TABLE 2.
Neutralization of HIV-1 isolates on MT2 cells following passage in PBMC and T-cell lines
| MAbs, sCD4, and sera | Neutralizing antibody titer of indicated isolate toa:
|
|||||||
|---|---|---|---|---|---|---|---|---|
| M2424/4
|
W61D
|
|||||||
| PBMC(p0)
|
H9(p1)
|
H9(p3)
|
H9(p9)
|
PBMC(p3)
|
PBMC(p5)
|
PBMC
|
SupT1
|
|
| R5X4 | ND | ND | R5X4 | ND | R5X4 | R5X4 | R5X4 | |
| MAbs and sCD4 | ||||||||
| 2F5 | 100 | >100 | 100 | 25 | 12.5 | 25 | >50 | 3.125 |
| 2G12 | >100 | 50 | 25 | 12.5 | 100 | 50 | 12.5 | 6.25 |
| 447-52D | 50 | 25 | 3.125 | 1.56 | 3.125 | 6.25 | >25 | 0.195 |
| sCD4 | 10 | 5 | 1.25 | 0.625 | 1.25 | 5 | ND | ND |
| IgG1b12 | ND | ND | ND | ND | ND | ND | >50 | 6.25 |
| HIV-1 positive sera | ||||||||
| 052 | 160 | 160 | 160 | 160 | 80 | 160 | 320 | 320 |
| 134 | 20 | 40 | 80 | 160 | 80 | 80 | ND | ND |
| FDA#2 | 20 | 20 | 40 | 80 | 40 | 40 | 10 | 320 |
| Vaccinee sera | ||||||||
| F55134 | — | — | 10 | 40 | — | — | — | 80 |
| F53860 | — | — | 10 | 10 | — | — | — | 40 |
| F53863 | — | — | — | 10 | — | — | — | 80 |
| M54662 | — | — | 10 | 20 | — | — | — | 80 |
| F53866 | — | — | 10 | 20 | — | — | — | 80 |
PBMC(p0) represents the primary HIV-1 isolate of M2424/4; H9(p1), H9(p3), and H9(p9) are the viral stocks obtained following the stated number of passages in H9 cells; PBMC(p3) and PBMC(p5) are virus stocks obtained following three or five passages of the H9(p9) stock in PBMC. The W61D virus stocks were obtained from PBMC or following multiple passages in SupT1 cells. Neutralization titers are shown as the reciprocal of the highest dilution of sera or the lowest concentration of MAb or sCD4 to inhibit the formation of syncytia in MT2 cells by 90%, and where no neutralization was observed with the highest concentration of MAb used, this is shown by >. R5X4 represents the ability to replicate in both U87-CD4-CCR5 and U87-CD4-CXCR4 cells. ND, Not done. —, neutralizing titer of <10.