In the absence of Pb-infection, no significant difference was observed in serum AST (MRP14-injected, 119 ± 27 IU/L; PBS-injected, 134 ± 28 IU/L) and ALT (rMRP14-injected, 25 ± 6 IU/L; PBS-injected, 29 ± 10 IU/L) between the rMRP14-injected mice and PBS-injected mice. This evidence concerns the gene S100A9 and infection.