The genes with the characteristic pattern for M2-related response comprised IL-4R, mannose receptor, TfR1, CD163, MMP12 and TIMP1 and in all of them, significantly lower expression was observed after PAM infection with the ΔSPI-1 mutant when compared to the expression in PAMs infected with wild-type Salmonella Typhimurium or the ΔSPI-2 mutant (Figure 3). Here, MMP12 is linked to infection.