TY - JOUR
T1 - Polymorphisms of HIV-2 integrase and selection of resistance to raltegravir
AU - Bercoff, Danielle P.
AU - Triqueneaux, Perrine
AU - Lambert, Christine
AU - Oumar, Aboubacar A.
AU - Ternes, Anne Marie
AU - Dao, Sounkalo
AU - Goubau, Patrick
AU - Schmit, Jean Claude
AU - Ruelle, Jean
N1 - Funding Information:
The authors would like to thank Professor Flabou Bougoudogo, Doctors Sekou Traore, Souleymane Diallo, Younoussa Sidibé, Drissa Katilé and Lassane Samaké who made sample collection in Mali possible (Bamako, Segou and Sikasso). They are also grateful to Daniel Struck for his contribution to phylogenetic analyses and valuable discussions. The authors thank all the Belgian ARL (AIDS reference laboratories) collaborators who made sample collection possible. CL is supported by the Fondation Recherche sur le SIDA. AAO is supported by a scholarship from the Coopération Technique Belge from the Université Catholique de Louvain in Brussels, Belgium.
PY - 2010/11/29
Y1 - 2010/11/29
N2 - Background: Human Immunodeficiency Virus type 2 is naturally resistant to some antiretroviral drugs, restricting therapeutic options for patients infected with HIV-2. Regimens including integrase inhibitors (INI) seem to be effective, but little data on HIV-2 integrase (IN) polymorphisms and resistance pathways are available.Materials and methods: The integrase coding sequence from 45 HIV-2-infected, INI-naïve, patients was sequenced and aligned against the ROD (group A) or EHO (group B) reference strains and polymorphic or conserved positions were analyzed.To select for raltegravir (RAL)-resistant variants in vitro, the ROD strain was cultured under increasing sub-optimal RAL concentrations for successive rounds. The phenotype of the selected variants was assessed using an MTT assay.Results: We describe integrase gene polymorphisms in HIV-2 clinical isolates from 45 patients. Sixty-seven percent of the integrase residues were conserved. The HHCC Zinc coordination motif, the catalytic triad DDE motif, and AA involved in IN-DNA binding and correct positioning were highly conserved and unchanged with respect to HIV-1 whereas the connecting residues of the N-terminal domain, the dimer interface and C-terminal LEDGF binding domain were highly conserved but differed from HIV-1. The N155 H INI resistance-associated mutation (RAM) was detected in the virus population from one ARV-treated, INI-naïve patient, and the 72I and 201I polymorphisms were detected in samples from 36 and 38 patients respectively. No other known INI RAM was detected.Under RAL selective pressure in vitro, a ROD variant carrying the Q91R+I175M mutations was selected. The Q91R and I175M mutations emerged simultaneously and conferred phenotypic resistance (13-fold increase in IC50). The Q91R+I175M combination was absent from all clinical isolates. Three-dimensional modeling indicated that residue 91 lies on the enzyme surface, at the entry of a pocket containing the DDE catalytic triad and that adding a positive charge (Gln to Arg) might compromise IN-RAL affinity.Conclusions: HIV-2 polymorphisms from 45 INI-naïve patients are described. Conserved regions as well as frequencies of HIV-2 IN polymorphisms were comparable to HIV-1. Two new mutations (Q91R and I175M) that conferred high resistance to RAL were selected in vitro, which might affect therapeutic outcome.
AB - Background: Human Immunodeficiency Virus type 2 is naturally resistant to some antiretroviral drugs, restricting therapeutic options for patients infected with HIV-2. Regimens including integrase inhibitors (INI) seem to be effective, but little data on HIV-2 integrase (IN) polymorphisms and resistance pathways are available.Materials and methods: The integrase coding sequence from 45 HIV-2-infected, INI-naïve, patients was sequenced and aligned against the ROD (group A) or EHO (group B) reference strains and polymorphic or conserved positions were analyzed.To select for raltegravir (RAL)-resistant variants in vitro, the ROD strain was cultured under increasing sub-optimal RAL concentrations for successive rounds. The phenotype of the selected variants was assessed using an MTT assay.Results: We describe integrase gene polymorphisms in HIV-2 clinical isolates from 45 patients. Sixty-seven percent of the integrase residues were conserved. The HHCC Zinc coordination motif, the catalytic triad DDE motif, and AA involved in IN-DNA binding and correct positioning were highly conserved and unchanged with respect to HIV-1 whereas the connecting residues of the N-terminal domain, the dimer interface and C-terminal LEDGF binding domain were highly conserved but differed from HIV-1. The N155 H INI resistance-associated mutation (RAM) was detected in the virus population from one ARV-treated, INI-naïve patient, and the 72I and 201I polymorphisms were detected in samples from 36 and 38 patients respectively. No other known INI RAM was detected.Under RAL selective pressure in vitro, a ROD variant carrying the Q91R+I175M mutations was selected. The Q91R and I175M mutations emerged simultaneously and conferred phenotypic resistance (13-fold increase in IC50). The Q91R+I175M combination was absent from all clinical isolates. Three-dimensional modeling indicated that residue 91 lies on the enzyme surface, at the entry of a pocket containing the DDE catalytic triad and that adding a positive charge (Gln to Arg) might compromise IN-RAL affinity.Conclusions: HIV-2 polymorphisms from 45 INI-naïve patients are described. Conserved regions as well as frequencies of HIV-2 IN polymorphisms were comparable to HIV-1. Two new mutations (Q91R and I175M) that conferred high resistance to RAL were selected in vitro, which might affect therapeutic outcome.
UR - http://www.scopus.com/inward/record.url?scp=78650845158&partnerID=8YFLogxK
U2 - 10.1186/1742-4690-7-98
DO - 10.1186/1742-4690-7-98
M3 - Article
C2 - 21114823
AN - SCOPUS:78650845158
SN - 1742-4690
VL - 7
JO - Retrovirology
JF - Retrovirology
M1 - 98
ER -