Anterior chamber-associated immune deviation induced by soluble antigens

Immune responses to cellular antigens placed in the anterior chamber of the eye are deviant: antibodies and cytotoxic T cells are generated, but delayed hypersensitivity is impaired. To determine whether a similar pattern of unusual reactivity would be induced by soluble antigens placed in this privileged site, we have examined the systemic immune responses of mice to anterior chamber injections of bovine serum albumin and bovine retinal S antigen - both soluble molecules. Recipients of intraocular injections of these antigens without adjuvant developed no detectable systemic immune response. When BSA was mixed with complete or incomplete Freund's adjuvant and injected into the anterior chamber, recipients produced serum specific antibodies; however, they displayed impaired delayed hypersensitivity. Anterior chamber recipients of soluble antigens subsequently proved refractory to the development of delayed hypersensitivity when immunogenic doses of the same antigens were placed subcutaneously. Moreover, the inability to mount delayed hypersensitivity could be adoptively transferred with spleen cells from animals that had previously received intraocular injections of bovine albumin or S antigen. It is concluded that soluble antigens, as well as surface membrane-bound antigens, are capable of inducing anterior chamber-associated immune deviation (ACAID). The possibility is discussed that the capacity of soluble retinal S antigen to induce ACAID may be pertinent to the maintenance of self-tolerance to this autologous, intraocular molecule.