TABLE 2.
Synergy of human IgG MAbs F105, 2F5, and 2G12 for SHIV-vpu+ neutralizationa in macaque PBMC
| Single antibody (specificity) or combination (ratio) | Concn (μg/ml) for neutralization at:
|
CL90b | DRI at EC90c
|
|||
|---|---|---|---|---|---|---|
| 50% | 90% | MAb A | MAb B | MAb C | ||
| F105 (anti-CD4bd) | 1.9 | NAd | ||||
| 2F5 (anti-gp41) | 0.6 | 2.9 | ||||
| 2G12 (anti-gp120) | 0.5 | 2.5 | ||||
| F105 + 2F5 (2:1) | 1.0 | 4.3 | 0.6 | 7.7 | 2.0 | |
| F105 + 2G12 (2:1) | 0.6 | 3.1 | 0.5 | 10.5 | 2.3 | |
| 2F5 + 2G12 (1:1) | 0.4 | 2.0 | 0.8 | 2.7 | 2.3 | |
| F105 + 2F5 + 2G12 (2:1:1) | 0.4 | 2.1 | 0.5 | 20.3 | 5.3 | 4.5 |
a
The dose for neutralization by combination of two or three antibodies was the sum of that for each antibody used in the combination regimen.
b
Synergy is indicated when the CI is <1.0. CIs were calculated based on the classical isobol equation (8, 10).
c
DRIs were measured by comparing the doses required to reach a given degree of virus neutralization (i.e., 90%) when the antibody was used alone and in combination with other antibodies. Antibodies A, B, and C indicate the antibodies in first, second, and third positions, respectively.
d
NA, not achieved at the highest concentration tested.