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bioRxiv · 10.1101/551382

Functional diversification of hybridoma produced antibodies by CRISPR/HDR genomic engineering

Abstract

Hybridoma technology is instrumental for the development of novel antibody therapeutics and diagnostics. Recent preclinical and clinical studies highlight the importance of antibody isotype for therapeutic efficacy. However, since the sequence encoding the constant domains is fixed, tuning antibody function in hybridomas has been restricted. Here, we demonstrate a versatile CRISPR/HDR platform to rapidly engineer the constant immunoglobulin domains to obtain recombinant hybridomas which secrete antibodies in the preferred format, species and isotype. Using this platform, we obtained recombinant hybridomas secreting Fab fragments, isotype switched chimeric antibodies, and Fc-silent mutants. These antibody products are stable, retain their antigen specificity, and display their intrinsic Fc-effector functions in vitro and in vivo. Furthermore, we can site-specifically attach cargo to these antibody products via chemo-enzymatic modification. We believe this versatile platform facilitates antibody engineering for the entire scientific community, empowering preclinical antibody research. One Sentence SummaryWe demonstrate a universal CRISPR/HDR based platform for rapid genetic engineering of hybridomas to obtain functionally diverse antibody isotype panels in the species and format of choice.

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BibTeXRIS

van der Schoot, J. M. S., Fennemann, F. L., Valente, M., Dolen, Y., Hagemans, I. M., Becker, A. M. D., Le Gall, C. M., van Dalen, D., Cevirgel, A., van Bruggen, J. A. C., Engelfriet, M., Fransen, M. F., Caval, T., Bentlage, A. E. H., Nederend, M., Leusen, J. H. W., Heck, A. J. R., Vidarsson, G., Figdor, C. G., Verdoes, M., Scheeren, F. A.. 2019-02-15. Functional diversification of hybridoma produced antibodies by CRISPR/HDR genomic engineering. https://doi.org/10.1101/551382

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