Abstract：Abstract Exogenous gene stably integrated into the host genome, and stably inherited to the offspring, producing transgenic animals is a basic requirement. Analysis of transgenic animals for inheritance and expression stability of transgene is an important part of establishing a transgenic animal strain. The T cell-activated costimulatory pathway can be blocked by LEA29Y expressed in islet cells of transgenic pig (Sus scrofa), and the T cell-mediated immune rejection in humans after islet transplantation surgery is reduced. A transgenic pig prepared by this research group that specifically expressed LEA29Y in islets, but its inherited genetic condition remains to be determined. In order to obtain islet-specific expression of LEA29Y transgenic pig strain for islet xenograft, the inheritance and expression of two-generation LEA29Y transgenic pigs was continuously traced. 1 male (coded 81 ) and 2 females (coded 77, 83)，a total of 3 LEA29Y founder pigs (F0) were bred each other or bred with wild-type pigs to get F1 generation pigs. Positive individuals in the F1 generation pigs and wild-type pigs were bred to get F2 generation pigs. The transgenic piglet was detected by PCR. The LEA29Y expression of transgenic pig's heart, liver, spleen, lung, kidney, pancreas, muscle, and other tissues were tested by reverse transcription-PCR(RT-PCR). Especially the specific expression of LEA29Y in islet was analyzed by immunohistochemistry and immunofluorescence staining. Three founder pigs coded 77, 81, 83 can all be bred, and a total of 95 progenies were obtained, PCR tested that 53 progenies were positive. RT-PCR results showed that individuals coded 77 and 83 were non-specific expression LEA29Y in 77 and 83 lines. The results of RT-PCR, immunohistochemistry, and immunofluorescence showed that the islet-specific expression of LEA29Y was both in the F0 generation coded 81 and F1 generation coded 271 in 81 lines. And the inheritance of genetic was stable. All above, this study successfully screened for a genetically stable line of LEA29Y transgenic pigs, which can serve as a reliable donor for the study of islet xenotransplantation.
