TLR4 and infection: The results revealed distinct temporal expression profiles of Toll-like receptors (TLRs), showing that TLR2, TLR4, TLR7 and TLR10 were significantly upregulated in a parabolic pattern, with TLR2 and TLR10 peaking at 36 h while TLR4 and TLR7 reached maximum expression at 24 h post-infection (Figure 6a).