Splenic T cells from mice receiving intracameral antigen suppress in-vitro antigen-induced proliferation and interferon-? production by sensitized lymph node cells

Abstract

Purpose: To characterize the immunoregulatory mechanisms in vitro of spleen cells that are activated by intracameral injection of antigen (AC-spleen cells). Methods: AC-spleen cell regulation of in-vitro antigen-induced proliferation and interferon-? production by lymph node cells from TNP-BSA-immunized mice was quantified by co-culture of the lymph node cells with TNP-BSA and AC-spleen cells induced by intracameral TNP-BSA. Cytokine production was quantified by ELISA. Results: AC-spleen cells produced significantly more IL-4 and IL-10 than spleen cells from TNP-BSA-immunized mice or naive spleen cells; unlike spleen cells from immunized mice, AC-spleen cells did not produce IFN-?. AC-splenic CD4 + , CD8 + , CD4 - /CD8 - (DN) T cells differentially suppressed antigen-induced proliferation and IFN-? production by immunized lymph node cells by a mechanism dependent on IL-10 and antigen. Cultures of lymph node cells, antigen, and AC-splenic T cells contained increased amounts of IL-10 and/or TGFß2. Conclusions: The differential, cytokinedependent immunoregulatory effects of CD4 + and CD8 + AC-spleen cells observed in vitro parallel their effects in vivo. We suggest that the suppression of antigen-induced lymphocyte proliferation and IFN-? production by AC-spleen cells provides a useful in-vitro assay of the immunoregulatory activity of cell populations that are induced by the injection of antigen into the anterior chamber.