Bioprinting of Prevascularized Beta-cell Sheet to Improve Islet Transplantation

Abstract

Type I diabetes is an incurable autoimmune disease, which is failure in producing sufficient insulin because of loss of b cells in pancreas. Islet transplantation has been considered as a viable option for healing the disease. However, absence of vascular network and low mechanical stability of islet construct are still big obstacles in its clinic applications. Therefore, the way to fabricate prevascularized b-cell construct having reliable stability was studied to overcome the difficulties in this research. Mouse insulinoma cell line 6 (Min6), human umbilical vein endothelial cells (HUVEC) and polycaprolactone (PCL) were applied to fabricate a prevascularized b-cell laden sheet by co-bioprinting of the multiple materials. Min6 and HUVEC laden hydrogel were printed individually within PCL lattice structure having 300mm channel. Time-series micrographs of vessel formation within the sheet was observed. And viability, proliferation and functionality test of b cells were also conducted to show its usefulness. These results successfully demonstrated that the bioprinted b cell sheet having prevascular structures has great potential to treat type I diabetes in clinics.