https://www.cell.com/trends/microbiology/pdf/S0966-842X(08)00267-9.pdf

The rpoB gene as a tool for clinical microbiologists.

The work on human embryonic stem cells is being performed with
a variety of cell lines using a variety of culture conditions;
a situation that makes standardisation between projects and
publications very difficult. Clearly the consequence of using
such cells would be wasted time and resources but, more
seriously, the generation of erroneous data in the literature
which could both confuse and delay scientific progress in this
area. This guidance document represents the outcome of the
first meeting of the group named The International Stem Cell
Banking Initiative held in October 2007. The document has been
prepared from the perspective of hESC culture but, in many
respects, is broadly applicable to all human stem cell lines
including induced pluripotent stem cell lines.

Consensus Guidance for Banking and Supply of Human Embryonic Stem Cell Lines for Research Purposes

RNA polymerase beta subunit (rpoB) gene and the 16S-23S rRNA intergenic transcribed spacer region (ITS) as complementary molecular markers in addition to the 16S rRNA gene for phylogenetic analysis and identification of the species of the family Mycoplasmataceae.

We summarize here the recent progress in fluorescence-based bioassays for the detection and evaluation of food materials by focusing on fluorescent dyes used in bioassays and applications of these assays for food safety, quality and efficacy. Fluorescent dyes have been used in various bioassays, such as biosensing, cell assay, energy transfer-based assay, probing, protein/immunological assay and microarray/biochip assay. Among the arrays used in microarray/biochip assay, fluorescence-based microarrays/biochips, such as antibody/protein microarrays, bead/suspension arrays, capillary/sensor arrays, DNA microarrays/polymerase chain reaction (PCR)-based arrays, glycan/lectin arrays, immunoassay/enzyme-linked immunosorbent assay (ELISA)-based arrays, microfluidic chips and tissue arrays, have been developed and used for the assessment of allergy/poisoning/toxicity, contamination and efficacy/mechanism, and quality control/safety. DNA microarray assays have been used widely for food safety and quality as well as searches for active components. DNA microarray-based gene expression profiling may be useful for such purposes due to its advantages in the evaluation of pathway-based intracellular signaling in response to food materials.

https://www.mdpi.com/1424-8220/15/10/25831/pdf

Fluorescence-Based Bioassays for the Detection and Evaluation of Food Materials

http://www.protocol-online.org/forums/uploads/monthly_08_2012/msg-6644-0-70048400-1345974406.ipb

Mycoplasma testing of cell substrates and biologics: Review of alternative non-microbiological techniques.

Genetic analysis of housekeeping genes of members of the genus Acholeplasma: phylogeny and complementary molecular markers to the 16S rRNA gene.

In this study, we describe our results on the evaluation of the ability of different permissive mammalian cell lines to support the biological enrichment of mycoplasma species known to be bacterial contaminants of cell substrates. The study showed that this approach is able to significantly improve the efficiency of mycoplasma detection based on nucleic acid testing or biochemical technologies (e.g., MycoAlert mycoplasma detection). Of 10 different cell lines (Vero, MDBK, HEK-293, Hep-G2, CV-1, EBTr, WI-38, R9ab, MDCK, and High Five) used in the study, only MDCK cell culture was found to support the efficient growth of all the tested mycoplasmas (Mycoplasma arginini, M. bovis, M. fermentans, M. gallinaceum, M. gallisepticum, M. synoviae, M. hominis, M. hyorhinis, M. orale, M. salivarium, and Acholeplasma laidlawii) known to be most frequently associated with contamination of cell substrates and cell lines in research laboratories or manufacturing facilities. The infection of MDCK cells with serial dilutions of each mycoplasma species demonstrated that these common cell line contaminants can be detected reliably after 7-day enrichment in MDCK cell culture at contamination levels of 0.05 to 0.25 CFU/ml. The High Five insect cell line was also found to be able to support the efficient growth of most mycoplasma species tested, except for M. hyorhinis strain DBS1050. However, mycoplasma growth in insect cell culture was demonstrated to be temperature dependent, and the most efficient growth was observed when the incubation temperature was increased from 28°C to between 35 and 37°C. We believe that this type of mycoplasma enrichment is one of the most promising approaches for improving the purity and safety testing of cell substrates and other cell-derived biologics and pharmaceuticals.

Biological Enrichment of Mycoplasma Agents by Cocultivation with Permissive Cell Cultures

Herein, we present data demonstrating that the application of initial cell culture enrichment could significantly improve mycoplasma testing methods based on the nucleic acid amplification technology (NAT) including a polymerase chain reaction (PCR)/microarray method. The results of the study using Vero cells demonstrated that this cell culture is able (1) to support efficient growth of mycoplasmas of primary interest, i.e., species found to be cell line contaminants, (2) to increase the sensitivity of NAT assay to the detection limits of the conventional broth/agar culture methods, and (3) to reduce the time required for mycoplasma testing fourfold in comparison with the conventional methods. Detection and identification of mycoplasmal agents were conducted using a modified PCR/microarray assay based on genetic differences among Mollicutes in the 16S-23S rRNA intergenic transcribed spacer (ITS). The application of nano-gold/silver enhancement technology instead of previously used fluorescent dyes significantly simplified the readout of microarray results and allowed us to avoid using expensive scanning equipment. This modification has the potential to expand the implementation of microarray techniques into laboratories involved in diagnostic testing of mycoplasma contamination in cell substrates and potentially in other biological and pharmaceutical products.

Application of Cell Culture Enrichment for Improving the Sensitivity of Mycoplasma Detection Methods Based on Nucleic Acid Amplification Technology (NAT)

Hyesuk Kong

Papers

Genetic analysis of housekeeping genes of members of the genus Acholeplasma: phylogeny and complementary molecular markers to the 16S rRNA gene.

Biological Enrichment of Mycoplasma Agents by Cocultivation with Permissive Cell Cultures

Application of Cell Culture Enrichment for Improving the Sensitivity of Mycoplasma Detection Methods Based on Nucleic Acid Amplification Technology (NAT)