Cellular immune function of patients with retinitis pigmentosa.

Although initial investigations of peripheral blood lymphocytes (PBL) from patients with retinitis pigmentosa (RP) demonstrated a reduced percentage of Leu-4 positive (pan-T) lymphocytes, the authors recently determined that the absolute number of Leu-4 positive cells per milliliter of blood is normal. This investigation studied the production of the lymphokines gamma-interferon (gamma-IFN) and interleukin-2 (IL-2) in cultures of concanavalin-A stimulated PBL. The difference in the mean production of gamma-IFN or IL-2 by PBL from 33 RP patients versus PBL from 16 controls did not achieve statistical significance at P less than 0.05. Overall, the data did not demonstrate significant cellular immune abnormalities in patients with RP.