INCREASED MESSENGER-RNA EXPRESSION OF IL-6, IL-10, TNF-ALPHA, AND PERFORIN IN BLOOD MONONUCLEAR-CELLS IN HUMAN HIV-INFECTION

Evidence has been presented for the involvement of various cytokines, including interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-a lpha, in the pathogenesis of human immunodeficiency virus (HIV) infect ion. Since measured plasma levels may poorly reflect in vivo productio n of cytokines, we adopted in situ hybridization with cDNA oligonucleo tide probes to enumerate blood mononuclear cells (MNCs) expressing mRN A for IL-6, IL-10, TNF-alpha, and perforin. The HIV-infected patients had elevated levels of MNCs expressing mRNA for all four cytokines com pared to healthy controls. Numbers of IL-6 mRNA-expressing cells were higher in patients with clinical AIDS than in asymptomatic seropositiv e patients, and correlated inversely with CD4(+) cell counts in blood, reflecting the involvement of IL-6 in later stages of HIV infection. The described approach could be an alternative way to study cytokines in HIV infection.