In this webinar, the featured speaker will discuss the rapid single B-cell cloning workflow that ChemPartner is using to discover rabbit antibodies. After a quick primer on the technical equipment they are using (Beacon), they will use an internal anti-CD28 (cluster of differentiation 28) rabbit antibody discovery case study to go over the individual steps of the rabbit workflow. Attendees will get an understanding of the Beacon system, the scientific background of the workflow, as well as an overview of the characteristics of the antibodies discovered in this case study.
CD28 is a costimulatory receptor for T-cell activation, and CD28 binding antibodies are in clinical development to block or promote T-cell activation. CD28-specific binding domains are also used in bi- or tri-specific antibody formats to generate T-cell-engaging antibodies. They set out to generate CD28-specific monoclonal antibodies (mAbs) from rabbits using a single B-cell cloning workflow on the Beacon system.
The Beacon system enables rapid antibody discovery using a function-first approach. Antibody-secreting cells (ASCs) are isolated from immunized animals and placed individually into nanowells (pens) of a Beacon chip. Due to the small size of the pens, the secreted antibody concentration reaches µg/ml levels within minutes, and the functional properties of the antibodies can be tested in sequential or multiplexed bead-based assays with a fluorescent readout. Typical assay duration is 30-60 minutes.
Rabbits were immunized with Chinese hamster ovary cells (CHOK1) stably transfected to carry human CD28 (hCD28) on their surface. Serum samples showed clear, yet low specific titers for hCD28. At the end of the immunization schedule, memory B-cells were isolated from blood using Ficoll separation and magnetic sorting. B-cells were cultured in an activation media, and cells were analyzed after four and five days of activation. During the activation period, the average cell size increased and cells proliferated roughly 15-fold until day five, with cell numbers unchanged after that. Flow cytometry showed a reduction of surface immunoglobulin G (IgG) and a clear increase of intracellular IgG during activation, consistent with a shift from B-cells to antibody-secreting cells.
In summary, the rabbit antibody discovery workflow on the Beacon enabled rapid screening of a large number of ASCs and identification of antigen-specific antibodies within four days of obtaining peripheral blood mononuclear cells (PBMCs) from immunized rabbits. cDNA generation and export happened on the day of the Beacon run, and cDNA amplification added another day to the workflow. The generation of constructs and expression of antibodies for further characterization was completed in less than one month. Overall, the method was robust and substantially reduced the hands-on time for rabbit antibody discovery, especially compared to the traditional hybridoma approach.
Join this webinar to gain insights into ChemPartner’s innovative single B-cell cloning workflow and the groundbreaking Beacon system.
Andreas Loos, PhD, Director Biologics Discovery ChemPartner
Dr. Andreas Loos joined ChemPartner in 2021 as the Director of Biologics Discovery and he leads the biologics discovery team at ChemPartner’s South San Francisco site. The team was one of the first adopters of Berkeley Lights’ (BLI) Beacon® technology and has successfully used the platform since 2019 to conduct antibody discovery projects.
Prior to joining ChemPartner, Dr. Loos led an antibody discovery and assay development group at Aridis Pharmaceuticals. During his PhD and post-doctoral training in Gent (Belgium), Heidelberg (Germany) and Vienna (Austria), he studied production and post-translational modifications of biologics in plants.
Who Should Attend?
This webinar will appeal to:
- Biologics Discovery Scientists
- Upper management that will decide on the discovery modality for an antibody program
- Scientists interested in antibody discovery
What You Will Learn
Attendees will gain insights into:
- Rabbit antibody discovery using the Beacon single-cell cloning process
- The scientific background of the workflow
- An overview of the characteristics of the antibodies discovered in this case study
Shanghai ChemPartner, which includes ChemPartner and ChemPartner Biologics, is a CRO/CDMO offering a broad range of drug discovery, development, and manufacturing services.
ChemPartner is a science-based, technology-driven global CRO and CDMO offering a broad range of services including discovery chemistry, biology, pharmacology, DMPK, and exploratory toxicology as well as biologics discovery, CMC development, and manufacturing.
ChemPartner serves a diverse global client base as more and more pharmaceutical and biotech companies look for alliance partners to provide intellectual contributions and exceptional technical expertise. With locations and representatives in China, Europe, and the US, ChemPartner is uniquely positioned to be a true biopharmaceutical alliance partner.