Bioinformatic Prediction and Production of Four RecombinantProteins from Different Developmental Stages of Trichinella spiralisand Testing of Their Diagnostic Sensitivity in Mice

Background: trichinellosis is a serious food-borne parasitic zoonosis, thus finding high quality antigens is the key to serodiagnosis of trichinosis. this article reports the characterization and sensi-tivity of four recombinant proteins expressed by four genes (wn10, zh68, t668, and wm5) from different developmental stages of trichinella spiralis for the diagnosis of trichinellosis in mice. methods: this study was conducted in jilin university and national institute of parasitic diseases of chinese center for disease control and prevention in 2017-2018. the structures and functions of the proteins encoded by four genes were predicted by bioinformatics analysis. the four genes were cloned and expressed, and the recombinant proteins were purified. anti-trichinella igm and igg antibodies in the sera of mice infected with t. spiralis from 1-45 d post-infection (dpi) were evaluated by elisa. results: the optimal antigen epitopes of four proteins (p1, p2, p3, and p4) encoded by the four genes from t- and b-cells were predicted, and four purified recombinant proteins (r-p1, r-p2, r-p3, and r-p4) were successfully produced. for igm, the antibody levels detected by the four recombinant antigens were approximately equal to the cut-off value. anti-trichinella igg antibodies were first detected by r-p1 at 8 dpi, followed by r-p2, r-p3, and r-p4 at 10 dpi, 14 dpi, and 16 dpi, respectively, and the antibody levels remained high until 45 dpi. conclusion: the recombinant antigens r-p1, r-p2, r-p3, and r-p4 could be antigens that react with antibodies, they showed high sensitivity in the detection of anti-trichinella igg antibodies in mice. among these proteins, r-p1 may be a candidate antigen for the detection of anti-trichinella igg anti-bodies in the early infection phase and exhibited the best sensitivity among the antigens