While no significant increase of infiltrating monocytes (Ly6c+Ly6g−MHCIIlow-mid+CCR2+) or dendritic cells (Ly6g−Ly6c+MHCIIhigh+CD11c+) was noted by numbers (Supplementary Fig. 4f) or frequencies (not shown), we noted increased numbers of resident macrophages (Ly6g−Ly6c−CD11b+F4/80+MHCII+CX3CR1+) in SPF + P mice during DSS colitis (Supplementary Fig. 4f). Here, CX3CR1 is linked to colitis.