OBJECTIVETo investigate the effect of formaldehyde exposure on the expression of inflammatory cytokines in human bronchial epithelial cells (16HBE cells).

METHODS16HBE cells were treated with formaldehyde with a concentration of 0, 0.04, 0.08, 0.16, 0.32, or 0.64 mmol/L for 24 hours, and MTT assay was applied to measure proliferative activity and calculate median lethal dose; 16HBE cells were exposed to formaldehyde with a concentration of 0, 0.04, 0.16, 0.64, or 1.20 mmol/L for 4 hours, MTT assay was applied to measure proliferative activity, and enzyme-linked immunosorbent assay was applied to measure the levels of Th1, Th2, and Th17 cytokines and tumor necrosis factor α(TNF-α) in cell supernatant.

RESULTSCompared with the control group, the 0.32-and 0.64-mmol/L exposure groups had significant decreases in cell viability (P<0.05); all exposure groups had reductions in interleukin(IL)-2 and IL-12, but no significant changes in interferon-γ and IL-10. In the 1.20-mmol/L exposure group, there was an increase in IL-4, with the increasing exposure dose, IL-5 and IL-6 tended to increase first and then decrease, and there was no significant change in IL-13; with the increasing exposure dose, IL-8 tended to increase first and then decrease, and there was no significant change in IL-17. In all the exposure groups, TNF-α increased and tended to increase significantly with the increasing exposure dose(P<0.05).

CONCLUSIONFormaldehyde exposure can cause imbalance between Th1 and Th2 cytokines secreted by 16HBE cells, as well as increased expression of IL-8 and TNF-α.