Inhibition of experimental autoimmune uveoretinitis in rats by S-antigen-specific monoclonal antibodies.

Mouse monoclonal antibodies (mAb), of either IgG2a or IgG2b isotypes, specific for the retinal S-autoantigen (S-Ag) or a pool of rat anti-S-Ag sera prevented experimental autoimmune uveoretinitis in Lewis rats when injected i.p. at the time of immunization. Control mAb of the same isotypes, irrelevant to S-Ag, had no inhibitory effect. The humoral response to S-Ag, as studied by enzyme-linked immunosorbent assay using a mouse mAb specific for rat kappa chain, was moderately but significantly reduced in suppressed animals. The rapid disappearance of the injected mAb from rat sera, as measured using a rat mAb specific for mouse kappa chain, could be explained by its complexing with either autologous antigen released from the retina at the site of inflammation, or anti-idiotypic antibodies.