Ohzato H, Porter J, Monaco A P, Montana E, Maki T
Division of Organ Transplantation, New England Deaconess Hospital, Boston, MA 02215.
Transplantation. 1993 Aug;56(2):270-4. doi: 10.1097/00007890-199308000-00003.
In streptozocin (SZ)-induced diabetic mice, 200 islets, but not 50 islets, consistently restore euglycemia within 1 week of transplantation. To determine the minimum number of islets sufficient to maintain euglycemia in a diabetic mouse, we first transplanted 50 and 150 syngeneic islets simultaneously into the right (RK) and left kidney (LK), respectively, and then removed the LK 1 week post-transplantation. The remaining 50 islets maintained euglycemia in 8 of 11 mice with normal intravenous glucose tolerance tests (IVGTT). Protection of 50 islets for at least 7 days was necessary because removal of the 150 islets at 5 or 3 days resulted in a much lower incidence of persistent euglycemia. Similarly, 25 islets were capable of maintaining euglycemia in 2 of 9 mice once hyperglycemia was reversed by split-transplantation of 25 (RK) and 175 (LK) islets. To examine if 50-islet allografts survive longer than 200-islet allografts, we split-transplanted 50 DBA/2 islets in the RK and 150 islets of either B6 (syngeneic), DBA/2 (allogeneic), or C3H/He (third party allogeneic) mouse origin in the LK in 3 groups of diabetic C57BL/6 (B6) mice. The survival of 50 DBA/2 islets in each group after removal of the LK on day 7 was compared to that of 200 DBA/2 islets in control B6 mice. Maximum prolongation of allograft survival was obtained with 50 DBA/2 islets that were split-transplanted with syngeneic B6 islets. These results clearly demonstrate that 50 islets are sufficient to maintain normal glucose tolerance once euglycemia is induced by transplantation of a larger number (i.e., 200) of islets and that 50 islet allografts are much less immunogenic than 200-islet allografts.
在链脲佐菌素（SZ）诱导的糖尿病小鼠中，200个胰岛移植后能在1周内持续恢复正常血糖水平，而50个胰岛则不能。为了确定维持糖尿病小鼠正常血糖水平所需的最少胰岛数量，我们首先将50个和150个同基因胰岛分别同时移植到右侧肾脏（RK）和左侧肾脏（LK），然后在移植后1周切除LK。在11只静脉葡萄糖耐量试验（IVGTT）正常的小鼠中，剩余的50个胰岛使8只小鼠维持了正常血糖水平。保护50个胰岛至少7天是必要的，因为在5天或3天切除150个胰岛后，持续正常血糖水平的发生率要低得多。同样，一旦通过分别移植25个（RK）和175个（LK）胰岛逆转高血糖后，25个胰岛能够使9只小鼠中的2只维持正常血糖水平。为了研究50个胰岛的同种异体移植是否比200个胰岛的同种异体移植存活时间更长，我们将3组糖尿病C57BL/6（B6）小鼠的RK分别移植50个DBA/2胰岛，LK分别移植150个来自B6（同基因）、DBA/2（同种异体）或C3H/He（第三方同种异体）小鼠的胰岛。在第7天切除LK后，比较每组中50个DBA/2胰岛的存活情况与对照B6小鼠中200个DBA/2胰岛的存活情况。与同基因B6胰岛一起进行分割移植的50个DBA/2胰岛使同种异体移植存活时间得到了最大程度的延长。这些结果清楚地表明，一旦通过移植大量（即200个）胰岛诱导出正常血糖水平，50个胰岛就足以维持正常的葡萄糖耐量，并且50个胰岛的同种异体移植比200个胰岛的同种异体移植免疫原性要低得多。
