Kaposi's sarcoma-associated herpesvirus (KSHV) chemokine vMIP-II and humanSDF-1 alpha inhibit signaling by KSHV G protein-coupled receptor

Kaposi's sarcoma-associated herpesvirus (KSHV) encodes two proteins that ar e similar to human CC chemokines and a G protein-coupled receptor (KSHV-GPC R) that is constitutively active. KSHV-GPCR binds a number of human CXC and CC chemokines. We showed that interferon gamma-inducible protein-10 (IP-10 ), a human CXC chemokine, inhibits KSHV-GPCR signaling (Geras-Raaka et al., J. Exp. Med. 188, 405-408, 1998). Here we show that viral monocyte inflamm atory protein-II (vMIP-II), one of the KSHV-encoded CC chemokines, and stro mal cell-derived factor 1 alpha (SDF-1 alpha), a human CXC chemokine that b locks infection by human immunodeficiency virus-type 1, inhibit KSHV-GPCR s ignaling also. If KSHV-GPCR signaling is involved in viral pathogenesis, th en these chemokines may affect the course of Kaposi's sarcoma and primary e ffusion lymphoma. (C) 1998 Academic Press.