Angiogenic and HIV-Inhibitory Functions of KSHV-Encoded Chemokines

Unique among known human herpesviruses, Kaposi's sarcoma-associated herpesvirus (KSHV or HHV-8) encodes chemokine-like proteins (vMIP-I and vMIP-II). vMIP-II was shown to block infection of human immunodeficiency virus-type 1 (HIV-1) on a CD4-positive cell line expressing CCR3 and to a lesser extent on one expressing CCR5, whereas both vMIP-I and vMIP-II partially inhibited HIV infection of peripheral blood mononuclear cells. Like eotaxin, vMIP-II activated and chemoattracted human eosinophils by way of CCR3. vMIP-I and vMIP-II, but not cellular MIP-1alpha or RANTES, were highly angiogenic in the chorioallantoic assay, suggesting a possible pathogenic role in Kaposi's sarcoma.