Porcine endogenous retrovirus transmission characteristics of an inbred herd of miniature swine.
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ABSTRACT:
SUBMITTER: Oldmixon BA
PROVIDER: S-EPMC135987 | biostudies-literature | 2002 Mar
REPOSITORIES: biostudies-literature
Publications
Porcine endogenous retrovirus transmission characteristics of an inbred herd of miniature swine.
Oldmixon Beth A BA Wood James C JC Ericsson Thomas A TA Wilson Carolyn A CA White-Scharf Mary E ME Andersson Goran G Greenstein Julia L JL Schuurman Henk-Jan HJ Patience Clive C
Journal of virology 20020301 6
Here we report the identification of inbred miniature swine that failed to produce human-tropic replication-competent porcine endogenous retroviruses (HTRC PERVs), using in vitro coculture assays. When HTRC PERVs were isolated from transmitting animals, all were recombinant viruses, with the receptor-binding domain of PERV-A combining with PERV-C-related sequences. ...[more]
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Project description:Porcine endogenous retrovirus (PERV) is a potential pathogen in clinical xenotransplantation; transmission of PERV in vivo has been suggested in murine xenotransplantation models. We analyzed the transmission of PERV to human cells in vivo using a model in which immunodeficient NOD/SCID transgenic mice were transplanted with porcine and human lymphohematopoietic tissues. Our results demonstrate, we believe for the first time, that human and pig cells can coexist long-term (up to 25 weeks) without direct PERV infection of human cells. Despite the transplantation of porcine cells that did not produce human-tropic PERV, human cells from the chimeric mice were frequently found to contain PERV sequences. However, this transmission was due to the pseudotyping of PERV-C (a virus without human tropism) by xenotropic murine leukemia virus, rather than to de novo generation of human-tropic PERV. Thus, pseudotyping might account for the PERV transmission previously observed in mice. The absence of direct human cell infection following long-term in vivo coexistence with large numbers of porcine cells provides encouragement regarding the potential safety of using pigs that do not produce human-tropic PERV as source animals for transplantation to humans.
| S-EPMC514590 | biostudies-literature
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