Abstract: Objective To investigate the effect of 1,25-dihydroxyvitamin D3 (1,25VD3) on house dust mites (HDM)-induced
expression of thymic stromal lymphopoietin (TSLP) in human airway epithelial cells in vitro. Methods Human airway
epithelial 16HBE cells were incubated with 200, 400, and 800 U/L in the absence or presence of 1,25VD3 (10-8 mol/L) for 6 h and
24 h, and TSLP mRNA and protein expressions in the cells were assessed using quantitative PCR and ELISA. Results 16HBE
cells incubated with HDM at 200, 400, and 800 U/L showed significantly increased TSLP mRNA and protein expressions (P<
0.05). Pretreatment of the cells with 1,25VD3 obviously lowered 400 U/L HDM-induced TSLP expressions (P<0.05), but 1,25VD3
added along with HDM in the cells did not produce significant effects on TSLP expressions (P=0.58). Conclusion Both 1,25VD3
and HDM can induce TSLP expression and release in 16HBE cells, but pretreatment with 1,25VD3 can decrease
HDM-augmented TSLP expression in the cells.