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. 2002 Sep;76(18):9035-45.
doi: 10.1128/jvi.76.18.9035-9045.2002.

Human monoclonal antibodies specific for conformation-sensitive epitopes of V3 neutralize human immunodeficiency virus type 1 primary isolates from various clades

Miroslaw K Gorny  1 , Constance Williams, Barbara Volsky, Kathy Revesz, Sandra Cohen, Victoria R Polonis, William J Honnen, Samuel C Kayman, Chavdar Krachmarov, Abraham Pinter, Susan Zolla-Pazner
Affiliations

Human monoclonal antibodies specific for conformation-sensitive epitopes of V3 neutralize human immunodeficiency virus type 1 primary isolates from various clades

Miroslaw K Gorny et al. J Virol. 2002 Sep.

Abstract

The epitopes of the V3 domain of the human immunodeficiency virus type 1 (HIV-1) gp120 glycoprotein have complex structures consisting of linear and conformational antigenic determinants. Anti-V3 antibodies (Abs) recognize both types of elements, but Abs which preferentially react to the conformational aspect of the epitopes may have more potent neutralizing activity against HIV-1, as recently suggested. To test this hypothesis, human anti-V3 monoclonal Abs (MAbs) were selected using a V3 fusion protein (V3-FP) which retains the conformation of the third variable region. The V3-FP consists of the V3(JR-CSF) sequence inserted into a truncated form of murine leukemia virus gp70. Six human MAbs which recognize epitopes at the crown of the V3 loop were selected with the V3-FP. They were found to react more strongly with molecules displaying conformationally intact V3 than with linear V3 peptides. In a virus capture assay, these MAbs showed cross-clade binding to native, intact virions of clades A, B, C, D, and F. No binding was found to isolates from subtype E. The neutralizing activity of MAbs against primary isolates was determined in three assays: the GHOST cell assay, a phytohemagglutinin-stimulated peripheral blood mononuclear cell assay, and a luciferase assay. While these new MAbs displayed various degrees of activity, the pattern of cross-clade neutralization of clades A, B, and F was most pronounced. The neutralization of clades C and D viruses was weak and sporadic, and neutralization of clade E by these MAbs was not detected. Analysis by linear regression showed a highly significant correlation (P < 0.0001) between the strength of binding of these anti-V3 MAbs to intact virions and the percent neutralization. These studies demonstrate that human MAbs to conformation-sensitive epitopes of V3 display cross-clade reactivity in both binding to native, intact virions and neutralization of primary isolates.

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Figures

FIG. 1.
FIG. 1.
Competition of various MAbs with biotinylated anti-V3 MAb 447-52D for binding to V3-FP. Each of the unlabeled MAbs, diluted from 20.0 to 0.06 μg/ml, was mixed 1:1 with biotinylated 447-52D and then incubated on V3-FP-coated ELISA wells. Binding of biotinylated 447-52D was detected by streptavidin-alkaline phosphatase in ELISA format. The results are shown as percent inhibition of bound biotinylated 447-52D by unlabeled MAbs. The positive control was unlabeled 447-52D; the negative control was anti-parvovirus B19 MAb 1418.
FIG. 2.
FIG. 2.
Effect of disulfide bond reduction and carbohydrate oxidation on binding of MAbs to gp120451. gp120451 was immobilized on an ELISA plate, treated with DTT (•) or with sodium metaperiodate (○) at concentrations from 10 to 0 mM, and then exposed to MAbs at 10 μg/ml. Two MAbs were used as controls: 1331A (anti-C5) (A) recognizes a linear epitope, and its binding is not affected by DTT or NaIO4, while 654 (anti-CD4bd) (B) is conformation dependent, and its binding is abolished upon treatment with either reagent. Anti-V3 MAbs (C to I) displayed various degrees of reduced reactivity with gp120451 treated with DTT or NaIO4. The results from one of three similar experiments are represented. O.D., optical density at 410 nm.
FIG. 3.
FIG. 3.
Pattern of binding of MAbs to native, intact virions representing HIV-1 clades A to F. The binding study was performed using the virus binding assay, in which virions are bound to MAbs that are immobilized on ELISA plates. Bound virus is determined by measuring the level of p24 released when bound virus is lysed with detergent. Each value represents the mean p24 value (in picograms per milliliter) of three experiments. MAb 246 against gp41 was used as a positive control. The irrelevant MAb 1418 against parvovirus B19 served as a negative control, and the binding values of 1418 versus each virus served to establish the cutoff value (shown in parentheses), which was defined as the mean binding with MAb 1418 + 3 standard deviations. The boxes are coded as follows: open, less than the cutoff value; light shading, binding up to 50% of the level of binding achieved with MAb 246; dark shading, >50% of MAb 246 values.
FIG. 4.
FIG. 4.
Analysis by linear regression of neutralization results obtained by two assays, the GHOST cell assay and the PHA blast assay. The 95% confidence interval boundary (dashed lines near the best-fit regression line) and the 95% prediction interval (outer dashed lines) are shown. The latter area is expected to include 95% of all data points. The highly significant correlation indicates similar neutralizing activities of MAbs measured by two different assays.
FIG. 5.
FIG. 5.
Neutralization of pseudotyped viruses SF162(NL4-3luc) (A) and JR-FL(NL4-3luc) (B) by anti-V3 MAbs. The cutoff values, based on the 95% confidence level calculated from data with the irrelevant MAb 1418, were 19 and 8% for SF162 and JR-FL, respectively.
FIG. 6.
FIG. 6.
Correlation between the abilities of MAbs to bind to and to neutralize primary isolates of various HIV-1 clades. (Top) Data for 77 MAb-virus combinations tested in the GHOST cell neutralizing assay and the virus binding assay with seven anti-V3 MAbs and 11 viruses (CA1 and VI191, clade A; MNp, JR-FL, CA5, and Bx08, clade B; 2036 and 93IN904, clade C; 92UG021, clade D; 92TH009, clade E; and 93BR019, clade F). (Bottom) Data for 35 MAb-virus combinations tested in the PHA blast neutralization assay with seven anti-V3 MAbs and five viruses (VI191, clade A; MNp and Bx08, clade B; 2036, clade C; and 93BR029, clade F). The best-fit regression lines and P values from linear regression analyses are shown.
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References

    1. Arendrup, M., A. Sonnerborg, B. Svennerholm, L. Akerblom, C. Nielsen, H. Clausen, S. Olofsson, J. O. Nielsen, and J.-E. S. Hansen. 1993. Neutralizing antibody response during human immunodeficiency virus type 1 infection: type and group specificity and viral escape. J. Gen. Virol. 74:855-863. - PubMed
    1. Beddows, S. A., S. Louisirirotchanakul, R. Cheingsong-Popov, P. J. Easterbrook, P. Simmonds, and J. N. Weber. 1998. Neutralization of primary and T-cell line adapted isolates of the human immunodeficiency virus type 1: role of V3 specific antibodies. J. Gen. Virol. 79:77-82. - PubMed
    1. Bolmstedt, A., S. Olofsson, E. Sjogren-Jansson, S. Jeansson, I. Sjoblom, L. Akerblom, J.-E. S. Hansen, and S.-L. Hu. 1992. Carbohydrate determinant NeuAc-GalB(1-4) of N-linked glycans modulates the antigenic activity of human immunodeficiency virus type 1 glycoprotein gp120. J. Gen. Virol. 73:3099-3105. - PubMed
    1. Bou-Habib, D. C., G. Roderiquez, T. Oravecz, P. W. Berman, P. Lusso, and M. A. Norcross. 1994. Cryptic nature of envelope V3 region epitopes protects primary monocytotropic human immunodeficiency virus type 1 from antibody neutralization. J. Virol. 68:6006-6013. - PMC - PubMed
    1. Cecilia, D., V. N. KewalRamani, J. O'Leary, B. Volsky, P. N. Nyambi, S. Burda, S. Xu, D. R. Littman, and S. Zolla-Pazner. 1998. Neutralization profiles of primary human immunodeficiency virus type 1 isolates in the context of coreceptor usage. J. Virol. 72:6988-6996. - PMC - PubMed

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