Transient Recombinant Antibody and Protein Expression Systems

Transient antibody expression (transient gene expression or transgene expression) in mammalian cells is important for the rapid and flexible production of antibodies. Antibody engineering can be performed to alter or abolish effector functions, change antibody isotype, or make precision modifications elsewhere in the antibody. Additionally, these systems allow for post-translational modifications (PTMs) to occur which can affect therapeutic antibody attributes.

Mammalian transient protein expression systems are ideal for the rapid production of highly biologically active proteins. Unlike other expression systems, mammalian cell lines allow for correct folding, especially of large proteins, and PTMs to be added which can all affect protein activity and aggregation.

Leinco offers contract protein and antibody production services using our proprietary Human Embryonic Kidney 293 (HEK293) and Chinese Hamster Ovary (CHO) transgene expression systems. Explore the capabilities and benefits of using customized mammalian recombinant antibody and protein manufacturing services below.

Recombinant Antibody, Transient Expression, Gene Synthesis, Cloning, Antibody and Proteins

HEK293 (Human Embryonic Kidney 293)

HEK293 cells are a specific cell line derived from human embryonic kidney cells grown in flasks or bioreactors. HEK293 cells are often used in cell biology and biotechnology to express antibodies and proteins. This cell line is ideal for the production of therapeutic proteins.


  • Reliable and flexible cell growth
  • Produce proteins similar to those humans naturally produce
  • Mammalian expression allows proper glycosylation and biologically active proteins with no need for refolding
  • Lower endotoxin levels
  • High transfection efficiency
  • Transient, stable expression

CHO (Chinese Hamster Ovary)

Leinco also offers the use of CHO cells, which were derived from the ovary of Chinese hamsters. CHO cells have similar benefits as HEK293 cells and are also extensively used in cell biology and medical research, particularly for commercial recombinant protein production of therapeutic antibodies and proteins.


  • Robust growth and adapt well in suspension cell culture
  • High recombinant protein yields and specific productivity
  • Simple genetic modification which is ideal for cloning, transfection, and protein production

Collaborative Approach

  • Highly experienced scientific and project management staff
  • Stringent quality and cGMP standards
  • Focused on transparent communication at every project stage and on recommending data-driven decisions
  • Achieve your goals more quickly using our biomarker immunoassay development and manufacturing experience for drug discovery and diagnostic applications
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