YAMATO Masayuki
   Department   Research Institutes and Facilities, Research Institutes and Facilities
   Position   Professor
Article types Other
Language English
Peer review Peer reviewed
Title Lessons learned from contamination with endotoxin originated from the supplement in the cell culture medium.
Journal Formal name:Regenerative therapy
Abbreviation:Regen Ther
ISSN code:23523204/23523204
Domestic / ForeginForegin
Volume, Issue, Page 27,pp.230-233
Author and coauthor UEHARA Koaki†, OSHIRO Eriko, OCHIAI Atsushi, TAKAGI Ryo, YAMATO Masayuki, KATO Atsunaga*
Publication date 2024/12
Summary INTRODUCTION:Endotoxin is a typical pyrogen derived from the outer membrane of Gram-negative bacteria. In fabricating cell-based medicinal products, it is necessary to control endotoxin in the process and the products. In the quality control tests of our clinical study, endotoxin concentration in the culture supernatant of autologous oral mucosal epithelial cell sheets exceeded the criterion value. Therefore, endotoxin measurements were conducted to clarify the cause of the endotoxin contamination.METHODS:The reagents used to prepare the culture medium, the unused culture medium, and the culture supernatants were diluted with pure water. Endotoxin concentrations in the diluted samples were measured.RESULTS:Endotoxin was detected in both the unused culture medium and the culture supernatant of the epithelial cell sheets at higher concentrations than the criterion value. Therefore, endotoxin concentrations in the reagents used to prepare the culture medium were measured and were found to be below the criterion value, except for cholera toxin. On the other hand, three lots of cholera toxin products were used for the measurement, and the endotoxin concentrations were higher than the criterion value. The results indicate that the endotoxin contamination is caused by the cholera toxin product.CONCLUSIONS:To prevent endotoxin contamination in cell-based medicinal products, endotoxin concentrations in reagents used for the fabrication should be measured in the facility conducting clinical research or confirmed by an adequate certificate of analysis from the manufacturers of the reagents.
DOI 10.1016/j.reth.2024.03.022
PMID 38596824