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Dabrazhynetskaya A.,U.S. Food and Drug Administration | Furtak V.,U.S. Food and Drug Administration | Volokhov D.,U.S. Food and Drug Administration | Beck B.,American Type Culture Collection ATCC | Chizhikov V.,U.S. Food and Drug Administration
Journal of Applied Microbiology | Year: 2014

Aims: The aim of this study was to optimize conditions for preparation and cryopreservation of mycoplasma reference materials suitable to evaluate alternative nucleic acid testing (NAT)-based assays and to compare their limits of detection (LODs) with those of conventional culture-based methods. Methods and Results: Acholeplasma laidlawii, Mycoplasma gallisepticum and Mycoplasma arginini stocks with low ratios of genomic copies to colony forming units (12, 8 and 4, respectively) harvested in early stationary phases of growth were preserved with different cryoprotective agents (CPAs) under slow (1°C min-1), moderate (8°C min-1), fast (13°C min-1) and 'snapshot' (60°C min-1) cooling rates. Depending on mycoplasma species, increasing the cooling rate from slow to snapshot enhanced cell survival up to 5-fold. The addition of 10% (v/v) dimethyl sulfoxide (DMSO) and 15% (v/v) glycerol significantly improved cell survival of all tested strains. Cryoprotected stocks maintained high and stable titres for at least 1 year during storage at -80°C. Sonication of cell cultures prior to cryopreservation enhanced cell dispersion and reduced of GC/CFU ratios. Conclusions: It is feasible to prepare stable reference stocks of cryopreserved mycoplasma cells suitable to reliably compare NAT- and culture-based mycoplasma testing methods. Significance and Impact of the Study: This study describes experimental results demonstrating the preparation and storage of highly viable and dispersed mycoplasma reference stocks suitable for comparing alternative NAT-and conventional culture-based mycoplasma detection methods. © 2013 The Society for Applied Microbiology This article has been contributed to by US Government employees and their work is in the public domain in the USA.

Miranda L.B.,Bluechiip Ltd Bluechiip Ltd. | Miranda L.B.,Biobusiness Consulting Inc | Wyatt K.,American Type Culture Collection ATCC | Johnston I.,Bluechiip Ltd Bluechiip Ltd. | And 2 more authors.
Biopreservation and Biobanking | Year: 2013

Background: Preservation and optimization of biosample integrity to foster relevant research results and outcomes is a guiding principle of sample management. Tracking pre-analytical biospecimen lifecycle variables and bioprocessing chain of custody data enables documentation of adherence to best, regulatory and quality biobanking practices. Knowledge of individual sample and sample set temperature variability is believed to enhance delineation of artifacts during downstream analysis. Analysis of temperature responses may elucidate understanding of temperature trends which can aid downstream interpretation and provide an empirical foundation for "fit for purpose" sample management protocols and evidence-based biobanking practices. Bluechiip and the American Type Culture Collection (ATCC) conducted a pilot to test the bluechiip technology® performance and validate key proofs of concept for tracking temperature of biological samples. Methods: One hundred six (106) Corning® cryovials with bluechiip® buttons and one hundred six (106) standard Corning® cryovials labeled with 1-dimensional (1D) barcoded labels were evaluated. Identifiers were tracked and temperature data recorded in corresponding environments ranging from-192°C to + 57°. Results: Nine of ten proof of concepts, defined in collaboration with ATCC successfully demonstrated functional capabilities of the bluechiip® technology. Bar-code label read performance was compared, producing evidence demonstrating a high rate of failure on the bar-code arm. Conclusion: Temperature data collected heightened observations of sample temperature variability. Prevalence of bar-code label read failure and issues affecting reliability of barcode performance may be under-reported and unrecognized in sample management practice, particularly when the temperatures are lower than-60°C. It appears the bluechiip® tracking technology may offer increased reliability over one-dimensional (1D) bar-coding technology; however while promising these findings require validation in future trials, including twodimensional (2D) bar-coding technologies. © 2013, Mary Ann Liebert, Inc.

Capes-Davis A.,Childrens Medical Research Institute | Reid Y.A.,American Type Culture Collection ATCC | Kline M.C.,U.S. National Institute of Standards and Technology | Storts D.R.,Promega Corporation | And 18 more authors.
International Journal of Cancer | Year: 2013

Continuous human cell lines have been used extensively as models for biomedical research. In working with these cell lines, researchers are often unaware of the risk of cross-contamination and other causes of misidentification. To reduce this risk, there is a pressing need to authenticate cell lines, comparing the sample handled in the laboratory to a previously tested sample. The American Type Culture Collection Standards Development Organization Workgroup ASN-0002 has developed a Standard for human cell line authentication, recommending short tandem repeat (STR) profiling for authentication of human cell lines. However, there are known limitations to the technique when applied to cultured samples, including possible genetic drift with passage. In our study, a dataset of 2,279 STR profiles from four cell banks was used to assess the effectiveness of the match criteria recommended within the Standard. Of these 2,279 STR profiles, 1,157 were grouped into sets of related cell lines - duplicate holdings, legitimately related samples or misidentified cell lines. Eight core STR loci plus amelogenin were used to unequivocally authenticate 98% of these related sets. Two simple match algorithms each clearly discriminated between related and unrelated samples, with separation between related samples at ≥80% match and unrelated samples at <50% match. A small degree of overlap was noted at 50-79% match, mostly from cell lines known to display variable STR profiles. These match criteria are recommended as a simple and effective way to interpret results from STR profiling of human cell lines. Copyright © 2012 UICC.

Motaung T.E.,University of the Free State | Albertyn J.,University of the Free State | Kock J.L.F.,University of the Free State | Lee C.-F.,National Hsinchu University of Education | And 3 more authors.
Antonie van Leeuwenhoek, International Journal of General and Molecular Microbiology | Year: 2013

During a survey of unidentified yeast isolates deposited in the UNESCO-MIRCEN Biotechnological Yeast Culture Collection housed at the Department of Microbial, Biochemical and Food Biotechnology of the University of the Free State, one isolate obtained from soil in South Africa showed 100 % identity in D1/D2 rDNA sequence with undescribed basidiomycetous yeasts isolated from the gut of beetles from the United States of America and forest soil from Taiwan in the NCBI sequence database. Phylogenetic analyses using sequences of the D1/D2 rDNA and ITS regions indicated that all these isolates form a well-supported sub-clade that is the sister clade to the Brassicae plus Porosum clades of Trichosporon in the order Trichosporonales. Subsequent phenotypic tests revealed that asexual reproduction by budding is rare but dominated by arthroconidia resulting from segmentation of hyphae and that fusiform giant cells are characterized by budding from a broad base. These findings further suggest that these isolates belong to a single tremellomycetous yeast species for which the name Trichosporon vanderwaltii CBS 12124T (=NRRL Y-48732T, =UOFS Y-1920T) is proposed. © 2012 Springer Science+Business Media B.V.

Fogli L.K.,New York University | Williams M.E.,University of Virginia | Connors J.M.,British Columbia Cancer Agency | Reid Y.,American Type Culture Collection ATCC | And 2 more authors.
Leukemia and Lymphoma | Year: 2015

Mantle cell lymphoma (MCL) is a rare B-cell malignancy that carries a relatively poor prognosis compared to other forms of non-Hodgkin lymphoma. Standardized preclinical tools are desperately required to hasten the discovery and translation of promising new treatments for MCL. Via an initiative organized through the Mantle Cell Lymphoma Consortium and the Lymphoma Research Foundation, we gathered MCL cell lines from laboratories around the world to create a characterized MCL Cell Bank at the American Type Culture Collection (ATCC). Initiated in 2006, this collection now contains eight cell lines, all of which have been rigorously characterized and are now stored and available for distribution to the general scientific community. We believe the awareness and use of these standardized cell lines will decrease variability between investigators, harmonize international research efforts, improve our understanding of the pathogenesis of the disease and hasten the development of novel treatment strategies. © 2015 Informa UK, Ltd.

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