Objectives: To examine the relation of circulating cytokines and cytokine antagonists to the progression of human immunodeficiency virus type 1 (HIV-1) disease.
Design: Cross-sectional analysis.
Setting: An ambulatory acquired immunodeficiency syndrome (AIDS) research clinic in Kinshasa, Zaire.
Patients: 48 women with AIDS, 51 women with HIV infection who were clinically asymptomatic, and 11 female controls who did not have HIV infection, all from Zaire.
Measurements: Plasma levels of interleukin-1 β, tumor necrosis factor-α (TNF-α), interleukin-6, interleukin-8, interferon-γ, interleukin-1 β receptor antagonist (interleukin-1Ra), and TNF soluble receptor p55 (TNFsRp55) were assayed by specific radioimmunoassays. Plasma levels of interferon-γ were assayed by commercial enzyme-linked immunosorbent assay. The Wilcoxon rank-sum test was used to assess the significance of mean and median differences between groups.
Results: Of the 48 patients with AIDS, circulating interleukin-1 β was detected in 2, TNF-α in 4, interleukin-6 in 3, and interleukin-8 in 12. None of these factors were seen in any of the 11 controls. Median values of interleukin-1 β (320 pg/mL), TNF-α (210 pg/mL), and interleukin-8 (750 pg/mL) were elevated in HIV-infected asymptomatic patients compared with patients with AIDS (2-, 2.6-, and 18.7-fold higher, respectively; P < 0.001). Interleukin-1Ra and TNFsRp55 levels were substantially higher than interleukin-1 β and TNF-α levels in HIV-infected asymptomatic patients (73- and 14-fold, respectively) and were higher than those in patients with AIDS (17.8- and 1.74-fold, respectively).
Conclusion: High circulating levels of the proinflammatory cytokines interleukin-1 β and TNF-α, combined with an excess of their natural inhibitors interleukin-1Ra and TNF-sRp55, were seen in clinically asymptomatic HIV-1-positive African women but not in African women with AIDS or in HIV-negative controls. Circulating cytokine antagonists may play a clinical role in modulating cytokine-associated symptoms in the early phases of HIV infection.