Recombinant antibody technologies have witnessed remarkable advancements and demonstrated significant clinical success. However, a major challenge associated with the use of murine monoclonal antibodies as a therapeutic is their immunogenicity causing a human anti-mouse antibody (HAMA) response. This response occurs when humans react to the foreign protein, causing complications from immune complex formations and resulting in the antibody treatment being ineffective. To tackle this issue, chimeric antibodies were created using genetic engineering techniques, combining human constant domains with mouse variable domains that recognized the human antigen of interest, thus preserving antibody specificity.1
Antibody humanization was further developed by modifying the mouse antibodies to be more similar to human antibodies by CDR (complementarity determining region) grafting. CDRs of non-human antibodies are grafted to human frameworks of high homology. Typically, some vernier zone residues (murine residues in framework regions) are also retained as they have been shown to affect CDR loop conformation and antibody affinity.2,3 Ultimately, humanized antibodies carry a lower risk of inducing immune responses in humans than mouse or chimeric antibodies.
The humanization process is as follows:
Sequence design and synthesis
Plasmid construction and preparation
Transient expression
Affinity purification
Stringent quality control
Affinity ranking
Biointron offers an antibody humanization service utilizing the CDR grafting and back mutation platform. Our service offers several advantages, including:
Guaranteed affinity (comparable to parental antibody / no cost if guaranteed affinity is not reached)
Fast turnaround time (only 4-5 weeks to obtain humanized antibodies)
Extensive experience and strong expertise (10+ years in humanized antibody design / we have produced 20,000 antibodies)
Yaghoub Safdari, Safar Farajnia, Mohammad Asgharzadeh & Masoumeh Khalili. (2013). Antibody humanization methods – a review and update. Biotechnology and Genetic Engineering Reviews, 29(2), 175-186. https://doi.org/10.1080/02648725.2013.801235
Harding, F. A., Stickler, M. M., Razo, J., & DuBridge, R. B. (2010). The immunogenicity of humanized and fully human antibodies: Residual immunogenicity resides in the CDR regions. MAbs, 2(3), 256-265. https://doi.org/10.4161/mabs.2.3.11641
Antibody glycosylation is the covalent attachment of carbohydrate (glycan) molecules to the protein chains of antibodies. This is a common type of post-translational modification that occurs within the cell's endoplasmic reticulum and Golgi apparatus.
In vitro display technologies are a group of methods used to display diverse antibody libraries on the surface of solid supports or particles like phage, yeast, ribosomes, and bacteria. They are powerful tools for the discovery and engineering of novel antibodies with desired binding properties and were first explored for antibody selection over 30 years ago.
Chimeric antibodies, formed by combining the variable regions of one species with the constant domains of another, are essential for various research fields, especially in vivo and in vitro studies. These hybrid antibodies maintain their antigen-binding specificity while offering flexibility in different research settings. This flexibility makes them highly valuable for biotherapeutic research, immunoassays, and diagnostic applications.
Biointron’s AbDrop & Cyagen’s HUGO-Ab is a high-throughput fully human antibody discovery platform that combines microdroplet-based single B cell screening with transgenic mice. This combination accelerates the discovery and development of fully human antibodies, reducing the time from target identification to therapeutic candidate to just three months.
