The isolation and transplantation of foetal mouse proislets.

A method is described for the isolation of "proislets' from mouse foetal pancreas. Histologically, isolated proislets are composed of undifferentiated tissue which does not stain with aldehyde fuchsin. Following isotransplantation, proislets develop into well differentiated islets with beta cell granulation. In addition, isografts consisting of proislets harvested from 8 foetal mouse pancreases have the functional capacity to reverse Streptozotocin-induced diabetes. Proislets appear to represent foetal precursor islet tissue.