Efficacy of a new collagenase for canine and murine islet isolation

ELSEVIER

Efficacy of a New Collagenase S. Ohtsuka,

T. Kawahara,

for Canine and Murine Islet Isolation

S. Arita, S. Une, L. Shevlin,

C

OLLAGENASE is one of the critical agents for obtaining a large quantity of high quality islets for transplantation. Although the quality has greatly improved, the performance of collagenase is differs from lot to lot produced. A new collagenase, manufactured by Yakult, Japan, has been reported to have minimal variability. In this study, we evaluated Yakult collagenase for murine and canine pancreatic islet isolation. MATERIALS AND METHODS Murine islet Isolation Islets were isolated from BALB/c mouse pancreata by ductal infusion of HBSS containing 1.5 mgimL of Yak& collagenase (two lots) (group 1) or 1 mg/mL of collagenase-P (lots #99 and #20; Boehringer Mannheim, Indianapolis, Ind) (group 2), followed by stationary incubation at 37°C. Islets were separated on Ficoll and then handpicked. Islets from both groups were transplanted under the renal capsule of syngeneic mice made diabetic with streptozotocin (250 mgikg). Canine

RESULTS

range

islets/pancreas with a range of 130 to 260 (n = 29) in group 2. With both Yakult collagenase and collagenase-P, there was no significant difference in islet yields between different lots. Islets in both groups responded well, in vitro, to insulin release with high glucose stimulation. Isografts in both groups reversed diabetes. The canine islet yield was 1692 -C 776 IEQ/g of pancreas with Yakult and 4445 ? 1874 IEQ/g with collagenase-P. Yakult collagenase yielded high numbers of islets from mouse pancreata without significant differences between lots. It yielded a reasonable number of islets from canine pancreata, but required a higher concentration of collagenase than collagenase-P.

REFERENCE 1. Kenmochi T, Miyamoto Proc 26:3412, 1994

M, Nakagawa

Y, et al: Transplant

Islet Isolation

Each pancreas head was divided into two portions, and islets were isolated using our two-step digestion method,’ with Yakult collagenase (3 mg/mL) for one portion and collagenase-P (2 mg/mL) for the other.

The

and Y. Mullen

AND

CONCLUSION

mouse islet yield was 227 ? 59 islets/pancreas with a of 146 to 367 (n = 30) in group 1 and 203 ? 37

0 1997 by Elsevier Science Inc. 655 Avenue of the Americas, New York, NY 10010

Transplantation Proceedings, 29, 1961 (1997)

From the Human Islet Program, Department of Surgery, UCLA School of Medicine and VAMC West Los Angeles, California, USA. Supported by a grant from Islet Technology, Inc, North Oaks, Minnesota. Address reprint requests to Dr S. Ohtsuka, Department of Surgery, UCLA School of Medicine and VAMC, West Los Angeles, CA 90073, USA.

0041-l 345/97/$17.00 PII SOO41-1345(97)00181-4

1961