FIG. 1.

Effect of LL-37, polymyxin B (POL-B), imipenem (IMP), and piperacillin (PIP) on LPS-induced production of TNF-α (Α) and nitric oxide (B). RAW 264.7 cells were stimulated with 100-ng/ml LPS in the absence or presence of the indicated amounts of each drug. TNF-α (Α) and NO (B) were assayed, respectively, in the cell-free medium of cells incubated for 6 and 24 h. The concentrations of TNF-α and NΟ in untreated cells were 61.49 ± 7.58 pg/ml and 6.15 ± 1.87 μM, respectively. Data are presented as the means of at least three experiments ± SD. Statistical analysis was performed according to Student's t test by comparing samples treated with each drug with control cells stimulated with LPS only. A calculated P value of <0.05 (asterisk) was considered significant.