ABSTRACT: CD8 tissue-resident memory T (TRM) cells provide front-line protection at barrier tissues; however, mechanisms regulating TRM cell development are not completely understood. Priming dictates the migration of effector T cells to the tissue, while factors in the tissue induce in situ TRM cell differentiation. Whether priming also regulates in situ TRM cell differentiation uncoupled from migration is unclear. Here, we demonstrate that T cell priming in the mesenteric lymph nodes (MLN) regulates CD103+ TRM cell differentiation in the intestine. In contrast, T cells primed in the spleen were impaired in the ability to differentiate into CD103+ TRM cells after entry into the intestine. MLN priming initiated a CD103+ TRM cell gene signature and licensed rapid CD103+ TRM cell differentiation in response to factors in the intestine. Licensing was regulated by retinoic acid signaling and primarily driven by factors other than CCR9 expression and CCR9-mediated gut homing. Thus, the MLN is specialized to promote intestinal CD103+ CD8 TRM cell development by licensing in situ differentiation.
Project description:Current cancer immunotherapies promote recovery of CD103+ tissue-resident memory T cells (Trm) population of the tumor-infiltrating T lymphocytes (TILs). However, not all treated patients exhibit improved anti-tumor immunity and survival, likely due to the immunophenotypical diversity among the CD103+ Trm TILs. Utilising multifaceted proteomics approaches and patients’ clinical analyses, we discovered an unusual subset of CD8+ Trm TILs expressing non-canonical integrin β3 early during T cells activation. The integrin β3 surprisingly heterodimerises with CD103 on T cells, leading to unconventional granulysin-mediated cytotoxicity, elevated alternative bioenergy usage and efficient T cell migration, with minimal overall exhaustion. Importantly, early-stage non-small cell lung carcinoma (NSCLC) patients with enriched presence of integrin β3+CD103+ Trm TILs exhibited better clinical prognosis, with improved T cell immunophenotype, hence confirming the beneficial role of this unusual subset of Trm TILs. These unconventional anti-tumor T cell features provide new avenues and future opportunities for designing better translational immunotherapy strategies.
Project description:Dendritic cells (DCs) in tissues and lymphoid organs comprise distinct functional subsets that differentiate in situ from circulating progenitors. Tissue-specific signals that regulate DC subset differentiation are poorly understood. We report that DC-specific deletion of the Notch2 receptor caused a reduction of DC populations in the spleen. Within the splenic CD11b+ DCs, Notch signaling blockade ablated a distinct population marked by high expression of adhesion molecule Esam. The Notch-dependent Esamhi DC subset also required lymphotoxin beta receptor signaling, proliferated in situ and facilitated efficient CD4+ T cell priming. The Notch-independent Esamlo DCs expressed monocyte-related genes and showed superior cytokine responses. In addition, Notch2 deletion led to the loss of CD11b+ CD103+ DCs in the intestinal lamina propria and to the corresponding decrease of IL-17-producing CD4+ T cells in the intestine. Thus,Notch2 is a common differentiation signal for T cell-priming CD11b+ DC subsets in the spleen and intestine.
Project description:Tissue-resident memory T cells (TRM) are non-recirculating cells that exist throughout the body. While TRM in various organs rely on common transcriptional networks to establish tissue residency, location-specific factors adapt these cells to their tissue of lodgment. Here, we chart TRM heterogeneity between organs and find that the different environments in which these cells differentiate dictate TRM function, durability and malleability. We find that unequal responsiveness to TGF-β is a major driver of this diversity. Strikingly, dampened TGF-b signaling engendered CD103- TRM with increased proliferative potential, enhanced function, and reduced longevity compared to their TGF-β-responsive CD103+ TRM counterparts. Further, while CD103- TRM readily modified their phenotype upon relocation, CD103+ TRM were comparatively resistant to trans-differentiation. Thus, despite common requirements for TRM development, adaptation of these cells to their tissue of residence confers discrete functional properties such that TRM exist along a spectrum of differentiation potential that is governed by their local microenvironment.
Project description:Tissue-resident memory T cells (TRM) are non-recirculating cells that exist throughout the body. While TRM in various organs rely on common transcriptional networks to establish tissue residency, location-specific factors adapt these cells to their tissue of lodgment. Here, we chart TRM heterogeneity between organs and find that the different environments in which these cells differentiate dictate TRM function, durability and malleability. We find that unequal responsiveness to TGF-β is a major driver of this diversity. Strikingly, dampened TGF-b signaling engendered CD103- TRM with increased proliferative potential, enhanced function, and reduced longevity compared to their TGF-β-responsive CD103+ TRM counterparts. Further, while CD103- TRM readily modified their phenotype upon relocation, CD103+ TRM were comparatively resistant to trans-differentiation. Thus, despite common requirements for TRM development, adaptation of these cells to their tissue of residence confers discrete functional properties such that TRM exist along a spectrum of differentiation potential that is governed by their local microenvironment.
Project description:Tissue-resident memory T cells (TRM) are non-recirculating cells that exist throughout the body. While TRM in various organs rely on common transcriptional networks to establish tissue residency, location-specific factors adapt these cells to their tissue of lodgment. Here, we chart TRM heterogeneity between organs and find that the different environments in which these cells differentiate dictate TRM function, durability and malleability. We find that unequal responsiveness to TGF-β is a major driver of this diversity. Strikingly, dampened TGF-b signaling engendered CD103- TRM with increased proliferative potential, enhanced function, and reduced longevity compared to their TGF-β-responsive CD103+ TRM counterparts. Further, while CD103- TRM readily modified their phenotype upon relocation, CD103+ TRM were comparatively resistant to trans-differentiation. Thus, despite common requirements for TRM development, adaptation of these cells to their tissue of residence confers discrete functional properties such that TRM exist along a spectrum of differentiation potential that is governed by their local microenvironment.
Project description:Tissue resident memory (Trm) represent a newly described memory T cell population. We have previously characterized a population of Trm that persists within the brain following acute virus infection. Although capable of providing marked protection against a subsequent local challenge, brain Trm do not undergo recall expansion following dissociation from the tissue. Furthermore, these Trm do not depend on the same survival factors as the circulating memory T cell pool as assessed either in vivo or in vitro. To gain greater insight into this population of cells we compared the gene-expression profiles of Trm isolated from the brain to circulating memory T cells isolated from the spleen following an acute virus infection. Trm displayed altered expression of genes involved in chemotaxis, expressed a distinct set of transcription factors and overexpressed several inhibitory receptors. Cumulatively, these data indicates that Trm are a distinct memory T cell population disconnected from the circulating memory T cell pool and displaying a unique molecular signature which likely results in optimal survival and function within their local environment. 13 samples were analyzed: 5 replicates of memory OT-I CD8+.CD103- T cells isolated from the spleen of mice on day 20 p.i. with VSV-OVA. 5 replicates of memory OT-I CD8+CD103+ T cells isolated from the brain of mice on day 20 p.i. with VSV-OVA; and 3 replicates of memory OT-I.CD8+ CD103- T cells isolated from the brain of mice on day 20 p.i. with VSV-OVA
Project description:Cancer remains one of the leading causes of mortality worldwide, with increasing public health interest towards immunological-based approach in disease treatments. Enrichment of certain cell population, namely the CD103+ tissue-resident memory T (Trm) cells has been associated with better clinical prognosis in cancer as well as other inflammatory-diseased patients. However, the identity of specific biomarkers and mechanisms that can contribute towards protective immunity remains unclear. Here, we identified an unexpected CD61 expression on human cancer-specific CD103+ T cells, which formed unconventional transient pairing with CD103 on the synaptic microclusters following antigen recognition, through proteomics, synaptic microscopy and co-immunoprecipitation analyses. Further CD61 co-localisation with T cell receptor (TCR) at the synaptic centre demonstrated modulation of TCR signalling through specific adaptor proteins, which improves anti-tumor cytotoxicity and promote better physiological control of tumor growths in immunocompromised mouse model. Clinically, presence of CD61+ Trm cells are associated with improved patients’ outcome, mediated through enhanced effector functions and phenotypes whilst mitigating hallmarks of cellular exhaustion. This study identified an unconventional and transient CD61 expression and pairing with CD103 on human immune cells, which acts as an important pathway to mediate effective immunity, implicating a novel target for immune-based cellular therapies.
Project description:CD49a marks highly cytotoxic epidermal tissue-resident memory (TRM)-cells, but their molecular circuitry and relationships to circulating populations are poorly defined. We demonstrate enrichment of RUNX family transcription factor binding motifs in human epidermal CD8+CD103+CD49a+ TRM-cells, paralleled by high RUNX2 and RUNX3 protein expression. Clonal overlap between epidermal CD8+CD103+CD49a+ TRM-cells and circulating memory CD8+CD45RA–CD62L+ T-cells identified a reservoir of circulating cells with potential to seed cytotoxic TRM-cells in new sites. Upon IL-15 and TGF-β stimulation, subsets of circulating CD8+CD45RA–CD62L+ T-cells acquired CD49a expression and cytotoxic transcriptional profiles in a RUNX2 and RUNX3 dependent manner. In contrast, knock-out of RUNX3, but not RUNX2, prevented CD103 expression. In melanoma, high RUNX2, but not RUNX3, transcription correlated with a cytotoxic CD8+CD103+CD49a+ TRM cell signature and overall patient survival. Together, our results indicate that combined RUNX2 and RUNX3 activity promotes the differentiation of cytotoxic CD8+CD103+CD49a+ TRM-cells, providing immunosurveillance of infected and malignant cells.
Project description:CD49a marks highly cytotoxic epidermal tissue-resident memory (TRM)-cells, but their molecular circuitry and relationships to circulating populations are poorly defined. We demonstrate enrichment of RUNX family transcription factor binding motifs in human epidermal CD8+CD103+CD49a+ TRM-cells, paralleled by high RUNX2 and RUNX3 protein expression. Clonal overlap between epidermal CD8+CD103+CD49a+ TRM-cells and circulating memory CD8+CD45RA–CD62L+ T-cells identified a reservoir of circulating cells with potential to seed cytotoxic TRM-cells in new sites. Upon IL-15 and TGF-β stimulation, subsets of circulating CD8+CD45RA–CD62L+ T-cells acquired CD49a expression and cytotoxic transcriptional profiles in a RUNX2 and RUNX3 dependent manner. In contrast, knock-out of RUNX3, but not RUNX2, prevented CD103 expression. In melanoma, high RUNX2, but not RUNX3, transcription correlated with a cytotoxic CD8+CD103+CD49a+ TRM cell signature and overall patient survival. Together, our results indicate that combined RUNX2 and RUNX3 activity promotes the differentiation of cytotoxic CD8+CD103+CD49a+ TRM-cells, providing immunosurveillance of infected and malignant cells.