The use of synthetic peptides in the delineation of immunoglobulin antigenic epitopes and Fc effector functions.
As an alternative strategy to the use of proteolytic and chemical cleavage in the production of fragments of immunoglobulins retaining Fc effector functions, peptides representative of amino acid sequences constituting the putative active sites have been synthesized and assessed for biological activity in various in vitro systems. This approach has been adopted in attempts to define more precisely the autoantigenic epitope on human IgG against which anti-gamma-globulin antibodies (the so-called general 'rheumatoid factors'), found in the sera and joint fluids of patients with rheumatoid arthritis, are directed. Synthetic peptides representative of epsilon-chain sequences are being used in the production of antibodies (polyclonal and monoclonal) directed against specific epitopes within the Fc regions of human and rat IgE. The ability of these antisera to influence the in vitro functional properties of IgE anaphylactic antibodies is now under investigation, with particular attention being focused on cytophilicity and mast cell triggering. Preliminary findings suggest that certain of the antisera might be capable of inhibiting mast cell sensitization by IgE antibodies, and therefore might form the basis of a new type of anti-allergy compound.
D000818:Animals; D001324:Autoantigens / Q000276:immunology; D000939:Epitopes / Q000276:immunology; D006801:Humans; D007141:Immunoglobulin Fc Fragments / Q000276:immunology*; D007128:Immunoglobulin Fragments / Q000276:immunology*; D007074:Immunoglobulin G / Q000276:immunology; D007143:Immunoglobulin Heavy Chains / Q000276:immunology; D007139:Immunoglobulin epsilon-Chains / Q000276:immunology; D008407:Mast Cells / Q000276:immunology; D010455:Peptides / Q000138:chemical synthesis / Q000276:immunology*; D012217:Rheumatoid Factor / Q000276:immunology
D001324:Autoantigens; D000939:Epitopes; D007141:Immunoglobulin Fc Fragments; D007128:Immunoglobulin Fragments; D007074:Immunoglobulin G; D007143:Immunoglobulin Heavy Chains; D007139:Immunoglobulin epsilon-Chains; D010455:Peptides; D012217:Rheumatoid Factor