been fully clarified.. We comprehensively explored the roles of DP and CRTH2/DP2 in basophil functions by using selective agonists and antagonists for each receptor.. DP and CRTH2/DP2 transcripts were quantified by real-time PCR. We studied the effects of selective agonists (DP: BW245C; CRTH2/DP2: 13,14-dihydro-15-keto (DK)-PGD2) and/or antagonists (DP: BWA868C; CRTH2/DP2: ramatroban) on Ca2+ mobilization, migration, degranulation, CD11b expression and survival of human basophils.. Basophils expressed transcripts of both DP and CRTH2/DP2, but the levels of CRTH2/DP2 transcripts were ca. 100-fold higher compared with DP transcripts. Ca2+ influx was induced in basophils by either PGD2 or DK-PGD2/CRTH2 agonist but not by BW245C/DP agonist. Basophils treated with PGD2 were completely desensitized to subsequent stimulation with DK-PGD2, but not vice versa. DK-PGD2 as well as PGD2 up-regulated CD11b expression, induced migration and enhanced degranulation, and those effects were completely antagonized by ramatroban/CRTH2 antagonist. In contrast, BW245C/DP agonist exhibited an inhibitory effect on basophil migration and IgE-mediated degranulation, and the migration inhibitory effect was effectively antagonized by BWA868C/DP antagonist. On the other hand, while PGD2 significantly shortened the basophil life-span, neither DK-PGD2/CRTH2 agonist nor BW245C/DP agonist did.. CRTH2/DP2 is primarily responsible for the pro-inflammatory effects of PGD2 on human basophils, while DP introduces negative signals capable of antagonizing the effects of CRTH2/DP2 in these cells. The effects of PGD2 on longevity imply a mechanism(s) other than via DP or CRTH2/DP2. CRTH2/DP2 on basophils may afford opportunities for therapeutic targeting in allergic inflammation.

Topics: Basophils; Calcium; CD11b Antigen; Cell Movement; Cell Survival; Cells, Cultured; Chemotaxis; Histamine Release; Humans; Hydantoins; Hypersensitivity; Prostaglandin D2; Receptors, Immunologic; Receptors, Prostaglandin; Reverse Transcriptase Polymerase Chain Reaction; Th2 Cells

The allergic reaction begins with the antigen-induced aggregation of occupied high-affinity IgE receptors expressed on mast cell surface, their activation, and the release of proinflammatory mediators that cause the "early phase" of this process. In addition, mast cell activation induces the onset of a "late phase" reaction characterized by the tissue infiltration of inflammatory cells, mainly eosinophils. We have hypothesized that during the late phase mast cells interact with and are activated by eosinophils. Here we report that highly purified human lung mast cells became responsive to eosinophil major basic protein (MBP) when in coculture with human lung fibroblasts. In addition, cord blood-derived mast cells maintained in coculture with 3T3 fibroblasts released more histamine and prostaglandin D(2) (PGD(2)) compared with cells maintained in suspension. The fibroblast-derived membrane form of stem cell factor (SCF) was found to be involved in the mast cell increased responsiveness to MBP. In fact, cord blood-derived mast cells cocultured with 3T3 in the presence of antisense for SCF or cocultured with fibroblasts that do not express the membrane form of SCF were inhibited in their histamine-releasing activity toward MBP. In addition, this form of SCF induced the expression of a pertussis toxin-sensitive G(i) protein, G(i3) that interacts with MBP to trigger mast cell non-IgE-dependent activation in a manner similar to other cationic compounds such as compound 48/80. Mast cell responsiveness to eosinophil mediators is a potentially novel evidence for an alternative pathway of allergen-independent activation able to contribute to the perpetuation of allergy.

Topics: 3T3 Cells; Adult; Animals; Blood Proteins; Cell Culture Techniques; Coculture Techniques; Eosinophil Granule Proteins; Fetal Blood; Fibroblasts; Gene Expression Regulation; GTP-Binding Protein alpha Subunits, Gi-Go; Heterotrimeric GTP-Binding Proteins; Histamine Release; Humans; Hypersensitivity; Immunoglobulin E; Infant, Newborn; Lung; Mast Cells; Membrane Proteins; Mice; Oligodeoxyribonucleotides, Antisense; Organ Specificity; Peritoneal Cavity; Pertussis Toxin; Prostaglandin D2; Protein Isoforms; Rats; Ribonucleases; Stem Cell Factor

Topics: Anti-Inflammatory Agents; Butyrophenones; Cells, Cultured; Cetirizine; Chymases; Eosinophils; Granulocyte Colony-Stimulating Factor; Granulocyte-Macrophage Colony-Stimulating Factor; Hematopoietic Cell Growth Factors; Histamine; Histamine H1 Antagonists; Humans; Hypersensitivity; Intercellular Adhesion Molecule-1; Interleukin-3; Interleukin-8; Loratadine; Mast Cells; Piperidines; Potassium Channel Blockers; Potassium Channels; Prostaglandin D2; Pyridines; Recombinant Fusion Proteins; Recombinant Proteins; Serine Endopeptidases; Terfenadine; Time Factors; Tryptases

The goal of the current study was to examine the formation of phospholipids, 1-radyl-2-lysosn-glycero-phospholipids (lyso-PL) and 2-acetylated phospholipids (such as PAF) as well as mechanisms responsible for generating these phospholipids in bronchoalveolar lavage fluid (BAI.F) from allergic subjects challenged with antigen. Bronchoalveolar lavage was performed in normal and allergic subjects before, 5-30 min, 6 h, and 20 h after segmental antigen challenge via a wedged bronchoscope. Levels of 1-hexadecyl-2-lyso-phospholipids and 1-hexadecyl-2-acetyl-phospholipids were initially determined by negative ion chemical ionization gas chromatography/mass spectrometry (NICI-GC/MS). Antigen dramatically elevated quantities of 1-hexadecyl-2-lyso-phospholipids in allergic subjects 20 h after challenge when compared to non-allergic controls. In contrast, there was not a significant increase in levels of 1-hexadecyl-2-acetyl-phospholipids after antigen challenge. Closer examination of 1-radyl-2-lyso-sn-glycero-3-phosphocholine (GPC) revealed that 1-palmitoyl-2-lyso-GPC, 1-myristoyl-2-lyso-GPC and 1-hexadecyl-2-lyso-GPC were three major molecular species produced after antigen challenge. 1-palmitoyl-2-lyso-GPC increased sevenfold to levels of 222 +/- 75 ng/ml of BALF 20 h after antigen challenge. The elevated levels of lyso-PL correlated with levels of albumin used to assess plasma exudation induced by allergen challenge. In contrast, the time course of prostaglandin D2 (PGD2) or 9 alpha, 11 beta PGF2 (11 beta PGF2) formation did not correlate with lyso-PL generation. To examine the mechanism leading to lyso-phospholipid formation in antigen-challenged allergic subjects, secretory phospholipase A2 (PI.A2) and acetyl hydrolase activities were measured. There was a significant increase in PLA2 activity found in BALF of allergic subjects challenged with antigen when compared to saline controls. This activity was neutralized by an antibody directed against low molecular mass, (14 kD) human synovial PLA2 and dithiothreitol. Acetyl hydrolase activity also markedly increased in BALF obtained after antigen challenge. This study indicates that high levels of lyso-PLs are present in airways of allergic subjects challenged with antigen and provides evidence for two distinct mechanisms that could induce lyso-PL formation. Future studies will be necessary to determine the ramifications of these high levels of lyso-phospholipids on airway function.

Topics: Adult; Asthma; Bronchoalveolar Lavage; Bronchoalveolar Lavage Fluid; Dinoprost; Female; Gas Chromatography-Mass Spectrometry; Humans; Hypersensitivity; Lysophospholipids; Male; Methacholine Chloride; Prostaglandin D2; Reference Values; Rhinitis; Time Factors

Topics: Chymases; Dinoprost; Histamine Release; Humans; Hypersensitivity; Mast Cells; Nasal Provocation Tests; Prostaglandin D2; Serine Endopeptidases; Time Factors; Tryptases

1. The effects of salmeterol, a novel long-acting beta 2-adrenoceptor agonist, have been investigated on antigen-induced mediator release from passively sensitized fragments of human lung in vitro. 2. Salmeterol was a potent inhibitor of the release of histamine (-log IC50 = 8.54), leukotriene C4 (LTC4)/LTD4 (-log IC50 = 9.07) and prostaglandin D2 (-log IC50 = 8.81). It was slightly less potent (1-3 fold) than isoprenaline, but significantly more potent (10-35 fold) than salbutamol. 3. Propranolol competitively antagonized the inhibitory effects of salmeterol on histamine release (pA2 = 8.41) and LTC4/LTD4 release, (pA2 = 8.40) indicating an action via beta-adrenoceptors. 4. The inhibitory effects of isoprenaline (20 nM) and salbutamol (200 nM) were removed after washing the lung tissue for 2 h and 4 h respectively. In contrast, the inhibitory effects of salmeterol (40 nM) were much longer-lasting, and were still evident after 20 h. 5. Salmeterol therefore exhibits potent and persistent inhibition of anaphylactic mediator release from human lung. This anti-inflammatory effect may be important for the therapeutic potential of salmeterol in the treatment of bronchial asthma.

Topics: Adrenergic beta-Agonists; Albuterol; Histamine Release; Humans; Hypersensitivity; In Vitro Techniques; Inflammation; Lung; Mast Cells; Propranolol; Prostaglandin D2; Salmeterol Xinafoate; SRS-A

In asthmatics, both the continuous release of mast cell-derived inflammatory mediators and damage of the airway epithelium may be related to the degree of bronchial responsiveness. We therefore evaluated the effect of inflammatory mediators and mast cell activation on the cholinergic responsiveness of strips of human bronchioles with and without epithelium. Cumulative concentration-response curves to methacholine were generated from strips with or without epithelium before, during and after incubation with threshold doses of either methacholine (3 x 10(-7) M, controls), histamine (3 x 10(-7) M), the thromboxane A2 analogue, U46619 (10(-9) M), prostaglandin (PG) D2 (3 x 10(-7) M), PGF2 alpha (3 x 10(-7) M), leukotriene (LT) C4 (10(-9) M), or anti-human immunoglobulin E (24.4 +/- 4.0 micrograms.ml-1). Strips without epithelium were 1.6 times more sensitive to methacholine than strips with epithelium (-log EC50:5.76 +/- 0.04 vs. 5.97 +/- 0.04, P less than 0.0001). The average contraction in response to identical doses of anti-IgE in strips without epithelium was 3 times greater than the contraction in strips with epithelium (P less than 0.05). Threshold concentrations of histamine, U44619 and PGD2 caused a similar non-parallel leftward shift of the concentration-response curve of strips with or without epithelium to methacholine (P less than 0.05). Together, epithelial denudation and low levels of mediators caused a 4.0- to 9.1-fold increase in sensitivity based on the -log EC10 and a 1.8- to 3.0-fold increase in sensitivity based on the -log EC50.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; Aged; Aged, 80 and over; Antibodies, Anti-Idiotypic; Dinoprost; Epithelium; Histamine; Humans; Hypersensitivity; Immunoglobulin E; In Vitro Techniques; Inflammation; Kinetics; Lung; Male; Mast Cells; Methacholine Chloride; Middle Aged; Muscle Contraction; Prostaglandin D2; Prostaglandin Endoperoxides, Synthetic; SRS-A

Topics: Binding Sites; Histamine; Humans; Hypersensitivity; Immunoglobulin E; Lung; Prostaglandin D2; Pyrilamine; SRS-A

Interleukin-1 (IL-1) promotes cell recruitment and influences allergic mediator release. We analyzed histamine, prostaglandin D2, IL-1, and leukocytes accumulating hourly for 12 hours at skin-chamber sites after local ragweed challenge in eight allergic subjects with cutaneous late-phase reactions. Ragweed induced a peak of histamine at 1 hour (p less than 0.02), which diminished, and then steadily increased (p less than 0.02). Prostaglandin D2 levels peaked by the second hour (p less than 0.02) and then decreased, approaching prechallenge levels by 12 hours. Leukocyte infiltration (predominantly neutrophils) was detectable 3 to 4 hours after challenge, although selective enrichment of mononuclear cells, eosinophils, and basophils ws observed at later hours (p less than 0.02). IL-1 bioactivity was detected in fluids 10 to 12 hours after challenge but not at control sites (p less than 0.05). Analysis of IL-1 beta levels by RIA revealed an initial peak at 1 hour of 0.90 ng/ml (p less than 0.02) and a second elevation of up to 0.75 ng/ml during the later hours (p less than 0.04). Ragweed challenge of three nonatopic subjects did not change levels of the above-mentioned mediators or cells. Bioactivity in chamber fluids from antigen-challenged sites of atopic subjects was significantly neutralized by an anti-IL-1 beta antiserum, although treatment with anti-IL-1 alpha and anti-IL-1 beta was needed for complete neutralization, IL-1 released locally during cutaneous allergic reactions may contribute to IgE-dependent cutaneous inflammation.

Topics: Adolescent; Adult; Dose-Response Relationship, Drug; Female; Histamine; Humans; Hypersensitivity; Interleukin-1; Male; Middle Aged; Neutralization Tests; Pollen; Prostaglandin D2; Radioimmunoassay; Skin; Skin Tests

To understand better the response of patients with allergic rhinitis to nasal challenge with antigen, we studied the mechanism of priming, that is, the increased clinical response to daily sequential nasal challenges. Ten subjects with ragweed hay fever were challenged four times with increasing doses of ragweed pollen. The first 2 challenge days were separated by 2 weeks, whereas the last three challenges occurred on sequential days. Nasal lavages, performed before and after each nasal challenge, were evaluated for levels of inflammatory mediators and cellular content. In contrast to control days, a significant (p less than 0.05) increase in the number of sneezes occurred on both priming days. Priming was associated with a significant increase in the level of histamine on both priming days, whereas the second priming day was also associated with an increase in TAME-esterase activity, kinins, and prostaglandin D2 obtained after challenge (p less than 0.05 for all). In the lavages before challenge on the priming days, the total number of cells and the number of neutrophils, eosinophils, and alcian blue-positive cells were significantly increased, but in contrast, basal levels of mediators were not. The net increase in the number of alcian blue-positive cells correlated with the net increase in the amount of histamine released on the priming days (r = 0.661; p less than 0.05). These studies suggest that priming results, in part, from increased mediator release from influxing inflammatory cells.

Topics: Eosinophils; Histamine Release; Humans; Hypersensitivity; Nose; Pollen; Prostaglandin D2; Sneezing

Nasal challenges with pollen grains represent one of the techniques of provocation. However, the clinical criteria of positivity are not clearly established. Nasal challenges with increasing numbers of orchard-grass pollen grains were performed in 60 patients allergic to grass pollens and 20 normal subjects. Before any challenge, the nose was washed three times with saline and then lactose, and 50, 150, 450, 1350, and 4050 orchard-grass pollen grains were insufflated into the nostrils until a symptom score of 5 was reached. This score was mainly based on major symptoms of allergic rhinitis, for example, rhinorrhea, nasal obstruction, sneezes, and to a lesser extent, on minor symptoms, such as pruritus, conjunctivitis, and pharyngitis. Nasal secretions were obtained after each challenge by lavage. Histamine was titrated by a radioimmunoassay with a monoclonal antibody against acylated histamine. Prostaglandin D2 (PGD2) was assayed with an enzyme immunoassay with a polyclonal antibody against PGD2 methoxamine. None of the normal subjects had a symptom score greater than 2; 55/60 patients had a positive challenge. The release of PGD2 was significantly (p less than 0.001, Kruskal-Wallis test) correlated with a symptom score of 5; 74.5% of patients had a significant release of PGD2 in nasal secretions. In contrast, although 58.2% of patients had a release of histamine in nasal secretions when the challenge was positive, the correlation with symptom scores was not significant. PGD2 in nasal secretions increased 3.7-fold after a positive nasal challenge.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adolescent; Adult; Dose-Response Relationship, Immunologic; Histamine Release; Humans; Hypersensitivity; Male; Middle Aged; Nasal Mucosa; Nasal Provocation Tests; Poaceae; Pollen; Prostaglandin D2; Reproducibility of Results

Insight into the pathogenesis of human allergic and inflammatory disorders has been obtained through a combination of in vitro and in vivo studies. These investigations have demonstrated that human basophils and mast cells release mediators after nonimmunologic as well as immunologic activation in vitro and in vivo: nonimmunologic triggers include changes in osmolarity. Although these cells share many properties, including the presence of high-affinity receptors for IgE on their cell surface, the presence of histamine in granules, the ability to generate and release large quantities of leukotriene C4 (LTC4) after activation, and the ability of several pharmacologic agents including phospholipase inhibitors, acetylene analogues of arachidonic acid (ETYA, ETI), methylxanthines, prostaglandin E2 (PGE2) beta-agonists, and cyclic AMP to inhibit mediator release, they also display notable differences. Human lung mast cells generate and release large quantities of prostaglandin D2 (PGD2) after activation; basophils generate no known cyclooxygenase product. Indomethacin, arachidonic acid, and 5-hydroperoxyeicosatetraenoic acid (5-HPETE) all enhance histamine and LTC4 release from human basophils; no effect is seen with human lung mast cells. Overnight incubation of basophils with glucocorticoids produces a marked inhibition of mediator release; this treatment does not affect the release of mast cell mediators. These in vitro observations are consistent with our in vivo observations and our hypotheses concerning the importance of these cells in allergic disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Antibodies, Anti-Idiotypic; Antigens; Basophils; Histamine; Humans; Hypersensitivity; Immunoglobulin E; Mast Cells; Prostaglandin D2; Prostaglandins D; Rhinitis; SRS-A

Intranasal challenge of allergic subjects with the allergen to which they are sensitive rapidly produces sneezing, rhinorrhea, and airway obstruction. Nasal washings during the response reveal increased amounts of histamine, leukotrienes, prostaglandin D2 (PgD2), kinins and TAME-esterase in secretions. Although appearance of these mediators ceases shortly after challenge, many patients have a recrudescence of symptoms 3-11 h later, with a reappearance of the same mediators with the notable exception of PgD2. Subjects who respond to exposure to cold with rhinorrhea and nasal stuffiness were subjected to a 15-min nasal challenge with cold (-3-10 degrees C) dry (10% relative humidity) air and also responded with typical symptoms and the appearance of histamine, PgD2, TAME-esterase and leukotrienes. Nasal challenge with ragweed pollen by patients on immunotherapy showed that the threshold for response was greater and the amount of mediator found was less after treatment.

Topics: Airway Resistance; Allergens; Histamine Release; Humans; Hypersensitivity; Kinins; Nasal Mucosa; Nasal Provocation Tests; Peptide Hydrolases; Pollen; Prostaglandin D2; Prostaglandins D; Sneezing; SRS-A

The role of human basophils and mast cells in the pathogenesis of allergic diseases has been analyzed. Purified human basophils and mast cells release several known mediators of allergic reactions, including histamine, sulfidopeptide leukotrienes, kinin-forming enzymes, and, in the case of the mast cell, PGD2. These same mediators are released in vivo after experimental challenge in the upper airways with either allergen or cold, dry air, a stimulus used to simulate exercise-induced bronchospasm. The appearance of mast cell mediators in vivo after such challenges further implicates mast cells in the pathogenesis of allergic diseases of the airways that occur as a result of exposure to allergen or physical stimuli. During the LPR after experimental challenge of the upper airways, the pattern of mediators released (i.e., histamine, leukotrienes, and others, but no PGD2) suggests that basophils may contribute to the LPR. Antiallergic drugs that prevent mediator release in vitro, such as antihistamines, also prevent the appearance of mediators in vivo, strengthening both the validity of the in vitro test as a model of the disease and the hypothesis that mediator release is an essential element of the disease process. A model discussing the pathogenetic mechanism is presented.

Topics: Adrenal Cortex Hormones; Basophils; Capillary Permeability; Cold Temperature; Eosinophils; Histamine Release; Humans; Hypersensitivity; Immunoglobulin E; Inflammation; Intestinal Mucosa; Lung; Mast Cells; Nasal Provocation Tests; Prostaglandin D2; Prostaglandins D; SRS-A; Time Factors

Topics: Animals; Catechols; Histamine Release; Humans; Hypersensitivity; Indomethacin; Lung; Masoprocol; Mast Cells; Prostaglandin D2; Prostaglandins D; SRS-A

The effect of PGE2 and PGD2 on several lymphocyte functions in vitro was evaluated in nonatopic and atopic subjects. Both PGE2 and PGD2 inhibited phytohemagglutinin-induced protein synthesis ([3H] leucine uptake) by nonatopic mononuclear cells and T cells in a dose-dependent manner (10(-6) to 10(-12) M). Protein synthesis by atopic mononuclear cells was not significantly suppressed by the above concentration of PGE2. Although PGD2 effectively suppressed protein synthesis by atopic mononuclear cells and T cells at 10(-6) M, lower concentrations were ineffective. Kinetic studies revealed significant differences in the suppressive effects of PGE2 and PGD2 on atopic and nonatopic mononuclear cells at 24 and 48 h, but not at 72 or 96 hr. Protein synthesis by T helper-enriched populations (suppressor cell depletion by anti-Leu-2b + complement) obtained from nonatopics was significantly reduced by PGE2 and PGD2, suggesting that these mediators may be directly inhibiting the responding population. By contrast, protein synthesis by T suppressor-enriched populations (helper cell depletion by OKT4 + complement) obtained from nonatopics was enhanced by PGE2 and PGD2, suggesting that the PG were activating these cells. Atopic T helper and T suppressor cells exhibited decreased responsiveness to PGE2 and PGD2 compared with nonatopic cells. PGE2 and PGD2 inhibited the phytohemagglutinin-stimulated proliferative response ([3H]thymidine uptake) by both atopic and nonatopic mononuclear cells in a dose-dependent manner and to the same extent. However, although PGE2 and PGD2 generated functional suppressor activity (when using a coculture technique) in nonatopic mononuclear cells, these mediators failed to activate atopic suppressor cells. These results suggest that reduced responses by atopic T cells to signals provided by PGE2 and PGD2 are not solely restricted to suppressor cell function, and could indicate an impaired ability to regulate immune and/or inflammatory reactions.

Topics: Dinoprostone; DNA; Dose-Response Relationship, Drug; Humans; Hypersensitivity; Immune Tolerance; Lymphocyte Activation; Monocytes; Prostaglandin D2; Prostaglandins D; Prostaglandins E; Protein Biosynthesis; T-Lymphocytes; T-Lymphocytes, Helper-Inducer; T-Lymphocytes, Regulatory

Topics: Adult; Allergens; Asthma; Bronchial Spasm; Humans; Hypersensitivity; Male; Prostaglandin D2; Prostaglandins D; Pulmonary Alveoli; Skin Tests

Topics: Bee Venoms; Bronchial Provocation Tests; Clinical Trials as Topic; Dust; Histamine; Humans; Hypersensitivity; Immunoglobulin E; Mites; Nasal Provocation Tests; Peptide Hydrolases; Poaceae; Pollen; Prostaglandin D2; Prostaglandins D; Skin Tests; Tissue Extracts

Prostaglandin D2 is a secondary mast cell mediator that causes redness, chemosis, mucous discharge, and eosinophil chemotaxis in the eye. It may play an important role in allergic ocular disease. Although histamine is a key mediator of allergic inflammation, antihistamine therapy provides only symptomatic relief. We added aspirin therapy to the treatment regimen of three patients with vernal conjunctivitis. Aspirin acetylates the enzyme cyclooxygenase, thereby preventing the formation of prostaglandin D2. Within two weeks after initiation of aspirin therapy, we noted dramatic improvement in conjunctival and episcleral redness and resolution of keratitis and limbal infiltration. We recommend a trial of oral aspirin as adjunctive therapy for intractable cases of vernal conjunctivitis.

Topics: Adolescent; Aspirin; Child; Conjunctivitis; Female; Histamine; Humans; Hypersensitivity; Male; Mast Cells; Prostaglandin D2; Prostaglandins D; Seasons; Urticaria Pigmentosa

Topics: Basophils; Histamine; Humans; Hypersensitivity; Immunity, Cellular; Immunoglobulin E; In Vitro Techniques; Inflammation; Mast Cells; Prostaglandin D2; Prostaglandins; Prostaglandins D