To assess the early leukocyte recruitment to the gut we quantified two key sentinel cells, the macrophage (MHC II+, F4/80+ CD11b+) and the DC (MHCII+, CD11c+, CD103+ Dec205+), in the large intestinal lamina propria by flow cytometry (Fig. 1I, on Days 0, 1, 2 and 3 post infection) and immunohistochemistry (Fig. 1J,K, on Day 0 and Day 1 post infection). This evidence concerns the gene ITGAM and infection.