Fig. 4.

Lipoplex-induced TNF-α secretion is solely dependent on TLR2. Primed THP1 cells were incubated for 1 h in serum-free medium, then 1 h with or without (noAb) 40 μg/mL (20 μg/mL final concentration after addition of stimulants) antibodies blocking TLR2 (AbTLR2) or TLR4 (AbTLR4). Then cells were incubated for 5 h with serum free medium alone (Ctrl) or with RPR 120535, 120525 and 128506 made lipoplexes (20 μM, serum free medium) or LPS (100 ng/mL, complete medium) or Pam₃CSK₄ (30 ng/mL, complete medium). The supernatant was collected and TNF-α quantified by ELISA. Data are expressed as percent of secretion as compared to condition without antibodies (no anti) for each stimulant after subtraction of control. Each bar represents the mean + standard deviation of three replicate values (n = 3). The experiment is representative of at least 3 independent replicates.