CD4 and HIV infectious disease: Findings of correlate-of-risk studies done after the RV144 results were released in 2009 indicated that a reduced risk of HIV infection was associated with higher levels of binding antibodies to HIV env (total IgG and IgG3) and antibodies to scaffolded antigens, including the V1V2 loop.10, 13, 19 High CD4+ T-cell functionality and polyfunctionality scores to HIV-1 env antigens were also associated with decreased risk of HIV infection.12