Abstract 1325: Novel recombinant rabbit monoclonal antibodies for cancer biology research

• Published in: Cancer research (Chicago, Ill.) Ill.), 2023-04, Vol.83 (7_Supplement), p.1325-1325
• Main Authors: Ball, Alexander, Hsieh, Yung Lin, Huang, Chun Kai, Huang, Sega, Hsieh, Ping Kuan, Wu, Shang Ru, Chang, Yue Yun, Liu, Jiming, Peng, Po Shin, Lin, Chia Yi
• Format: Article
• Language: English
• ISSN: 1538-7445; 1538-7445
• DOI: 10.1158/1538-7445.AM2023-1325

Recombinant monoclonal antibodies (rAbs) are superior tools for cancer biology research as they offer distinct advantages over standard polyclonal and hybridoma-generated monoclonal antibody reagents. Recombinant technology produces antibodies that can be defined at the primary sequence level and are characterized by consistent performance and supply. These rAb features are in stark contrast to traditional polyclonal and hybridoma-generated monoclonal antibodies, whose lack of dependability has been widely documented as a primary reason for data irreproducibility plaguing biomedical research. In an effort to respond to this challenge, GeneTex has established a recombinant antibody production platform combined with more rigorous validation protocols. The goal is to develop reliable recombinant rabbit monoclonal antibodies for reproducible performance in various experimental applications utilized routinely by cancer biologists. GeneTex’s rAb production protocol is based on the approach described by Starkie et al. (2016). This involves a multi-parameter fluorescence-activated single cell sorting (FACS)-based methodology to identify and isolate antigen-specific IgG+ memory B cells obtained from an immunized rabbit. The heavy and light chain variable region genes from selected cells are PCR-amplified and cloned into plasmids to produce full-length heavy and light chains for a single IgG. These constructs are subsequently introduced together into mammalian cells for expression, meaning that natural pairing of the chains is maintained. This manufacturing strategy allows application-specific testing (e.g., for western blot (WB), immunohistochemistry (IHC), and immunocytochemistry (ICC/IF), etc.) of clones during the antibody production process. Validation of antibodies is performed inhouse and, when possible, in relationships with academic or industry/pharma institutions where ideal samples and reagents are frequently more available. This recombinant monoclonal antibody production platform has created a series of well-validated antibodies against many important targets for cancer biology research. This includes reagents to study tumor immunobiology (e.g., PD-L1), hormone receptors (e.g., ER alpha and androgen receptor variants like ARV7), oncogenic RAS protein mutants (e.g., RAS G12D), transcription factors (e.g., NRF2), and epithelial-mesenchymal transition (EMT) (e.g., E-cadherin), among many others. Extensive validation for multiple applications was performed,