The combination of apoptotic U937 cells and IgG from SLE patients induce production of IFN-αa
| Treatments of U937b | Culture Supplement | |||
|---|---|---|---|---|
| Medium | Normal IgG | SLE-IgG 1 | HSV | |
| None | 5 ± 8c | 4 ± 5 | 53 ± 54 | 3485 ± 955 |
| UV (60 mJ) | 20 ± 18 | 13 ± 6 | 1180 ± 219 | 2035 ± 530 |
| Anti-Fas Ab | 17 ± 19 | 11 ± 7 | 1147 ± 165 | 2740 ± 935 |
| Etoposide | 11 ± 2 | 25 ± 17 | 565 ± 136 | 4060 ± 458 |
a Normal PBMC were cultured in triplicates for 24 h with U937 cells, together with either medium, normal IgG, SLE-IgG, or HSV. Levels of IFN-α in culture supernatants were then determined by immunoassay.
b The U937 cells were treated with UV light, anti-Fas Abs for 1 h, or etoposide for 6 h and then cultured for 24 h from start of apoptotic treatment, before addition of PBMC (see Materials and Methods).
c The figures represent produced IFN-α (U/ml; means ± SD). Representative results from one of three experiments.