Relationship between Sialyl Glycan Expression on T Cells and Endophenotypes of Childhood Asthma

Background: Asthma is a common chronic inflammatory disease in children. Helper T (Th) cells and regulatory T cells (Tregs) play important role of the pathogenesis of asthma and lead to various endophenotypes. The expression level of functional adhesion molecules, sialyl Lewis x (CD15s) and sialyl 6-sulfo Lewis x (G152) glycan, on memory Th cells are associated with the severity of allergic diseases. The association between the expression level of sialyl glycans and asthma endophenotypes remain unclear and needs further investigation. Methods: Thirty-one asthma patients and nineteen healthy controls aged 6 to 15 were recruited from NTUCH and a clinic in 2015 and 2016. The percentage of glycan-expressing cells among memory Th cells was detected by flow cytometry. The association between the expression of sialyl glycan and several asthma endophenotypes, such as severity, blood eosinophils and serum total IgE level, was investigated. Results: CD15s and G152 glycans on memory Th cells are upregulated in asthma patients compared with healthy controls. The population of suppressive CD15s+ Tregs among CD4+ T cells was significantly lower in the moderate to severe group of asthma. Blood eosinophils and serum total IgE and, as two indicators of the exacerbation of asthma were associated with G152 glycan and G159 glycan respectively. Conclusions:CD15s and G152 glycans were associated with the current status of childhood asthma. Patients expressing the higher level of G152 glycan and less G159 glycan on central helper memory T cells would have higher risk on exacerbation.