FIG. 2.
B. burgdorferi and its lipoproteins induce pro- and anti-inflammatory cytokines in THP-1 monocytoid cells. Vitamin D3-treated THP-1 cells (106/ml) were incubated for 24 h with supplemented medium (RPMI), various concentrations of heat-killed strain JD1 spirochetes (from left to right, 107 to 102 spirochetes/ml, in multiples of 10), or various concentrations of L-OspA, U-OspA, U-OspC (from left to right, 1,000, 500, 250, 100, 10, and 1 ng/ml) and LPS (100, 10, and 1 ng/ml) in the presence or absence of polymyxin B (PB). IL-10 (A) and IL-6 (B) in the cell supernatants were quantified by antibody capture ELISA. Data are representative of two separate experiments. The lower limit of detection of the ELISA was 15 pg/ml.