RT Journal Article
T1 Technical challenges for complete implementation of automated growth-based methods for microbiological examination of advanced therapy medicinal products. What's wrong with Candida albicans?
A1 Rodríguez-Acosta, Antonio
A1 Chaparro-García, Jesús
A1 De-Toro, Inmaculada
A1 Maldonado-Sánchez, Rafael
A1 Muñoz-Fernández, Raquel
A1 Antúnez, Cristina
A1 Frecha, Cecilia
A1 Leyva, Laura
K1 Candida albicans
K1 automated growth-based methods
K1 blood culture system
K1 cell therapy products
K1 method suitability
K1 sterility testing
AB Automated growth-based methods for sterility testing of cell-therapy products should be qualified to demonstrate that they are equivalent to, or better than, the conventional reference method. The aim of the present study was to assess the ability of the BACTEC FX40 system to detect low microbial contamination and to confirm the suitability of the method in the presence of seven different human mesenchymal cell-based products, according to Ph. Eur. 2.6.27. Additionally, a study to select the best vial to detect fungus contamination was performed. Microorganisms representing Gram-negative, Gram-positive, aerobic, anaerobic, spore-forming, slow-growing bacteria, yeast and mold were prepared in either Dulbecco's PBS or seven biological matrices containing approximately 5, 10, and 15 colony-forming units (CFU) per sample. These preparations were inoculated to the specific media required for each test method: (i) BACTEC aerobic and anaerobic vials; (ii) aerobic and anaerobic media for direct inoculation; and (iii) Trypcase soy 3P or Brucella blood agar plates. Colonies from cultures were identified using MALDI-TOF mass spectrometry. The BACTEC FX40 system, in both Dulbecco's PBS and the biological matrices with a 5-CFU inoculum, detected most of the microorganisms significantly faster than the conventional method, despite the presence of a matrix containing gentamicin and several matrices containing 10% DMSO. Conversely, it showed an extremely delayed detection of Candida albicans compared with the conventional method. The addition of a Mycosis IC/F (MYC) vial decreased radically the time to detection (TTD) of C. albicans (28.2 ± 1.8 h) compared with the conventional method (36 h). When a MYC vial was added to the standard aerobic and anaerobic vials to test each sample, BACTEC FX40 was shown to be a superior alternative sterility method for cell-therapy products contaminated with low inocula, with a faster TTD for microbial growth compared with the conventional method (5 versus 14 days). The studies were carried out in different cell-based matrices with sensitivities and specificities of 100% for all the tested strains at 15-, 10- and 5-CFU inoculum, with the exception of Kocuria rhizophila at 5 CFU (90.48% sensitivity and 100% specificity).
YR 2022
FD 2022-01-13
LK http://hdl.handle.net/10668/22298
UL http://hdl.handle.net/10668/22298
LA en
DS RISalud
RD Apr 19, 2025