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bioRxiv · 10.1101/2024.11.19.624394

Controlling human stem cell-derived islet composition using magnetic sorting

Kelley, A. B.·Shunkarova, M.·Maestas, M. M.·Gale, S. E.·Hogrebe, N. J.·Millman, J. R.
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Abstract

Stem cell-derived islets (SC-islets) consists of multiple hormone-producing cell types and offer a promising therapeutic avenue for treating type 1 diabetes (T1D). Currently, the composition of cell types generated within these SC-islets currently cannot be controlled via soluble factors during this differentiation process and consist of off-target cell types. In this study, we devised a magnetic-activated cell sorting (MACS) protocol to enrich SC-islets for CD49a, a marker associated with functional insulin-producing {beta} cells. SC-islets were generated from human pluripotent stem cells (hPSCs) using an adherent differentiation protocol and then sorted and aggregated into islet-like clusters to produce CD49a-enriched, CD49a-depleted, and unsorted SC-islets. Single-cell RNA sequencing (scRNA-seq) and immunostaining revealed that CD49a-enriched SC-islets had higher proportions of {beta} cells and improved transcriptional identity compared to other cell types. Functional assays demonstrated that CD49a-enriched SC-islets exhibited enhanced glucose-stimulated insulin secretion both in vitro and in vivo following transplantation into diabetic mice. These findings suggest that CD49a-based sorting significantly improves {beta} cell identity and the overall function of SC-islets, improving their effectiveness for T1D cell replacement therapies.

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Kelley, A. B., Shunkarova, M., Maestas, M. M., Gale, S. E., Hogrebe, N. J., Millman, J. R.. 2024-11-21. Controlling human stem cell-derived islet composition using magnetic sorting. https://doi.org/10.1101/2024.11.19.624394

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