S100B and infection: Peak levels of plasma viremia were observed at 2 weeks pi and were highly similar in WT and CD3ko-Nef SIVmac239 infection (29.5 × 106 ± 8.5 × 106 versus 22.2 × 106 ± 7.1 × 106; mean viral RNA (vRNA) copies/mL ± SEM; Figure 2A).