Survival of an Islet Allograft Deficient in iNOS after Implantation into Diabetic NOD Mice

Cell Transplantation

Article

Andreas Börjesson¹  Stellan Sandler¹  Annika K. Andersson¹ 

[1] Department of Medical Cell Biology, Uppsala University Uppsala, Sweden;

关键词: Islets;    Cytokines;    iNOS;    NOD mice;   

DOI  :  10.3727/000000006783981495

 received in 2006-03-12, accepted in 2006-06-06,  发布年份 2006

来源: Sage Journals

【 摘 要 】

Proinflammatory cytokines play a major role in rejection of pancreatic islet allografts and in type 1 diabetes (T1D). In rodent islets, exposure to IL-1β alone or combined with IFN-γ induces expression of inducible nitric oxide synthase (iNOS). Inhibition of iNOS or a deletion of the iNOS gene has been shown to be protective in animal models of T1D. In the present study we tested the hypothesis that transplantation of pancreatic islets deficient in iNOS (iNOS–/–) would permit increased graft survival. Pancreatic islets isolated from wild-type (wt) mice and iNOS–/– mice were allogeneically transplanted beneath the kidney capsule of spontaneously diabetic NOD mice. When blood glucose increased above 12.0 mM after preceding normalization of hyperglycemia, animals were sacrificed. Histological examinations of grafts were performed and graft gene expression was analyzed by real-time PCR. Transplantations of the two types of islets could reverse hyperglycemia and the grafts functioned for on average 1 week posttransplantation. Morphological examination of both types of islet grafts showed immune cell infiltration around and within the grafts. Remaining endocrine cells could be observed in wt and iNOS–/– islet grafts. In the removed grafts iNOS-/islet tissue contained higher mRNA levels of insulin, proinsulin convertases (PC-1 and PC-2), and IL-1β compared to transplanted wt islets. The assessments of insulin, PC-1 and PC-2 mRNAs of the grafts suggest that the iNOS–/– islets may be more resistant to destruction in the transplantation model used; however, this was not sufficient to prolong the period of normoglycemia posttransplantation.

【 授权许可】

Unknown   
© 2006 Cognizant Comm. Corp.