Adaptation to promiscuous usage of CC and CXC-chemokine coreceptors in vivo correlates with HIV-1 disease progression

Abstract
To study coreceptor usage of sequential primary HIV-1 isolates in a longitudinal follow-up cohort of HIV-1-infected men to understand its contribution to pathogenesis of HIV disease. Viral coreceptor usage of sequential primary isolates from HIV-1-infected individuals was examined at various timepoints and data was compared with CD4 cell counts, rates of disease progression and β-chemokine production. Fifty-eight sequential primary isolates were obtained from four rapid progressors, six late progressors, and three long-term nonprogressors (LTNP) and their coreceptor usage was examined by infection of peripheral blood mononuclear cells (PBMC) from donors with wild-type or non-functional CC-chemokine receptor (CCR)-5, and by infection of GHOST4 cells expressing CD4 and various chemokine receptors [CCR-1–CCR-5, CXC-chemokine receptor (CXCR)-4, BOB/GPR15, BONZO/STRL33]. Production of RANTES and macrophage inflammatory protein (MIP)-1β was examined using unstimulated or phytohemagglutinin (PHA)-stimulated PBMC isolated from these individuals at multiple timepoints during infection. A switch from single CCR-5 coreceptor usage to multiple coreceptor usage occurred in all four rapid progressors and three out of six late progressors. In addition to the commonly used coreceptors CXCR-4, CCR-5, and CCR-3, some of the viruses isolated from patients in the terminal stage of infection also used CCR-1, CCR-2b, CCR-4, and BOB as coreceptors. The emergence of viral variants capable of utilizing multiple coreceptors generally preceded CD4 cell decline to 6 Viral variants capable of utilizing a broad range of coreceptors correlated with HIV-1 disease progression. In contrast, LTNP maintain exclusive usage of CCR-5 and produce higher levels of β-chemokines. Thus, both viral and host determinants leading to the emergence of viral variants capable of using an expanded range of coreceptors may be likely determinants of disease progression.