Table 1. Correlation between antibody neutralization and binding to progressively more receptor-triggered forms of the same HIV-1 Env.
| sCD4 [μM] | Env | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| MN.3 | BaL.01 | JR-FL | BG505_T332N | ||||||||||
| r | P | r | P | r | P | r | P | ||||||
| Pearson correlation | 80 | 0.5364 | 0.0264 | * | −0.1271 | 0.627 | ns | −0.08889 | 0.7344 | ns | 0.4389 | 0.078 | ns |
| 20 | 0.5236 | 0.031 | * | −0.00437 | 0.9867 | ns | 0.04003 | 0.8788 | ns | 0.6627 | 0.0037 | ** | |
| 5 | 0.5365 | 0.0264 | * | 0.09431 | 0.7188 | ns | 0.248 | 0.3373 | ns | 0.7374 | 0.0007 | *** | |
| 1.25 | 0.5249 | 0.0305 | * | 0.2269 | 0.3811 | ns | 0.5837 | 0.0139 | * | 0.7524 | 0.0005 | *** | |
| 0.3125 | 0.5619 | 0.0189 | * | 0.4478 | 0.0715 | ns | 0.7892 | 0.0002 | *** | 0.745 | 0.0006 | *** | |
| 0.078125 | 0.4939 | 0.0439 | * | 0.6129 | 0.0089 | ** | 0.8114 | <0.0001 | **** | 0.7576 | 0.0004 | *** | |
| 0 | 0.505 | 0.0387 | * | 0.5987 | 0.0111 | * | 0.8398 | <0.0001 | **** | 0.7722 | 0.0003 | *** | |
Correlation between MFI of antibody binding to the cell surface–expressed CD4-unbound as well as progressively more CD4-bound MN.3, BaL.01, JR-FL, and BG505_T332N Env and AUC for neutralization of the corresponding pseudovirus. CD4bs-directed inhibitors were excluded from the analysis, as their apparent affinity toward Env in the on-cell sCD4 triggering assay is influenced by direct competition for binding with sCD4. Pearson’s r coefficients and respective two-tailed P values are listed. High correlation/low P values are shaded in purple; low correlation/high P values are shaded in yellow.
Abbreviations: AUC, area under the inhibition curve; BG505_T332N, BG505.W6M.ENV.C2_T332N; CD4bs, CD4 binding site; Env, envelope glycoprotein; MFI, mean of fluorescence intensity; ns, not significant; sCD4, soluble CD4.
* P < 0.05.
** P < 0.01.
*** P < 0.001.
**** P < 0.0001.