Perturb-Seq using T2D islets

Type 2 diabetes is associated with defective insulin secretion and reduced ß-cell mass. Available treatments provide a temporary reprieve, but secondary failure rates are high, making insulin supplementation necessary. Reversibility of b-cell failure is a key translational question. Here, we reverse-engineered and interrogated pancreatic islet-specific regulatory networks to discover T2D-specific subpopulations characterized by metabolic-inflexibility and endocrine-progenitor/stem cell features. Single-cell gain- and loss-of-function and glucose-induced Ca++ flux analyses of top candidate MR in islet cells validated transcription factor BACH2 and associated epigenetic effectors as a key driver of T2D cell states. BACH2 knockout in T2D islets reversed cellular features of the disease, restoring a non-diabetic phenotype. BACH2-immunoreactive islet cells increased ~4-fold in diabetic patients, confirming the algorithmic prediction of clinically relevant subpopulations. Treatment with a BACH inhibitor lowered glycemia and increased plasma insulin levels in diabetic mice, and restored insulin secretion in diabetic mice and human islets. The findings suggest that T2D-specific populations of failing b-cells can be reversed and indicate pathways for pharmacological intervention, including via BACH2 inhibition. Overall design: Adenovirus encoding CAS9_gRNAs targetting candidate TF with its corresponding DNA guide-barcode was infected in human T2D islets which are subjected to scRNA-seq.