粉尘螨变应原Der f 36重组蛋白制备及其与Der p 36的交叉反应性研究OA北大核心CSTPCD

Objective:To prepare recombinant protein of group 36 allergen of Dermatophagoides farinae(Der f 36),to deter-mine its immunogenicity and bioinformatics analysis was performed.Methods:Nucleic acid sequence coding for Der f 36 was obtained and artificially synthesized,pET-28a(+)was inserted to construct pET-28a(+)-Der f 36 plasmid and transformed into BL21(DE3)receptor cells.After expressed and purified in BL21(DE3),recombinant allergen rDer f 36 was obtained,recombinant protein rDer f 36 was identified by SDS-PAGE and Western blot.Serum IgE binding rates of rDer f 36 was determined by IgE-ELISA.Cross-reactivity between rDer f 36 and rDer p 36 was detected by IgE-ELISA inhibition assay.HNEpC cells were cultured with rDer f 36 for 24 h and cytokines were detected.Bioinformatics softwares were used to analyze physicochemical properties and structures of Der f 36 and Der p 36.Results:Coding gene for Der f 36 was obtained with a total length of 690 bp,whose molecular weight was 25.6 kD;serum IgE binding rate of rDer f 36 was 42.1%by IgE-ELISA;IgE-ELISA inhibition assay showed that rDer p 36 had 40%(8/20)inhibition rate(>50%)for rDer f 36,with an average inhibition rate of 52.98%.Compared with control group,HNEpC cells cultured with rDer f 36 showed that IL-6,IL-8,IL-33,IL-25 and TSLP expressions had increased;bioinformatics analyses show that sequence consistency of Der f 36 and Der p 36 was 77.63%,with similar physicochemical properties.Secondary structure analysis showed that both of them contained α helix,β-turn and random coils,and content of random coils was the highest;structure of C2 domains was also highly overlapping(RMSD=0.046).Conclusion:Recombinant allergen rDer f 36 is successfully prepared with good immunogenicity,laying foundation for diagnosis and treatment of dust mite allergen single component.High similarity in physical and chemical properties,secondary structure,and tertiary structure between Der f 36 and Der p 36 determines their cross reactivity.