Bernardo, DavidMarin, Alicia CFernández-Tomé, SamuelMontalban-Arqués, AnaCarrasco, ATristan, EOrtega Moreno, LorenaMora-Gutierrez, IreneDiaz-Guerra, ACaminero-Fernández, RMiranda, PCasals, FCaldas, MJiménez, MCasabona, Sergiode la Morena, FEsteve, MSantander, CecilioChaparro, MaríaGisbert, Javier P.2023-11-302023-11-302018Bernardo, D., Marin, A.C., Fernández-Tomé, S. et al. Human intestinal pro-inflammatory CD11chighCCR2+CX3CR1+ macrophages, but not their tolerogenic CD11c−CCR2−CX3CR1− counterparts, are expanded in inflammatory bowel disease. Mucosal Immunol 11, 1114–1126 (2018). https://doi.org/10.1038/s41385-018-0030-71114–1126https://hdl.handle.net/10115/26777Although macrophages (Mϕ) maintain intestinal immune homoeostasis, there is not much available information about their subset composition, phenotype and function in the human setting. Human intestinal Mϕ (CD45+HLA-DR+CD14+CD64+) can be divided into subsets based on the expression of CD11c, CCR2 and CX3CR1. Monocyte-like cells can be identified as CD11chighCCR2+CX3CR1+ cells, a phenotype also shared by circulating CD14+ monocytes. On the contrary, their Mϕ-like tissue-resident counterparts display a CD11c−CCR2−CX3CR1− phenotype. CD11chigh monocyte-like cells produced IL-1β, both in resting conditions and after LPS stimulation, while CD11c− Mϕ-like cells produced IL-10. CD11chigh pro-inflammatory monocyte-like cells, but not the others, were increased in the inflamed colon from patients with inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis. Tolerogenic IL-10-producing CD11c− Mϕ-like cells were generated from monocytes following mucosal conditioning. Finally, the colonic mucosa recruited circulating CD14+ monocytes in a CCR2-dependent manner, being such capacity expanded in IBD. Mϕ subsets represent, therefore, transition stages from newly arrived pro-inflammatory monocyte-like cells (CD11chighCCR2+CX3CR1+) into tolerogenic tissue-resident (CD11c−CCR2−CX3CR1−) Mϕ-like cells as reflected by the mucosal capacity to recruit circulating monocytes and induce CD11c− Mϕ. The process is nevertheless dysregulated in IBD, where there is an increased migration and accumulation of pro-inflammatory CD11chigh monocyte-like cells.Attribution 4.0 Internationalhttps://creativecommons.org/licenses/by/4.0/info:eu-repo/semantics/article10.1038/s41385-018-0030-7info:eu-repo/semantics/openAccess