[Establishment of a rat islets model coated with human umbilical vein endothelial cells coexpressing sCD40L-Ig and CTLA4-Ig].

Aim: To isolate and culture primary human umbilical vein endothelial cells (HUVECs) and then to coat rat islets in vitro.

Methods: Primary HUVECs were isolated and cultured, then they were identified by detecting human VIII factor associated antigen with immunohistochemical method. Weible-palade bodies were observed by transmission electron microscope and the phagocytosis for DiI-Ac-LDL was detected by fluorescent microscopy. Rat islets were isolated and coated with HUVECs coexpressing sCD40L-Ig and CTLA4-Ig in a heparinized culture dish. The coated islets were observed via morphology and high glucose challenge test.

Results: The human VIII factor associated antigen, Weible-palade bodies and the phagocytosis for DiI-Ac-LDL were found in HUVECs. The islets coated by HUVECs coexpressing sCD40L-Ig and CTLA4-Ig were identified by green fluorescence proteins. Compared with that of the untreated islets (4.09), the release index of the coated islets was 3.94. There was no difference in insulin release between coated islets and untreated islets under glucose challenge.

Conclusion: HUVECs have been isolated, cultured and identified successfully. The rat islets were coated with HUVECs in vitro function well.