1028-OR: Senotype Blueprint of the Human Endocrine Pancreas

Introduction and Objective: Senescence (SnC) is a complex cellular response with important pathophysiological roles in aging and age-related diseases, type 2 diabetes. Heterogeneity of Senescent Cells (SnCs) and their associated senescence-associated secretory phenotype (SASP) underline the biological basis of cell and tissue-specific senotypes, but these remain to be fully characterized. As part of the Cellular Senescence Network (SenNet), a National Institutes of Health Common Fund initiative, we generated a blueprint of the senotypes in the human endocrine pancreas across the human lifespan. Methods: By using whole pancreas and dispersed pancreas (islet, acinar, duct cells) from 11 heart beating brain dead donors and 13 donors, respectively, we used spatial transcriptomics (Visium, Xenium), proteomics (CODEX), scRNASeq, static and dynamic evaluation of insulin secretion and proteomic analysis of SASP to define senescent subpopulations in the endocrine human pancreas. Results: We identified two discrete senotypes, distinguished by relative CDKN1A and CDKN2A expression. Transcriptional profiling revealed loss of cellular identity in CDKN1A+/CDKN2A - SnCs, that was associated with dysfunctional insulin secretion and a proinflammatory SASP, reflected in increased islet immune infiltration. In contrast, CDKN1A-/CDKN2A+ SnCs had preserved transcriptional identity and function. Cell proximity and communication assays underscored crosstalk between senescent β-cells and both acinar and endothelial cells. Conclusion: The human endocrine pancreas has a physiological (CDKN1A-/CDKN2A+) and a pathological (CDKN1A+/CDKN2A- ) senotype, whose identification increases our understanding of the role of SnCs during human life and can lead to senotype-specific therapeutic interventions. Hence, the generation of a senotype blueprint of the human endocrine pancreas revealed diverse senescence signatures, underscored their biological relevance, and will inform senotherapeutic strategies for metabolic and overall human health. Disclosure K. Iwasaki: None. H. Pan: None. J. Dreyfuss: None. S. Domanskyi: None. D. Baker: None. P. Carapeto: None. C. Cahill: None. S. Le: None. F. Hela: None. J. Alcoforado: None. G. Eryilmaz: None. F. Wu: None. P. Wu: None. B. Yu: None. D. Wirtz: Stock/Shareholder; Current; Abmeta. A. Pena: None. F.G. Cigarroa: None. G.A. Abrahamian: None. J. Woodworth: None. P.D. Adams: None. J. Chuang: None. V. Garovic: None. J.L. Kirkland: Other - Speaker; Ended; GlaxoSmithKline plc. T. Tchkonia: None. N. Musi: None. G.A. Kuchel: None. C. Aguayo-Mazzucato: Consultant; Ended; Novo Nordisk, Sanofi. Funding National Institutes of Health (U54AG075941, 1R01DK132535, P30 DK036836, UH3CA275681, R37AG013925, R33AG061456, R33AG061456), Thomas J Beatson Jr Foundation grant 2025-020, the Richard and Susan Smith Family Foundation Award, Hevolution Foundation grant (HF-GRO-23-1199148-3), the Connor Fund, and Robert J. and Theresa W. Ryan