Genetic and neutralization properties of HIV-1 env clones from subtype B/BC/AE infections in China.
BACKGROUND
As HIV vaccines move into preclinical and clinical trials in China, pseudovirion-based neutralization assays, especially those using env genes of Chinese origin, are widely required to evaluate the ability of HIV vaccines to induce neutralizing antibody (nAb) responses.


METHODS
Functional gp160 genes from plasma samples from Chinese HIV-infected patients were cloned and sequenced and then used to establish a pseudovirus-based neutralization assay. The neutralization phenotypes of the Env-pseudotyped viruses were characterized with known nAbs (4E10, 2F5, IgG1b12, and 2G12) and 43 plasma samples from patients infected with different HIV subtypes.


RESULTS
Overall, 27 functional gp160 genes (18 subtype BC, 3 subtype AE, and 6 subtype B) of HIV-1 were obtained, and their full-length nucleotide sequences were analyzed. The results confirmed the presence of significant genetic diversity among the clones. 4E10 neutralized all 27 Env-pseudotyped viruses, whereas IgG1b12 neutralized 44% of them. 2F5 neutralized 67% and 100% of subtype B and AE clones, respectively, but not subtype BC clones, whereas 2G12 neutralized 33% of subtype B viruses but not subtype BC and AE viruses. There were significant differences in the cross-neutralization activities when the neutralization phenotypes of the 27 Env-pseudotyped viruses were characterized using 43 HIV-positive plasma samples.


CONCLUSIONS
These characterized functional HIV-1 env clones should be useful for standardizing neutralization assays in China.
Chong
Huihui
H
College of Life Science, Jilin University, Changchun, China.
Hong
Kunxue
K
Zhang
Chuntao
C
Nie
Jianhui
J
Song
Aijing
A
Kong
Wei
W
Wang
Youchun
Y
D000911:Antibodies, Monoclonal / Q000276:immunology; D002681:China; D000939:Epitopes / Q000276:immunology; D015752:Genes, env; D015483:HIV Antibodies / Q000276:immunology*; D019302:HIV Envelope Protein gp160 / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D015658:HIV Infections / Q000276:immunology / Q000821:virology*; D015497:HIV-1 / Q000235:genetics* / Q000276:immunology*; D006801:Humans; D009500:Neutralization Tests; D010802:Phylogeny; D012680:Sensitivity and Specificity
D000911:Antibodies, Monoclonal; D000939:Epitopes; D015483:HIV Antibodies; D019302:HIV Envelope Protein gp160