Developing selection strategy for CHO-K1 cell line that secretes scfv-Fc fusion antibodies using ClonePix2

Year 2022, Volume: 5 Issue: 3, 533 - 545, 15.12.2022

Aylin Özdemir Bahadır

https://doi.org/10.38001/ijlsb.1112823

Abstract

In the pharmaceutical industry, biopharmaceuticals (biologics) are gaining market share. There has been a dramatic increase in the sale and market penetration of monoclonal antibodies in particular. Typically, therapeutic antibodies are produced using high-expression, clonal, or recombinant CHO cell lines. CHO cells dominate the market as a commercial production host due to their ease of use, built-in regulatory records, and security profiles. While traditional limiting-dilution and cloning-ring regulations are frequently used to select mammalian cell lines that produce high levels of proteins, they have a number of drawbacks. ClonePix2 is a fully automated, single cell-based clone selector that significantly increases the likelihood of rapidly selecting high-production clones with high monoclonality. Scfv-Fc recombinant antibody structures with a variety of therapeutic advantages have gained prominence in recent years. Single cell cloning of CHO cells expressing the scfv-Fc fusion protein, which differs from the classical immunoglobulin structure, was performed in situ using the ClonePix2 device using FITC-tagged anti-Fc and anti-H+L antibodies. The fluorescent intensity parameters of the resulting cell clones were analyzed. Additionally, ELISA was used to determine the production capacities of the best clones. As a result, it was established that anti-Fc antibody recognizes the scfv-Fc fusion protein in a semi-solid environment, enabling the identification of higher production clones.

Keywords

Biopharmaceuticals, cell-line, high-producer, scfv-Fc antibody, ClonePix2

Supporting Institution

This work has been supported by the TÜBİTAK, Marmara Research Center, Medical Biotechnology Department of Life Sciences.

Thanks

I would like to express my gratitude to Esin Bayralı, Gökhan Güler and Evrim Tekel for their excellent technical assistanc, as well as to Koray B. Balcioglu, H. Ümit Öztürk, Hivda Ülbeği Polat, Müge Serhatlı, Hilal Yazıcı Malkoçoğlu and Melis Denizci Öncü for their comments on this article.

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