Project description:Islet transplantation to treat the late stage of T1DM patients has made some inspiring success recently in clinical trials. However, most of patients underwent a decline of islet cell graft in one to three years due to chronic immune rejection. Although the mechanisms of immune cells including macrophages, dendritic cells (DCs), neutrophils, natural killer cells (NKs), B cells, T cells that mediate immune rejection have been investigated, the overall characteristics of immune infiltrates in islet allografts remain unclear. Single-cell RNA sequencing (scRNA-seq) has provided us with new opportunities to study the molecular characteristics of the immune microenvironment in islet transplants. In the present study, we used scRNA-seq to comprehensively analyze the immune heterogeneity in islet graft, and compared the variances regarding to transcriptomal profiling and immune atlas between syngeneic islet transplantation and allograft.
Project description:The intrahepatic milieu is inhospitable to intraportal islet allografts, limiting their applicability to ameliorate Type 1 Diabetes (T1D). Islet viability in the subcutaneous space represents an unfulfilled paradigm that is crucial to ensure widespread adoption and safety of clinical islet transplantation. Herein we report that human islets transplanted subcutaneously uniformly promote long-term euglycemia when admixed with a device-free Islet Viability Matrix (IVM), through a previously unknown anti-apoptotic mechanism.
Project description:Acute graft versus host disease is a serious condition caused by allo-reactive donor CD4+ T cells from allogenic hematopoietic stem cell transplantation. To understand the developmental relationships between T-helper states in mesenteric lymph nodes (mLN), TCR transgenic CD4+ T cells specific for a single allo-peptide (TEa cells) from mice were recovered at Days 0, 1, 2, 3, and 4 from mLN, and Day 5 from the gut and underwent processing to generate scRNA-seq dataset. TEa cells were also recovered at Day 5 from mLN and were either treated with and without IEL-isolation pre-digestion buffer as controls.
Project description:Mouse pancreatic islet scRNA-seq integrated atlas encompassing different ages, sexes, chemical stress leading to dedifferentiation, and diabetes models with corresponding treatments. Two datasets (sub-series) were newly generated for the atlas.
Project description:From the past reports, we hypothesized that spleen is an ideal site for inducing regeneration of transplanted islets, and leading to reduce the required number of islets for ameliorating the hyperglycemia of diabetic recipients in mice. In order to confirm this hypothesis, we performed 25 islets transplantation into spleen (SP25); it was not enough number to ameliorate the hyperglycemia of recipient mice, with 100 islets transplantation into beneath the kidney capsule (KC100) to maintain recipients' blood glucose normoglycemic temporary. All recipient mice (n=11) became normoglycemic after receiving SP25 with KC100. On 240 days after transplantation, we performed nephrectomy for removing islet grafts in the kidney. After nephrectomy, 8 of 11 mice remained normoglycemic, and 3 of 11 mice' non-fasting blood glucose levels were maintained around 300 mg/dL. On 290 days after transplantation (50 days after nephrectomy), all recipient mice received splenectomy to remove islet grafts in the spleen. All mice became hyperglycemic after splenectomy, indicating that intra-splenic islet grafts maintained the blood glucose levels of diabetic recipient mice. In order to investigate the gene expression associated with islets engraftment in the spleen, microarray studies were performed in comparison of the Tlx-1 (Hox11) related gene expression profiles of Sample 1, Sample 2 and Sample 3.
Project description:The aim of this study is to assess the Fecal Microbiota Transplantation (FMT) efficacy in the prevention of allogeneic hematopoietic stem cell transplantation (allo-HSCT) complications and particularly Graft versus Host Disease (GvHD).
The hypothesis of this study is that allogeneic FMT may improve outcomes of these patients.
Project description:Loss of pancreatic beta cells is the central feature of all forms of diabetes. Current therapies fail to halt the declined beta cell mass. Thus, strategies to preserve beta cells are imperatively needed. In this study, we identified paired box 6 (PAX6) as a critical regulator of beta cell survival. Under diabetic conditions, the human beta cell line EndoC-bH1, db/db mouse and human islets displayed dampened insulin and incretin signalings and reduced beta cell survival, which were alleviated by PAX6 overexpression. Adeno-associated virus (AAV)-mediated PAX6 overexpression in beta cells of streptozotocin-induced diabetic mice and db/db mice led to a sustained maintenance of glucose homeostasis. AAV-PAX6 transduction in human islets reduced islet graft loss and improved glycemic control after transplantation into immunodeficient diabetic mice. Our study highlights a previously unappreciated role for PAX6 in beta cell survival and raises the possibility that ex vivo PAX6 gene transfer into islets prior to transplantation might enhance islet graft function and transplantation outcome.
Project description:To illustrate the immune cell atlas and functional heterogeneity of T cell repertoire in murine heart transplantation,we established the murine heterotopic heart transplantation model and isolated CD45 positive cells from cardiac grafts and spleens for single cell transcriptome and TCR sequencing.
Project description:The islet primary non-function (PNF) is a serious problem in islet transplantation. In this study, we investigated whether DcR3-secreting transgenic (Tg) islets could reduce PNF. We generated transgenic mice expressing human DcR3. The transgenically expressed DcR3 protected islets from IFN-gama plus IL-1beta, or TNF-alpha plus IL-1beta-induced dysfunction and apoptosis in vitro. The Tg islets presented significantly reduced PNF after transplantation. <br><br> Three independent batches of islet isolation were carried out. For each batch, islets were obtained from 4 Tg and 4 WT mice, and pooled respectively. The pooled islets (Tg or WT) were then divided into 4 groups: 2 were cultured in the presence of IFN-gamma (0.5 ug/ml) plus IL-1beta (0.5 ng/ml) with 1 harvested at 24 h and 1 harvested at 48 h; 2 were cultured in the presence of TNF-alpha (100 ng/ml) plus IL-1beta (0.5 ng/ml) with 1 harvested at 24 h and 1 harvested at 48 h. Each treatment employed 3 chips using RNA from 3 different batches of islet isolation. For each treatment, genes with a mean signal strength difference above 2-fold between Tg and WT islets were selected for reverse PCR confirmation.