In Vitro Effects of Immunosuppressive Agents on Cytokine Production by HTLV‐I‐Infected T Cell Clones Derived from the Ocular Fluid of Patients with HTLV‐I Uveitis

The present study was designed to investigate the in vitro effects of potential therapeutic agents on cytokine production by five HTVL-I-infected T cell clones (TCC) established from the ocular fluid of patients with HTLV-I uveitis. Each of the five HTLV-I-infected TCC was cultured at 1 x 10(6) cells/ml with or without an immunosuppressive agent (hydrocortisone, FK506, rapamycin, indomethacin, or prostaglandin E2) for 22 hr in humidified 5% CO2 in air at 37 C. The production of various cytokines in the culture supernatant from each TCC was measured by ELISA. The HTLV-I-infected TCC produced high amounts of IL-1 alpha, IL-3, IL-6, IL-8, TNF-alpha, IFN-gamma, and GM-CSF, and low but significant levels of IL-2 and IL-10 without any stimuli. Hydrocortisone severely depressed the production by these TCC of all the cytokines except for IL-2, which was slightly increased. Prostaglandin E2 depressed the production of IL-1 alpha, while it up-regulated the production of IL-6, TNF-alpha, and IFN-gamma. Rapamycin depressed the production of IL-6 and TNF-alpha, and FK506 depressed the production of TNF-alpha. Hydrocortisone also severely depressed the cytokine production by PHA-stimulated peripheral blood mononuclear cells obtained from healthy volunteers. Of the immunosuppressive agents tested, hydrocortisone exhibited the strongest suppression of cytokine production by HTLV-I-infected TCC. This result was in agreement with the in vivo effects of hydrocortisone in patients with HTLV-I uveitis. These TCC will be useful in investigating the effects of potential therapeutic agents for HTLV-I uveitis in vitro.