Antibody discovery, at its core, is a numbers game. The challenge is not just finding an antibody that binds to a target. It is about identifying the best one, the rare high-affinity binders that will perform reliably in real-world applications. At Aviva Systems Biology, we have fine-tuned this search, combining high-throughput screening with recombinant antibody development to ensure every candidate meets the highest standards of specificity and performance.
Hunting for the Right B Cells
Every high-performance antibody we develop begins with a massive search through hundreds of millions of B cells. Our researchers use six-color flow cytometry to sort through rabbit blood cells, looking for the rare immune cells producing high-quality, antigen-binding IgG antibodies. Each step of the gating strategy refines the population—first excluding dead cells using a viability dye, then isolating singlets to remove clumps, and finally selecting for IgG-expressing B cells while excluding non-B cell lineages like CD4+, CD8+, and IgM+ populations.
Even after this careful selection, millions of candidates remain. The real challenge is finding the rare fraction, often less than 0.01 percent, that produce antibodies specific to the target antigen. To pinpoint these, we use biotinylated antigens stained with two distinct fluorophore-labeled anti-biotin antibodies. This dual-color strategy confirms true antigen binding and helps eliminate false positives caused by sticky proteins or non-specific interactions.
At the end of this exhaustive process, we are left with a precious handful—roughly one to three thousand double-positive, antigen-binding B cells. These cells hold the genetic blueprints for antibodies that may form the foundation of our next generation of high-performance recombinant products.
From Single Cells to Functional Antibodies
Once we have identified these rare B cells, the next step is capturing their genetic information. Using single-cell RT-PCR, we extract and amplify the genes encoding each antibody’s heavy and light chain variable regions. But discovery alone is not enough. We need to validate whether these candidates are worth pursuing.
To do that, we introduce the antibody genes into a cell-based expression system, producing small-scale antibody supernatants for functional screening. This eliminates the need to generate thousands of plasmids for testing, allowing us to accelerate the evaluation process.
From this pool of candidates, only the most promising ones move forward. The heavy and light chain genes from these top contenders are then cloned into final plasmids for stable and long-term recombinant antibody production. This ensures that every batch is precisely the same, eliminating the batch-to-batch variability often seen in traditional hybridoma-derived antibodies.
Why This Matters for Recombinant Antibody Development
Every step of this process, from cell sorting to gene cloning, expression, and screening, is designed with one goal in mind. We aim to generate the most reliable and reproducible recombinant antibodies possible. By leveraging advanced B-cell screening techniques, Aviva is not just identifying antibodies faster but ensuring that each one meets the rigorous demands of research and diagnostic applications.
And the transition to recombinant antibodies is more than just an industry shift. It is a necessary evolution in scientific research. With poor antibody specificity continuing to hinder reproducibility in biomedical studies, having a highly controlled, sequence-defined recombinant antibody is no longer just an advantage, it is an imperative.
At Aviva Systems Biology, we are committed to leading this charge, using cutting-edge techniques to bring the best possible antibodies to the researchers who rely on them.
Want to see how our recombinant antibodies perform in action? Explore our portfolio.
Infographic: Overview of Aviva’s recombinant antibody pipeline, from antigen design to clone selection and validation.
