Isolation of ScFv antibodies of rP27Kip1 from phage display libraries constructed from immunized and non-immunized repertoires

Through mRNA extract, RT and a series of PCR, phage antibody libraries were constructed from rP27^{kip 1}-immunized and non-immunized mice. After only one round of selection with rP27^{kip 1}, clones from each library were chosen randomly and digested byTag I and Hinf I. 11 of 64 clones from the immunized animal had consistent restriction pattern, while none of the 64 clones from the non-immunized animal had, except that one had the same fragments pattern as that of the 11 clones. The 12 fragments were expressed inE. coli BL21(DE3)/pET-28b(+) system. ELISA showed that some of the fragments could bind to rP27^{kip 1} specifically. AU these results implied that specific antibody can be obtained by genetic engineering without hybridoma or many rounds of growth and panning selection.