Depressed Interleukin 2 Receptor Expression in Acquired Immune Deficiency and Lymphadenopathy Syndromes

Because interleukin 2 (IL 2) production and IL 2 receptor (IL 2R) expression are essential steps in T cell proliferation, we undertook to measure these parameters, as defects in one or both seemed likely to account for the reduced proliferative response to mitogen in acquired immune deficiency syndrome (AIDS) and lymphadenopathy syndrome (LAS). Reduced proliferative responses to PHA are a well established feature of AIDS with opportunistic infection (AIDS-OI), AIDS with Kaposi's sarcoma (AIDS-KS), and LAS patient groups. IL 2R expression was significantly reduced in both AIDS groups; a similar trend was observed with the LAS group. Mean levels of IL 2 in culture supernatants for the three patient groups, however, did not significantly differ from controls. IL 2R expression was significantly correlated with proliferation and the Th:Ts ratio in the AIDS-OI and LAS groups, and a good correlation between proliferation and the Th:Ts ratio was also observed. The AIDS-KS group, in contrast, showed no significant correlations between IL 2R expression, proliferation, or Th:Ts ratio. IL 2 levels did not correlate with any of these parameters in any of the patient groups. These findings indicated that poor T cell proliferative responses to mitogen (PHA) are intrinsically related to decreased IL 2R expression in AIDS-OI and LAS. In AIDS-KS, however, a statistically significant correlational relationship between these altered immune parameters is not apparent.