title: Detection and precipitation of hepatitis B core antigen using a fusion bacteriophage.
abstract: The nucleocapsids of hepatitis B virus (HBV) are made of 180 or 240 subunits of core proteins or known as core antigens (HBcAg). A fusion bacteriophage bearing the WSFFSNI sequence that interacts tightly to HBcAg was employed as a diagnostic reagent for the detection of the antigen using the phage-enzyme-linked immunosorbent (phage-ELISA), dot blot and immunoprecipitation assays. The results from phage-ELISA and dot blot assay showed that as low as 10 ng of HBcAg can be detected optimally by 1.0x10(12) pfu/ml fusion M13 bacteriophage. The sensitivity of the dot blot assay corresponds with that of the phage-ELISA. HBcAg in HBV positive serum samples can also be detected using the fusion phage via the phage-ELISA and phage-dot blot assay. The phage cross-linked to cyanogen bromide (CNBr) activated agarose can also be used to precipitate HBcAg in bacterial lysate. The optimum amount of phage needed for cross-linking to 1 g of agarose is about 7.0x10(6) pfu/ml which could also precipitate purified and unpurified HBcAg in bacterial lysate. This study demonstrates the potential of fusion bacteriophage bearing the sequence WSFFSNI as a diagnostic reagent and a ligand for the detection and purification of HBcAg respectively.
authors.affiliation: Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, University Putra Malaysia, UPM 43400, Serdang, Selangor, Malaysia.
authors.forename: Siti Salwa
authors.initials: SS
authors.lastname: Hasmoni
authors.forename: Khatijah
authors.initials: K
authors.lastname: Yusoff
authors.forename: Wen Siang
authors.initials: WS
authors.lastname: Tan
mesh_terms: D017104:Bacteriophage M13 / Q000737:chemistry*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006509:Hepatitis B / Q000175:diagnosis*; D006512:Hepatitis B Core Antigens / Q000302:isolation & purification*; D006515:Hepatitis B virus / Q000302:isolation & purification*; D006801:Humans; D015151:Immunoblotting; D047468:Immunoprecipitation; D011993:Recombinant Fusion Proteins / Q000737:chemistry*
chemical_list: D006512:Hepatitis B Core Antigens; D011993:Recombinant Fusion Proteins