Objective To evaluate the effect of amphotericin B on the production of tumor necrosis factor-α (TNF-α) and interleukin-8 (IL-8) and activation of p38 mitogen-activated protein kinases (p38MAPK) in a human acute monocytic leukemia cell line (THP-1).Methods Cultured THP-1 cells were divided into several groups:blank control group receiving no treatment,amphotericin B groups treated with 2,4 and 8 mg/L amphotericin B separately,positive control group treated with 100 μg/L β-glucosan or 100 mg/L lipopolysaccharide.Real-time fluorescence-based quantitative PCR was performed to determine the mRNA expression of TNF-α and IL-8 after the THP-1 cells were treated with different stimuli for some durations.Enzyme-linked immunosorbent assay (ELISA) was conducted to detect the level of TNF-α in the culture supernatant of THP-1 cells after 24-hour treatment with 8 mg/L amphotericin B,and Western blot analysis to measure the levels of p38MAPK and phosphorylated p38MAPK after 30-minute treatment with 8 mg/L amphotericin B.Results After 6-hour treatment with 2,4 and 8 mg/L amphotericin B separately,the mRNA levels of TNF-α in THP-1 cells (7.55 ± 1.17,19.47 ± 2.91,57.22 ± 0.65) and IL-8 (2.98 ± 0.04,5.22 ± 1.35,11.82 ± 1.66) were all significantly higher than those in the blank control group (TNF-α:1.00 ± 0.07,P ＜ 0.01,0.001,0.001 respectively;IL-8:1.01 ± 0.23,P ＜ 0.01,0.001,0.001 respectively).After the treatment with 8 mg/L amphotericin B for 1,3,6 hours,the mRNA levels of TNF-α (8.61 ± 0.30,10.75 ± 0.08,56.98 ± 2.43) and IL-8 (2.63 ± 0.28,5.35 ± 0.98,11.73 ± 1.18) in THP-1 cells were all significantly higher than those in the blank control group (TNF-α:1.18 ± 0.17,P ＜ 0.05,0.01,0.001;IL-8:1.23 ± 0.11,P ＜ 0.05,0.01,0.001).After 24-hour treatment with 8 mg/L amphotericin B,the level of TNF-α in the culture supernatant of THP-1 cells was significantly higher than that in the blank control group (4 039.06 ± 223.87 ng/L vs.96.31 ± 0.26 ng/L,P ＜ 0.001).Conclusion Amphotericin B can promote the p38MAPK phosphorylation and increase the levels of TNF-α and IL-8 in human THP-1 cells in vitro,suggesting its immunomodulatory effects.