title: Non-cleavage site gag mutations in amprenavir-resistant human immunodeficiency virus type 1 (HIV-1) predispose HIV-1 to rapid acquisition of amprenavir resistance but delay development of resistance to other protease inhibitors.
abstract: In an attempt to determine whether mutations in Gag in human immunodeficiency virus type 1 (HIV-1) variants selected with a protease inhibitor (PI) affect the development of resistance to the same or a different PI(s), we generated multiple infectious HIV-1 clones carrying mutated Gag and/or mutated protease proteins that were identified in amprenavir (APV)-selected HIV-1 variants and examined their virological characteristics. In an HIV-1 preparation selected with APV (33 passages, yielding HIV(APVp33)), we identified six mutations in protease and six apparently critical mutations at cleavage and non-cleavage sites in Gag. An infectious recombinant clone carrying the six protease mutations but no Gag mutations failed to replicate, indicating that the Gag mutations were required for the replication of HIV(APVp33). An infectious recombinant clone that carried wild-type protease and a set of five Gag mutations (rHIV(WTpro)(12/75/219/390/409gag)) replicated comparably to wild-type HIV-1; however, when exposed to APV, rHIV(WTpro)(12/75/219/390/409gag) rapidly acquired APV resistance. In contrast, the five Gag mutations significantly delayed the acquisition of HIV-1 resistance to ritonavir and nelfinavir (NFV). Recombinant HIV-1 clones containing NFV resistance-associated mutations, such as D30N and N88S, had increased susceptibilities to APV, suggesting that antiretroviral regimens including both APV and NFV may bring about favorable antiviral efficacy. The present data suggest that the preexistence of certain Gag mutations related to PI resistance can accelerate the emergence of resistance to the PI and delay the acquisition of HIV resistance to other PIs, and these findings should have clinical relevance in the therapy of HIV-1 infection with PI-including regimens.
authors.affiliation: Department of Hematology, Kumamoto University Graduate School of Medical and Pharmaceutical Sciences, Kumamoto 860-8556, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Aoki
authors.forename: David J
authors.initials: DJ
authors.lastname: Venzon
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Koh
authors.forename: Hiromi
authors.initials: H
authors.lastname: Aoki-Ogata
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Miyakawa
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Yoshimura
authors.forename: Kenji
authors.initials: K
authors.lastname: Maeda
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Mitsuya
mesh_terms: D000595:Amino Acid Sequence; D002219:Carbamates / Q000494:pharmacology*; D002460:Cell Line; D024882:Drug Resistance, Viral; D005663:Furans; D016333:HIV Protease / Q000235:genetics*; D017320:HIV Protease Inhibitors / Q000494:pharmacology*; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics / Q000502:physiology; D006801:Humans; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D020125:Mutation, Missense; D013449:Sulfonamides / Q000494:pharmacology*; D014779:Virus Replication; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000235:genetics*
chemical_list: D002219:Carbamates; D005663:Furans; D017320:HIV Protease Inhibitors; D013449:Sulfonamides; D054301:gag Gene Products, Human Immunodeficiency Virus; C095108:amprenavir; D016333:HIV Protease; C514803:p16 protease, Human immunodeficiency virus 1