Type 3 innate lymphoid cells are associated with a successful intestinal transplant.

Although innate lymphoid cells (ILCs) play fundamental roles in mucosal barrier functionality and tissue homeostasis, ILC-related mechanisms underlying intestinal barrier function, homeostatic regulation, and graft rejection in intestinal transplantation (ITx) patients have yet to be thoroughly defined. We found protective type 3 NKp44 ILCs (ILC3s) to be significantly diminished in newly transplanted allografts, compared to allografts at 6 months, whereas proinflammatory type 1 NKp44 ILCs (ILC1s) were higher. Moreover, serial immunomonitoring revealed that in healthy allografts, protective ILC3s repopulate by 2-4 weeks postoperatively, but in rejecting allografts they remain diminished.

An integrated understanding of the immunology of allograft inflammation.

Purpose Of Review: The purpose of this review is to summarize recent advances in our understanding of the complex immunology of intestinal transplantation and allograft rejection.

Recent Findings: Recent findings highlight the importance of the intestinal microbiome for intestinal homeostasis and the role of newly discovered innate lymphoid cells in intestinal transplantation. In addition, the role of host antimicrobial Th17 responses in the pathogenesis of inflammatory bowel diseases and intestinal allograft rejection has been further elucidated.