Question

Which of the following systems would you use for the expression of an antibody? Explain you decision, why you would or would not use:

a. CHO

b. PERC.6 (human cell line)

c. Saccharomyces cerevisiae (yeast)

d. E.coli

e. Transgenic plant

Answer 1

Which of the following systems would you use for the expression of an antibody? Explain you decision, why you would or would not use:

a. CHO - Yes these cell lines can be used

• ​Chinese hamster ovary (CHO) cells are mammalian host epithelial cell lines derived from the ovary of the Chinese hamster and are used for the production of therapeutic antibodies.
• Mammalian cells based expression systems provides the benefits of proper protein folding, post translational modifications. These features are critical for proteins to remain biologically active.
• CHO cells provide several benefits for producing recombination proteins like ability to grow to high density, suitability for scale-up (large scale production), presence of glycosylation sites, stable expression etc.

b. PERC.6 (human cell line) - Yes these cell lines can be used

• ​PERC6 cells are derived from human embryonic retina and these cells are immortalized by transfecting the E1 genes from adenovirus 5 DNA (specific adenovector genes).
• These cell lines provide the advantage of being a human cell-based platform for producing recombinant proteins, high viable cell densities and high recombinant protein yields.

c. Saccharomyces cerevisiae (yeast) - Would not chose for antibody production

• Saccharomyces cerevisiae is a single-celled eukaryote and is extensively used for the  the production of recombinant proteins.
• Even though, yeast expression system would allow some post-translational modification of recombinant proteins, however, these modifications may not be similar as in human cells.
• mAbs approved for human therapy are only produced in CHO cells, NS0 murine myeloma cells, and Sp2/0 Mouse myeloma cells , PERC6 human cells.

d. E.coli - Would not chose for antibody production

• Since E.coli is a prokaryote, production of mAbs with the correct disulfide bonds is a major challenge.

e) Transgenic plant - Would not chose for antibody production

• Plants can be used as bioreactors for the production of therapeutic antibodies (even though plants do not have antibodies of their own), these modifications may not be similar as in human cells.