ENCAPSULATED BETA-ISLET CELLS AS A BIOARTIFICIAL PANCREAS TO TREAT INSULIN-DEPENDENT DIABETES DURING PREGNANCY

OBJECTIVE: Our purpose was to determine the effectiveness of the bioar tificial pancreas technique in correcting (I) maternal carbohydrate me tabolism and (2) fetal malformation rates in a pregnant diabetic anima l model. STUDY DESIGN: Insulin secretion from encapsulated rat islets cultured in the presence of homologous rat prolactin was determined an d compared with that of controls. Streptozotocin-induced diabetic Balb /c mice were then transplanted with rat islet cells encapsulated withi n alginate microbeads and were then bred. Blood glucose determinations were made after transplantation and throughout gestation. Pups were d elivered by cesarean section on day 19 of gestation. Outcome parameter s from the transplanted study animals were compared with those of nond iabetic controls and untreated diabetic animals. RESULTS: Insulin secr etion was increased twofold in encapsulated rat islets exposed to pro[ actin compared with control values. Throughout gestation maternal weig hts and blood glucose levels of transplanted animals were similar to t hose of nondiabetic controls. A fetal malformation rate of only 1.4% w as observed in the pups from transplanted animals. CONCLUSIONS: Transp lanted encapsulated islets are capable of normalizing maternal carbohy drate metabolism in a pregnant diabetic animal model. This therapy, if instituted before conception, also appears to eliminate the increase in fetal malformations seen in diabetic pregnancies.