Efficient transduction of pancreas tissue slices with genetically encoded calcium integrators

Lazimi, C. S.; Stis, A. E.; Panzer, J. K.; Hiller, H.; Beery, M. L.; Linnemann, A. K.; Stabler, C. L.; Mathews, C. E.; Phelps, E. A.

doi:10.1101/2025.03.21.644659

bioRxiv · 10.1101/2025.03.21.644659

Efficient transduction of pancreas tissue slices with genetically encoded calcium integrators

Lazimi, C. S.·Stis, A. E.·Panzer, J. K.·Hiller, H.·Beery, M. L.·Linnemann, A. K.·Stabler, C. L.·Mathews, C. E.·Phelps, E. A.

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Abstract

This study combines live pancreas tissue slices with viral transduction of the Calcium Modulated Photoactivatable Ratiometric Integrator 2 (CaMPARI2) biosensor for high-throughput analysis of islet calcium secretagogue responses. A key challenge of the pancreas slice model has been efficient transgene delivery throughout the slice volume while maintaining viability and function. Here, we demonstrate a robust adenoviral gene delivery approach to transduce slices with CaMPARI2 and apply photoconverting light to permanently mark glucose-induced calcium activity across all islets. This approach demonstrates glucose responsive CaMPARI2 labeling that correlates with insulin secretion. Using this novel high-throughput approach, we examine the relationship between islet size and calcium response. Larger isolated islets exhibit greater CaMPARI2 photoconversion in high glucose, whereas no size-function correlation is observed in islets resident in live slices. We also observe that slices capture a substantially higher proportion of small islets than isolated islets. Integrating CaMPARI2 with live pancreas slice studies enables multiplexed analyses, linking functional readouts to spatial features.

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Lazimi, C. S., Stis, A. E., Panzer, J. K., Hiller, H., Beery, M. L., Linnemann, A. K., Stabler, C. L., Mathews, C. E., Phelps, E. A.. 2025-03-25. Efficient transduction of pancreas tissue slices with genetically encoded calcium integrators. https://doi.org/10.1101/2025.03.21.644659

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