g(m1)-ganglioside and Inflammation

Topics: Anemia, Hemolytic; Animals; Chemical and Drug Induced Liver Injury; Female; G(M1) Ganglioside; Hepatomegaly; Immunization, Passive; Inflammation; Interleukin-2; Killer Cells, Lymphokine-Activated; Macaca fascicularis; Male; Mice; Mice, Inbred C57BL; Mice, SCID; Pulmonary Edema; Pulmonary Eosinophilia; Rats; Receptors, Interleukin-1; Recombinant Proteins; Severe Combined Immunodeficiency; Splenomegaly; Tumor Necrosis Factor-alpha; Viscera

The purpose of this review was to summarize observations on the type and function of inflammatory infiltrates of mouse mammary tumors and to speculate on the underlying mechanisms and the significance of infiltrates to mammary tumor biology. Although the major conclusion is that much more work is needed, certain themes seem to be emerging. The number of infiltrating cells can be very high but is unrelated to biological behavior of the tumors. What seems to be important is the relative contributions of inflammatory cell subsets. In the case of T-cell subsets and NK cells, the infiltrates from tumors of long-term cell lines so far seem uninformative. The general characteristics are similar to those of infiltrates from rapidly proliferating, normal mammary tissues. These characteristics do not correlate with diverse biological behavior or malignant potential. A more informative model appears to be one in which the development of tumors from preneoplastic tissue can be observed. Here our attention is currently focused on NK cells. By contrast, the correlation between activated TAM and metastatic behavior suggests that our transplantable MMT lines may be biologically relevant in the study of infiltrating macrophages. We are especially interested in the role of TAM in the generation of tumor cell variability. Overall, our data indicate that the host infiltrate is another manifestation of both inter- and intra-tumor heterogeneity and, as such, is not simply a response to, but, rather, a part of the tumor ecosystem. Unraveling the cellular and molecular mechanisms that govern the inflammatory cell component of tumors should provide insight into the types of cellular interactions that result in tumor development and progression.

Topics: Animals; Antigens, Differentiation, T-Lymphocyte; Antigens, Surface; Cell Adhesion; Cell Movement; Chemotaxis, Leukocyte; G(M1) Ganglioside; Glycosphingolipids; Immunity, Cellular; Immunity, Innate; Inflammation; Killer Cells, Natural; Lymphocyte Activation; Macrophages; Mammary Glands, Animal; Mammary Neoplasms, Experimental; Precancerous Conditions; T-Lymphocytes

Neuro-inflammation and activated microglia play important roles in neuron damage in the traumatic brain injury (TBI). In this study, we determined the effect of neural network reconstruction after human umbilical cord mesenchymal stem cells (UMSCs) combined with monosialotetrahexosy 1 ganglioside (GM1) transplantation and the effect on the neuro-inflammation and polarization of microglia in a rat model of TBI, which was established in male rats using a fluid percussion brain injury device. Rats survived until day 7 after TBI were randomly treated with normal control (NC), saline (NS), GM1, UMSCs, and GM1 plus UMSCs. Modified neurological severity score (mNSS) was assessed on days 7 and 14, and the brain tissue of the injured region was collected. Immunofluorescence, RT-PCR, and western blot analysis found that inhibitory neuro-inflammatory cytokines TGF-β and CD163 protein expression levels in injured brain tissues were significantly increased in rats treated with GM1 + UMSCs, GM1, or UMSCs and were up-regulated compared to saline-treated rats. Neuro-inflammatory cytokines IL-6, COX-2 and iNOS protein expressions were down-regulated compared to rats treated with saline. The protein expression levels of NE, NF-200, MAP-2 and β-tubulin III were increased in the injured brain tissues from rats treated with GM1 + UMSCs, or GM1 and UMSCs alone compared to those in the rats treated with NS. The protein expression levels in rats treated with GM1 plus UMSCs were most significant on day 7 following UMSC transplantation. The rats treated with GM1 plus UMSCs had the lowest mNSS compared with that in the other groups. These data suggest that UMSCs and GM1 promote neural network reconstruction and reduce the neuro-inflammation and neurodegeneration through coordinating injury local immune inflammatory microenvironment to promote the recovery of neurological functions in the TBI.

Topics: Animals; Brain Injuries, Traumatic; Cytokines; G(M1) Ganglioside; Gangliosides; Humans; Inflammation; Male; Mesenchymal Stem Cells; Neuroinflammatory Diseases; Rats; Umbilical Cord

Gangliosides are glycosphingolipids highly enriched in the brain, with important roles in cell signaling, cell-to-cell communication, and immunomodulation. Genetic defects in the ganglioside biosynthetic pathway result in severe neurodegenerative diseases, while a partial decrease in the levels of specific gangliosides was reported in Parkinson's disease and Huntington's disease. In models of both diseases and other conditions, administration of GM1-one of the most abundant gangliosides in the brain-provides neuroprotection. Most studies have focused on the direct neuroprotective effects of gangliosides on neurons, but their role in other brain cells, in particular microglia, is not known. In this study we investigated the effects of exogenous ganglioside administration and modulation of endogenous ganglioside levels on the response of microglia to inflammatory stimuli, which often contributes to initiation or exacerbation of neurodegeneration.. In vitro studies were performed using BV2 cells, mouse, rat, and human primary microglia cultures. Modulation of microglial ganglioside levels was achieved by administration of exogenous gangliosides, or by treatment with GENZ-123346 and L-t-PDMP, an inhibitor and an activator of glycolipid biosynthesis, respectively. Response of microglia to inflammatory stimuli (LPS, IL-1β, phagocytosis of latex beads) was measured by analysis of gene expression and/or secretion of pro-inflammatory cytokines. The effects of GM1 administration on microglia activation were also assessed in vivo in C57Bl/6 mice, following intraperitoneal injection of LPS.. GM1 decreased inflammatory microglia responses in vitro and in vivo, even when administered after microglia activation. These anti-inflammatory effects depended on the presence of the sialic acid residue in the GM1 glycan headgroup and the presence of a lipid tail. Other gangliosides shared similar anti-inflammatory effects in in vitro models, including GD3, GD1a, GD1b, and GT1b. Conversely, GM3 and GQ1b displayed pro-inflammatory activity. The anti-inflammatory effects of GM1 and other gangliosides were partially reproduced by increasing endogenous ganglioside levels with L-t-PDMP, whereas inhibition of glycolipid biosynthesis exacerbated microglial activation in response to LPS stimulation.. Our data suggest that gangliosides are important modulators of microglia inflammatory responses and reveal that administration of GM1 and other complex gangliosides exerts anti-inflammatory effects on microglia that could be exploited therapeutically.

Topics: Animals; Anti-Inflammatory Agents; Cells, Cultured; Dioxanes; G(M1) Ganglioside; Humans; Inflammation; Interleukin-1beta; Lipopolysaccharides; Mice; Microglia; Phagocytosis; Pyrrolidines; Rats

GM1 gangliosidosis (GM1) is an autosomal recessive disorder characterized by the deficiency of beta-galactosidase (β-gal), a ubiquitous lysosomal enzyme that catalyzes the hydrolysis of GM1 ganglioside.. The study aims to explore the application of the AAV9-coGLB1 for effective treatment in a GM1 gangliosidosis mutant mouse model.. We designed a novel adeno-associated virus 9 (AAV9) vector expressing β-gal (AAV9- coGLB1) to treat GM1 gangliosidosis. The vector, injected via the caudal vein at 4 weeks of age, drove the widespread and sustained expression of β-gal for up to 32 weeks in the Glb1. The increased levels of β-gal reduced the pathological damage occurring in GM1 mice. Histological analyses showed that myelin deficits and neuron-specific pathology were reduced in the cerebral cortex region of AAV9-coGLB1-treated mice. Immunohistochemical staining showed that the accumulation of GM1 ganglioside was also reduced after gene therapy. The reduction of the storage in these regions was accompanied by a decrease in activated microglia. In addition, AAV9 treatment reversed the blockade of autophagic flux in GM1 mice.. These results show that AAV9-coGLB1 reduces the pathological signs of GM1 gangliosidosis in a mouse model.

Topics: Animals; Central Nervous System; Dependovirus; Disease Models, Animal; G(M1) Ganglioside; Gangliosidosis, GM1; Inflammation; Lysosomes; Mice

Among the pathological events associated with the dopaminergic neurodegeneration characteristic of Parkinson's disease (PD) are the accumulation of toxic forms of α-synuclein and microglial activation associated with neuroinflammation. Although numerous other processes may participate in the pathogenesis of PD, the two factors mentioned above may play critical roles in the initiation and progression of dopamine neuron degeneration in PD. In this study, we employed a slowly progressing model of PD using adeno-associated virus-mediated expression of human A53T α-synuclein into the substantia nigra on one side of the brain and examined the microglial response in the striatum on the injected side compared to the non-injected (control) side. We further examined the extent to which administration of the neuroprotective ganglioside GM1 influenced α-synuclein-induced glial responses. Changes in a number of microglial morphological measures (i.e., process length, number of endpoints, fractal dimension, lacunarity, density, and cell perimeter) were indicative of the presence of activated microglial and an inflammatory response on the injected side of the brain, compared to the control side. In GM1-treated animals, no significant differences in microglial morphology were observed between the injected and control striata. Follow-up studies showed that mRNA expression for several inflammation-related genes was increased on the A53T α-synuclein injected side vs. the non-injected side in saline-treated animals and that such changes were not observed in GM1-treated animals. These data show that inhibition of microglial activation and potentially damaging neuroinflammation by GM1 ganglioside administration may be among the many factors that contribute to the neuroprotective effects of GM1 in this model and possibly in human PD.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Dopamine; G(M1) Ganglioside; Inflammation; Microglia; Parkinson Disease; Rats; Substantia Nigra

Neuroinflammation is involved in the pathology and progression of Alzheimer's disease (AD) and is closely related to microglial activation. We have previously reported that cattle encephalon glycoside and ignotin (CEGI) could inhibit the activation of microglia in APP/PS1 mice, a mouse model of familial AD. However, the anti-neuroinflammatory mechanisms of CEGI have not yet been fully elucidated. Here, we aimed to investigate the role of CEGI in microglia-mediated neuroinflammation in AD. APP/PS1 mice were treated with CEGI intraperitoneally for 30 days, and then their cognition was assessed. We showed that CEGI alleviated cognitive damage with higher nesting scores, preferential indices, and spontaneous alternation rates in APP/PS1 mice. Moreover, CEGI treatment effectively reduced microglial activation and Iba-1 levels in the cortex of APP/PS1 mice. Additionally, CEGI decreased pro-inflammatory factors production and neuroinflammation-mediated neuronal damage in vivo and in vitro. Finally, CEGI upregulated BDNF levels and downregulated TLR4 and p-NF-κB p65 levels in vivo and in vitro. Taken together, these findings indicated that CEGI could attenuate cognitive deficits in APP/PS1 mice and suppress microglia-induced neuroinflammation via increasing BDNF expression and inhibiting the TLR4/NF-κB pathway.

Topics: Alzheimer Disease; Animals; Brain-Derived Neurotrophic Factor; Carnosine; Cattle; Cell Line, Tumor; Cerebral Cortex; Cytokines; Female; G(M1) Ganglioside; Humans; Inflammation; Male; Mice, Inbred C57BL; Mice, Transgenic; Microglia; Neurons; Neuroprotective Agents; NF-kappa B p50 Subunit; Signal Transduction; Toll-Like Receptor 4

High altitude cerebral edema (HACE) is a severe type of acute mountain sickness (AMS) that occurs in response to a high altitude hypobaric hypoxic (HH) environment. GM1 monosialoganglioside can alleviate brain injury under adverse conditions including amyloid-β-peptide, ischemia and trauma. However, its role in HACE-induced brain damage remains poorly elucidated. In this study, GM1 supplementation dose-dependently attenuated increase in rat brain water content (BWC) induced by hypobaric chamber (7600 m) exposurefor 24 h. Compared with the HH-treated group, rats injected with GM1 exhibited less brain vascular leakage, lower aquaporin-4 and higher occludin expression, but they also showed increase in Na+/K+-ATPase pump activities. Importantly, HH-incurred consciousness impairment and coordination loss also were ameliorated following GM1 administration. Furthermore, the increased oxidative stress and decrease in anti-oxidant stress system under the HH condition were also reversely abrogated by GM1 treatment via suppressing accumulation of ROS, MDA and elevating the levels of SOD and GSH. Simultaneously, GM1 administration also counteracted the enhanced inflammation in HH-exposed rats by muting pro-inflammatory cytokines IL-1β, TNF-α, and IL-6 levels in serum and brain tissues. Subsequently, GM1 potentiated the activation of the PI3K/AKT-Nrf2 pathway. Cessation of this pathway by LY294002 reversed GM1-mediated inhibitory effects on oxidative stress and inflammation, and ultimately abrogated the protective role of GM1 in abating brain edema, cognitive and motor dysfunction. Overall, GM1 may afford a protective intervention in HACE by suppressing oxidative stress and inflammatory response via activating the PI3K/AKT-Nrf2 pathway, implying a promising agent for the treatment of HACE.

Topics: Altitude; Altitude Sickness; Animals; Brain Edema; G(M1) Ganglioside; Inflammation; Male; Neuroprotective Agents; NF-E2-Related Factor 2; Oxidative Stress; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Signal Transduction

It is known that exogenous gangliosides (GL) inhibit acute inflammatory signals in different cells induced by Escherichia coli lipopolysaccharide (LPS). Until now the mechanisms underlying their effect are unknown. We hypothesize that the anti-inflammatory effect of GL is caused by their ability to modify TLR4 translocation into the lipid rafts. To test this hypothesis, we studied the effect of exogenous GL on LPS-induced inflammatory reactions associated with increased nitric oxide and prostaglandin E2 (PGE2) production in epithelial cells isolated from the frog Rana temporia urinary bladder. It was shown that preincubation of cells with GM1 and GD1a in the concentration range from 100 nm to 50 μM reduced the effect of 25 μg/ml LPS E. coli on the increase of NO and PGE2 production. The effect of LPS was also eliminated in the presence of polymyxin B, capable to interact with lipid A in LPS molecule, which makes it inaccessible for binding to TLR4. The subcellular fractionation of epithelial cells in the sucrose density gradient in combination with immunoblotting revealed that LPS stimulates translocation of TLR4 into the lipid rafts in the cytoplasmic membrane. Preincubation of cells with GM1 or GD1a at concentration 20 μM completely eliminated the effect of LPS. A similar effect was revealed with 1 mM methyl-β-cyclodextrin, a classical destructor of the lipid rafts. The results indicate the existence of a previously unknown mechanism of the anti-inflammatory effect of exogenous GL associated with their ability to interfere with LPS-induced translocation of TLR4 into the lipid rafts preventing LPS signal transduction. It is assumed that the observed effect of GL is based on their incorporation into cytoplasmic membrane and modification of the lipid rafts organization.

Topics: Animals; Cells, Cultured; Epithelial Cells; G(M1) Ganglioside; Gangliosides; Inflammation; Lipopolysaccharides; Rana temporaria

Converging evidence shows that GD3 ganglioside is a critical effector in a number of apoptotic pathways, and GM1 ganglioside has neuroprotective and noötropic properties. Targeted deletion of GD3 synthase (GD3S) eliminates GD3 and increases GM1 levels. Primary neurons from GD3S-/- mice are resistant to neurotoxicity induced by amyloid-β or hyperhomocysteinemia, and when GD3S is eliminated in the APP/PSEN1 double-transgenic model of Alzheimer's disease the plaque-associated oxidative stress and inflammatory response are absent. To date, no small-molecule inhibitor of GD3S exists. In the present study we used sialidase from Vibrio cholerae (VCS) to produce a brain ganglioside profile that approximates that of GD3S deletion. VCS hydrolyzes GD1a and complex b-series gangliosides to GM1, and the apoptogenic GD3 is degraded. VCS was infused by osmotic minipump into the dorsal third ventricle in mice over a 4-week period. Sensorimotor behaviors, anxiety, and cognition were unaffected in VCS-treated mice. To determine whether VCS was neuroprotective in vivo, we injected kainic acid on the 25th day of infusion to induce status epilepticus. Kainic acid induced a robust lesion of the CA3 hippocampal subfield in aCSF-treated controls. In contrast, all hippocampal regions in VCS-treated mice were largely intact. VCS did not protect against seizures. These results demonstrate that strategic degradation of complex gangliosides and GD3 can be used to achieve neuroprotection without adversely affecting behavior.

Topics: Animals; Anxiety; G(M1) Ganglioside; Gene Deletion; Inflammation; Kainic Acid; Memory; Mice; Motor Activity; Nerve Degeneration; Neuraminidase; Neuroprotective Agents; Neurotoxins; Sialyltransferases; Skull; Vibrio cholerae

Evidence suggests that NK and NKT cells contribute to inflammation and mortality during septic shock caused by cecal ligation and puncture (CLP). However, the specific contributions of these cell types to the pathogenesis of CLP-induced septic shock have not been fully defined. The goal of the present study was to determine the mechanisms by which NK and NKT cells mediate the host response to CLP. Control, NK cell-deficient, and NKT cell-deficient mice underwent CLP. Survival, cytokine production, and bacterial clearance were measured. NK cell trafficking and interaction with myeloid cells was also studied. Results show that mice treated with anti-asialoGM1 (NK cell deficient) or anti-NK1.1 (NK/NKT cell deficient) show less systemic inflammation and have improved survival compared with IgG-treated controls. CD1 knockout mice (NKT cell deficient) did not demonstrate decreased cytokine production or improved survival compared with wild type mice. Trafficking studies show migration of NK cells from blood and spleen into the inflamed peritoneal cavity where they appear to facilitate the activation of peritoneal macrophages (F4-80(+)GR-1(-)) and F4-80(+)Gr-1(+) myeloid cells. These findings indicate that NK but not CD1-restricted NKT cells contribute to acute CLP-induced inflammation. NK cells appear to mediate their proinflammatory functions during septic shock, in part, by migration into the peritoneal cavity and amplification of the proinflammatory activities of specific myeloid cell populations. These findings provide new insights into the mechanisms used by NK cells to facilitate acute inflammation during septic shock.

Topics: Abdomen; Animals; Antigens, CD1; Antigens, Ly; Antigens, Surface; Cell Movement; G(M1) Ganglioside; Immunoglobulin G; Inflammation; Killer Cells, Natural; Lectins, C-Type; Macrophages, Peritoneal; Mice; Mice, Inbred BALB C; Mice, Knockout; NK Cell Lectin-Like Receptor Subfamily B; Shock, Septic; T-Lymphocytes

Intradermal (i.d.) immunization is a promising route of vaccine administration. Suitable i.d. adjuvants are important to increase vaccine efficacy in poorly responding populations such as the elderly or for dose-sparing strategies in the face of vaccine shortages. Bacterial exotoxins, such as Escherichia coli heat-labile enterotoxin (LT), exert strong immunostimulatory effects through binding to monosialoganglioside (GM1) cell surface receptors; however, injection is hampered by local inflammation. We demonstrate that the injection of LT formulations deficient in GM1 binding by mutation (LT(G33D)) or in vitro ligand coupling does not cause localized edema and inflammation in mice, yet these formulations retain potent adjuvant activity by enhancing functional Ab and cellular immune responses to coadministered Ags. Complete protection against in vivo lethal tetanus toxin challenge and the induction of Ag-specific CTL responses capable of killing target cells in vivo indicated in vivo efficacy of the induced immune responses. LT(G33D) proved superior to standard alum adjuvant regarding the magnitude and breadth of the induced immune responses. Immunizations in complex ganglioside knockout mice revealed a GM1-independent pathway of LT adjuvanticity. Immunostimulation by i.d. LT(G33D) is explained by its ability to induce migration of activated APCs to the proximal draining lymph nodes. LT(G33D) is a promising candidate adjuvant for human trials of parenteral vaccines in general and for current i.d. vaccine development in particular.

Topics: Adjuvants, Immunologic; Alum Compounds; Animals; Antibodies, Bacterial; Antigen-Presenting Cells; Bacterial Toxins; Cell Line, Tumor; Cell Movement; Cytotoxicity, Immunologic; Enterotoxins; Escherichia coli Proteins; Exotoxins; Female; G(M1) Ganglioside; Inflammation; Injections, Intradermal; Lymph Nodes; Melanoma, Experimental; Mice; Mice, Inbred C3H; Mice, Inbred C57BL; Mice, Knockout; N-Acetylgalactosaminyltransferases; Protein Binding; T-Lymphocytes, Cytotoxic; Tetanus; Tetanus Toxoid

Natural killer (NK) cells have a well-established role in host defense against viral infections and malignancies. However, their function in bacterial infection and sepsis is poorly defined. We hypothesized that NK cells, as a major producer of interferon-gamma during sepsis, would be important in host defense against bacterial infections. Cecal ligation and puncture (CLP) was performed on Swiss Webster mice depleted of NK cells by pretreatment with anti-asialo GM1 and control mice given immunoglobulin G (IgG) antibody. NK cell-depleted mice had significantly higher anaerobic bacterial counts in the liver and peritoneal lavage fluid, as well as higher aerobic counts in the liver and blood 4 h after CLP. Macrophage phagocytosis, nitric oxide production, and interleukin (IL)-6 levels at 4 h were also decreased in mice depleted of NK cells compared with controls. Greater neutrophil influx into the peritoneum, indicated by higher myeloperoxidase levels, was also seen in NK cell-depleted mice. At 8 and 18 h after CLP, bacterial counts were similar between groups, and overall survival rates were not significantly different. Peritoneal IL-12 levels significantly increased by 18 h in normal mice, but not in NK cell-depleted animals. Our data suggest that NK cells participate in the early local and systemic eradication of bacteria and regulation of IL-12 during polymicrobial sepsis. These effects are likely due to their interactions with macrophages.

Topics: Animals; Bacteria; Cell Movement; Chemokine CXCL2; Flow Cytometry; G(M1) Ganglioside; Inflammation; Interleukin-6; Killer Cells, Natural; Macrophages; Mice; Monokines; Neutrophils; Nitric Oxide; Peritonitis; Peroxidase; Phagocytosis; Sepsis; Time Factors

beta 2 microglobulin knockout (beta2M-/-) mice lack CD8+ T and natural killer T cells. We hypothesized that beta 2M-/- mice are resistant to lethal intraabdominal sepsis. To test this hypothesis, mortality, cytokine production, and physiologic function were assessed in beta 2M-/- mice during sepsis caused by cecal ligation and puncture (CLP). beta 2M-/- mice survived significantly longer than wild-type mice after CLP but ultimately exhibited 100% mortality. Treatment of beta 2M-/- mice with anti-asialoGM1 to deplete natural killer cells conferred greater than 70% long-term survival. Compared with wild-type mice, beta 2M-/- mice treated with anti-asialoGM1 produced decreased amounts of proinflammatory cytokines and did not exhibit hypothermia or metabolic acidosis after CLP. Adoptive transfer of CD8+ T and natural killer cells into beta 2M-/- mice treated with anti-asialoGM1 re-established CLP-induced mortality. CD8 knockout mice treated with anti-asialoGM1, which are specifically deficient in CD8+ T and natural killer cells, exhibited 40% long-term survival after CLP. Furthermore, treatment of wild-type mice with antibodies to CD8 and asialoGM1 conferred a significant survival benefit compared with wild-type mice treated with nonspecific IgG. These findings demonstrate that beta 2M-/- mice treated with anti-asialoGM1 are resistant to CLP-induced mortality and that depletion of CD8+ T and natural killer cells largely accounts for the survival benefit observed in these mice.

Topics: Adoptive Transfer; Animals; beta 2-Microglobulin; CD8-Positive T-Lymphocytes; Cecum; Disease Models, Animal; Female; G(M1) Ganglioside; Immunity, Innate; Inflammation; Killer Cells, Natural; Ligation; Lymphopenia; Mice; Mice, Inbred C57BL; Mice, Knockout; Peritonitis; Sepsis; Survival Analysis

Much of the pulmonary disease in cystic fibrosis is associated with polymorphonuclear leukocyte-dominated airway inflammation caused by bacterial infection. Respiratory epithelial cells express the polymorphonuclear chemokine interleukin-8 (IL-8) in response to ligation of asialylated glycolipid receptors, which are increased on damaged or regenerating cells and those with cystic fibrosis transmembrane conductance regulator mutations. Because both Pseudomonas aeruginosa and Staphylococcus aureus, the most common pathogens in cystic fibrosis, bind asialylated glycolipid receptors such as asialoGM1, we postulated that diverse bacteria can activate a common epithelial signaling pathway to elicit IL-8 expression. P. aeruginosa PAO1 but not pil mutants and S. aureus RN6390 but not the agr mutant RN6911 stimulated increases in [Ca(2+)](i) in 1HAEo- airway epithelial cells. This response stimulated p38 and ERK1/2 mitogen-activated protein kinase (MAPK) signaling cascades resulting in NF-kappaB activation and IL-8 expression. Ligation of the asialoGM1 receptor or thapsigargin-elicited Ca(2+) release activated this pathway, whereas P. aeruginosa lipopolysaccharide did not. The rapid kinetics of epithelial activation precluded bacterial invasion of the epithelium. Recognition of asialylated glycolipid receptors on airway epithelial cells provides a common pathway for Gram-positive and Gram-negative organisms to initiate an epithelial inflammatory response.

Topics: Adhesins, Bacterial; Blotting, Western; Calcium; Cell Line; Cystic Fibrosis; Cystic Fibrosis Transmembrane Conductance Regulator; Egtazic Acid; Enzyme Activation; Epithelial Cells; G(M1) Ganglioside; Genes, Reporter; Humans; Inflammation; Interleukin-8; Kinetics; Lipopolysaccharides; Luciferases; Lung; MAP Kinase Signaling System; Microscopy, Fluorescence; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Mitogen-Activated Protein Kinases; Mutation; NF-kappa B; Pseudomonas aeruginosa; Receptors, Cell Surface; Signal Transduction; Spectrophotometry; Staphylococcus aureus; Thapsigargin; Time Factors; Trachea

Pseudomonas aeruginosa strains are opportunistic pathogens associated with infections in immunocompromised hosts and patients with cystic fibrosis. Like many other mucosal pathogens, P. aeruginosa cells express flagella which provide motility and chemotaxis toward preferred substrates but also provide a ligand for clearance by phagocytic cells. We tested the role of flagella in the initial stages of respiratory tract infection by comparing the virulence of fliC mutants in a neonatal mouse model of pneumonia. In the absence of fliC, there was no mortality, compared with 30% mortality attributed to the parental strain PAK or 15% mortality associated with infection due to a pilA mutant PAK/NP (P < 0.0001). The fliC mutants caused pneumonia in only 25% of the mice inoculated, regardless of whether there was expression of the pilus, whereas the parental strain was associated with an 80% rate of pneumonia. Histopathological studies demonstrated that the fliC mutants caused very focal inflammation and that the organisms did not spread through the lungs as seen in infection due to either PAK or PAK/NP. Purified flagellin elicited an intense inflammatory response in the mouse lung. 125I-labeled flagellin bound to the glycolipids GM1 and GD1a and to asialoGM1 in an in vitro binding assay. However, flagellin-mediated binding to epithelial gangliosides was a relatively unusual event, as quantified by binding assays of wild-type or fliC mutant organisms to CHO Lec-2 cells with membrane-incorporated GM1. Fla+ organisms but not fliC mutants were efficiently taken up by murine macrophages. P. aeruginosa flagella are important in the establishment of respiratory tract infection and may act as a tether in initial interactions with epithelial membranes. This function is offset by the contribution of flagella to host clearance mechanisms facilitating phagocytic clearance and the role of flagellar genes in mucin binding and clearance.

Topics: Animals; Bacterial Adhesion; Bacterial Proteins; CHO Cells; Cricetinae; DNA-Binding Proteins; Fimbriae Proteins; Flagella; Flagellin; Flow Cytometry; G(M1) Ganglioside; Gangliosides; Inflammation; Macrophages; Mice; Mice, Inbred BALB C; Pneumonia, Bacterial; Pseudomonas aeruginosa; Pseudomonas Infections; Respiratory Tract Infections; Tumor Cells, Cultured; Virulence

Anti-ganglioside (anti-GM1) antibodies have been implicated in the pathogenesis of Guillain-Barré syndrome, multifocal motor neuropathy and motor neuron diseases. It has been held that they may interfere with saltatory conduction by blocking sodium channels. We tested this hypothesis by analysing action potentials from 140 single nerve fibres in 22 rat ventral roots using external longitudinal current measurement. High-titre anti-GM1 sera from Guillain-Barré syndrome or multifocal motor neuropathy patients, or anti-GM1 rabbit sera were applied to the rat ventral root, where saltatory conduction in single motor fibres was serially observed for 4-12 h (mean 8.2 h). For control experiments, we also tested anti-galactocerebroside (anti-GalC) sera, which causes acute demyelinative conduction block, and tetrodotoxin (TTX), a sodium channel blocker. Conduction block was found in 82% of the fibres treated with anti-GalC sera and 100% treated with TTX, but only in 2% (one out of 44) treated with the patients' sera and 5% (two out of 38) treated with rabbit anti-GM1 sera. All the nodes blocked by anti-GM1 sera revealed intense passive outward membrane current, in the internode just beyond the last active node. This pattern of current flow was similar to that in fibres blocked by demyelination with anti-GalC sera, and quite different from that seen in fibres blocked by reducing sodium currents with TTX. Our findings suggest that anti-GM1 sera neither mediate conduction block nor block sodium channels on their own. We conclude that physiological action of the antibody alone is insufficient to explain clinically observed conduction block in human diseases.

Topics: Action Potentials; Animals; Antibodies; Autoantibodies; Axons; G(M1) Ganglioside; Humans; Inflammation; Membrane Potentials; Motor Neuron Disease; Motor Neurons; Nerve Fibers; Neural Conduction; Polyradiculoneuropathy; Rabbits; Rats; Rats, Wistar; Sodium Channel Blockers; Spinal Nerve Roots; Tetrodotoxin

Unlike CNS myelin, human peripheral nerve myelin has the acidic glycosphingolipids sialosyl paragloboside (SPG), sialosyl lactosaminyl paragloboside (SLPG), and sulfated glucuronyl paragloboside (SGPG). To elucidate the pathogenesis of Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating neuropathy (CIDP), we investigated the autoantibodies to peripheral nerve molecules in patients with these diseases and compared the frequency of the autoantibodies with that of autoantibody to GM1 which is present in both the CNS and PNS. The report of Sheikh et al. (Ann. Neurol. 1995; 38: 350) that Campylobacter jejuni bears the SGPG epitope led us to study whether sera from patients with GBS subsequent to C. jejuni enteritis have anti-SGPG antibody; but, high anti-SGPG antibody titers were not found in the GBS patients from whom C. jejuni was isolated. Although the frequency of the anti-SPG, anti-SLPG and anti-SGPG antibodies were lower than that of the anti-GM1 antibody in GBS, 5 patients with demyelinating GBS had high IgG anti-SPG antibody titers. IgG anti-SPG antibody may function in the development of demyelinating GBS. We found that 6 CIDP patients had elevated IgM anti-SGPG antibody titers. Immunoelectrophoresis failed to detect IgM M-protein in 3 of the patients. IgM anti-SGPG antibody could be a diagnostic marker for a subgroup of CIDP with or without paraprotein.

Topics: Aged; Antibody Specificity; Antigens, Bacterial; Autoantibodies; Autoantigens; Autoimmune Diseases; Biomarkers; Campylobacter jejuni; Carbohydrate Sequence; Chronic Disease; Cross Reactions; Demyelinating Diseases; Epitopes; Female; G(M1) Ganglioside; Globosides; Humans; Immunoelectrophoresis; Immunoglobulin G; Immunoglobulin M; Inflammation; Lipopolysaccharides; Male; Middle Aged; Molecular Mimicry; Molecular Sequence Data; Peripheral Nerves; Polyradiculoneuropathy

Gangliosides (GA) have been shown to promote axonal sprouting and growth of injured peripheral nerves, and enhance functional biochemical and morphologic recovery after CNS damage. Moreover, it has recently been shown that the natural ganglioside mixture (GM1 + GD1a + GD1b + GT1b) from bovine brain is endowed with powerful anti-inflammatory activity in rodents. Here we report that the novel semisynthetic ganglioside derivative AGF44, the isopropyl ester of monosialoganglioside GM1, displays a potent anti-inflammatory activity when orally or topically administered in various models of acute inflammation. AGF44 was effective (0.5-5 mg/kg p.o. or 0.5% gel topical application) in reducing rat paw oedema induced by either carrageenin, histamine, bradykinin, serotonin, nystatin or kaolin. Moreover, crossed confrontation with the effects elicited by other anti-inflammatory agents revealed that AGE44 seems to act through a different pathway than NSAIDs, steroids or antihistaminic/antiserotoninic agents.

Topics: Administration, Oral; Administration, Topical; Animals; Anti-Inflammatory Agents, Non-Steroidal; Drug Evaluation, Preclinical; G(M1) Ganglioside; Inflammation; Male; Mice; Peritonitis; Rats; Rats, Sprague-Dawley

The induction of severe inflammatory process and fatal neurological disease by transfer of lymphocytic choriomeningitis virus (LCMV)-immune T cells into cyclophosphamide (Cy)-suppressed LCMV-infected mice is greatly inhibited by treatment of these recipients with antibody to the asialo GM1 ganglioside (anti-ASGM1). Examination of cytotoxic activity in lymphoid tissue of the Cy-suppressed recipients at 72 hr after cell transfer revealed that anti-ASGM1 treatment prevented the development of the cytotoxic T lymphocyte (CTL) response, even though the dose of antibody used did not significantly decrease CTL generation in unsuppressed mice. Abrogation of CTL activity was also observed following antibody treatment of NK-deficient (bg/bg) Cy-suppressed recipients, indicating that the anti-ASGM1 was unlikely to be operating via removal of NK cells that are in some way involved in the development of the CTL response. The possibility that anti-ASGM1 may act directly on T cells should be considered in all protocols involving the use of this reagent in immunosuppressed mice.

Topics: Animals; Cytotoxicity, Immunologic; G(M1) Ganglioside; Glycosphingolipids; Immunity, Cellular; Immunization, Passive; Inflammation; Killer Cells, Natural; Lymphocytic Choriomeningitis; Mice; T-Lymphocytes, Cytotoxic

The inflammatory exudate found in cerebrospinal fluid (CSF) of mice 6 days after intracerebral infection with lymphocytic choriomeningitis virus (LCMV) contains substantial populations of both cytotoxic T lymphocytes (CTL) and natural killer (NK) cells. Removal of NK cell activity by in vivo treatment with antibody to the asialo GM1 ganglioside and studies with NK-deficient bg/bg mice did not clearly determine whether NK cells contribute in any way to the development of clinical LCM. However, the LCM disease process induced in cyclophosphamide-suppressed, LCMV-infected recipients by the adoptive transfer of LCMV-immune spleen cells occurs in the absence of NK cell effector function in spleen, lymph nodes, or CSF of the recipients, though potent CTL populations are present in all of these sites. In this situation, NK cells are apparently not required for the induction of neurological symptoms that are indistinguishable from those of classical LCM.

Topics: Animals; Antigens, Ly; Cerebrospinal Fluid; Cyclophosphamide; Cytotoxicity, Immunologic; G(M1) Ganglioside; Glycosphingolipids; Immunity, Innate; Immunization, Passive; Immunosuppression Therapy; Inflammation; Killer Cells, Natural; Lymph Nodes; Lymphocytic Choriomeningitis; Mice; Mice, Mutant Strains; Spleen; T-Lymphocytes, Cytotoxic; Time Factors

We have characterized the major glycolipid constituents of the mouse peritoneal macrophage, and have demonstrated that alterations in the amount and in the accessibility of specific glycolipid species to galactose oxidase/NaB3H4 labeling, an indicator of glycolipid surface exposure, occur in response to inflammation and as a consequence of activation to a tumoricidal state. The key findings are: (a) Asialo GM1, a major neutral glycolipid constituent of all macrophage populations examined, is accessible to galactose oxidase/NaB3H4 labeling on the surface of TG-elicited and BCG-activated macrophages but not on resident macrophages; (b) GM1 is the predominant ganglioside constituent of the mouse macrophage. Resident macrophages contain two distinct GM1 species, as determined by cholera toxin binding, while TG-elicited and BCG-activated macrophages contain an additional GM1 species. Differences in the relative amounts of these GM1 species, as well as in their accessibility to galactose oxidase/NaB3H4 labeling, exist among the macrophage populations. These observations suggest that both a chemical and spatial reorganization of surface glycolipids occurs in response to inflammation and tumoricidal activation.

Topics: Animals; Antigens, CD; Ascitic Fluid; Female; G(M1) Ganglioside; Galactosylceramides; Glycolipids; Glycosphingolipids; Inflammation; Lactosylceramides; Leukemia, Experimental; Macrophage Activation; Macrophages; Membrane Lipids; Mice; Mice, Inbred C57BL