Isolation and identification of a novel WSSV nucleocapsid protein by cDNA phage display using an scFv antibody.
In a previous study, a scFv phage display library against white spot syndrome virus (WSSV) was constructed and yielded a clone designated A1 with conformational specificity against native but not denatured viral antigen. Although the clone A1 has been used successfully as a diagnostic antibody, its precise target antigen has not been elucidated. A different strategy was adopted involving the construction of a second T7 phage display library utilizing mRNA isolated from shrimp infected with WSSV. Following RT-PCR and T7 phage library construction, phages displaying the candidate epitope were selected with A1 scFv. Since successive enrichment steps were not associated with an increased titer of the phages, enrichment after successive tests was confirmed by PCR resulting in the preferred selection of a specific DNA sequence encoding a novel nucleocapsid protein WSSV388. Immune electron microscopy revealed that WSSV388 is located on the nucleocapsid. This result demonstrated that unknown antigen could be identified by phage display using the epitope conformation dependent scFv.
Xiao
Nan
N
Institute of Hydrobiology, Chinese Academy of Sciences, 7 Southern East Lake Road, Wuchang, Wuhan, Hubei 430072, PR China.
Zhang
Xiaohua
X
Dai
Linfeng
L
Yuan
Li
L
Wang
Yuzhen
Y
Zhang
Min
M
Xu
Tao
T
Dai
Heping
H
D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology; D015723:Gene Library; D016253:Microscopy, Immunoelectron; D019251:Nucleocapsid / Q000737:chemistry* / Q000276:immunology; D019590:Nucleocapsid Proteins / Q000276:immunology / Q000302:isolation & purification*; D019151:Peptide Library; D046848:White spot syndrome virus 1 / Q000737:chemistry* / Q000276:immunology
D000914:Antibodies, Viral; D019590:Nucleocapsid Proteins; D019151:Peptide Library