MPTX1 and infection: Here, we have shown that genes encoding the activator of NK cells (KIR2DS1, KLRJ1) were markedly up-regulated in the intestine tissue of CE infection sheep at 4-hour post infection, suggesting that NK cells might be strongly activated, and thus pose a high cytotoxic potential very early during infection, which is supported by the high expression of MPTX gene encoding mucosal pentraxin.