NT5E and HIV infectious disease: Since SIV/HIV infections promote T-cell immune activation (8, 30), we then evaluated the effect of early ARV initiation on T-cell immune activation by assessing the expression of HLA-DR and CD39, an ectonucleotidase that converts ATP into immunosuppressive adenosine in concert with CD73, both known as markers of T-cell activation (13, 31, –, 33).