SUMMARY
To investigate the relationship between uveitis and HTLV‐I infection, we examined the crossreactivity between HTLV‐I antigens and retinal antigens recognized by T cells in BIO.BR mice immunized with human HTLV‐I‐infected MT‐2 cells. We found that T cells obtained from MT‐2 immune mouse spleen responded not only to HTLV‐I antigens but also to retinal antigens of various species. However, they did not respond to HTLV‐I‐negative lymphoid cell lines. Furthermore, established T cell lines from MT‐2 immune spleen cells also responded to both HTLV‐I and retinal antigens. The phenotype of the immune cells that responded to both HTLV‐I and retinal antigens was CD4+, CD8‐, and CD3+. The proliferative response of T cell lines to HTLV‐I as well as various retinal antigens, was clearly blocked by addition of anti‐CD3, anti‐CD4, or anti‐I‐AK MoAbs, but not by anti‐CD8 antibody. The established T cell lines from HTLV‐I immune spleen cells were all found to be CD3+, TCRβ+, CD4+, CD8‐ cells by flow cytometric analysis. These results indicate that an epitope of HTLV‐I antigens is cross‐reactive to an epitope of retinal antigens extracted from either human retinoblastoma or normal murine, rat, and bovine retinae at a T cell recognition level.