ABSTRACT
【Objective】 To establish a stable human megakaryocytic cell line with low expression of Ley antigen to further study the role of Ley on activation of platelets. 【Methods】 The expression level of the Ley antigen in a human megakaryocytic cell line, DAMI, was determined using Western Blot and flow cytometry. The expression level of genes that encode fucosyltransferase (FUTs), which was involved in the biosynthesis of Ley antigen, was also determined to identify the candidate genes to be knocked out. The candidate FUT gene was knocked out via a CRISPR/Cas 9 gene knockout system and cells with low Ley antigen expression were sorted by flow cytometry. The sorted cell line was cultured and characterized. 【Results】 The Ley was expressed intensively on DAMI cell. FUT1 and FUT4 mRNA was expressed relatively higher, both may be key enzymes for the biosynthesis of the Ley antigen. In the DAMI cell line with the knockout of FUT1 gene, the expression of the Ley adntigen was remarkedly reduced, while cell proliferation was not affected compared to the wildtype control cells. 【Conclusions】 Since various FUTs contributes to the biosynthesis of the Ley antigen, the knockout of the primary one of them cannot totally block its biosynthesis, but only reduce its expression. In this study, a stable FUT gene knockout human megakaryocyticcell line is established using CRISPR/Cas 9 technology, which provides basis for the study of the impact of the Ley antigen on platelet functions.