A rapid screening method for cell lines producing singly-tagged recombinant proteins using the "TARGET tag" system.

Area of Science:

• Biotechnology
• Molecular Biology
• Protein Engineering

Background:

• Recombinant production of extracellular glycoproteins in stable mammalian cell lines is crucial for obtaining high-quality proteins.
• Current methods for cell line development and protein purification are often time-consuming, limiting efficiency.

Purpose of the Study:

• To introduce a novel peptide tag, the TARGET tag, for rapid development of stable cell lines.
• To streamline the purification of recombinant extracellular glycoproteins.
• To reduce the overall time for cell line development and protein production.

Main Methods:

• Development of a 21-residue peptide tag (TARGET tag) for mammalian cell expression.
• Utilized an anti-tag antibody (P20.1) with a surface plasmon resonance (SPR)-based screening format.
• Implemented a sensitive SPR screening requiring only 20 microl of cell culture supernatants for direct and semi-quantitative screening at the 96-well culture scale.

Main Results:

• Established high-producing cell lines in less than a month, significantly reducing development time.
• Enabled milligram-scale purification of target proteins using a standardized protocol.
• Eliminated the need for secondary screening, re-cloning, or cell sorting, minimizing pre-production time.

Conclusions:

• The TARGET tag system offers a rapid and efficient method for stable mammalian cell line development.
• This approach significantly accelerates the production and purification of recombinant extracellular glycoproteins.
• The developed methodology streamlines bioprocessing, making it ideal for high-throughput protein production.