IMMUNOMAGNETIC ISOLATION OF ISLETS FROM THE RAT PANCREAS

Islets were selectively isolated from rat pancreatic digests using mag netic microspheres coated with anti-islet monoclonal antibodies. The i solation process was optimized as a function of bead concentration and time of incubation with the tissue digest. Apparent and normalized is let yields of 92 +/- 6% and 81 +/- 7%, respectively, were obtained by incubating the digests with 10(7) beads/ml for 40 min followed by isol ation of the bead-coated islets under a magnetic field. While some fra gmentation occurred, the isolation process did not alter islet functio nality as demonstrated by an insulin secretion response to glucose sti mulation equivalent to that of handpicked controls. The technique is f ast, reproducible, and potentially scaleable to larger pancreases as a secondary purification step.