The application of the cloning and expression of SMCY gender-specific fusion antigens with the corresponding polyclonal antibodies / 中国法医学杂志

ABSTRACT

Objective with the advantages of rapidity in detection protein, We selected the gender-specific amino acid sequence based on human SMCY and SMCX, cloned and expressed SMCY gender-specific fusion antigens. The rabbits were immunized with purified antigens to obtain the polyclonal antibodies. A new method was established for rapidly sex identification of forensic evidence samples by detecting SMCY antigens with the corresponding polyclonal antibodies. Methods We found three differential fragments by analyzing the sequence of human SMCY and SMCX. Then we cloned this three fragments and ligated as a new recombinant.This SMCY gender-specific fusion antigen gene was sub-cloned into pET-28a and expressed in Escherichia coli. The fusion antigen was purified by Ni-NTA column. The rabbits were immunized with purified antigen to produce the specific polyclonal antibodies.The reactivity of the polyclonal antibody was evaluated by ELISA and Western blotting. We developed a colloidal gold test strip for detecting the gender of human samples. Results We successfully selected gender-specific amino acid sequence, the SMCY gender-specific fusion antigen was expressed by prokaryotic expression and the polyclonal antibody was prepared by immunizing rabbit. The results of colloidal gold strip tests showed that there is a significant difference between male and female serums. Conclusion The results showed that the SMCY gender-specific fusion antigen could be recognized by the polyclonal antibody.The colloidal gold strip tests made by SMCY gender-specific fusion antigens and the corresponding polyclonal antibodies could be used for rapidly determining the gender of forensic evidence samples.