Simultaneous LC-MS determination of glucose regulatory peptides secreted by stem cell-derived islet organoids

Olsen, C.; Wang, C.; Aizenshtadt, A.; Abadpour, S.; Lundanes, E.; Skottvoll, F. S.; Golovin, A.; Busek, M.; Krauss, S.; Scholz, H.; Wilson, S. R.

doi:10.1101/2023.06.12.544566

bioRxiv · 10.1101/2023.06.12.544566

Simultaneous LC-MS determination of glucose regulatory peptides secreted by stem cell-derived islet organoids

Olsen, C.·Wang, C.·Aizenshtadt, A.·Abadpour, S.·Lundanes, E.·Skottvoll, F. S.·Golovin, A.·Busek, M.·Krauss, S.·Scholz, H.·Wilson, S. R.

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Abstract

For studying stem cell-derived islet organoids (SC-islets) in an organ-on-chip platform, we have developed a reversed phase liquid chromatography tandem mass spectrometry (RPLC-MS/MS) method allowing for simultaneous determination of insulin, somatostatin-14, and glucagon, with improved matrix robustness compared to earlier methodology. Combining phenyl/hexyl-C18 separations using 2.1 mm inner diameter LC columns and triple quadrupole mass spectrometry, identification and quantification were secured with negligible variance in retention time and quantifier/qualifier ratios, negligible levels of carry-over (< 2%), and sufficient precision ({+/-} 10% RSD) and accuracy ({+/-} 15% relative error) with and without use of internal standard. The here developed RPLC-MS/MS method showed that the SC-islets have an insulin response dependent on glucose concentration, and the SC-islets produce and release somatostatin-14 and glucagon. The RPLC-MS/MS method for these peptide hormones was compatible with an unfiltered off-line sample collection from SC-islets cultivated on a pump-less, recirculating organ-on-chip (rOoC) platform. The SC-islets background secretion of insulin was not significantly different on the rOoC device compared to a standard cell culture well-plate. Taken together, RPLC-MS/MS is well suited for multi-hormone measurements of SC-islets on an organ-on-chip platform.

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Olsen, C., Wang, C., Aizenshtadt, A., Abadpour, S., Lundanes, E., Skottvoll, F. S., Golovin, A., Busek, M., Krauss, S., Scholz, H., Wilson, S. R.. 2023-06-12. Simultaneous LC-MS determination of glucose regulatory peptides secreted by stem cell-derived islet organoids. https://doi.org/10.1101/2023.06.12.544566

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