Relationship of Plasma HIV-RNA Levels and Levels of TNF-α and Immune Activation Products in HIV Infection

Abstract

The goal of this study was to determine the relationship between plasma human immunodeficiency virus (HIV) load and cytokine expression. HIV-RNA plasma levels were determined in 34 HIV-seropositive (HIV+) asymptomatic subjects [range: 0.5 to 211 kiloequivalents (kEq)/ml HIV-RNA], by a modified branched-DNA (bDNA) assay. Plasma HIV-RNA levels were positively correlated with increased plasma levels of TNF-α, soluble TNF receptor type II, soluble IL-2 receptor, β2-microglobulin, and neopterin, but not with plasma IL-6 levels. In contrast, increased viral load and diminished CD4 counts correlated weakly. TNF-α mRNA levels, as determined by bDNA technology, were not significantly increased in peripheral blood mononuclear cells (PBMC) isolated from HIV-infected subjects, compared to HIV-seronegative (HIV−) subjects, and were not correlated with plasma levels of HIV-RNA, cytokines, or activation markers. These results are consistent with the hypothesis that a self-reinforcing mechanism exists between TNF-α production and generalized immune activation on one hand with HIV replication on the other.