Expression Of YKL-40on Airway Epithelial Cells And Correlated With Eotaxin, GM-CSF And IL-5

Objective To observe the expression levels of YKL-40and airway-bone marrow signal molecules Eotaxin, GM-CSF, IL-5in airway epithelial cells, and analyze the correlation between YKL-40and IL-5, GM-CSF, Eotaxin in asthma.Methods Mouse tracheal epithelial cells were isolated and identified by Fluorescence immunohistochemistry. The cells were treated with, or without, OVA for24or48h. The relative levels of YKL-40, IL-5, GM-CSF and Eotaxin mRNA transcripts were determined by semi-quantitative RT-PCR and real time-PCR; their proteins were determined by ELISA and Western blot assays.Results The isolated mouse tracheal epithelial cells displayed epithelial cell features. The relative levels of YKL-40, IL-5, GM-CSF and Eotaxin mRNA transcripts in the OVA-treated cells were significantly higher than that in the controls (P<0.01) and the levels of YKL-40, Eotaxin, GM-CSF, IL-5proteins in the after24h,48h OVA-treated cells also significantly higher than that in the controls (P<0.01); the levels of YKL-40protein and mRNA in48h OVA were higher than that in24h OVA (P<0.05). Differently, the expression of YKL-40in48h control was similar with that in24h control (P>0.05). The stimulatory effect of OVA on the expression of these molecules appeared to be time-depentent. The levels of YKL-40expression were correlated positively with the levels of IL-5(r=0.882, P<0.01), GM-CSF (r=0.8077, P<0.01) and Eotaxin (r-0.9023, P<0.01) expression in the OVA-treated cells.Conclusion The cultured tracheal epithelial cells indicated that majority of cultured cells contained the features of epithelial cells. These data indicate that the influences of YKL-40on primary murine airway epithelial cells, treatment with OVA simultaneously enhanced YKL-40, IL-5, GM-CSF and Eotaxin expression in the cultured mouse tracheal epithelial cells in vitro. YKL-40protein concentration and mRNA expression levels were positively correlated with airway bone marrow signal IL-5, GM-CSF and Eotaxin in airway epithelial cells. We speculated that YKL-40is a glycoprotein secreted by epithelial cells, may be involved in the pathogenesis of asthma and its expression levels could serve as a biomarker of asthma.