Regulation of chemokine/cytokine network during in vitro differentiation and HIV-1 infection of human monocytes: possible importance in the pathogenesis of AIDS

The monocyte/macrophage lineage represents heterogeneous cell populations c haracterized by major differences in the phenotype and functional activitie s. These cells are a major source of soluble factors, such as cytokines and chemokines, which can both affect HIV replication and AIDS pathogenesis. A lthough monocytes/macrophages are unanimously considered important targets of HIV-1 infection, the HIV-induced alterations in their physiological func tions at different stages of differentiation are still matter of debate. In this article, we review our data on the regulation of chemokine/cytokine n etwork with regard to macrophage differentiation and HIV-1 infection, in co mparison with studies from other groups. The ensemble of the results emphas izes that: 1) macrophages markedly differ with respect to monocytes for a v ariety of responses potentially important in the pathogenesis of HIV infect ion; and 2) the experimental conditions can influence the HIV-monocyte/macr ophage interactions, reflecting the possible in vivo existence of a spectru m of responses among macrophage populations.