Cellular immunity in patients with acquired immunodeficiency syndrome (AIDS) in Israel: effects of THF, a thymic hormone in vitro.

Markers and functions of T cell subsets were studied in 3 Israeli males suffering from AIDS, two of whom were homosexuals and one heterosexual developing AIDS after a coronary bypass operation followed by multiple blood transfusions. Two healthy homosexual partners of one of the AIDS patients were also studied. Sera from these individuals were also tested for suppressive activity on control normal donor lymphocytes. Monitoring of T-cell subsets during a period of 3-12 months demonstrated a reversed T helper: T suppressor ratio in the 3 AIDS patients and in one of the healthy homosexuals. Addition of AIDS sera to normal T helper cells abolished the helper activity whereas its addition to normal isolated T suppressor cells enhanced the suppressor activity. Incubation of the patients lymphocytes with THF, a calf thymus hormone, restored the impaired helper cell activity. A suppressor factor unrelated to acid labile interferon was demonstrated in the sera of the AIDS patients but was not found in the sera of the healthy homosexuals. THF neutralized the suppressor effect of this serum factor when tested on normal lymphocytes.