Interleukin-2 production by persons with the generalized lymphadenopathy syndrome or the acquired immune deficiency syndrome.

We measured production of interleukin-2 (IL-2) by phytohemagglutinin-stimulated peripheral blood mononuclear cells from 27 heterosexual persons, 43 asymptomatic homosexual men, 34 homosexual men with generalized lymphadenopathy syndrome (GLS), and 21 patients with acquired immune deficiency syndrome (AIDS). Asymptomatic heterosexual and homosexual subjects produced comparable amounts of IL-2, but 8 of 11 AIDS patients with opportunistic infections and two of three AIDS patients with both opportunistic infections and Kaposi's sarcoma failed to produce detectable amounts of IL-2; all seven AIDS patients with only Kaposi's sarcoma produced IL-2. The titer of IL-2 produced by the AIDS patients correlated with the percentage of helper T lymphocytes (Leu 3a+ cells) but not with the percentage of suppressor T lymphocytes (Leu 2a+ cells). This observation is interpreted as indicating that failure to produce IL-2 by AIDS patients is most likely due to depletion of IL-2-producing cells, although an abnormality of T-cell function has not been excluded. In addition, three of eight AIDS patients who did not produce IL-2 produced supernatants that inhibited growth of IL-2-dependent cells in the presence of IL-2. These observations suggest that measurement of endogenous IL-2 production may be important in selecting patients for therapy with IL-2.