CSB’s VeRSaMAbs are recombinant monoclonal antibodies composed of cloned antibody genes engineered for enhanced performance. VeRSaMAbs are engineered to reduce background binding, contain AviTag technology for enhanced detection, and are made with a defined Fc for isotype control. VeRSaMAbs are identical in every production run, scalable to any quantity a customer needs, and will never run out.
What is a Recombinant Antibody?
Recombinant antibodies are generated using recombinant DNA technology. Defined antibody sequences are cloned into an expression vector and are introduced into an expression platform, such as mammalian CHO or HEK-293 cell lines. The resulting recombinant monoclonal antibodies are specific to a single epitope with large, consistent production yields after plasmid engineering and optimization.
In contrast, traditional monoclonal antibodies are derived by fusing a single B cell to a myeloma cell line to form a “hybridoma”. The hybridoma secretes the same antibody clone, but hybridomas are an unstable fusion of two genetically different cells, so can sometimes secrete multiple antibodies simultaneously, have variable production yields, and are subject to genetic drift as the cell grows over time, which can lead to antibody variability either in sequence or post-translational modifications.
Traditional polyclonal antibodies are a mixture of antibodies from the serum of animals that have been immunized against a particular antigen. These serum samples consist of antibodies secreted from many different B cells, resulting in a heterogenous population of antibodies against different epitopes of the same target.
Polyclonal antibodies are useful for many purposes, but also have several distinct limitations, including variability based on different times of antibody isolation from a given animal, high variability across different animals, limited supply, and potential for high background due to the mixed composition of antibodies. In many cases, vendors that sell polyclonal antibodies will change the lot number of a polyclonal antibody without changing the catalog number, meaning that you could receive a completely different polyclonal antibody from a completely different animal even though the catalog number is identical. Such practices have contributed to the ongoing reproducibility crisis for reagent antibodies.1–3,4
Advantages of Recombinant Monoclonal Antibodies
Recombinant antibodies from CSB resolve many of the limitations of traditional polyclonal and hybridoma-based monoclonal antibodies5–7. VeRSaMAbs are engineered for:
- Reduced background binding through Fc modifications
- Enhanced detection using AviTag technology
- Ease of Fc engineering for isotype switching and other modifications
- Batch-to-batch reproducibility
- Scalability to any quantity needed
- Elimination of supply issues
Ease of Fc engineering for isotype switching and other modifications
VeRSaMAbs are engineered with a defined murine IgG2a Fc isotype and can also be further engineered to best match experimental requirements. Our antibody constructs are designed for rapid engineering to switch between isotypes or other formats as needed. Contact us if you are interested in one of our VeRSaMAbs with a customized modification!
Batch-to-batch reproducibility
Since the exact sequence of each VeRSaMAb is known, we ensure that every batch produced is identical, eliminating concerns related to variability between lots. Each new lot of VeRSaMAb is validated and compared to prior lots to ensure the consistent reproducibility of each MAb.
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CD28 antibody (CSB0012) |
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IL3RA antibody (CSB0004) |
Figure 1. Lot-to-lot comparison of CD28 antibody (CSB0012) (top) and IL3RA antibody (CSB0004) (bottom) in extracellular flow cytometry on HEK-293F cells. Each panel was derived using a different production lots of the same antibody.
S:B is comparable along with S:N
Ease of scalability
Recombinant antibodies are readily scaled by introducing the expression vector containing the known antibody sequence into a defined host cell. This method of antibody production enables fast, consistent, and predictable manufacturing of recombinant antibodies, with the ability to scale the amount of antibody as small or as large as needed.
Elimination of supply issues
Since the sequence of recombinant antibodies are known, they can be produced identically over and over again for as long as you need them. In contrast, production of polyclonal antibodies is limited to the longevity of the immunized host, while the longevity and reproducibility of hybridoma-based monoclonal antibodies is limited by the health and stability of the hybridoma. Consistency and homogeneity of supply is especially important for critical reagents used in diagnostic and clinical trial-based applications.
References
(1) Baker, M. Antibodies Are the Workhorses of Biological Experiments, but They Are Littering the Field with False Findings. A Few Evangelists Are Pushing for Change. 3.
(2) Voskuil, J. Commercial Antibodies and Their Validation [Version 2; Peer Review: 3 Approved]. F1000Research 2014, 3 (232). https://doi.org/10.12688/f1000research.4966.2.
(3) Voskuil, J. L. A. The Challenges with the Validation of Research Antibodies. F1000Res 2017, 6, 161. https://doi.org/10.12688/f1000research.10851.1.
(4) Weller, M. G. Quality Issues of Research Antibodies. Anal Chemistry Insights 2016, 11, ACI.S31614. https://doi.org/10.4137/ACI.S31614.
(5) Bradbury, A.; Plückthun, A. Reproducibility: Standardize Antibodies Used in Research. Nature 2015, 518 (7537), 27–29. https://doi.org/10.1038/518027a.
(6) Dove, A. Agreeable Antibodies: Antibody Validation Challenges and Solutions. Science 2017. https://doi.org/10.1126/science.opms.p1700116.
(7) Weller, M. G. Ten Basic Rules of Antibody Validation. Anal Chemistry Insights 2018, 13, 117739011875746. https://doi.org/10.1177/1177390118757462.