Pig pancreatic islet transplantation into spontaneously diabetic dogs.
BACKGROUND
Pig islet xenotransplantation represents an attractive way to solve our human organ shortage. In this preclinical protocol, we implanted adult porcine islets microencapsulated in alginate-polylysin into insulin-dependent diabetic dogs.


METHODS
Pancreata were obtained from animals weighing 100 to 150 kg in a slaughterhouse. The islets were isolated by collagenase digestion. The encapsulation technique was a modification of Sun's method. Isolated islets (5000 islet equivalents per kilogram of dog weight) were mixed with 1.6% low-viscocity alginate. Microcapsules were cultured for 36 hours before implantation. The five dogs were in healthy prior to induction of diabetes mellitus at least 1 year prior. Under sedation, we implanted microcapsules. We performed determinations of peripheral blood insulin at baseline and every 3 months as well as glycosylated hemoglobin at baseline and every 4 months. During follow-up, glycemia was estimated twice a day at 3 hours after morning and night meals using a blood glucose monitoring system.


RESULTS
We observed significant decrease (20%-80%) in insulin needs (P < .01). Of note, before the procedure no hormone was detected in the blood at 6 to 12 months after transplantation, plasma insulin had improved significantly (P < .05) and glycosylated hemoglobin also showed a significant decrease (P < .01). All owners subjectively claimed that their animals were enjoying a better quality of life.


CONCLUSIONS
Our preliminary data suggested that pig islet microencapsulation achieved metabolic control in type I diabetic dogs without the risk of immunosuppression using one or two procedures per year.
Abalovich
A G
AG
Universidad de San Martín, Escuela de Ciencia y Tecnología, Buenos Aires, Argentina. abla@ciudad.com.ar
Bacqué
M C
MC
Grana
D
D
Milei
J
J
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D002214:Capsules; D018929:Cell Culture Techniques; D003920:Diabetes Mellitus / Q000097:blood / Q000188:drug therapy / Q000601:surgery* / Q000662:veterinary*; D004283:Dog Diseases / Q000097:blood / Q000188:drug therapy / Q000601:surgery*; D004285:Dogs; D006085:Graft Survival; D007328:Insulin / Q000097:blood / Q000378:metabolism* / Q000627:therapeutic use; D000078790:Insulin Secretion; D016381:Islets of Langerhans Transplantation / Q000379:methods*; D013552:Swine; D014183:Transplantation, Heterologous / Q000379:methods*
D001786:Blood Glucose; D002214:Capsules; D007328:Insulin