Fig. 1.

Poly(I:C) induces the production of TNF-α by LPS-primed human monocytes and THP-1 cells. Human peripheral blood monocytes (Fig. 1A and C) or THP1 cells (Fig. 1B and D) were stimulated with 100 ng/ml LPS (Fig. 1A and B, lane 2) and 100 ng Poly(I:C) (Fig. 1A and B, lane 3) for 16 h. Figure 1(C and D), monocytes or THP1 cells were pre-treated with (Fig. 1C and D, lane 4) or without (Fig. 1C and D, lanes 1–3) LPS for 10 h and then treated with Poly(I:C)(100 ng) for 6 h. The supernatants were collected, and the secreted TNFα was measured by ELISA as described in Methods. These results are representative of three separate experiments. *P < 0.05 compared with control; **P < 0.05 compared with LPS-treated groups.