Please use this identifier to cite or link to this item: https://hdl.handle.net/1959.11/20610
Title: A common mechanism of clinical HIV-1 resistance to the CCR5 antagonist maraviroc despite divergent resistance levels and lack of common gp120 resistance mutations
Contributor(s): Roche, Michael (author); Salimi, Hamid (author); Ellett, Anne (author); Gray, Lachlan R (author); Lee, Benhur (author); Jubb, Becky (author); Westby, Mike (author); Ramsland, Paul A (author); Lewin, Sharon R (author); Payne, Richard J (author); Churchill, Melissa J (author); Gorry, Paul R (author); Duncan, Renee (author); Wilkinson, Brendan  (author)orcid ; Chikere, Kelechi (author); Moore, Miranda S (author); Webb, Nicholas E (author); Zappi, Helena (author); Sterjovski, Jasminka (author); Flynn, Jacqueline K (author)
Publication Date: 2013
Open Access: Yes
DOI: 10.1186/1742-4690-10-43Open Access Link
Handle Link: https://hdl.handle.net/1959.11/20610
Abstract: Background. The CCR5 antagonist maraviroc (MVC) inhibits human immunodeficiency virus type 1 (HIV-1) entry by altering the CCR5 extracellular loops (ECL), such that the gp120 envelope glycoproteins (Env) no longer recognize CCR5. The mechanisms of HIV-1 resistance to MVC, the only CCR5 antagonist licensed for clinical use are poorly understood, with insights into MVC resistance almost exclusively limited to knowledge obtained from 'in vitro' studies or from studies of resistance to other CCR5 antagonists. To more precisely understand mechanisms of resistance to MVC 'in vivo', we characterized Envs isolated from 2 subjects who experienced virologic failure on MVC. Results. Envs were cloned from subjects 17 and 24 before commencement of MVC (17-Sens and 24-Sens) and after virologic failure (17-Res and 24-Res). The Envs cloned during virologic failure showed broad divergence in resistance levels, with 17-Res Env exhibiting a relatively high maximal percent inhibition (MPI) of ~90% in NP2-CD4/CCR5 cells and peripheral blood mononuclear cells (PBMC), and 24-Res Env exhibiting a very low MPI of ~0 to 12% in both cell types, indicating relatively "weak" and "strong" resistance, respectively. Resistance mutations were strain-specific and mapped to the gp120 V3 loop. Affinity profiling by the 293-Affinofile assay and mathematical modeling using VERSA (Viral Entry Receptor Sensitivity Analysis) metrics revealed that 17-Res and 24-Res Envs engaged MVC-bound CCR5 inefficiently or very efficiently, respectively. Despite highly divergent phenotypes, and a lack of common gp120 resistance mutations, both resistant Envs exhibited an almost superimposable pattern of dramatically increased reliance on sulfated tyrosine residues in the CCR5 N-terminus, and on histidine residues in the CCR5 ECLs. This altered mechanism of CCR5 engagement rendered both the resistant Envs susceptible to neutralization by a sulfated peptide fragment of the CCR5 N-terminus. Conclusions. Clinical resistance to MVC may involve divergent Env phenotypes and different genetic alterations in gp120, but the molecular mechanism of resistance of the Envs studied here appears to be related. The increased reliance on sulfated CCR5 N-terminus residues suggests a new avenue to block HIV-1 entry by CCR5 N-terminus sulfopeptidomimetic drugs.
Publication Type: Journal Article
Source of Publication: Retrovirology, v.10, p. 1-20
Publisher: BioMed Central Ltd
Place of Publication: United Kingdom
ISSN: 1742-4690
Field of Research (FOR): 060502 Infectious Agents
060506 Virology
060503 Microbial Genetics
Socio-Economic Outcome Codes: 920109 Infectious Diseases
970106 Expanding Knowledge in the Biological Sciences
Peer Reviewed: Yes
HERDC Category Description: C1 Refereed Article in a Scholarly Journal
Statistics to Oct 2018: Visitors: 80
Views: 118
Downloads: 2
Appears in Collections:Journal Article

Files in This Item:
2 files
File Description SizeFormat 
Show full item record

SCOPUSTM   
Citations

43
checked on Nov 30, 2018

Page view(s)

50
checked on Feb 7, 2019
Google Media

Google ScholarTM

Check

Altmetric


Items in Research UNE are protected by copyright, with all rights reserved, unless otherwise indicated.