Project description:To investigate the effect of Mthfd2 KO in alloreactive CD4+ T cells. We performed in vitro mixed lymphocyte to induce alloreactive T cells. CD4+ T cells were respectively purified from the spleens of 8-week-old TEaWT and TEaMthfd2 KO mice by magnetic-activated cell sorting (MACS) positive selection. APCs were sorted from the spleens of 8-week-old F1 (BALB/c x C57BL/6) mice. CD4+ T cells were cocultured with APCs three days and then performed RNA-sequencing.
Project description:This study aims to characterize the H3K4me3 modification in wild type and Mthfd2 KO activated T cells, and find the potential mechanism of the Mthfd2 KO in alloreactive T cells.
Project description:Adoptive natural regulatory T cell (nTreg) therapy has improved the outcome for patients suffering from graft-versus-host disease (GVHD) following allogeneic hematopoietic cell transplantation (allo-HCT). However, fear of broad immune suppression and subsequent dampening of beneficial graft-versus-leukemic (GVL) responses remains a challenge. To address this concern, we generated alloreactive induced Tregs (iTregs) from resting CD4 or CD8 T cells and tested their ability to suppress GVH and maintain GVL responses. We utilized major mismatched and haploidentical murine models of HCT with host-derived lymphoma or leukemia cell lines to evaluate GVH and GVL responses simultaneously. Alloreactive CD4 iTregs were effective in preventing GVHD, but abrogated the GVL effect against aggressive leukemia. Alloreactive CD8 iTregs moderately attenuated GVHD while sparing the GVL effect. Hence, we reasoned that using a combination of CD4 and CD8 iTregs could achieve the optimal goal of allo-HCT. Indeed, the combinational therapy was superior to CD4 or CD8 iTreg singular therapy in GVHD control; importantly, the combinational therapy maintained GVL responses. Cellular analysis uncovered potent suppression of both CD4 and CD8 effector T cells by the combinational therapy that resulted in effective prevention of GVHD, which could not be achieved by either singular therapy. Gene expression profiles revealed alloreactive CD8 iTregs possess elevated expression of multiple cytolytic molecules compared to CD4 iTregs, which likely contributes to GVL preservation. Our study uncovers unique differences between alloreactive CD4 and CD8 iTregs that can be harnessed to create an optimal iTreg therapy for GVHD prevention with maintained GVL responses.
Project description:Alloreactive CD4+ T cells play a central role in allograft rejection, We used single cell RNA sequencing (scRNA-seq) to analyze the cell states of alloreactive CD4+ T cells in periphery and allografts to better understand how alloreactive CD4+ T cells drive allograft rejection.
Project description:To identify how Id3 transcriptionaly regulate alloreactive CD4 T cells and whether this leads to the generation of distinct alloreactive donor T cell populations.
Project description:Subcellular compartmentalization of metabolic enzymes may elicit specific cellular functions by establishing a unique metabolic environment. Indeed, the nuclear translocation of certain metabolic enzymes is required for epigenetic regulation and gene expression control. Here, we reveal that, in cancer cells, the mitochondrial enzyme methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) localizes in the nucleus during the G2-M phase of the cell cycle to secure mitosis progression. Nuclear MTHFD2 interacts with proteins involved in mitosis regulation and centromere stability, including the methyltransferases KMT5A and DNMT3B. Loss of MTHFD2 induces centromere overexpression and severe methylation defects, and impedes correct mitosis completion. As a consequence, MTHFD2 deficient cells accumulate chromosomal aberrations arising from chromosome congression and segregation defects. Blocking the catalytic nuclear function of MTHFD2 recapitulates the phenotype observed in MTHFD2 deficient cells, attributing to nuclear MTHFD2 an enzymatic active role in controlling mitosis. Our discovery uncovers a nuclear moonlighting role for the cancer target MTHFD2, and emphasizes that cancer metabolism rewiring may encompass the relocation of metabolic enzymes to alternative subcellular compartments.
Project description:The extent to which tissue-resident memory T (TRM) cells in transplanted organs possess alloreactivity is uncertain. This study investigates the alloreactive potential of TRM cells in kidney explants from four patients who experienced severe acute rejection leading to graft loss. Alloreactive T-cell receptors (TCRs) clones were identified in pre-transplant blood samples through mixed lymphocyte reactions, followed by single-cell RNA and TCR sequencing of the proliferated recipient T cells. Subsequently, these TCR clones were traced in the TRM cells of kidney explants, which were also subjected to single-cell RNA and TCR sequencing. The proportion of TRM cells expressing an alloreactive TCR in the four kidney explants varied from 0% to 9%. Notably, these alloreactive TCRs were predominantly found among CD4+ and CD8+ TRM cells with an effector phenotype. Intriguingly, alloreactive clones were present not only in recipient-derived TRM cells but also in donor-derived TRM cells, constituting up to 4% of the donor population, suggesting the presence of self-reactive TRM cells. Overall, our study demonstrates that T cells with alloreactive potential present in the peripheral blood prior to transplantation can infiltrate the kidney transplant and adopt a TRM phenotype.
Project description:Subcellular compartmentalization of metabolic enzymes may elicit specific cellular functions by establishing a unique metabolic environment. Indeed, the nuclear translocation of certain metabolic enzymes is required for epigenetic regulation and gene expression control. Here, we reveal that, in cancer cells, the mitochondrial enzyme methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) localizes in the nucleus during the G2-M phase of the cell cycle to secure mitosis progression. Nuclear MTHFD2 interacts with proteins involved in mitosis regulation and centromere stability, including the methyltransferases KMT5A and DNMT3B. Loss of MTHFD2 induces centromere overexpression and severe methylation defects, and impedes correct mitosis completion. As a consequence, MTHFD2 deficient cells accumulate chromosomal aberrations arising from chromosome congression and segregation defects. Blocking the catalytic nuclear function of MTHFD2 recapitulates the phenotype observed in MTHFD2 deficient cells, attributing to nuclear MTHFD2 an enzymatic active role in controlling mitosis. Our discovery uncovers a nuclear moonlighting role for the cancer target MTHFD2, and emphasizes that cancer metabolism rewiring may encompass the relocation of metabolic enzymes to alternative subcellular compartments.
Project description:Lung cancer is leading cause of cancer-related death in the world, because of high recurrence rate and acquired resistance to targeting drugs such as gefitinib. Here we uncover a critical MTHFD2 enzyme-mediated purine synthesis pathway in mitochondria in poor prognostic lung cancer. Expression of MTHFD2 was induced by epidermal growth factor (EGF) stimulation. It was overexpressed in gefitinib-resistant cancer cells and high-grade tumor tissues. Knockdown of MTHFD2 significantly decreased not only in vitro and in vivo cell growth but also tumor sphere formation and tumor initiating activity, properties of cancer stem-like cells. Integrated analysis of metabolome and transcriptome of MTHFD2 knocked-down cells revealed significant accumulation of the nucleotide intermediates before MTHFD2-mediated one carbon transfer and marked deficiency of purine nucleotides required for cell growth. Thus we provide evidence that MTHFD2 pathway is critical for growth of both cancer cells and cancer stem-like cells as an Achilles heel to eradicate tumors in poor prognostic lung cancer.