Lymphocyte subpopulations and S-antigen reactivity in retinitis pigmentosa

The lymphocyte subpopulations in the peripheral blood of 37 patients with retinitis pigmentosa (RP) and 24 controls were analyzed with the Leu series of monoclonal antibodies in conjunction with fluorescence-activated cell-sorter analysis. The peripheral blood lymphocytes (PBLs) from all RP genetic types had a significantly reduced frequency of Leu-4-positive T lymphocytes than controls, and a small but significant reduction in the frequency of Leu-3a-positive T lymphocytes was seen in patients with RP with the dominant trait. The reduced T-cell population seemed to be associated with an increased frequency of Leu-11a-positive cells. The PBLs from patients with RP did not react to retinal S-antigen, as assessed by the lymphocyte transformation or interleukin-2 assays. We conclude that patients with RP, although not clinically immunologically compromised, have a significantly reduced frequency of T lymphocytes in their PBLs. Furthermore, our study did not demonstrate reactivity to retinal tissue in PBLs from patients with RP.