Adipose-derived StromalCells Preserve Pancreatic Islet Function in a Transplantable 3D Bioprinted Scaffold

Intra-portal islet transplantation is currently the only clinically approved beta cell replacement therapy, but its outcome is hindered by limited cell survival due to a multifactorial reaction against the allogeneic tissue in liver. Adipose-derived stromal cells (ASCs) can potentially improve the islet micro-environment by their immunomodulatory action. The challenge is to combine both islets and ASCs in a relatively easy and consistent long-term manner in a deliverable scaffold. W e report on manufacturing the Three-dimensional (3D) bioprinted double-layered scaffolds with primary islets and ASCs using a mix of alginate/nano-fibrillated cellulose (NFC) bioink. W e demonstrate the diffusion properties of the bioink and the supportive effect of human ASCs on islet viability, glucose sensing, insulin secretion and reducing the secretion of pro-inflammatory cytokines. Diabetic mice transplanted with islet-ASC scaffolds reached normoglycemia 7 days post transplantation with no significant difference between this group and the group received islets under the kidney capsules. In addition, animals transplanted with islet-ASC scaffolds stayed normoglycemic and showed elevated levels of C-peptide compared to mice transplanted with islet-only scaffolds. Our data presents a functional 3D bioprinted scaffold for islets and ASCs transplanted to the extrahepatic site and suggest a possible role of ASCs on improving the islet micro-environment.