Insulin deficiency distorts human pancreatic endocrine cell composition during development

ABSTRACT: Objective: The developmental effects of mutations in genes associated with monogenic diabetes on human pancreas development is not well understood. More specifically, if insulin gene recessive mutations influence the human endocrine lineage segregation still needs to be investigated. Methods: We generated a novel knock-in H2B-Cherry reporter human induced pluripotent stem cell (iPSCs) line expressing no insulin upon differentiation to stem cell-derived (SC-) β cells in vitro. This cell line enabled us to have a model mimicking the extremely reduced insulin levels in patients with recessive insulin mutations. We combined immunostaining, Western blotting and proteomics analysis to characterize the SC-islets from this iPSC line. Furthermore, we leveraged FACS analysis and imaging to explore the impact of insulin shortage on human endocrine cell induction, composition and proliferation. Results: We found that lack of insulin hampers insulin receptor (IR) signaling in SC-islets but increases the IR sensitivity. Furthermore, insulin deficiency showed no effects on human endocrine lineage induction. However, lack of insulin skewed the SC-islet cell composition. We found an increased in SC-β cell number at the expense of SC-α cell differentiation in the absence of insulin. Finally, insulin shortage reduced the rate of SC-β cell proliferation but had no impact of the expansion of SC-α cells. Conclusions: We provided evidence of the developmental impacts of reduced insulin levels on human β cell characteristics and endocrine lineage formation. These findings help to better understand the pathomechanisms of recessive insulin mutations during embryonic development and also shed some lights on the possible physiological function of this hormone coordinating human islet cell composition and architecture during endocrinogenesis.

INSTRUMENT(S): Orbitrap Exploris 480

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Pluripotent Stem Cell, Fibroblast

SUBMITTER: Natalie Krahmer  

LAB HEAD: Natalie Krahmer

PROVIDER: PXD045366 | Pride | 2024-01-17

REPOSITORIES: Pride