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Hackstein, C.-P.

Publications and source records attributed to Hackstein, C.-P..

3 recordsLinked to original sources

MAIT cells derived ligands signal via VEGFR2 to promote tissue repair and liver regeneration

MAIT are a highly versatile population of innate-like T cells that have been implicated in promoting tissue repair-associated process in a variety of tissue and diseases settings in the last years. While certain specific effector molecules responsible for MAIT-cell mediated have been identified, the mechanisms by which MAIT cells exert repair functions remain incompletely understood. Here, we show that hepatic MAIT cells express VEGFA, VEGFB and vimentin, an alternative ligand for the VEGFA-receptor VEGFR2 in both, regenerating and heathy tissue. Expression and secretion of these factors were induced in vitro by combined T cell receptor and cytokine stimulation. Supernatants of activated MAIT cells were able to promote proliferation of different epithelial and endothelial cells, including a liver sinusoidal endothelial-derived cell line in an VEGFR2-dependent manner. Together, our findings expand our understanding of MAIT cell function, especially in the liver and open new opens avenues for exploring MAIT therapeutic potential in modulating tissue repair.

immunology↗

Primed to resolve: A single cell atlas of the shoulder capsule reveals a cellular basis for resolving inflammatory fibrosis

Fibrotic conditions are a significant global disease burden. While some therapies delay disease progression, none reverse fibrosis. To gain insights into how fibrosis might resolve, we developed a comparative single cell atlas of frozen shoulder capsule tissue; a chronic inflammatory fibrotic human disease that resolves spontaneously. We identified both a population of pro-inflammatory MERTKlowCD48+ macrophages (M{varphi}) and a population of MERTK+LYVE1+MRC1+M{varphi} enriched for negative regulators of inflammation. Micro-cultures of patient-derived cells identified cell-matrix interactions between MERTK+M{varphi} and DKK3+ and POSTN+ fibroblasts, suggesting that matrix remodelling plays a role in the resolution of frozen shoulder. Cross-tissue analysis revealed a shared gene expression cassette between MERTK+M{varphi} in the shoulder capsule and a similar cell population enriched in synovial tissues from rheumatoid arthritis patients in disease remi ssion, supporting the concept that MERTK+M{varphi} provide a cellular basis for the resolution of inflammation and fibrosis. Single-cell transcriptomic profiling and spatial analysis of human foetal shoulder tissues identified MERTK+LYVE1+MRC1+M{varphi} and DKK3+ and POSTN+ fibroblast populations analogous to those identified in adult shoulder capsule, suggesting that the template to resolve fibrosis is established during development. Therapeutic enhancement of crosstalk between MerTK+M{varphi} and pro-resolving DKK3+ and POSTN+ fibroblasts could accelerate resolution of frozen shoulder and resolve persistent inflammatory fibrotic disease in other tissues.

cell biology↗

A conserved population of MHC II-restricted, innate-like, commensal-reactive T cells in the gut of humans and mice

Interactions with commensal microbes shape host immunity on multiple levels and are recognized to play a pivotal role in human health and disease. In this study, we show that MHC-II restricted, commensal-reactive T cells in the colon of both humans and mice acquire transcriptional and functional characteristics typically associated with innate-like T cells, including the expression of the key transcription factor PLZF and the ability to respond to cytokines including IL-12, IL-18 and IL-23 in a TCR-independent manner. These MHC-II restricted, innate-like, commensal-reactive T cells (TMIC) are endowed with a polyfunctional effector potential spanning classic Th1- and Th17-cytokines, cytotoxic molecules as well as regulators of epithelial homeostasis and represent an abundant and conserved cell population in the human and murine colon. T cells with the TMIC phenotype were increased in ulcerative colitis patients and their presence aggravated pathology in DSS-treated mice, pointing towards a pathogenic role in colitis. Our findings add TMIC cells to the expanding spectrum of innate-like immune cells positioned at the frontline of intestinal immune surveillance, capable of acting as sentinels of microbes and the local cytokine milieu.

immunology↗