[Preparation of the monoclonal antibody against SOX4 protein and detection of SOX4 expression level in different tumor cell lines].

In the present study, we constructed a prokaryotic expression vector containing SOX4 protein encoding sequences. The GST-SOX4 soluble protein was expressed in Escherichia coli DH5alpha and purified by glutathione sepharose-4B. The purified recombinant protein was used to immunize Balb/C mice and the monoclonal antibody against SOX4 was prepared by using hybridoma technique. The titer of the antibody was determined as 1 x 10(5) by indirect ELISA. The specificity of the antibody was verified by Western blotting analysis. The monoclonal antibody specifically recognized the overexpressed exogenous SOX4 protein as well as endogenous SOX4 protein. The expression level of SOX4 protein in different cell lines and mouse tissues was detected by using the antibody. Differential expression of the protein was demonstrated by Western blotting. The data indicated that the antibody was specific. The antibody can be used as an important tool for further exploration of the role of SOX4 in tumorigenesis.