Figure 2: HIV-1-specific IgG does not contribute to HIV inhibition.
(A) A series of immuno-capture techniques purified IgG from HIV-infected ART-suppressed EV-free plasma and EVs (n=4). (B) Concentration of purified IgG was measured by IgG-specific ELISA. IgG purification from HIV-infected ART-suppressed unfractionated serum was used as controls. (C) HIV-1 infectivity measured by incubation of 100,000RLU HIV-1 NL4.3 virus with purified and depleted IgG fractions, IgG controls, or vehicle PBS on TZM-bl cells for 24 h. Infectivity was measured by TZM-bl luciferase reporter activity. Vehicle treated cells are set as reference at 100% for infectivity (broken line). Statistics was determined by comparing infectivity values from all donors to vehicle control for each IgG fraction. Significance was determined by student’s t test. *=P<0.05, **=P<0.01, ***=P<0.001. Error bars are SD of biological replicates from the mean of triplicate measurements. ns= not significant.