Characterization of PERV from Bama Miniature Pigs in Human Cells.

Bama miniature pig (BM) as the inbreed pigs is considered to be a potential donor for xenotransplantation. However, porcine endogenous retrovirus (PERV) integrated in pig's genome, is likely to infect human cells in vitro. PERV infection from BM remains unknown. This study aimed to investigate PERV infection in BM in comparison with that of PK15 cells and further to identify the integration sites of PERV from BM (PERV-BM) in human genome. Two full-length PERV-BMs were cloned from 15 isolates of PERV from Bama miniature pigs and sequence analysis indicated that PERV-BM had limited infection to human cells. Subsequently, PBMC from the BM and PK15 cells were co-cultured with HEK293 cells, respectively. Using nested RT-PCR assay and TEM observation, one PERV-BM was observed to infect HEK293 cells with lower transcriptional level than PERV from PK15 cells (PERV-PK) did, while the others showed no sign of transmission of PERV to human cells. Furthermore, 4 and 157 integration sites were identified from PERV-BM-infected HEK293 cells (HEK293-PERV-BM) and PERV-PK- infected HEK293 cells (HEK293-PERV-PK), respectively, which displayed variations of PERV integration. For further verification of the PERV-BM integration, the expression level of cyclin D1, c-myc, p53 and p16 genes of HEK293-PERV-BM decreased significantly while the CDK4 genes were upregulated dramatically in comparison with those of the HEK293-PERV-PK. It is the first time that PERV-BM has been confirmed to be low infection to human cells and highly integration into the PK15 cells. Therefore, BM is a potential xenograft donor due to less PERV transmission to human beings. [ABSTRACT FROM AUTHOR]