Chemical Modification of the Yeast Cell Surface Allows the Switch Between Display and Soluble Secretion of Full-Length Antibodies.

The classical yeast surface display (YSD)-based antibody hit discovery relies on the enrichment of candidates from large antibody fragment libraries by fluorescence-activated cell sorting (FACS), followed by sequencing of the remaining diversity. The sequences of hit candidates are then transferred into plasmids, which allow their expression as full-length IgG in mammalian cells. After production and downstream processing, antibodies are further qualified in biochemical and functional assays.

Selection of Antibodies with Tailored Properties by Application of High-Throughput Multiparameter Fluorescence-Activated Cell Sorting of Yeast-Displayed Immune Libraries.

In this study, we present a multiparameter screening procedure for the identification of target-specific antibodies with prescribed properties. Based on B cell receptor gene repertoires from transgenic rats, yeast surface display libraries were generated, and high-affinity human antibodies were readily isolated. We demonstrate that specific desirable features, i.

Semi-synthetic vNAR libraries screened against therapeutic antibodies primarily deliver anti-idiotypic binders.

Anti-idiotypic binders which specifically recognize the variable region of monoclonal antibodies have proven to be robust tools for pharmacokinetic studies of antibody therapeutics and for the development of cancer vaccines. In the present investigation, we focused on the identification of anti-idiotypic, shark-derived IgNAR antibody variable domains (vNARs) targeting the therapeutic antibodies matuzumab and cetuximab for the purpose of developing specific capturing ligands. Using yeast surface display and semi-synthetic, CDR3-randomized libraries, we identified several highly specific binders targeting both therapeutic antibodies in their corresponding variable region, without applying any counter selections during screening.

Engineering bispecific antibodies with defined chain pairing.

Bispecific IgG-like antibodies can simultaneously interact with two epitopes on the same or on different antigens. Therefore, these molecules facilitate novel modes of action, which cannot be addressed by conventional monospecific IgGs. However, the generation of such antibodies still appears to be demanding due to their specific architecture comprising four different polypeptide chains that need to assemble correctly.

Generation of human bispecific common light chain antibodies by combining animal immunization and yeast display.

Bispecific antibodies (bsAbs) pave the way for novel therapeutic modes of action along with potential benefits in several clinical applications. However, their generation remains challenging due to the necessity of correct pairings of two different heavy and light chains and related manufacturability issues. We describe a generic approach for the generation of fully human IgG-like bsAbs.

Balancing Selectivity and Efficacy of Bispecific Epidermal Growth Factor Receptor (EGFR) × c-MET Antibodies and Antibody-Drug Conjugates.

Bispecific antibodies (bsAbs) and antibody-drug conjugates (ADCs) have already demonstrated benefits for the treatment of cancer in several clinical studies, showing improved drug selectivity and efficacy. In particular, simultaneous targeting of prominent cancer antigens, such as EGF receptor (EGFR) and c-MET, by bsAbs has raised increasing interest for potentially circumventing receptor cross-talk and c-MET-mediated acquired resistance during anti-EGFR monotherapy. In this study, we combined the selectivity of EGFR × c-MET bsAbs with the potency of cytotoxic agents via bispecific antibody-toxin conjugation.

A generic approach to engineer antibody pH-switches using combinatorial histidine scanning libraries and yeast display.

There is growing interest in the fast and robust engineering of protein pH-sensitivity that aims to reduce binding at acidic pH, compared to neutral pH. Here, we describe a novel strategy for the incorporation of pH-sensitive antigen binding functions into antibody variable domains using combinatorial histidine scanning libraries and yeast surface display. The strategy allows simultaneous screening for both, high affinity binding at pH 7.

REAL-Select: full-length antibody display and library screening by surface capture on yeast cells.

We describe a novel approach named REAL-Select for the non-covalent display of IgG-molecules on the surface of yeast cells for the purpose of antibody engineering and selection. It relies on the capture of secreted native full-length antibodies on the cell surface via binding to an externally immobilized ZZ domain, which tightly binds antibody Fc. It is beneficial for high-throughput screening of yeast-displayed IgG-libraries during antibody discovery and development.

Therapeutic antibody engineering by high efficiency cell screening.

In recent years, several cell-based screening technologies for the isolation of antibodies with prescribed properties emerged. They rely on the multi-copy display of antibodies or antibody fragments on a cell surface in functional form followed by high through put screening and isolation of cell clones that carry an antibody variant with the desired affinity, specificity, and stability. Particularly yeast surface display in combination with high-throughput fluorescence-activated cell sorting has proven successful in the last fifteen years as a very powerful technology that has some advantages over classical generation of monoclonals using the hybridoma technology or bacteriophage-based antibody display and screening.