Establishment of transgenic mice tissue-specifically expressing human decay accelerating factor on the vascular endothelium / 中华器官移植杂志

ABSTRACT

Objective To construct transgenic mice tissue-specifically expressing human decay accelerating factor (DAF) on the vascular endothelium for xenotransplantation. Methods Transgenic mice expressing hDAF were generated by microinjection of a hDAF-minigene under the control of the human intercellular adhesion molecule-2 (ICAM-2) promoter. PCR analysis and Southern blot analysis of genomic DNA were used to examine the presence of the transgene in the genome of the offspring, and the expression was detected by RT-PCR and flow cytometry respectively. Immunohistochemical assay was performed to detect the distribution of hDAF on the tissues from these transgenic mice. An ex vivo perfusion model was used to compare hearts from these hDAF mice with wild-type hearts.Results After microinjection of gene, 21 of 133 mice born were shown to be transgenic. Human DAF gene was expressed on the surface of leucocytes in 8 of the 21 hDAF-integrated mice. Expression levels of 8 founders ranged from 70 % to 95 % of that on human leucocytes. Human DAF were strongly expressed on the vascular endothelium of heart, kidney and liver, with little or no positive staining observed on non-endothelial cells. These endothelial-specific hDAF hearts displayed prolonged survival compared to wild-type hearts during perfusion with 20 % human plasma and maintained approximately 20 % maximum work. Conclusions The introduced hDAF gene has been specifically expressed on the vascular endothelium of transgenic mice. The hDAF tissue-specifically expressed on vascular endothelium could enhance xenograft survival.