title: Effects of sequence changes in the HIV-1 gp41 fusion peptide on CCR5 inhibitor resistance.
abstract: A rare pathway of HIV-1 resistance to small molecule CCR5 inhibitors such as Vicriviroc (VCV) involves changes solely in the gp41 fusion peptide (FP). Here, we show that the G516V change is critical to VCV resistance in PBMC and TZM-bl cells, although it must be accompanied by either M518V or F519I to have a substantial impact. Modeling VCV inhibition data from the two cell types indicated that G516V allows both double mutants to use VCV-CCR5 complexes for entry. The model further identified F519I as an independent determinant of preference for the unoccupied, high-VCV affinity form of CCR5. From inhibitor-free reversion cultures, we also identified a substitution in the inner domain of gp120, T244A, which appears to counter the resistance phenotype created by the FP substitutions. Examining the interplay of these changes will enhance our understanding of Env complex interactions that influence both HIV-1 entry and resistance to CCR5 inhibitors.
authors.affiliation: Department of Microbiology and Immunology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10065, USA.
authors.forename: Cleo G
authors.initials: CG
authors.lastname: Anastassopoulou
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Ketas
authors.forename: Rogier W
authors.initials: RW
authors.lastname: Sanders
authors.forename: Per Johan
authors.initials: PJ
authors.lastname: Klasse
authors.forename: John P
authors.initials: JP
authors.lastname: Moore
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D019380:Anti-HIV Agents / Q000494:pharmacology*; D065100:CCR5 Receptor Antagonists; D002460:Cell Line; D024882:Drug Resistance, Viral; D015700:HIV Envelope Protein gp41 / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D015658:HIV Infections / Q000188:drug therapy / Q000378:metabolism / Q000821:virology*; D015497:HIV-1 / Q000737:chemistry / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D020125:Mutation, Missense / Q000187:drug effects; D010879:Piperazines / Q000494:pharmacology; D011743:Pyrimidines / Q000494:pharmacology; D019713:Receptors, CCR5 / Q000378:metabolism; D016415:Sequence Alignment
chemical_list: D019380:Anti-HIV Agents; D065100:CCR5 Receptor Antagonists; D015700:HIV Envelope Protein gp41; D010879:Piperazines; D011743:Pyrimidines; D019713:Receptors, CCR5; C486781:vicriviroc