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Kin, T.

Publications and source records attributed to Kin, T..

3 recordsLinked to original sources

Benchmarking porcine pancreatic ductal organoids for drug screening applications

Primary human pancreatic ductal organoids (HPDO) have emerged as a model to study pancreas biology and disease. Yet, donor material availability, and a lack of extensive benchmarking limits the range of applications. To address this gap, we established porcine pancreatic ductal organoids (PPDO) as a system from an easily obtainable source to model pancreatic ductal/progenitor biology. We benchmarked PPDO to HPDO and primary porcine pancreas using single-cell RNA sequencing (scRNA-Seq). We observed no overt phenotypic differences in PPDO derived from distinct developmental stages, with a WNT signaling enriched population characterizing PPDO. PPDO exhibited differentiation potential towards mature ductal cells and limited potential towards endocrine lineages. We used PPDO as a platform to assess the safety of FDA-approved drugs and showed conserved toxicity of statins and -adrenergic receptor inhibitors between PPDO and HPDO cultures. Overall, our results highlight the PPDO as a model for mammalian duct/progenitor applications.

developmental biology↗

Human research islet cell culture outcomes at the Alberta Diabetes Institute IsletCore

Human islets from deceased organ donors have made important contributions to our understanding of pancreatic endocrine function and continue to be an important resource for research studies aimed at understanding, treating, and preventing diabetes. Understanding the impacts of isolation and culture upon the yield of human islets for research is important for planning research studies and islet distribution to distant laboratories. Here we examine islet isolation and cell culture outcomes at the Alberta Diabetes Institute (ADI) IsletCore (n=197). Research-focused isolations typically have a lower yield of islet equivalents (IEQ), with a median of 252,876 IEQ, but a higher purity (median 85%) than clinically-focused isolations before culture. The median recovery of IEQs after culture was 75%, suggesting some loss. This was associated with a shift towards smaller islet particles, indicating possible islet fragmentation, and occurred within 24 hours with no further loss after longer periods of culture (up to 136 hours). No overall change in stimulation index as a measure of islet function was seen with culture time. These findings were replicated in a representative cohort of clinical islet preparations from the Clinical Islet Transplant Program at the University of Alberta. Thus, loss of islets occurs within 24 hours of isolation and there is no further impact of extended culture prior to islet distribution for research.

cell biology↗

Role of the G-Protein Coupled Receptor 3-Salt Inducible Kinase 2 Pathway in Human β CellProliferation

Loss of pancreatic {beta} cells is the hallmark of type 1 diabetes (T1D) 1, for which provision of insulin is the standard of care. While regenerative and stem cell therapies hold the promise of generating single-source or host-matched tissue to obviate immune-mediated complications2-4, these will still require surgical intervention and immunosuppression. Thus, methods that harness the innate capacity of {beta}-cells to proliferate to increase {beta} cell mass in vivo are considered vital for future T1D treatment5, 6. However, early in life {beta} cells enter what appears to be a permanent state of quiescence 7-10, directed by an evolutionarily selected genetic program that establishes a {beta} cell mass setpoint to guard against development of fatal endocrine tumours. Here we report the development of a high-throughput RNAi screening approach to identify upstream pathways that regulate adult human {beta} cell quiescence and demonstrate in a screen of the GPCRome that silencing G-protein coupled receptor 3 (GPR3) leads to human pancreatic {beta} cell proliferation. Loss of GPR3 leads to activation of Salt Inducible Kinase 2 (SIK2), which is necessary and sufficient to drive cell cycle entry, increase {beta} cell mass, and enhance insulin secretion in mice. Taken together, targeting the GPR3-SIK2 pathway represents a novel avenue to stimulate the regeneration of {beta} cells.

cell biology↗