Published online 8 May 2006
Methods Online |
Phage display mediated immuno-PCR
1 State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences Wuhan 430071, China 2 State Key Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences Beijing 100101, China 3 Graduate School, Chinese Academy of Sciences Beijing 100039, China 4 Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention Beijing 100052, China
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Received February 12, 2006. Revised February 27, 2006. Accepted March 31, 2006.
Immuno-PCR (IPCR) is a powerful detection technology in immunological study and clinical diagnosis due to its ultrasensitivity. Here we introduce a new strategy termed phage display mediated immuno-PCR (PD-IPCR). Instead of utilization of monoclonal antibody (mAb) and chemically bond DNA that required in the conventional IPCR, a recombinant phage particle is applied as a ready reagent for IPCR experiment. The surface displayed single chain variable fragment (scFv) and phage DNA themselves can directly serve as detection antibody and PCR template, respectively. The aim of the design is to overcome shortcoming of low detection sensitivity of scFv so as to largely facilitate the real application of scFv in immunoassay. The idea has been demonstrated by applying hantaan virus nucleocapsid protein (NP) and prion protein (PrP) as detection targets in three experimental protocols (indirect, sandwich and real-time PD-IPCR assays). The detection sensitivity was increased 1000- to 10 000-folds compared with conventional enzyme-linked immunosorbent assays (ELISAs). This proof-of-concept study may serve as a new model to develop an easy to operate, low cost and ultrasensitive immunoassay method for broad applications.