Specificity of the in Vitro Immune Response to Synthetic Polypeptide Antigens in Inbred Rats

Abstract

The immune response to a variety of synthetic and natural antigens is under the control of genes present within the major histocompatibility complex (MHC), and many of the responses are mediated by thymus-derived lymphocytes (1–3). These immune response (Ir) genes may code for cell-surface structures that are capable of specific antigen recognition, either by direct interaction with the antigen or by conformational changes in association with other cell surface structures (1, 2). The specificity of the proposed Ir gene product on the T cell has been examined by comparing the cross-reactivities of antibodies and of sensitized cells elicited by immunization with branched synthetic polypeptide antigens. McDevitt and his co-workers have presented evidence that the in vitro recognition of antigen by T cells in the mouse is more specific than either antibody cross-reactivity or antigen binding by B cells (4, 5). Similar results were obtained in the rat by comparing the cross-reactions of anti-polypeptide antibodies and the in vitro antigen-induced proliferative response (6).