Differential sensitivity of porcine endogenous retrovirus to APOBEC3-mediated inhibition

Arch Virol. 2015 Aug;160(8):1901-8. doi: 10.1007/s00705-015-2450-y. Epub 2015 May 29.

Abstract

Pigs are considered to be suitable xenotransplantation organ donors. However, the risk of pathogen transmission from pigs to humans is a major concern in the transplantation of porcine tissues. The porcine endogenous retroviruses (PERVs) PERV-A, PERV-A/C, and PERV-B can infect human cells, but PERV-C is an ecotropic virus infecting only pig cells. Thus, several strategies have been proposed to reduce PERV transmission in xenograft recipients. Human APOBEC3G (huA3G) is a single-strand DNA cytosine deaminase, which inactivates the coding capacity of the virus by deamination of cDNA cytosines to uracils. This reaction occurs within the (-) DNA strand during reverse transcription, resulting in a G-to-A mutation in the (+) strand. While recent data have shown that PERV-B is severely inhibited by huA3G and porcine A3Z2-Z3 (poA3F) in a pseudotype assay, little is known about PERV-C. Here, we compare the antiretroviral activities of huA3G, huA3F and poA3Z2-Z3 against PERV-C. Our data show that APOBEC3 was packaged into PERV-C particles and inhibited PERV-C replication in a dose-dependent manner. PERV-C infectivity was strongly inhibited by poA3Z2-Z3, but it did not markedly reduce PERV-B infectivity. This suggests that PERV-C Gag interacts efficiently with poA3Z2-Z3. In addition, we constructed stably huA3G- and poA3Z2-Z3-expressing 293-PERV-PK-CIRCE cells (human 293 cells infected with PK15-derived PERVs) to examine whether PERV is resistant to poA3Z2-Z3 in a virus-spreading assay. The stably expressed huA3G and poA3Z2-Z3 were more packaging-competent than transiently expressed APOBEC3 proteins. These results suggest that poA3Z2-Z3 can inhibit PERV replication in a pseudotype assay as well as in a virus-spreading assay.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • APOBEC-3G Deaminase
  • Animals
  • Cytidine Deaminase / genetics
  • Cytidine Deaminase / immunology*
  • Cytosine Deaminase / genetics
  • Cytosine Deaminase / immunology*
  • Endogenous Retroviruses / classification
  • Endogenous Retroviruses / genetics
  • Endogenous Retroviruses / immunology*
  • Endogenous Retroviruses / physiology
  • Host-Pathogen Interactions
  • Humans
  • Retroviridae / classification
  • Retroviridae / genetics
  • Retroviridae / immunology*
  • Retroviridae / physiology
  • Retroviridae Infections / enzymology*
  • Retroviridae Infections / genetics
  • Retroviridae Infections / immunology
  • Retroviridae Infections / virology
  • Swine / genetics
  • Swine / immunology*
  • Swine / virology
  • Transplantation, Heterologous
  • Zoonoses / enzymology*
  • Zoonoses / genetics
  • Zoonoses / immunology
  • Zoonoses / virology

Substances

  • APOBEC3F protein, human
  • Cytosine Deaminase
  • APOBEC-3G Deaminase
  • APOBEC3G protein, human
  • Cytidine Deaminase