TY - JOUR

T1 - Maintenance of Barrier Tissue Integrity by Unconventional Lymphocytes

AU - Cox, Joshua R.

AU - Cruickshank, Sheena M.

AU - Saunders, Amy E.

N1 - Funding Information: This work was supported by a Wellcome Trust Sir Henry Dale Fellowship to AS (109375/Z/15/Z) and a Medical Research Council (MRC) DTP studentship to JC. Publisher Copyright: © Copyright © 2021 Cox, Cruickshank and Saunders.

PY - 2021/4/14

Y1 - 2021/4/14

N2 - Mucosal surfaces, as a first barrier with the environment are especially susceptible to damage from both pathogens and physical trauma. Thus, these sites require tightly regulated repair programs to maintain barrier function in the face of such insults. Barrier sites are also enriched for unconventional lymphocytes, which lack rearranged antigen receptors or express only a limited range of such receptors, such as ILCs (Innate Lymphoid Cells), γδ T Cells and MAIT (Mucosal-Associated Invariant T Cells). Recent studies have uncovered critical roles for unconventional lymphocytes in regulating mucosal barrier function, and, in particular, have highlighted their important involvement in barrier repair. The production of growth factors such as amphiregulin by ILC2, and fibroblast growth factors by γδ T cells have been shown to promote tissue repair at multiple barrier sites. Additionally, MAIT cells have been shown to exhibit pro-repair phenotypes and demonstrate microbiota-dependent promotion of murine skin healing. In this review we will discuss how immune responses at mucosal sites are controlled by unconventional lymphocytes and the ways in which these cells promote tissue repair to maintain barrier integrity in the skin, gut and lungs.

AB - Mucosal surfaces, as a first barrier with the environment are especially susceptible to damage from both pathogens and physical trauma. Thus, these sites require tightly regulated repair programs to maintain barrier function in the face of such insults. Barrier sites are also enriched for unconventional lymphocytes, which lack rearranged antigen receptors or express only a limited range of such receptors, such as ILCs (Innate Lymphoid Cells), γδ T Cells and MAIT (Mucosal-Associated Invariant T Cells). Recent studies have uncovered critical roles for unconventional lymphocytes in regulating mucosal barrier function, and, in particular, have highlighted their important involvement in barrier repair. The production of growth factors such as amphiregulin by ILC2, and fibroblast growth factors by γδ T cells have been shown to promote tissue repair at multiple barrier sites. Additionally, MAIT cells have been shown to exhibit pro-repair phenotypes and demonstrate microbiota-dependent promotion of murine skin healing. In this review we will discuss how immune responses at mucosal sites are controlled by unconventional lymphocytes and the ways in which these cells promote tissue repair to maintain barrier integrity in the skin, gut and lungs.

KW - barrier

KW - innate lymphoid cell

KW - mucosal-associated invariant T cell

KW - repair

KW - review

KW - γδ T cell

U2 - 10.3389/fimmu.2021.670471

DO - 10.3389/fimmu.2021.670471

M3 - Review article

C2 - 33936115

AN - SCOPUS:85104995450

VL - 12

JO - Frontiers in Immunology

JF - Frontiers in Immunology

SN - 1664-3224

M1 - 670471

ER -