Application of cryopreservation techniques to islet cell allotransplantation.

This study continues our investigations in the area of canine islet cell cryopreservation. Islet cell allografts were frozen using a simple method to -196 degrees C with rapid freezing rates and dimethyl sulfoxide as the cryoprotectant. Good in vitro viability was observed using trypan blue dye exclusion. After intrasplenic transplantation, grafts which did not reject were able to maintain normoglycemia for periods of greater than 60 days. The use of either Cy A as an immunosuppressant or ALG as a graft pretreatment contributed to prolongation of allograft survival in these long-term surviving recipients. These results encourage further studies in this area for potential future clinical application of this technique to human pancreas.