TNF and infection: Although differences in the TNF responses between TIGR4 and TIGR4 Δcps strains were lost after infection of TLR2−/− macrophages (Fig. 9A and B), the TIGR4 and TIGR4 Δcps strains both stimulated a TLR2 reporter assay to a similar degree and purified serotype 4 capsular polysaccharide (PPS) had no effect (Fig. 9C).