CYTOKINE NETWORK AND ACUTE PRIMARY HIV-1 INFECTION

Objective: To investigate the relationship between cytokine serum leve ls, peripheral blood lymphocyte subsets and clinical picture in acute primary HIV-1 infection. Patients and methods: Absolute number/mul tot al lymphocytes, CD4+, CD8+ and natural killer (NK) cells, as well as s erum levels of soluble CD8 receptor, interleukin (IL)-1beta, IL-2, IL- 4, IL-6, tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma, b eta2-microglobulin and 5'-neopterin were determined in 15 patients wit h acute primary HIV-1 infection, 16 asymptomatic HIV-1-seropositive in dividuals and 18 HIV-1-seronegative individuals at risk for HIV-1 infe ction. Results: Acute primary HIV-1 infection was characterized by sig nificant CD4+ lymphocytopenia with low IL-2 serum concentrations, and by high absolute number of circulating CD8+ and NK cells, with elevate d serum levels of soluble CD8 receptor, IL-1beta, IFN-gamma and 5'-neo pterin. Follow-up of acute seroconverters showed a significant decreas e in NK cell counts and IL-1beta levels, with an increase of IL-6. Con clusions: In acute primary HIV-1 infection, significant alteration of cytokine release, possibly induced by viral antigens, could be respons ible for both clinical picture and activation of cytotoxic cells throu gh abnormal mechanisms.