A big cheese in biotherapeutics: Lactoyl leucine and isoleucine are
bioavailable alternatives for canonical amino acids in cell culture
media
Abstract
Increasing demands for protein-based therapeutics such as monoclonal
antibodies, fusion proteins, bispecific molecules and antibody fragments
require researchers to constantly find innovative solutions. To increase
yields and decrease costs of next generation bioprocesses, highly
concentrated cell culture media formulations are developed but often
limited by the low solubility of amino acids such as tyrosine, cystine,
leucine and isoleucine, in particular at physiological pH. This work
sought to investigate highly soluble and bioavailable derivatives of
leucine and isoleucine that are applicable for fed-batch processes.
N-lactoyl-leucine and N-lactoyl-isoleucine sodium salts were tested in
cell culture media and proved to be beneficial to increase the overall
solubility of cell culture media formulations. These modified amino
acids proved to be bioavailable for various Chinese hamster ovary (CHO)
cells and were suitable for replacement of canonical amino acids in cell
culture feeds. The quality of the final recombinant protein was studied
in bioprocesses using the derivatives, and the mechanism of cleavage was
investigated in CHO cells. Altogether, both N-lactoyl amino acids
represent an advantageous alternative to canonical amino acids to
develop highly concentrated cell culture media formulations to support
next generation bioprocesses.