Project description:T cells infiltrate pancreatic islets during the progression of type 1 diabetes (T1D) but their differentiation states have not been completely defined. We used unbiased single-cell RNA sequencing analyses to gain further insight into the phenotypic complexity of islet-infiltrating T cells in non-obese diabetic (NOD) mice.
Project description:Pancreas specific deletion of the Haster promoter region results in a variegated phenotype in pancreatic islets with overexpression or silencing of the Hnf1a gene. To determine the transcriptional consequence of the overexpression or silencing of Hnf1a is islet cells from the Haster pKO mice (Haster loxP/loxP;Pdx1-Cre), we performed scRNA-seq of pancreatic islets from control and adult female Haster pKO mice.
Project description:In type 1 diabetes (T1D) autoreactive CD8 T cells infiltrate pancreatic islets and destroy insulin-producing β cells. Progression to T1D onset is a chronic process, which suggests that the effector activity of β-cell autoreactive CD8 T cells needs to be maintained throughout the course of disease development. The mechanism that sustains diabetogenic CD8 T cell effectors during the course of T1D progression has not been completely defined. Here we used single-cell RNA sequencing to gain further insight into the phenotypic complexity of islet-infiltrating CD8 T cells in NOD mice. We identified two functionally distinct subsets of activated CD8 T cells, CD44highTCF1+CXCR6- and CD44highTCF1-CXCR6+, in islets of prediabetic NOD mice. Compared to CD44highTCF1+CXCR6- CD8 T cells, the CD44highTCF1-CXCR6+ subset expressed higher levels of inhibitory and cytotoxic molecules and was more prone to apoptosis. Adoptive cell transfer experiments revealed that CD44highTCF1+CXCR6- CD8 T cells, through continuous generation of the CD44highTCF1-CXCR6+ subset, were more capable than the latter population to promote insulitis and the development of T1D. We further showed that direct interleukin-27 (IL-27) signaling in CD8 T cells promoted the generation of terminal effectors from the CD44highTCF1+CXCR6- population. These results indicate that islet CD44highTCF1+CXCR6- CD8 T cells are a progenitor-like subset with self-renewing capacity and under an IL-27 controlled mechanism they differentiate into the CD44highTCF1-CXCR6+ terminal effector population. Our study provides new insight into the sustainability of the CD8 T cell response in the pathogenesis of T1D.
Project description:To gain insights into how pancreatic cells are programmed in vivo, we profiled Ring1b in embryonic stem cells and pancreatic islets
Project description:Previous study (Segerstolpe Å et.al., Cell Metab . 2016) has revealed the single-cell landscape of human pancreatic islets from 10 human individuals. Here, we have performed Smart-seq2 scRNA-seq of additional 4 healthy and 6 T2D individuals.
Project description:To gain insights into how pancreatic cells are programmed in vivo, we profiled RNA expression in pancreatic islets of pancreatic Ring1b conditional KO mice (conditional using a pancreas specfic Cre; Pdx1-Cre) and their littermate controls
Project description:Pancreatic islet cells derived from human pluripotent stem cells hold great promise for modeling and treating diabetes. Differences between stem cell-derived and primary islets remain, but molecular insights to inform improvements are limited. Here, we acquire single-cell transcriptomes and accessible chromatin profiles during in vitro islet differentiation and from primary childhood and adult pancreas for comparison. We delineate major cell types, define their regulomes, and describe spatiotemporal regulatory relationships between transcription factors. CDX2 emerged as a regulator of enterochromaffin-like cells, which we show resemble a previously unrecognized, transient CDX2-expressing β-cell-related population in fetal pancreas, arguing against a non-pancreatic origin as proposed. Furthermore, we observe insufficient activation of signal-dependent transcriptional programs during in vitro β-cell maturation and identify sex hormones as drivers of childhood β-cell proliferation. Altogether, our analysis provides a comprehensive understanding of cell fate acquisition in stem cell-derived islets and a framework for manipulating cell identities and maturity.