Correlation of Spontaneous Suppressor Cell Activity with Progression of Human Immunodeficiency Virus Infection

The immune system has been extensively evaluated in the acquired immunodeficiency syndrome (AIDS). The central role of the T-helper (CD4) cell in the immunopathogenesis of AIDS and the immunologic markers that can predict human immunodeficiency virus (HIV) disease progression have been described. However, the potential influence of suppressor cells in this disease process has not been clearly addressed. Spontaneous suppressor cell activity (SSCA) was evaluated in 78 patients with documented HIV infection at different clinical stages of disease progression. Higher levels of SSCA were found in patients with clinical AIDS less than 6 months and those dying of AIDS when compared with controls. Significant elevations (p < 0.05) of SSCA were seen in patients newly diagnosed with AIDS, and those having AIDS greater than 6 months and less than one year. Patients surviving AIDS for greater than one year had depressed levels of SSCA compared to controls. Furthermore, SSCA appears to predict disease progression as patients with AIDS-related complex (ARC) with elevations in SSCA progressed to AIDS while those with blunted SSCA did not progress. The level of SSCA in these patients was able to predict disease progression (p = 0.00016, Pearson correlation coefficient = 0.739). Patients with documented AIDS were also followed prospectively, and the level of SSCA was shown to be predictive of mortality (p = 0.009, Pearson correlation coefficient = 0.746). It is concluded that SSCA is a valid predictor of disease progression, and can serve as a prognostic indicator of disease outcome.