Cleaning methods for biosafety cabinet to eliminate residual mycoplasmas, viruses, and endotoxins after changeover.

Introduction: Cell-processing operations can potentially contaminate biosafety cabinets, which should be maintained sterile. However, unintended contamination can occur owing to the presence of viruses, mycoplasmas, and bacteria in the raw materials. Moreover, although several methods for expunging these contaminants have been proposed, an optimal method has not yet been determined. Additionally, the effectiveness of conventional methods for eliminating these contaminants remains unclear owing to their unique characteristics and potential resistances to cleaning. Therefore, this paper proposes a risk-based approach to identify appropriate cleaning methods and reduce the likelihood of cross-contamination in biosafety cabinets by these contaminants. Methods: Various cleaning methods for eliminating mycoplasmas, viruses, and endotoxins from biosafety cabinets were evaluated, including ultraviolet (UV) irradiation at 200 mJ/cm Results: UV irradiation and wiping with BKC inhibited the growth of mycoplasma and significant decreased their presence compared with the other cleaning methods. Notably, mycoplasma were detected after wiping all SUS304 plates with ETH, which is a widely used cleaning method. Additionally, the cleaning efficacy for virus showed that the TCID Conclusions: The changeover protocols currently employed in most cell-processing facilities may be ineffective as pathogenic or nonpathogenic materials may remain even after ETH wiping, leading to unintended cross-contamination. To the best of our knowledge, this is the first study to provide reference data of different cleaning methods for mycoplasmas, viruses, and endotoxins in cell-product manufacturing facilities, and can potentially support the development of evidence-based management strategies for ensuring safe cell-product processing.