FIG 5.

Negative controls for neutralization using 1:50-diluted serum. (A) Residual infectivity of the MLV Env pseudovirus in the TZM-bl cell assay using all vaccinated monkey serum samples diluted 1:50, organized by trial (M19, M21, M22) and the time of sample collection (week 40/41 or 58), as indicated. The medians for all of the groups shown ranged from 98% to 108% residual infectivity. Of the 246 serum-Env combinations analyzed, 15 fell between 80% and 90% residual infectivity (6%) and 1 fell below 80% residual infectivity (0.4%). (B) Residual infectivity of a pool of naive rhesus macaque monkey serum diluted 1:50 against the global panel of reference Envs, the SHIV1137ipd3N4 Env, and the MLV Env. The monkey serum pool was included in each set of serum samples (see the heat maps in Fig. 8) according to the trial (M19, M21, M22) and the time of sample collection (weeks 40/41 and 58). Thus, the pool was run 6 times against each Env. The median residual infectivity for the HIV-1 Envs ranged from 96.5% to 109.5%. Of the 78 naive pooled serum–HIV-1 Env combinations analyzed, only 2 fell below 90% residual infectivity (2.5%).