Little information is available on the prevalence of drug-resistance mutations in patients harboring the human immunodeficiency virus type 1(HIV-1) circulating recombinant form(CRF)07_BC variant in Sichuan, China. Thi...Little information is available on the prevalence of drug-resistance mutations in patients harboring the human immunodeficiency virus type 1(HIV-1) circulating recombinant form(CRF)07_BC variant in Sichuan, China. This study examined 375 plasma samples from patients with HIV-1 who were infected with the CRF07_BC strain, including 104 drug-naive participants and 271 in whom antiretroviral therapy(ART) had failed. Only one participant in the drug-naive group had a drug-resistance mutation(M46L), compared with 31.73% of those in whom ART had failed. Further analysis showed that 19.56% of strains contained mutations conferring resistance to non-nucleoside reverse transcriptase inhibitors(NNRTIs) alone, 0.74% were resistant to nucleoside reverse transcriptase inhibitors(NRTIs) alone, and 11.44% were dual-resistant to both NRTIs and NNRTIs. The most common mutation in the ART-failure group was M184V(35.88%), K103N(45.01%), Y181C(17.33%), and G190S/A(15.88%). The percentages of HIV-1 strains resistant to lamivudine, emtricitabine, efavirenz, etravirine, and nevirapine were 10.70%, 10.70%, 28.04%, 7.75%, and 26.20%, respectively. To explore site variants possibly related to drug resistance, variations in the ancestor/consensus CRF07_BC sequences from the therapy-naive and ART-failure groups were compared, and seven mutations at six positions were identified as being significantly differently distributed between the two groups(p<0.05). Detailed sequence data will provide information on CRF07_BC genetic characterizations, and improve our understanding of antiretroviral susceptibility and the evolution of drug-resistance mutations. This will be valuable in developing and implementing local public-health approaches for HIV drug-resistance prevention and treatment.展开更多
The CD4 binding site(CD4bs) of envelope glycoprotein(Env) is an important conserved target for anti-human immunodeficiency virus type 1(HIV-1) neutralizing antibodies. Neutralizing monoclonal antibodies IgG1 b12(b12) ...The CD4 binding site(CD4bs) of envelope glycoprotein(Env) is an important conserved target for anti-human immunodeficiency virus type 1(HIV-1) neutralizing antibodies. Neutralizing monoclonal antibodies IgG1 b12(b12) could recognize conformational epitopes that overlap the CD4 bs of Env. Different virus strains, even derived from the same individual, showed distinct neutralization susceptibility to b12. We examined the key amino acid residues affecting b12 neutralization susceptibility using single genome amplification and pseudovirus neutralization assay. Eleven amino acid residues were identified that affect the sensitivity of Env to b12. Through site-directed mutagenesis, an amino acid substitution at position 182 in the V2 region of Env was confirmed to play a key role in regulating the b12 neutralization susceptibility. The introduction of V182 L to a resistant strain enhanced its sensitivity to b12 more than twofold. Correspondingly, the introduction of L182 V to a sensitive strain reduced its sensitivity to b12 more than tenfold. Amino acid substitution at positions 267 and 346 could both enhance the sensitivity to b12 more than twofold. However, no additive effect was observed when the three site mutageneses were introduced into the same strain, and the sensitivity was equivalent to the single V182 L mutation. CRF07_BC is a major circulating recombinant form of HIV-1 prevalent in China. Our data may provide important information for understanding the molecular mechanism regulating the neutralization susceptibility of CRF07_BC viruses to b12 and may be helpful for a vaccine design targeting the CD4 bs epitopes.展开更多
Objective New rationally designed i,i＋7-hydrocarbon-stapled peptides that target both HIV-1 assembly and entry have been shown to have antiviral activity against HIV-1 subtypes circulating in Europe and North America...Objective New rationally designed i,i＋7-hydrocarbon-stapled peptides that target both HIV-1 assembly and entry have been shown to have antiviral activity against HIV-1 subtypes circulating in Europe and North America. Here, we aimed to evaluate the antiviral activity of these peptides against HIV-1 subtypes predominantly circulating in China. Methods The antiviral activity of three i,i＋7-hydrocarbon-stapled peptides, NYAD-36, NYAD-67, and NYAD-66, against primary HIV-1 CRF07_BC and CRFOI_AE isolates was evaluated in peripheral blood mononuclear cells （PI3MCs）. The activity against the CRF07_BC and CRF01_AE Env-pseudotyped viruses was analyzed in TZM-bl cells. Results We found that all the stapled peptides were effective in inhibiting infection by all the primary HIV-1 isolates tested, with 50% inhibitory concentration toward viral replication （ICso） in the low micromolar range. NYAD-36 and NYAD-67 showed better antiviral activity than NYAD-66 did. We further evaluated the sensitivity of CRF01_AE and CRF07_BC Env-pseudotyped viruses to these stapled peptides in a single-cycle virus infectivity assay. As observed with the primary isolates, the ICs0s were in the low micromolar range, and NYAD-66 was less effective than NYAD-36 and NYAD-67. Conclusion Hydrocarbon-stapled peptides appear to have broad antiviral activity against the predominant HIV-1 viruses in China. This finding may provide the impetus to the rational design of peptides for future antiviral therapy.展开更多
基金supported by the Chinese Government AIDS Program (grant number 2008ZX001-016)the China 4th Global Fund AIDS Program (grant number CHN-405-G05-H)a Sichuan Provincial Health Department research project (number 120154)
文摘Little information is available on the prevalence of drug-resistance mutations in patients harboring the human immunodeficiency virus type 1(HIV-1) circulating recombinant form(CRF)07_BC variant in Sichuan, China. This study examined 375 plasma samples from patients with HIV-1 who were infected with the CRF07_BC strain, including 104 drug-naive participants and 271 in whom antiretroviral therapy(ART) had failed. Only one participant in the drug-naive group had a drug-resistance mutation(M46L), compared with 31.73% of those in whom ART had failed. Further analysis showed that 19.56% of strains contained mutations conferring resistance to non-nucleoside reverse transcriptase inhibitors(NNRTIs) alone, 0.74% were resistant to nucleoside reverse transcriptase inhibitors(NRTIs) alone, and 11.44% were dual-resistant to both NRTIs and NNRTIs. The most common mutation in the ART-failure group was M184V(35.88%), K103N(45.01%), Y181C(17.33%), and G190S/A(15.88%). The percentages of HIV-1 strains resistant to lamivudine, emtricitabine, efavirenz, etravirine, and nevirapine were 10.70%, 10.70%, 28.04%, 7.75%, and 26.20%, respectively. To explore site variants possibly related to drug resistance, variations in the ancestor/consensus CRF07_BC sequences from the therapy-naive and ART-failure groups were compared, and seven mutations at six positions were identified as being significantly differently distributed between the two groups(p<0.05). Detailed sequence data will provide information on CRF07_BC genetic characterizations, and improve our understanding of antiretroviral susceptibility and the evolution of drug-resistance mutations. This will be valuable in developing and implementing local public-health approaches for HIV drug-resistance prevention and treatment.
基金supported by grants from National Science and Technology Major Project(2012ZX10004701)
文摘The CD4 binding site(CD4bs) of envelope glycoprotein(Env) is an important conserved target for anti-human immunodeficiency virus type 1(HIV-1) neutralizing antibodies. Neutralizing monoclonal antibodies IgG1 b12(b12) could recognize conformational epitopes that overlap the CD4 bs of Env. Different virus strains, even derived from the same individual, showed distinct neutralization susceptibility to b12. We examined the key amino acid residues affecting b12 neutralization susceptibility using single genome amplification and pseudovirus neutralization assay. Eleven amino acid residues were identified that affect the sensitivity of Env to b12. Through site-directed mutagenesis, an amino acid substitution at position 182 in the V2 region of Env was confirmed to play a key role in regulating the b12 neutralization susceptibility. The introduction of V182 L to a resistant strain enhanced its sensitivity to b12 more than twofold. Correspondingly, the introduction of L182 V to a sensitive strain reduced its sensitivity to b12 more than tenfold. Amino acid substitution at positions 267 and 346 could both enhance the sensitivity to b12 more than twofold. However, no additive effect was observed when the three site mutageneses were introduced into the same strain, and the sensitivity was equivalent to the single V182 L mutation. CRF07_BC is a major circulating recombinant form of HIV-1 prevalent in China. Our data may provide important information for understanding the molecular mechanism regulating the neutralization susceptibility of CRF07_BC viruses to b12 and may be helpful for a vaccine design targeting the CD4 bs epitopes.
基金supported by the National Natural Science Foundation of China(NSFC,No.81261120384)the Key Project of the State Key Laboratory for Infectious Diseases Prevention and Control(SKLID,No.2011SKLID102)+3 种基金the Ministry of Science and Technology of China(2012ZX10001-002)the European Research Infrastructures for Poverty Related Diseases(312661)by funds from NIH Grant RO1 AI104416(AKD)the New York Blood Center(AKD)
文摘Objective New rationally designed i,i＋7-hydrocarbon-stapled peptides that target both HIV-1 assembly and entry have been shown to have antiviral activity against HIV-1 subtypes circulating in Europe and North America. Here, we aimed to evaluate the antiviral activity of these peptides against HIV-1 subtypes predominantly circulating in China. Methods The antiviral activity of three i,i＋7-hydrocarbon-stapled peptides, NYAD-36, NYAD-67, and NYAD-66, against primary HIV-1 CRF07_BC and CRFOI_AE isolates was evaluated in peripheral blood mononuclear cells （PI3MCs）. The activity against the CRF07_BC and CRF01_AE Env-pseudotyped viruses was analyzed in TZM-bl cells. Results We found that all the stapled peptides were effective in inhibiting infection by all the primary HIV-1 isolates tested, with 50% inhibitory concentration toward viral replication （ICso） in the low micromolar range. NYAD-36 and NYAD-67 showed better antiviral activity than NYAD-66 did. We further evaluated the sensitivity of CRF01_AE and CRF07_BC Env-pseudotyped viruses to these stapled peptides in a single-cycle virus infectivity assay. As observed with the primary isolates, the ICs0s were in the low micromolar range, and NYAD-66 was less effective than NYAD-36 and NYAD-67. Conclusion Hydrocarbon-stapled peptides appear to have broad antiviral activity against the predominant HIV-1 viruses in China. This finding may provide the impetus to the rational design of peptides for future antiviral therapy.
