The present invention includes compositions and methods for the preparation, preservation and storage of organs (e.g., pancreatic islet cells) for transplantation by storing organs in which the organs are suspended in a solution for maintaining viability and the organ or cells are cooled in a refrigeration unit for the entire duration of storage in which the average temperature in the apparatus does not vary by more than 2 degrees centigrade from the set temperature.本発明は、生存性を維持するために臓器を溶液中に保持し、且つ、全貯蔵期間を通して臓器又は細胞を冷蔵装置内で冷却し、その際の器具内の平均温度の設定温度からの変化が摂氏2度以内である臓器の貯蔵による、移植用臓器(例えば膵島細胞)の調製、保存及び貯蔵のための構成及び方法を含む。