Assessment of insulin secretion and content in vitro

Standard aliquots of 50 islets equivalent (IEQ) or 100 IEQ of ILIPAs were incubated for 60 min with low glucose (60 mg/dL, basal), followed by 60 min of high glucose (300 mg/dL, stimulated).¹⁶ Following high-glucose incubation, islets were harvested and insulin was extracted in an ethanol–acid solution (165 mM HCl in 75% ethanol). The islets were then analyzed for insulin content using a specific enzyme-linked immunosorbent assay (ELISA) assay (ALPCO Diagnostics, Windham, NH). The low-glucose medium used was standard alpha MEM supplemented with 5% platelet lysate (PL). The high-glucose stimulation medium was high-glucose D-MEM (450 mg/dL glucose) supplemented with 5% PL.