Objective To investigate the possible mechanism of kinesin family member 3A (KIF3A) taking part in the regulation of asthma airway inflammation, so as to provide a new target and direction for asthma treatment. Methods Female C57BL/6 mice were randomly divided into asthma group (n=10) and control group (n=10). Western blotting and immunohistochemistry (IHC) were performed to detect the expression of KIF3A in the 2 groups. After human bronchial epithelial 16HBE cells were intervened using phosphate buffer solution (PBS) and house dust mite (HDM), Western blotting and RT-PCR were adopted to detect the KIF3A expression. Moreover, the lentiviral vectors of KIF3A overexpression (LV-KIF3A-45894-J2, LV-KIF3A) and knock-down (LV-KIF3A-RNAi-81183-1, RNAi) were constructed and then transfected into 16HBE cells, and the blank lentiviral vectors and those containing negative control sequence served as controls, respectively. The binding of KIF3A to β-arrestin in the overexpressed cells was detected by immunoprecipitation, while the expression level of β-catenin in each group of cells was determined by Western blotting and RT-PCR. The effect of differential expression of KIF3A on the expression of chemokines CCL-17 and CCL-26 was also determined. Results In animal models, the expression of KIF3A was significantly lower in the asthma mice than the control mice (P < 0.05). In vitro study indicated that HDM intervention decreased the expression of KIF3A at protein and mRNA levels in 16HBE cells, though there was no statistical difference (P>0.05). The RT-PCR and Western blotting results showed that the expression of KIF3A were increased in the LV-KIF3A transfected cells (P < 0.05) and decreased in the RNAi treated cells (P < 0.05). Immunoprecipitation confirmed the binding of KIF3A to β-arrestin. No significant difference was found in the total amount of β-catenin protein between the LV-KIF3A transfected cells and the RNAi treated cells. Compared with the corresponding cells, the mRNA level of β-catenin was significantly lower in the RNAi treated cells (P < 0.0001), but no such difference was seen in the LV-KIF3A transfected cells. The RT-PCR results suggested that the levels of chemokines CCL-17 and CCL-26 were increased in the RNAi treated cells (P < 0.001), while decreased in the LV-KIF3A transfected cells (P < 0.05) as compared with their control cells. Conclusion KIF3A binds to β-arrestin in the Wnt/β-catenin pathway, and is involved in asthmatic airway epithelial inflammation by regulating the expression of chemokines CCL-17 and CCL-26.
