Figure 5.

Effect of 10% FBS and human serum on TNF-α and IL-8 production by PMA-differentiated THP-1 cells in response to OspA, E. coli LPS, Pam₂CSK₄, or Pam₃CSK₄. Cells (2.5 × 10⁵ cells/1 ml per well) were cultured with 10 nM PMA for 48 h and then stimulated by recombinant OspA or purified E. coli LPS, both at 1 μg/ml, or 0.01 μg/ml Pam₂CSK₄ or Pam₃CSK₄ in the presence of 10% heat-inactivated FBS or human serum. After 4 h stimulation, supernatants were collected and their content in TNF-α and IL-8 were analyzed by ELISA. Each value represents the mean ± SD of triplicates from four experiments. **: p < 0.005, ***: p < 0.0001 determined by comparison with 10% FBS using Student's t test.