Table II.

The combination of apoptotic U937 cells and IgG from SLE patients induce production of IFN-αa

Treatments of U937bCulture Supplement
MediumNormal IgGSLE-IgG 1HSV
None5 ± 8c4 ± 553 ± 543485 ± 955
UV (60 mJ)20 ± 1813 ± 61180 ± 2192035 ± 530
Anti-Fas Ab17 ± 1911 ± 71147 ± 1652740 ± 935
Etoposide11 ± 225 ± 17565 ± 1364060 ± 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.