Article

Organogenesis of pancreatic anlagen allografted in rats.

Institute of Organ Transplantation, Key Laboratory of Organ Transplantation (HUST), Ministry of Education, Key Laboratory of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Transplantation Proceedings (Impact Factor: 0.95). 01/2007; 38(10):3280-2. DOI: 10.1016/j.transproceed.2006.10.120
Source: PubMed

ABSTRACT To study the possibility of revascularization, growth, and differentiation of embryonic pancreatic anlagen transplanted to adult hosts. While transplantations of pancreas and islets are the main methods to cure diabetes mellitus, the donor source is in shortage. So it's necessary to find a new source for transplantation.
The pancreas from embryonic day 14.5 (E14.5) and 15.5 (E15.5) Lewis rat embryos were implanted into either intraperitoneal or subrenal capsular site of healthy Lewis rats. at 3 weeks or 6 weeks after implantation, the pancreatic anlagen in the host rats were resected for size measurements, as well as histopathologic and immunohistochemical examinations.
Three weeks after implantation into the renal-capsular site, the size of both E14.5 and E15.5 pancreatic anlagen had enlarged 10- to 15-fold with differentiation of acinar components upon histological examination. Moreover, increasing numbers of beta cells and islets stained positive for insulin, and newly generated vessels were observed around the tissues. Continued proliferation of the endocrine islets in E14.5 pancreatic anlagen grafts was observed after another 3 weeks, whereas further proliferation in the E15.5 pancreatic anlagen graft was not seen. Additionally fibrosis appeared in the exocrine component of both E14.5 and E15.5 pancreatic anlagen at this time point. When implanted into intraperitoneal site, enlarged E15.5 pancreatic anlagen with proliferatels beta cells were also observed after 3 weeks. However, both the size of the pancreatic anlagen and the proliferation of the beta cells were much less than that in the subrenal capsular site.
The allografted E14.5 and E15.5 pancreatic anlagen revascularised and grew into tissues that were structurally similar to normal mature rats pancreatic tissue. Adequate embryonic age for the transplantation of pancreatic anlagen is 14.5 and 15.5 days old. Subrenal capsula is a more suitable site than the peritoneal cavity for implantation of pancreatic anlagen.

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Additional research will be required to develop an effective and safe method for prevention of allograft rejection in the minipig prior to application to diabetic humans.El uso del pncreas fetal como rgano donante en el tratamiento de la diabetes ha sido explorado en la rata y actualmente est siendo ensayado en cerdos. El crecimiento y desarrollo del pncreas fetal colocado bajo la cpsula del rin de una rata diabtica son suficientes para revertir en forma completa la diabetes inducida por estreptozotocina; el rgano as transplantado exhibe un 20–25% del contenido de insulina de un pncreas adulto normal. El pncreas fetal se desarrolla al mximo en un ambiente normoglicmico. La criopreservacin resulta en supervivencia casi completa del pncreas y representa ganancia de tiempo para la tipificacin tisular y sangunea y para realizar pruebas de compatibilidad de los linfocitos donantes y recipientes mediante la Reaccin de Linfocitos Mixtos. 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