Expression of chemokine receptors on natural killer cells in HIV-infected individuals

Chemokine receptors CCR5 and CXCR4 are of major importance in the pathogenesis of HIV-1 infection because they are co-receptors for human immunodeficiency virus (HIV) entry. We examined the frequency of CD3−CD56+CCR5+ and CD3−CD56+CXCR4+ in HIV-infected long-term slow progressors (SPs), HIV typical progressors (TPs) with or without highly active antiretroviral therapy (HAART), and HIV-seronegative controls. The results showed that the frequency of CD3−CD56+CCR5+ was up-regulated, and frequency of CD3−CD56+CXCR4+ was down-regulated in HAART–naïve HIV TPs group compared with HIV SPs group and HIV-seronegative controls (P < 0.05). The frequency of CD3−CD56+CCR5+ was down-regulated by HAART therapy (P < 0.05). The frequency of CD3−CD56+CCR5+ was lower in HIV SPs compared with controls (P < 0.05). Lower frequency of CD3−CD56+CXCR4+ and higher frequency of CD3−CD56+CCR5+ positively correlated with the level of HIV viral loads and negatively correlated with CD4 T cell counts (P < 0.05). These results indicated that the expression of chemokine receptors on NK cells correlated with HIV disease progression.