Analysis of C5, C5aR1, and C5aR2 expression in the brain and liver at 24 h and 5 d post infection revealed no significant interaction between sex and bacterial infection, but there was a significant effect of bacterial infection on the expression of C5aR1 and C5aR2 in the liver 5 d post infection [F(1, 36) = 49.11, p < 0.0001; F(1, 36) = 5.25, p = 0.02, respectively] and an effect of sex on the expression of C5aR1 in liver 5 d post infection [F(1, 36) = 5.55, p = 0.02] (Figure 8). Here, C5AR2 is linked to bacterial infectious disease.