Project description:To characterize the FcRL3+ T cell subset in memory helper CD4+, CD8+, and CD4+ regulatory lymphocytes, we performed RNA-sequencing analysis using T cells, separated by the expression of FcRL3, from the peripheral blood of 5 healthy donors, stimulated for 3h with PMA and ionomycin to induce cytokine expression.
Project description:CD4+ T lymphocytes are key to immunological memory, but little is known about the lifestyle of memory CD4+ T lymphocytes. We showed that in the memory phase of specific immune responses to antigens, most of the memory CD4+ T lymphocytes relocated into the bone marrow (BM) within 3-8 weeks after their generation, a process involving integrin a2. Antigen-specific memory CD4+ T lymphocytes expressed Ly-6C to a high degree, unlike most splenic CD44hiCD62L- CD4+ T lymphocytes. In adult mice, more than 80% of Ly-6Chi CD44hiCD62L- memory CD4+ T lymphocytes were in the BM. In the BM, they are located next to IL-7-expressing VCAM-1+ stroma cells, and were in a resting state. Upon challenge with antigen, they rapidly expressed cytokines and CD154 and induced the production of high-affinity antibodies, indicating their functional activity in vivo and marking them as professional memory T helper cells
Project description:To understand tissue resident features of memory CD4+ and CD8+ T lymphocytes of the bone marrow and/or spleen according to expressing or not the tissue retention marker CD69, we performed whole transcriptome profiling of ex vivo antigen-specific CD69+ and CD69- memory CD4+ T cells isolated from bone marrow and spleen, and ex vivo CD69+ and CD69- memory CD8+ T cells isolated from bone marrow.
Project description:Using scRNA-seq we investigate the impact of the absence of MYC on physio-pathological development of PTEN-proficient or PTEN-deficient T lymphocytes. We demonstrate that MYC-deficient effector/memory T cells is drastically reduced. MYC is then essential for effector/memory differentiation
Project description:Understanding the mechanisms that modulate T helper lymphocyte functions is crucial to decipher normal and pathogenic immune responses in humans. To identify molecular determinants influencing the pathogenicity of T cells, we separated ex vivo-isolated primary human memory T lymphocytes based on their ability to produce high levels of inflammatory cytokines. We found that the inflammatory, cytokine-producing phenotype of memory T lymphocytes was defined by a specific core gene signature and was mechanistically regulated by the constitutive activation of the NF-kB pathway and by the expression of the transcriptional repressor BHLHE40. BHLHE40 attenuated the expression of anti-inflammatory factors, including miR-146a, a negative regulator of NF-kB activation, and ZC3H12D, an RNase of the Regnase-1 family able to degrade inflammatory transcripts. Our data reveal a molecular network regulating the pro-inflammatory phenotype of human memory T lymphocytes, with the potential to contribute to disease.
Project description:Gene expression data of primary human naive and memory CD4+T lymphocytes purified from peripheral blood are generated to be analyzed in different ways such as for traditional searching of differentially expressed genes between the two cell subsets or in combination to in-silico data of microRNAs target prediction for microRNAs known to be characteristically expressed in the two cell subsets. Two cell subsets (cell types) FACS purified from peripheral blood of six samples/healthy donors (samples #3,5,6,7,026,065). Naive CD4+ T cells were extracted from all 6 samples and 6 biological replicas were obtained (3N, 5N, 6N, 7N, 026N, 065N), while memory CD4+T cells were extracted from 4 samples and 4 biological replicas were obtained (3m, 5m, 6m, 7m). Both naive and memory replicas from samples 3, 5, 6 and 7 were hybridized onto two beadsarrays each while those from samples 026 and 065 were hybridized on 1 beadsarray each (for a total of 18 beadsarrays used). For analysis purposes naive cells samples 3N, 5N, 6N and 7N can be considered paired with memory samples 3m, 5m, 6m and 7m respectively, since they are obtained from the same blood samples/healthy donors.
Project description:ER-phagy, a selective degradation of endoplasmic reticulum (ER) fragment, plays a critical role in maintaining the ER homeostasis. Dysregulation of ER-phagy is involved in the unfolded protein response (UPR), which serves as a vital clue to evoke inflammatory disease. However, the molecular mechanism underpinning the connection between ER-phagy and disease remains poorly defined. Here, we identified ubiquitin-associated domain-containing protein 2 (UBAC2) as an ER-phagy receptor, but a negative regulator of inflammatory responses. UBAC2 harbors a canonical LC3-interacting region (LIR) in the cytoplasmic domain that bind to autophagosomal GABARAP. Upon ER-stress or autophagy activation condition, microtubule affinity-regulating kinase 2 (MARK2) catalyzes the phosphorylation of UBAC2 at serine (S) 223 to promote its dimerization. Dimerized UBAC2 exhibits a stronger ability to interact with GABARAP for selective degradation of ER. Moreover, UBAC2 restrains inflammatory responses and acute ulcerative colitis (UC) in mice through affecting the ER-phagy. Our findings reveal ER-phagy directed by MARK2-UBAC2 axis can provide therapy target for inflammatory disease.