S100B and infection: THP-1/PMA macrophages were infected with vesicular stomatitis virus G glycoprotein–pseudotyped (VSV-G–pseudotyped) single-cycle HIV-1 encoding GFP as a reporter in place of nef (LaiΔenvGFP/G) (Figure 1A), and proinflammatory cytokine CXCL10 (IP-10) secretion in infected cultures was employed as a quantitative measure of infection-induced innate immune activation.