TLR2 and infection: However, the bacterial killing assay showed that C29 treatment did not significantly affect bactericidal function at earlier time points (1 h and 4 h), but decreased bacterial killing rate and increased bacterial burden in BMDMs after 12 h of infection (Figs 5E and S6B), indicating that TLR2 signaling is critical for bacterial killing activity of macrophages after persistent S. aureus infection.