title: Suppression of murine IgE responses with amino acid polymer/allergen conjugates. III. Activity in vitro.
abstract: Conjugates of poly-N-methylglycine (polysarcosine) and grass pollen allergen extracts, which have been previously shown to suppress murine IgE responses, were examined for their ability to modify lymphocyte activity in vitro. Allergen-specific T lymphocytes obtained from Balb/c mice gave a reduced response to syngeneic accessory cells pulsed with conjugates of polysarcosine-allergen compared with the response found using equivalent concentrations of native extract. Pretreatment of accessory cells with either polysarcosine or polysarcosine-allergen conjugates did not impair their subsequent ability to present grass pollen extract to immune T cells. Incubation of allergen-specific spleen cells with polysarcosine-allergen conjugates, but not with polysarcosine or allergen alone, resulted in specific cell-mediated suppression which significantly reduced proliferation in vitro. This activity was sensitive to treatment of cells with anti-T-lymphocyte antisera plus complement. Spleen cells obtained from animals immunised with allergen and taken 21 days after intravenous treatment with polysarcosine-allergen conjugates, a regimen that suppressed IgE antibody production, did not proliferate in the presence of grass pollen extract and failed to suppress a secondary lymphoproliferative response in vitro. Spleen cells obtained from similarly treated animals 3 days after the final polysarcosine-allergen injection responded to pollen extract in culture and, additionally, impaired a secondary response. The results suggest that the reduced IgE response found in animals treated with polysarcosine-allergen conjugates may be due, in part, to the generation of a short-lived antigen-specific T cell suppression.
mesh_terms: D000485:Allergens / Q000494:pharmacology*; D000818:Animals; D000938:Antigen-Presenting Cells / Q000166:cytology; D002478:Cells, Cultured; D007108:Immune Tolerance; D007073:Immunoglobulin E / Q000276:immunology*; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D008722:Methods; D051379:Mice; D010455:Peptides / Q000494:pharmacology*; D012521:Sarcosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D013154:Spleen / Q000166:cytology
chemical_list: D000485:Allergens; D010455:Peptides; C015475:polysarcosine; D007073:Immunoglobulin E; D012521:Sarcosine