Figure 5. TNF-α and IL-10 induction by HBsAg may be responsible for IFN-α inhibition in PBMCs.

(A, B, C) PBMCs at a concentration of 2×10⁶/200 µl were cultured in 96-well culture plates, and 10 ng/ml of exogenous TNF-α (A), IL-10 (B) or TNF-α and IL-10 together (C) was added to the PBMCs for 24 hours followed by stimulation with 3 µM CpG ODN2216 for 24 hours. IFN-α secretion was determined by an ELISA. The data are representative of at least three experiments. (D) PBMCs at a concentration of 2×10⁶/200 µl were cultured in 96-well culture plates, and 10 µg/ml TNF-α and IL-10 neutralization antibodies were added together to the PBMCs with 1 µg/ml HBsAg for 24 hours. The PBMCs were then stimulated with 3 µM CpG ODN2216 for 24 hours. The IFN-α expression level was quantified by an ELISA. Mouse normal IgG₃ was used as a control. The data are representative of at least three experiments.