ABSTRACT

Type 1 diabetes (T1D) is an autoimmune disorder leading to the destruction of insulin-producing β-cells in the pancreas. Despite recent scientific advances, questions remain regarding the initial trigger and the downstream mechanisms of disease progression. Human induced pluripotent stem cells (hiPSCs) provide new opportunities for cell replacement therapy of T1D. Therapeutic quantities of human stem cell-derived β-cells (SC-β) can be attained in vitro following a stepwise differentiation protocol. Yet, preventing immune rejection of grafted cells, without the use of life-long immunosuppressants, remains a major challenge. Using T1D patients' hiPSC derived β-cells (iPSC-β), we developed a human in vitro platform in an autologous setting that recapitulates aspects of the effector/target interactions in an autoimmune response. A donor-matched β-cell-specific response was achieved by co-cultures with perihelial blood mononuclear cells (PBMCs) derived from the same donors' blood. We performed a droplet based single-cell RNA sequencing (scRNA-seq) of T1D iPSC-β co-cultured with their autologous PBMCs. scRNA-seq data analysis of co-cultured cell populations identified upregulated genes that contribute to the inflammatory microenvironment of a T1D pancreatic islet. Subsequent co-culture experiments have shown that CRISPR-depletion of such genes in SC-β, can reduce activation of T-cells and increase β-cell survival. These results provide insights into the nature of immune destruction of β-cells during T1D and suggest a path to prevent it in cell replacement approaches.