Effect of Culture Conditions on Fetal Mouse Pancreas In Vitro and After Transplantation in Syngeneic and Allogeneic Recipients

Organ culture of fetal mouse pancreas under conditions designed to either maximally preserve islet cell survival or reduce immunogenicity was used to test the efficacy of islet graft function in diabetic syngeneic or fully allogeneic recipients. Organ culture in either 90% O₂, or at low temperature (22°C), or in a combination of 90% O₂ and 22°C for 14 days not only failed to reduce immunogenicity in fully allogeneic recipients but also diminished endocrine cell survival in grafts in syngeneic recipients. Monitoring of in vitro insulin secretion provided a better guide to future graft function than did the insulin content of the cultured tissue. It is concluded that culture conditions that have been shown to reduce immunogenicity (high O₂ concentration and low temperature) are not synergistic when used together and are also potentially damaging to endocrine cells.