Table 2. Inhibitory activity of anti-gp41 antibodies (IgG1s and Fabs) against a panel of HIV-1 primary isolates from different clades measured by the PBMC-RT assay.
The PBMC-RT assay is based on inhibition of spreading infections of PBMCs by primary isolates and measurement of reverse transcriptase (RT) seven days post infection. The percentage inhibition of RT activity (mean ± standard error) in the culture supernatant of HIV-1-infected PBMCs at day seven is presented as a measure of the antibody inhibitory activity (see Materials and Methods for details). The medians for all isolates were calculated by using all triplicate values and not directly from the means for each isolate. The antibody concentration was 50 μg/ml.
| HIV-1 isolate | clade | IgG1 m48 | IgG1 4E10 | Fab m48 | Fab Z13 |
|---|---|---|---|---|---|
| 92UG029 | A | 20±14 | 0+14 | 43+11 | 1.0+17 |
| 92HT594 | B | 65±21 | 31+8.6 | 100+0.1 | 55+23 |
| SHIV 89.6p | B | 83±12 | 25+13 | 97+1.0 | 96+1.2 |
| 92BR025 | C | 68+1.6 | 58+3.2 | 43+16 | 63+3.1 |
| 97ZA003 | C | 94±1.3 | 49+12 | 72+7.7 | 75+7.9 |
| 93IN101 | C | 99±0.1 | 99+0.1 | 100+0.1 | 99+0.1 |
| 93MW959 | C | 97±0.6 | 53+10 | 100+0.0 | 92+1.5 |
| 92UG001 | D | 38±6.4 | 29+0.7 | 99+0.2 | 49+10 |
| 93TH073 | E | 96±0.1 | 68+2.6 | 99+0.0 | 93+1.1 |
| 93BR029 | F | 76±16 | 62+12 | 94+3.3 | 83+11 |
| G3 | G | 93±0.6 | 57+16 | 92+0.4 | 85+3.6 |
| BCF03 | O | 44±16 | 34+7.5 | 99+0.6 | 42+21 |
|
| |||||
| Median | 87 | 51 | 98 | 79 | |