leukotriene-b4 and Respiratory-Tract-Infections

Topics: Animals; B-Lymphocytes; Humans; Immunoglobulin A; Immunoglobulin E; Leukotriene B4; Mast Cells; Respiratory Hypersensitivity; Respiratory Tract Infections; T-Lymphocytes

Respiratory infection with Francisella tularensis (Ft) is characterized by a muted, acute host response, followed by sepsis-like syndrome that results in death. Infection with Ft establishes a principally anti-inflammatory environment that subverts host-cell death programs to facilitate pathogen replication. Although the role of cytokines has been explored extensively, the role of eicosanoids in tularemia pathogenesis is not fully understood. Given that lipoxin A

Topics: Acute Disease; Animals; Apoptosis; Arachidonate 5-Lipoxygenase; Bone Marrow Cells; Cell Death; Chemokines; Chronic Disease; Dinoprostone; Disease Susceptibility; Down-Regulation; Francisella tularensis; Immunity; Indoles; Inflammation Mediators; Leukotriene B4; Lipoxins; Macrophages; Metabolome; Mice, Inbred C57BL; Organ Specificity; Respiratory Tract Infections; Tularemia

The clinical and molecular effects of whole-body polarized light treatment on children suffering from recurrent respiratory infection were studied.. The incidence and duration of respiratory symptoms as well as the length of appropriate antibiotic therapy were measured. Simultaneously, the genome-wide gene expression pattern was examined by whole genome cDNA microarray in peripheral lymphocytes of children.. Twenty of 25 children showed a marked clinical improvement, while in five of 25 had poor response or no changes. The gene expression pattern of the patients' peripheral lymphocytes was compared in favorable and poor responders. The lymphocytes of the children with a documented improved clinical response to polarized light therapy showed a decrease in the expression of chemokine genes, such as CXCL1, CXCL2, CXCL3, and IL-8, and in that of the TNFα gene. On the contrary, a rapid elevation was found in the expression of the gene encoding for CYP4F2, a leukotriene B4-metabolizing enzyme. In children with poor clinical response to polarized light therapy, no similar changes were detected in the gene expression pattern of the lymphocytes.. The improved clinical symptoms and modified gene expression profile of lymphocytes reveals an anti-inflammatory effect of whole-body polarized light irradiation.

Topics: Anti-Inflammatory Agents; Chemokines; Child; Child, Preschool; Female; Gene Expression; Genome-Wide Association Study; Genome, Human; Humans; Infant; Inflammation; Leukotriene B4; Light; Lymphocytes; Male; Oligonucleotide Array Sequence Analysis; Recurrence; Respiration; Respiration Disorders; Respiratory Tract Infections

Topics: Animals; Biomarkers; Breath Tests; Dog Diseases; Dogs; Female; Leukotriene B4; Male; Respiratory Tract Infections

The clinical and immunoregulatory effects of long-term macrolide antibiotic therapy for patients with chronic lower respiratory tract infections (CLRTI) were investigated. Clinical parameters and neutrophil chemotactic mediators in the epithelial lining fluid (ELF) of CLRTI patients (n = 10) were examined before and after 3 months oral administration of roxithromycin (RXM). The in vitro effects of RXM were also examined on the release of these mediators from alveolar macrophages (AM) and neutrophils. Arterial oxygen tension (p<0.05), vital capacity (VC) (p<0.001), %VC (p<0.05) and forced expiratory volume in one second (p<0.01) were improved after RXM treatment, but airway bacteria were not eradicated. Among the mediators, the levels of interleukin (IL)-8, neutrophil elastase (NE) and leukotriene B4 (LTB4) were higher in ELF than in plasma of CLRTI patients and they decreased after RXM treatment (n = 7, p<0.05 for each). RXM concentrations were significantly increased in the bronchoalveolar lavage cells of the treated patients. In in vitro experiments, RXM showed inhibitory effects on IL-8 release from AM and neutrophils. In conclusion, interleukin-8, neutrophil elastase and leukotriene B4 contribute to the neutrophilic inflammation in the airways of chronic lower respiratory tract infection patients and the clinical effects of roxithromycin may, in part, be attributable to the suppression of excess release of the chemotactic mediators from inflammatory cells.

Topics: Anti-Bacterial Agents; Bronchiectasis; Bronchiolitis; Bronchoalveolar Lavage Fluid; Chemotactic Factors; Chronic Disease; Forced Expiratory Volume; Humans; In Vitro Techniques; Interleukin-8; Leukocyte Elastase; Leukotriene B4; Macrophages, Alveolar; Middle Aged; Neutrophils; Oxygen; Respiratory Tract Infections; Roxithromycin; Vital Capacity

Patients with homozygous (PiZ) alpha(1)-antitrypsin (AAT) deficiency have not only low baseline serum AAT levels (approximately 10 to 15% normal) but also an attenuated acute phase response. They are susceptible to the development of premature emphysema but may also be particularly susceptible to lung damage during bacterial exacerbations when there will be a significant neutrophil influx. The purposes of the present study were to assess the inflammatory nature of acute bacterial exacerbations of chronic obstructive pulmonary disease (COPD) in subjects with AAT deficiency, to compare this with COPD patients without deficiency, and to monitor the inflammatory process and its resolution following appropriate antibacterial therapy. At the start of the exacerbation, patients with AAT deficiency had lower sputum AAT (p < 0.001) and secretory leukoprotease inhibitor (SLPI; p = 0.02) with higher elastase activity (p = 0.02) compared with COPD patients without deficiency. Both groups had a comparable acute phase response as assessed by C-reactive protein (CRP) but the AAT-deficient patients had a minimal rise in serum AAT (to < 6 microM). After treatment with antibiotics, in patients with AAT deficiency, there were significant changes in many sputum proteins including a rise in SLPI levels, and a reduction in myeloperoxidase (MPO) and elastase activity (p < 0. 005 for all measures); the sputum chemoattractants interleukin-8 (IL-8) and leukotriene B(4) (LTB(4)) fell (p < 0.01), and protein leak (sputum/serum albumin ratio) became lower (p < 0.01). The changes were rapid and within 3 d of the commencement of antibiotic therapy the biochemical markers had decreased significantly, but took a variable time thereafter to return to baseline values. In conclusion, patients with AAT deficiency had evidence of increased elastase activity at the start of the exacerbation when compared with nondeficient COPD patients which probably reflects a deficient antiproteinase screen (lower sputum AAT and SLPI). The increased bronchial inflammation at presentation resolved rapidly with 14 d of antibiotic therapy.

Topics: Acute Disease; Acute-Phase Reaction; Aged; alpha 1-Antitrypsin; alpha 1-Antitrypsin Deficiency; Bacterial Infections; Bronchi; C-Reactive Protein; Female; Humans; Inflammation Mediators; Interleukin-8; Leukotriene B4; Lung Diseases, Obstructive; Male; Middle Aged; Pancreatic Elastase; Peroxidase; Phenotype; Proteinase Inhibitory Proteins, Secretory; Proteins; Respiratory Tract Infections; Secretory Leukocyte Peptidase Inhibitor; Serine Proteinase Inhibitors; Serum Albumin; Sputum

In order to evaluate the role of polymorphonuclear leukocytes (PMNs) in acute otitis media (AOM), levels of leukotriene B4 (LTB4), a potent inflammatory product of PMNs, and interleukin-8 (IL-8), a PMN chemotactic cytokine, were measured in 271 middle ear fluid (MEF) samples from 106 children with AOM. Forty-two percent of the patients had evidence of respiratory viral infection. At the time of diagnosis, levels of both LTB4 and IL-8 were higher in the MEFs from patients with AOM associated with bacterial or bacterial and viral infection than those MEFs containing no pathogen (p < .05). Antibiotic treatment was not associated with a significant change in levels of LTB4 or IL-8 in the MEFs obtained 2 to 5 days into treatment, compared to those obtained at diagnosis. Bacteriologic failure after 2 to 5 days of treatment was associated with high LTB4 levels in the initial MEFs (p = .05). Recurrence of AOM within 1 month was associated with high IL-8 levels in the initial MEF (p = .04). Our findings suggest that LTB4 and IL-8 are produced during acute infection of the middle ear, and these PMN-related inflammatory substances may play an important role in delaying recovery or in recurrence of AOM. Effective treatment of AOM may require eradication of bacteria by antibiotics, as well as pharmacologic agents that modulate PMN functions.

Topics: Bacterial Infections; Enzyme-Linked Immunosorbent Assay; Female; Humans; Infant; Interleukin-8; Leukotriene B4; Male; Neutrophils; Otitis Media; Recurrence; Respiratory Tract Infections; Virus Diseases

Mediator release was examined from superficially lying cells in the airway epithelium obtained by bronchoalveolar lavage (BAL) in 13 non-atopic individuals. The BAL-cells were incubated (20 min, 37 degrees C) with Staphylococcus (Staph.) aureus or with human influenza A virus Staph. aureus was found to release histamine from cells from 7 of the 13 individuals and influenza A virus in 3 of 5 persons. Furthermore, Staph, aureus stimulated the BAL-cells to release leukotriene B4 in 7 of 11 subjects, whereas no release was found by influenza A virus in 7 examined persons. When cells from 4 persons were stimulated with Staph. aureus no release of leukotriene C4 was found. The mediator release caused by bacteria and virus might be of importance for the exacerbation of bronchial asthma in upper respiratory tract infections, since histamine is assumed to increase the epithelial permeability with entrance of allergens and other insulting particles, and leukotriene B4 facilitates airway inflammation.

Topics: Adult; Aged; Asthma; Female; Histamine Release; Humans; In Vitro Techniques; Influenza A virus; Leukotriene B4; Leukotrienes; Male; Middle Aged; Respiratory System; Respiratory Tract Infections; SRS-A; Staphylococcus aureus