PTGS2 and infection: Many cytokines can be regulated by the TNF signaling pathway, and the infection caused up-regulation of genes encoding leukocyte recruitment factors (Ccl2, Ccl20, Cxcl1, Cxcl2, Cxcl3 and Cxcl10), leukocyte activation factors (Csf1 and Csf2), surface receptors (Fas), inflammatory cytokines (Il1b, Il6, Il15, Lif and Tnf), intracellular signaling molecules (Bcl3, Nfkbia, Socs3, Tnfaip3 and Traf1), transcription factors (Fos and JunB), an extracellular matrix remodeling factor (Mmp9), PRRS (Nod2), and cell adhesion factors (Icam1, Sele and Vcam1) and synthesis of inflammatory mediators (Ptgs2).