Antibody library screens using detergent-solubilized mammalian cell lysates as antigen sources

Abstract

High-throughput generation of antibodies against cellular components is currently a challenge in proteomics, therapeutic development and other biological applications. It is particularly challenging to raise antibodies that target membrane proteins due to their insolubility in aqueous solutions. To address these issues, a yeast display library of human single-chain antibody fragments (scFvs) was efficiently screened directly against detergent- solubilized and biotinylated lysates of a target cell line, thereby avoiding issues with membrane protein insolubility and eliminating the need for heterologous expression or purification of antigens. Antibody clones that specifically bind plasma membrane proteins or intracellular proteins were identified, depending on the biotinylation method applied. Antibodies against a predetermined target could also be identified using cell lysate as an antigen source as demonstrated by selecting an scFv against the transferrin receptor (TfR). When secreted from yeast and purified, the selected scFvs are active under physiological conditions in the absence of detergents. In addition, this method allows facile characterization of target antigens because it is compatible with yeast display immunoprecipitation. We expect that this method will prove useful for multiplex affinity reagent generation and in targeted antibody screens. © 2010 The Author. Published by Oxford University Press. All rights reserved.