https://www.jci.org/articles/view/190034
Curing autoimmune diabetes (type I / type 1) in mice with islet and hematopoietic cell transplantation after CD117 antibody-based conditioning
Abstract
Mixed hematopoietic chimerism after allogeneic hematopoietic cell transplantation (HCT) promotes tolerance of transplanted donor-matched solid organs, corrects autoimmunity, and could transform therapeutic strategies for autoimmune type 1 diabetes (T1D). However, development of nontoxic bone marrow conditioning protocols is needed to expand clinical use. We developed a chemotherapy-free, nonmyeloablative (NMA) conditioning regimen that achieves mixed chimerism and allograft tolerance across MHC barriers in NOD mice. We obtained durable mixed hematopoietic chimerism in prediabetic NOD mice using anti–CD117 monoclonal antibody, T cell depleting antibodies, JAK1/2 inhibition, and low-dose total body irradiation prior to transplantation of MHC-mismatched B6 hematopoietic cells, preventing diabetes in 100% of chimeric NOD:B6 mice. In overtly diabetic NOD mice, NMA conditioning followed by combined B6 HCT and islet transplantation durably corrected diabetes in 100% of chimeric mice without chronic immunosuppression or graft-versus-host disease (GVHD). Chimeric mice remained immunocompetent, as assessed by blood count recovery and rejection of third-party allogeneic islets. Adoptive transfer studies and analysis of autoreactive T cells confirmed correction of autoimmunity. Analysis of chimeric NOD mice revealed central thymic deletion and peripheral tolerance mechanisms. Thus, with NMA conditioning and cell transplantation, we achieved durable hematopoietic chimerism without GVHD, promoted islet allograft tolerance, and reversed established T1D.
https://www.news-medical.net/news/20251118/New-transplant-approach-resets-the-immune-system-to-stop-Type-1-diabetes.aspx
New transplant approach resets the immune system to stop Type 1 diabetes
A combination blood stem cell and pancreatic islet cell transplant from an immunologically mismatched donor completely prevented or cured Type 1 diabetes in mice in a study by Stanford Medicine researchers. Type 1 diabetes arises when the immune system mistakenly destroys insulin-producing islet cells in the pancreas.
None of the animals developed graft-versus-host disease - in which the immune system arising from the donated blood stem cells attacks healthy tissue in the recipient - and the destruction of islet cells by the native host immune system was halted. After the transplants, the animals did not require the use of the immune suppressive drugs or insulin for the duration of the six-month experiment.
The possibility of translating these findings into humans is very exciting. The key steps in our study - which result in animals with a hybrid immune system containing cells from both the donor and the recipient - are already being used in the clinic for other conditions. We believe this approach will be transformative for people with Type 1 diabetes or other autoimmune diseases, as well as for those who need solid organ transplants."
Seung K. Kim, MD, PhD, the KM Mulberry Professor and professor of developmental biology, gerontology, endocrinology and metabolism
Kim, who directs the Stanford Diabetes Research Center and the Northern California Breakthrough T1D Center of Excellence, is the senior author of the study, which published online Nov. 18 in the Journal of Clinical Investigation. Graduate and medical student Preksha Bhagchandani is the lead author of the research.