Biological sensitivity to self-assembled nanomatrix platforms depends on the phenotype of MIN6 Β-cells

Pancreatic β-cell lines that possess the same native characteristics as insulin producing β-cells within islets of Langerhans have been widely used to evaluate newly developed scaffolds for the ultimate purpose of improving pancreatic islet transplantation (PIT). However, the morphological and functional characteristics of pancreatic β-cell lines in use are often overlooked; changes are gradually observed with each subsequent subculture of cells. Long-term cultured MIN6 β-cells that have alterations in morphology and function can lead to poor evaluation of newly proposed scaffolds. To investigate the influence of aged MIN6 β-cells in properly assessing a given scaffold, self-assembled nanomatrix platforms formed by peptide amphiphiles (PAs) that mimic native extracellular matrices (ECM) were made, and MIN6 β-cells of different subcultures were cultured for up to seven days. Compared to young MIN6 β-cells, old MIN6 β-cells showed reduced sensitivity in function to the self-assembled nanomatrix platform containing RGDS ligands. Young MIN6 β-cells displayed higher normalised insulin values than old MIN6 β-cells, indicating that the apparent functional performance of ECM-mimicking platforms depends not only on the ECM-mimicking ligands present but also on the condition of cells used to evaluate the ECM-mimicking platform. Moreover, the morphological differences were observed between young and old MIN6 β-cells. Overall, this study describes the importance of using suitable pancreatic β-cell lines in evaluating an ECM-mimicking platform for PIT.