Prolonged survival of discordant porcine islet xenografts

Abstract: Purified porcine islets were prepared by collagenase digestion and density gradient purification, and transplanted under the kidney capsule of C57B/B6 mice with streptozotocin-induced diabetes which were receiving varying temporary immunosuppressive therapies. Islets that had been cultured for 1 day at 37 degrees C were rejected after: 9 +/- 0.1 (mean +/- SE) days in control mice; 14 +/- 3 days in mice receiving mouse antilymphocyte serum (MLS) plus porcine antilymphocyte serum (PLS) on day of transplant (day 0); 43 +/- 8 days in mice treated for 1 week with anti-CD4 antibody (aCD4); 36 +/- 4 days in mice given aCD4 for 1 week plus PLS on days 0 and 7; 47 +/- 3 days in mice treated with aCD4 for 1 week plus MLS and PLS on day 21. Porcine islet survival in these latter three groups was significantly (P