Date of Award
5-2026
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Bioengineering
Committee Chair/Advisor
Sarah W. Harcum
Committee Member
Vishal Thomas
Committee Member
Agneta Simionescu
Abstract
Biopharmaceuticals are medicines produced in cells which are used to treat diseases such as cancer. Monoclonal antibodies (mAbs) represent the majority of approved biotherapeutics. MAbs are mostly produce using Chinese hamster ovary (CHO) cells. CHO cells are favored for resiliency, scalability, and established safety, and are considered the “workhorse” organism for biopharmaceuticals. Amino acids are a key component of cell culture media, however several amino acids have solubility limits, such as cysteine, cystine, and tyrosine. At neutral pH, these amino acids are poorly soluble. However, dipeptides, such as N,N'-di-L-Alanyl-L-Cystine (ACCA) have been reported to increase cysteine and cystine availability. Further, Glycyl-L-Tyrosine (GY) has been reported to increase tyrosine availability. The objective of this study was to evaluate the effects of dipeptide combinations in cell culture media to replace cysteine, cystine, and tyrosine. Initially, N’-di-L-Lysyl-L-Cystine dihydrochloride (KCCK) and GY were investigated to determine if the high pH feed containing these amino acids could be eliminated. Next, two dipeptides for each of the cysteine, cystine, and tyrosine replacements were investigated (e.g., KCCK versus ACCA, and GY versus L-Alanyl-L-Tyrosine dihydrate (AY)). In addition to cell growth and titers, critical quality attributes (CQA) were assessed, i.e., charge variants and glycosylation. It was determined that the dipeptide additions increased operational simplicity, without negative CQA or cell growth.
Recommended Citation
Herman, Louise C., "The Impact of Dipeptides on Product Quality in Chinese Hamster Ovary Cells" (2026). All Theses. 4745.
https://open.clemson.edu/all_theses/4745