Validation of an automated blood culture system for sterility testing of cell therapy products DIDIER HOCQUET 1,2 , MARLÈNE SAUGET 1,2 , SANDRINE ROUSSEL 2,3 , CAROLINE MALUGANI 5 , FABIENNE POUTHIER 4,5 , PASCAL MOREL 4,5 , HOUSSEIN GBAGUIDI-HAORE 1,2 , XAVIER BERTRAND 1,2 & FR  ED  ERIC GRENOUILLET 2,3 1 Service d’Hygiène Hospitalière, 2 UMR 6249 Chrono-environnement and 3 Service de Parasitologie-Mycologie, Centre Hospitalier Universitaire R egional Besançon, Besançon, France, 4 UMR 1098 Interaction Hôte-Greffon-Tumeur et Ing  enierie Cellulaire et G enique, Universit  e de Franche-Comt  e, Besançon, France, and 5 Etablissement Français du Sang, Besançon, France Abstract Background aims. Automated blood culture systems are widely used for the detection of microorganisms in cell therapy products. However, they are not validated by the manufacturers for this purpose. The aim of this study was to assess the ability of the Bactec system (Becton-Dickinson, Le Pont-De-Claix, France) to detect the microorganisms that could contaminate cell therapy products. Methods. Three types of vials and conditions were tested: Plus Aerobic/F and Anaerobic/F media incubated at 35  C and Mycosis IC/F medium incubated at 30  C. All vials were incubated 10 days. We tested 18 microorganisms, including slow growers and some with fastidious nutritional requirements (10 bacteria, four yeasts, four filamentous fungi), each with four inocula (10e10 4 colony-forming units) performed in quintuplicate. Results. The com- bination of Plus Aerobic/F and Plus Anaerobic/F vials detected all the tested pathogenic bacteria, all the tested Gram-positive skin commensal or environmental bacteria, all the tested yeasts, and three of four tested filamentous fungi. The addition of the Mycosis IC/F vial extended the range of detected microorganisms to one fungal environmental contaminant. Two bacterial environmental contaminants were not detected by our method. Low inocula of the skin contaminant Propionibacterium acnes were detected only after 7 days of incubation. Conclusions. These data suggest that (i) the prolongation of the incubation time of Plus Aerobic/F and Plus Anaerobic/F vials from 7 to 10 days and (ii) the use of Mycosis IC/F medium make minor contributions in the sterility testing of cell therapy products. We have validated the Bactec method using aerobic and anaerobic vials incubated 7 days at 35  C. Key Words: automated blood culture systems, cell therapy product, microbial contamination, sterility testing Introduction Bacterial contamination of cell therapy products is a potential source of morbidity and mortality in re- cipients. Possible sources of contamination include asymptomatic bacteremia of the donor at the time of collection and improper execution of aseptic tech- nique during collection or processing. In France, cell therapy products are regulated by the National Agency for Medicines and Health Product Safety (ANSM), which emphasizes the importance of manufacturing products in a manner that prevents disease transmission and requires validated methods for testing products. The ANSM performs a nationwide survey of microbial contamination of cell therapy products annually. In 2011, this survey showed that among 17,578 cell products validated for distribution, 16 were contaminated with micro- organisms. This rate increased to 15.4% depending on the type of cell products and the center (1e3). However, clinical sequelae after infusion of progen- itor cells contaminated with bacteria are extremely rare (1e5), in part because of antimicrobial pro- phylactic regimens received by hematopoietic cell transplantation recipients (6). The European Pharmacopoeia, in monograph 2.6.27, recommends methods based on cultures that detect bacteria and fungi without prescribing a specific method (7). Most clinical laboratories are Correspondence: Dr Didier Hocquet, Service d’Hygiène Hospitalière, Centre Hospitalier R egional Universitaire Besançon, 3 boulevard Fleming, 25030 Besançon, Cedex, France. E-mail: dhocquet@chu-besancon.fr Cytotherapy, 2014; 16: 692e698 (Received 5 March 2013; accepted 17 September 2013) ISSN 1465-3249 Copyright Ó 2014, International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jcyt.2013.09.005