[Recombinant expression of rift valley fever virus nucleocapsid protein and generation of rabbit polyclonal...

Objective Prokaryotic expression and purification of the Rift Valley fever virus (RVFV) nucleocapsid protein (NP) were performed to establish a basis for serum NP antibody detection and to produce specific polyclonal antibodies against NP. Methods The constructed pET28a-ZH501-NP prokaryotic expression plasmid was transformed into BL21(DE3) competent cells, and the expression of the recombinant protein NP was induced by isopropyl-β-D-thiogalactoside (IPTG). The recombinant protein NP was purified using HisTrap^TM HP and mixed with Freund's complete and incomplete adjuvants to immunize New Zealand white rabbits. NP polyclonal antibodies were prepared, and their specificity was identified by indirect immunofluorescence (IFA) and Western Blotting. Results The prokaryotic expression plasmid was successfully constructed, and expression was successfully induced in BL21(DE3) competent cells. The recombinant protein NP was expressed in the form of inclusion bodies. Western Blotting and IFA assays indicated that the polyclonal antibody could specifically recognize RVFV NP. Conclusion The pure and effective expression of RVFV NP protein was achieved. The experimental conditions for the indirect ELISA using it as the coating antigen were explored. Simultaneously, specific polyclonal antibodies against RVFV NP were prepared, providing technical support for the establishment of a reliable rapid diagnostic technology for RVF and the research and evaluation of new RVFV vaccines.