In the extension of these studies (Fig. 4a,b), we found that by day 14 of Cr infection, 90% of LY6G+ DCC and FABP2+ PCC cells from the mid–distal colon upregulate MHCII, compared with 20% of FABP2+ PCCs and distal illeal enterocytes. The gene discussed is FABP2; the disease is infection.