Project description:To investigate the effect of cholic acid sulfate to MAIT cells, PBMCs were stimulated with 5-OP-RU and CA7S and scRNA sequencing was performed. Inflammatory genes were induced by 5-OP-RU, while wound healing related genes were inducesed by CA7S. This analysis showed that cholic acid sulfate may contributes to maintenance of MAIT cells.
Project description:Mucosal associated invariant T (MAIT) cells, already differentiated and located at mucosal sites, are critical in the body’s first wave of defenses against invading pathogens. Bcl11b KO MAIT cells fail to be maintained both in the thymus and peripheral organs. Furthermore, MAIT cells fail to fully develop in the thymus without Bcl11b, failing to upregulate RORγt, and that phenotype remains in the lungs and livers of these mice. Bcl11b deletion in MAIT cells causes dramatic shifts in the activation and TH17 programs, due to the binding of Bcl11b in many of those genes, which we have seen in the human MAIT cells. MAIT cells rely on PLZF and RORγt for their development and function, while also heavily relying on Bcl11b. These data show the key interplay of Bcl11b with PLZF and RORγt in a T cell leading to its development and necessary function to protect the body against diseases.
Project description:To show the similarity among MAIT-iPSCs, hiPSCs and hESCs and the gradual change of global gene expression of reMAIT cells along with differentiation, this experiment was designed. MAIT cells, MAIT-iPSCs, hiPSCs, hESCs, MAIT cells, and reMAIT cells at the several differerent stages of differentiation were collected. Then, they were applied in this experiment.
Project description:Mucosal associated invariant T (MAIT) cells, already differentiated and located at mucosal sites, are critical in the body’s first wave of defenses against invading pathogens. Bcl11b KO MAIT cells fail to be maintained both in the thymus and peripheral organs. Furthermore, MAIT cells fail to fully develop in the thymus without Bcl11b, failing to upregulate RORγt, and that phenotype remains in the lungs and livers of these mice. Bcl11b deletion in MAIT cells causes dramatic shifts in the activation and TH17 programs, due to the binding of Bcl11b in many of those genes, which we have seen in the human MAIT cells. MAIT cells rely on PLZF and RORγt for their development and function, while also heavily relying on Bcl11b. These data show the key interplay of Bcl11b with PLZF and RORγt in a T cell leading to its development and necessary function to protect the body against diseases.
Project description:Mucosal associated invariant T (MAIT) cells are an abundant population of innate T cells that recognize bacterial ligands and play a key role in host protection against bacterial and viral pathogens. Upon activation, MAIT cells undergo proliferative expansion and increase their production of effector molecules such as cytokines. In this study, we found that mRNA and protein the abundance of the key metabolism regulator and transcription factor MYC was increased in stimulated MAIT cells. Using quantitative mass spectrometry, we identified the activation of two MYC controlled metabolic pathways, amino acid transport and glycolysis, both of which were necessary for MAIT cell proliferation. Finally, we showed that MAIT cells isolated from people with obesity showed decreased MYC mRNA abundance upon activation, which was associated with defective MAIT cell proliferation and functional responses. Collectively, our data uncovers the importance of MYC-regulated metabolism for MAIT cell proliferation and provides additional insight into the molecular basis for the functional defects of MAIT cells in obesity.
Project description:Mucosal-associated invariant T (MAIT) cells are innate-like T cells that recognize microbial metabolites through a semi-invariant T cell receptor (TCR). Major questions remain regarding the extent of human MAIT cell functional and clonal diversity. To address these, we analyzed the single-cell transcriptome and TCR repertoire of blood and liver MAIT cells and developed functional RNA sequencing, a method to integrate function and TCR clonotype at single-cell resolution. MAIT cell clonal diversity was comparable to conventional memory T cells, with private TCR repertoires shared across matched tissues. Baseline functional diversity was low and largely related to tissue site. MAIT cells showed stimulus-specific transcriptional responses in vitro, with cells positioned along gradients of activation. Clonal identity influenced resting and activated transcriptional profiles but intriguingly was not associated with the capacity to produce IL- 17. Overall, MAIT cells show phenotypic and functional diversity according to tissue localization, stimulation environment and clonotype.
Project description:Mucosa-associated invariant T (MAIT) cells are unconventional innate-like T cells that recognize microbial riboflavin metabolites presented by the MHC class I-like protein MR1. Human MAIT cells predominantly express the CD8α co-receptor (CD8+), with a smaller subset lacking both CD4 and CD8 (DN). However, it is unclear if these two MAIT cell sub-populations distinguished by CD8α represent functionally distinct subsets. To address this, we investigated the phenotypic, transcriptional, and functional differences between CD8+ and DN MAIT cells using human samples from peripheral blood, mucosal tissues, and fetal tissues.
Project description:Mucosal-associated invariant T (MAIT) cells are innate sensors of viruses, which can augment early immune responses and contribute to protection from lethal infection. Thus, we reasoned MAIT cells may have an adjuvating role in the immunogenicity of replication-incompetent adenovirus vectors, which are novel vaccine platforms for pandemic pathogens such as Ebola virus and SARS-CoV-2. In both mice and human volunteers, immunization with ChAdOx1 (Chimpanzee Adenovirus Ox1) robustly activated MAIT cells. Activation required transduction of plasmacytoid dendritic cells and monocytes to produce IFN- and IL-18, respectively. IFN--induced monocyte-derived TNF was identified as a novel intermediate in this activation pathway, and activation required combinatorial signaling of all three cytokines both in vitro and in vivo. Strikingly, vaccine-induced activation of MAIT cells positively correlated with vaccine-induced T cell responses in human volunteers. Supporting a causal relationship, MAIT cell-deficient mice displayed impaired CD8+ T cell responses to multiple vaccine-encoded antigens. These findings define a novel role for MAIT cells in the immunogenicity of adenovirus vector vaccines, with potential implications for vaccine design.