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Hinks, T. S. C.

Publications and source records attributed to Hinks, T. S. C..

3 recordsLinked to original sources

MAIT cells protect against sterile lung injury

Mucosal-associated invariant T (MAIT) cells, the most abundant unconventional T cells in the lung, have been recently linked to tissue protection and repair. Their role, especially in sterile lung injury, is unknown. Using single cell RNA sequencing (scRNA-seq), spectral analysis and adoptive transfer in a bleomycin-induced sterile lung injury, we found that bleomycin activates murine pulmonary MAIT cells and induces an accompanying tissue repair programme, associated with a protective role against bleomycin-induced lung injury. MAIT cells drive the accumulation of type 1 conventional dendritic cells (cDC1), limiting tissue damage in a DNGR-1 dependent manner. Human scRNA-seq data revealed that MAIT cells were activated, with increased cDC populations in idiopathic pulmonary fibrosis patients. Thus, MAIT cells enhance defence against sterile lung injury by fostering cDC1-driven anti-fibrotic pathways.

immunology↗

Activation and in vivo evolution of the MAIT cell transcriptome in mice and humans reveals diverse functionality

Mucosal-associated invariant T (MAIT) cells are MR1-restricted innate-like T cells conserved across mammalian species, including mice and humans. By sequencing RNA from sorted MR1-5-OP-RU tetramer+ cells derived from either human blood or murine lungs, we define the basic transcriptome of an activated MAIT cell in both species and demonstrate how this profile changes during resolution and reinfection phases of infection. We observe strong similarities between MAIT cells in humans and mice. Compared with previously published T cell transcriptomes, MAIT cells displayed most similarity to iNKT cells when activated, but to {gamma}{delta} T cells, after resolution of infection. In both species activation leads to strong expression of pro-inflammatory cytokines and chemokines, and also a strong tissue repair signature, recently described in murine commensal-specific H2-M3-restricted T cells. These data define the requirements for, and consequences of, MAIT cell activation, revealing a tissue repair phenotype expressed upon MAIT cell activation in both species.

immunology↗

Legionella protection and vaccination mediated by Mucosal Associated Invariant T (MAIT) cells

Mucosal associated invariant T (MAIT) cells recognize conserved microbial metabolites from riboflavin synthesis. Striking evolutionary conservation and pulmonary abundance implicate them in antibacterial host defense, yet their roles in protection against clinically significant pathogens are unknown. Murine Legionella infection induced MR1-dependent MAIT cell activation and rapid pulmonary accumulation of MAIT cells associated with immune protection detectable in fully immunocompetent host animals. MAIT cell protection was more evident in mice lacking CD4+ cells, whilst profoundly immunodeficient RAG2-/-{gamma}C-/- mice were substantially rescued from uniformly lethal Legionella infection by adoptively-transferred MAIT cells. This protection was dependent on MR1, IFN-{gamma} and GM-CSF, but not IL-17, TNF- or perforin. Protection was enhanced and observed earlier post-infection in mice that were Ag-primed to boost MAIT cells before infection. Our findings define a significant role for MAIT cells in protection against a major human pathogen and indicate a potential role for vaccination to enhance MAIT cell immunity.

immunology↗