title: Development of enantioselective polyclonal antibodies to detect styrene oxide protein adducts.
abstract: Styrene has been reported to be pneumotoxic and hepatotoxic in humans and animals. Styrene oxide, a major reactive metabolite of styrene, has been found to form covalent binding with proteins, such as albumin and hemoglobin. Styrene oxide has two optical isomers and it was reported that the (R)-enantiomer was more toxic than the (S)-enantiomer. The purpose of this study was to develop polyclonal antibodies that can stereoselectively recognize proteins modified by styrene oxide enantiomers at cysteine residues. Immunogens were prepared by alkylation of thiolated keyhole limpet hemocyanin (KLH) with styrene oxide enantiomers. Polyclonal antibodies were raised by immunization of rabbits with the chiral immunogens. Titration tests showed all six rabbits generated high titers of antisera that recognize (R)- or (S)-coating antigens accordingly. No cross-reaction was observed toward the carrier protein (BSA). All three rabbits immunized with (R)-immunogen produced antibodies that show enantioselectivity to the corresponding antigen, while only one among the three rabbits immunized with (S)-immunogen generated antibodies with enantioselectivity of the recognition. The enantioselectivity was also observed in competitive ELISA and immunoblot analysis. Additionally, competitive ELISA tests showed that the immunorecognition required the hydroxyl group of the haptens. Immunoblot analysis demonstrated that the immunorecognition depended on the amount of protein adducts blotted and hapten loading in protein adducts. In summary, we successfully developed polyclonal antibodies to stereoselectively detect protein adducts modified by styrene oxide enantiomers.
authors.affiliation: Department of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
authors.forename: Shuijie
authors.initials: S
authors.lastname: Shen
authors.forename: Fan
authors.initials: F
authors.lastname: Zhang
authors.forename: Su
authors.initials: S
authors.lastname: Zeng
authors.forename: Ye
authors.initials: Y
authors.lastname: Tian
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Chai
authors.forename: Shirley
authors.initials: S
authors.lastname: Gee
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Hammock
authors.forename: Jiang
authors.initials: J
authors.lastname: Zheng
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology*; D000918:Antibody Specificity; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D004852:Epoxy Compounds / Q000737:chemistry*; D007106:Immune Sera / Q000276:immunology; D007118:Immunoassay / Q000379:methods*; D011506:Proteins / Q000032:analysis* / Q000737:chemistry* / Q000276:immunology; D013237:Stereoisomerism; D013343:Styrenes / Q000633:toxicity
chemical_list: D000906:Antibodies; D004852:Epoxy Compounds; D007106:Immune Sera; D011506:Proteins; D013343:Styrenes; C013690:styrene oxide