IL-6– and IFN-γ–induced increase in the fusion of macrophages with T-tropic envelope-expressing cells is CXCR4 dependent
| Experiment . | Cytokine* . | Inhibitor† . | No. of syncytia with IIIB envelope‡ . |
|---|---|---|---|
| 1 | None | None | 5 ± 1 |
| IFN-γ | None | 40 ± 6 | |
| IFN-γ | SDF-1α | 5 ± 4 | |
| IFN-γ | RANTES | 45 ± 8 | |
| 2 | None | None | 17 ± 1 |
| IFN-γ | None | 60 ± 6 | |
| IFN-γ | SDF-1α | 4 ± 2 | |
| IFN-γ | T22 | 0 | |
| IFN-γ | RANTES | 72 ± 9 | |
| 3 | None | None | 6 ± 1 |
| IL-6 | None | 75 ± 20 | |
| IL-6 | SDF-1α | 0 | |
| IL-6 | RANTES | 87 ± 4 | |
| 4 | None | None | 1 ± 1 |
| IL-6 | None | 57 ± 12 | |
| IL-6 | SDF-1α | 3 ± 1 | |
| IL-6 | T22 | 0 | |
| IL-6 | RANTES | 49 ± 4 |
| Experiment . | Cytokine* . | Inhibitor† . | No. of syncytia with IIIB envelope‡ . |
|---|---|---|---|
| 1 | None | None | 5 ± 1 |
| IFN-γ | None | 40 ± 6 | |
| IFN-γ | SDF-1α | 5 ± 4 | |
| IFN-γ | RANTES | 45 ± 8 | |
| 2 | None | None | 17 ± 1 |
| IFN-γ | None | 60 ± 6 | |
| IFN-γ | SDF-1α | 4 ± 2 | |
| IFN-γ | T22 | 0 | |
| IFN-γ | RANTES | 72 ± 9 | |
| 3 | None | None | 6 ± 1 |
| IL-6 | None | 75 ± 20 | |
| IL-6 | SDF-1α | 0 | |
| IL-6 | RANTES | 87 ± 4 | |
| 4 | None | None | 1 ± 1 |
| IL-6 | None | 57 ± 12 | |
| IL-6 | SDF-1α | 3 ± 1 | |
| IL-6 | T22 | 0 | |
| IL-6 | RANTES | 49 ± 4 |
IL-6 indicates interleukin 6; IFN-γ, interferon γ.
Cytokines were added for the last 24 hours IFN-γ at 200 U/mL) or for the last 48 hr IL-6 at 20 ng/mL) of the 6-day monocyte-derived macrophage (MDM) culture.
Chemokines (1 μg/mL) or T22 peptide (2 μmol) were added to MDMs 1 hour prior to addition of Env-expressing cells.
Mean syncytia counts are shown for duplicate cultures.