title: Susceptibility of the porcine endogenous retrovirus to reverse transcriptase and protease inhibitors.
abstract: Porcine xenografts may offer a solution to the shortage of human donor allografts. However, all pigs contain the porcine endogenous retrovirus (PERV), raising concerns regarding the transmission of PERV and the possible development of disease in xenotransplant recipients. We evaluated 11 antiretroviral drugs licensed for human immunodeficiency virus type 1 (HIV-1) therapy for their activities against PERV to assess their potential for clinical use. Fifty and 90% inhibitory concentrations (IC(50)s and IC(90)s, respectively) of five nucleoside reverse transcriptase inhibitors (RTIs) were determined enzymatically for PERV and for wild-type (WT) and RTI-resistant HIV-1 reference isolates. In a comparison of IC(50)s, the susceptibilities of PERV RT to lamivudine, stavudine, didanosine, zalcitabine, and zidovudine were reduced >20-fold, 26-fold, 6-fold, 4-fold, and 3-fold, respectively, compared to those of WT HIV-1. PERV was also resistant to nevirapine. Tissue culture-based, single-round infection assays using replication-competent virus confirmed the relative sensitivity of PERV to zidovudine and its resistance to all other RTIs. A Gag polyprotein-processing inhibition assay was developed and used to assess the activities of protease inhibitors against PERV. No inhibition of PERV protease was seen with saquinavir, ritonavir, indinavir, nelfinavir, or amprenavir at concentrations >200-fold the IC(50)s for WT HIV-1. Thus, following screening of many antiretroviral agents, our findings support only the potential clinical use of zidovudine.
authors.affiliation: HIV and Retrovirology Branch, Division of AIDS, STD, and TB Laboratory Research, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
authors.forename: S H
authors.initials: SH
authors.lastname: Qari
authors.forename: S
authors.initials: S
authors.lastname: Magre
authors.forename: J G
authors.initials: JG
authors.lastname: García-Lerma
authors.forename: A I
authors.initials: AI
authors.lastname: Hussain
authors.forename: Y
authors.initials: Y
authors.lastname: Takeuchi
authors.forename: C
authors.initials: C
authors.lastname: Patience
authors.forename: R A
authors.initials: RA
authors.lastname: Weiss
authors.forename: W
authors.initials: W
authors.lastname: Heneine
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D018432:Drug Resistance, Multiple; D020077:Endogenous Retroviruses / Q000187:drug effects* / Q000201:enzymology / Q000502:physiology; D010450:Endopeptidases / Q000378:metabolism; D054303:HIV Reverse Transcriptase / Q000235:genetics; D015497:HIV-1 / Q000187:drug effects / Q000201:enzymology; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D008969:Molecular Sequence Data; D011480:Protease Inhibitors / Q000494:pharmacology*; D012194:RNA-Directed DNA Polymerase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018894:Reverse Transcriptase Inhibitors / Q000494:pharmacology*; D013552:Swine; D014776:Virus Cultivation
chemical_list: D000998:Antiviral Agents; D011480:Protease Inhibitors; D018894:Reverse Transcriptase Inhibitors; D054303:HIV Reverse Transcriptase; D012194:RNA-Directed DNA Polymerase; D010450:Endopeptidases