Proteome and Transcriptome Characterization of Pancreatic α, β, and δ-cells Using Laser Microdissection Microscopy

Diabetes is characterized by β-cell loss over time. Therefore, regenerating β-cells is considered the holy grail of diabetes therapy. We demonstrated that pancreatic injury of acinar cell damage induced by caerulein led to islet cell transdifferentiation from α-cells to β-cells. Caerulein plus β-cell ablation generated α- to β-cell transdifferentiation, with many β-cells further transdifferentiating into δ-cells.

Our goal is to stabilize the neogenic β-cells and prevent the continued differentiation into δ-cells. The problem is that we know little about what makes a δ-cell, as for the three pancreatic primary endocrine cell types, the δ-cells are the least studied. Therefore, we aim to investigate what differentiates α- and δ-cells from each other and from β-cells and use these findings to explore ways to stabilize the β-cell intermediate during the α- to β- to δ-cell transdifferentiation process.

To find the differences between α, β, and δ-cells, we used Laser Microdissection (LMD7) technology. This technology employs a high-energy laser source, which we can manually aim to separate the desired cells from the tissue section. We designed the laser to cut individual cells and concentrate them by type in different Eppendorf tubes, enabling isolation and downstream analysis. We successfully established a high-sensitivity protocol for isolating islet cell populations for proteomic and transcriptomic studies. We will introduce the methodology in the presentation, compare it to other laser capture microscopy methods, and share the mass-spec as well as the sequencing results we obtained.