Isolation of Single Chain Variable Fragments against Six Esters of Pyrethrins by Subtractive Phage Display

Abstract

Recombinant antibodies (rAbs) are a new diagnostic test for immulogical detection. To date, there are no reports about anti-pyrethrins rAbs. Here we describe the generation of monomeric and dimeric single chain variable fragments (scFvs) with affinity for six esters of pyrethrins using a subtractive phage display technology. First, scFv libraries with long-linker (Ger₄Ser)₃ and short-linker (Ger₄Ser) were established to contain 1.04×10⁷ or 6.07×10⁶ transformants. After four rounds of panning, phage ELISA demonstrated that three clones (E2, F2, and H7) showed higher affinity from the long-linker library, and clones (h6, a5) exhibited better antibody activity to pyrethrin I and II from the short-linker library. The scFv candidates were sequenced to identify the specific antibody response against pyrethrins. Isolated scFvs constitute valuable tools for real-time detection of pyrethrins. In addition, the subtractive phage display provides a simple approach for isolation of scFvs.