Effects of Inhibiting Two Cell Cycle Modulating micrornas
Upper panels: Cells were plated 24 hours after LNA electroporation for the in situ IgG Secretion Assay4. Detection was performed 48 hrs after electroporation. High IgG secretion cutoff is 90th percen...
Nan Lin1, Ken Heuermann,2, Jessica Schlueter,2, Carol Kreader, Scott Knight,2 and Kevin Kayser1
1. Cell Engineering, SAFC, Sigma-Aldrich, 2909 Laclede Ave., Saint Louis, MO 63103, U.S.A. 2. Research Biotechnology, Sigma-Aldrich, 2909 Laclede Ave., Saint Louis, MO 63103, U.S.A.
Keywords: Gene expression, Transduction
In pharmaceutical manufacturing, viral contamination can pose a significant risk to patient safety and damage a company’s reputation. Processes that reduce the risk of viral contamination, such as Hi...
Aaron Mack, Daiva Dailide, Chas Hernandez, Erik Klahn, and Bruce Lehr
Sigma-Aldrich Corporation, Cell Sciences and Development, 2909 Laclede Ave., St. Louis, MO, 63103
Keywords: Amino acid analysis, Cell culture, Culture media, Degradations, Elemental analysis, High performance liquid chromatography, Inductively coupled plasma, Infrared spectroscopy, Mass spectrometry, Pharmaceutical, Precipitation, Reductions, Spectroscopy, Titrations, Vitamins
Identification of the Putative Rosa26 Locus
The biopharmaceutical industry has expressed considerable interest in targeted integration in CHO cells for therapeutic r-protein production applications. In previous studies we have used ZFN’s for s...
Scott Bahr, Nan Lin, Trissa Borgschulte, Jeanne Brooks, Henry George and Kevin Kayser
Cell Sciences and Development, SAFC/Sigma-Aldrich, St Louis, MO 63103 USA
Keywords: Cloning, Gene expression, Polymerase chain reaction, Sequencing
Improving Product Safety Profiles
Post-translational modifications have been shown to affect the bioactivity, clearance rates, immunogenicity and safety profiles of therapeutic glycoproteins. For example anti- N-glycolylneuraminic ac...
Mascarenhas, J., Achtien, K., Richardson, S., Sealover, N., Kaiser, J., Borgschulte, T., George, H., Kayser, K. and Lin, N
Cell Sciences and Development, SAFC Sigma Aldrich2909 Laclede Avenue, Saint Louis, MO 63103, USA
Keywords: Cell culture, Clinical, Eliminations, Gene expression, Glycosylations, High performance liquid chromatography, Mass spectrometry, Sequencing, Size-exclusion chromatography
The Glutamine Synthetase (GS) expression system does not typically require multiple rounds of amplification to isolate high-producing clones (Brown, 1992). However, most Chinese Hamster Ovary (CHO) c...
Kate Achtien, Trissa Borgschulte, Nan Lin, Henry George, Kevin J. Kayser
Cell Sciences and Development, SAFC, Sigma-Aldrich, 2909 Laclede Avenue, Saint Louis, MO 63103, USA
Keywords: Amplification, Cloning, Gene expression, Indicators, Polymerase chain reaction, Polymerase chain reaction - quantitative
Mgat1-Disrupted Chinese Hamster Ovary (CHO) Cells
MGAT1 adds N-acetylglucosamine to the Man5GlcNAc2 (Man5) structure. Goh et al. reported increased sialylation after restoring MGAT1 function in MGAT1 deficient CHO cells. The hypothesis is that Mgat1...
Nan Lin, Dustin Davis, Natalie R. Sealover, Joaquina Mascarenhas, Henry J. George and Kevin J. Kayser
Cell Sciences and Development, SAFC/Sigma-Aldrich 2909 Laclede Ave., Saint Louis, MO 63103. U.S.A.
Keywords: Affinity chromatography, Chromatography, Gene expression, Polymerase chain reaction, Protein extraction
Overexpression of Serpinb1
We report the discovery and validation of a novel CHO cell engineering target (Serpinb1) that has significant effects in enhancing recombinant IgG productivity. We performed transcriptomic studies us...
Nan Lin, Jeanne Brooks, Natalie Sealover, Christopher Limmex, Henry J. George and Kevin J. Kayser
Cell Sciences and Development, SAFC/Sigma-Aldrich, 2909 Laclede Ave., Saint Louis, MO 63103 USA
Keywords: Gene expression, High performance liquid chromatography, Inflammation, Microarray Analysis, Transcription, Transduction, Transfection, cDNA microarrays
Select Housekeeping Genes in Chinese Hamster Ovary Cells
In the present study, we have identified species-specific housekeeping genes (HKGs) for Chinese HamsterOvary (CHO) cells using data from microarray gene expression profiling. HKGs suitable for quanti...
Scott M. Bahr, Trissa Borgschulte, Kevin J. Kayser, Matthew V. Caple and Nan Lin
Cell Sciences and Development, SAFC Biosciences 2909 Laclede Avenue, Saint Louis, MO 63103, USA
Keywords: Amplification, Cell culture, DNA microarrays, Gas chromatography, Gene expression, Melting, Microarray Analysis, Nucleic acid hybridization, Polymerase chain reaction, Transcription
Signal Peptide Optimization
A signal peptide is a 5-30 amino acid (aa) peptide present at the N-terminus of secretory proteins. Signal peptides are known to have a strong impact on both the efficiency of protein secretion and c...
Joaquina Mascarenhas, Dustin Davis, Pegah Jalili, Trissa Borgschulte, Kevin Ray, Henry J. George, Kevin J. Kayser and Nan Lin
Cell Sciences and Development, SAFC/Sigma-Aldrich, 2909 Laclede Ave., Saint Louis, MO 63103. U.S.A.
Keywords: Atomic absorption spectroscopy, Cell culture, Gene expression, High performance liquid chromatography, Mass spectrometry, Size-exclusion chromatography, Transfection
Zinc Finger Nuclease Efficiency
Zinc Finger Nuclease (ZFN) technology has provided researchers with a tool for integrating exogenous sequences into most cell lines or genomes in a precise manner. Using current methods, the efficien...
Scott Bahr, Laura Cortner, Sara Ladley, Trissa Borgschulte, CHOZN® Platform Development Team
SAFC/Sigma-Aldrich, St Louis, MO 63103 USA, email@example.com
Keywords: Gene expression, Recombination, Sequencing
For the majority of manipulations using cell cultures, such as transfections, cell fusion techniques, cryopreservation and subculture routines it is necessary to quantify the number of cells prior to...
Cook Book Sept 2010 Volume 12
Keywords: Carcinogens, Cryopreservation
Cryopreservation of Cell Lines
The protocol below describes the use of passive methods involving an electric -80°C freezer for the cryopreservation of cell cultures. ECACC routinely use a programmable rate controlled freezer. This...
Cook Book Volume 12
Keywords: Cell culture, Cryopreservation, Phase transitions
Resuscitation of Frozen Cell Lines
Many cultures obtained from a culture collection, such as ECACC, will arrive frozen and in order to use the cells they must be thawed and put into culture. It is vital to thaw cells correctly in orde...
Fundamental Techniques in Cell Culture Laboratory Handbook - 2nd Edition
Keywords: Centrifugation, PAGE
Subculture of Adherent Cell Lines
Adherent cell lines will grow in vitro until they have covered the surface area available or the medium is depleted of nutrients. At this point the cell lines should be sub cultured in order to preve...
Cook Book Sept 2010 Volume 12, Fundamental Techniques in Cell Culture Laboratory Handbook-2nd Edition
Subculture of Semi-Adherent Cell Lines
Some cultures grow as a mixed population (e.g. B95-8 - marmoset) where a proportion of cells do not attach to the tissue culture fl ask and remain in suspension. Therefore to maintain this heterogene...
Cook Book Sept 2010 Volume 12
Keywords: Cell culture
Subculture of Suspension Cell Lines
In general terms cultures derived from blood (e.g. lymphocytes) grow in suspension. Cells may grow as single cells or in clumps (e.g. EBV transformed lymphoblastoid cell lines). For these types of ce...
Cook Book Sept 2010 Volume 12
Keywords: Centrifugation, Growth factors
Testing for Mycoplasma by Indirect DNA Stain
DNA staining methods such as indirect Hoechst staining techniques are quick with results available within 72 hours which compares favourably with 4 weeks for detection by culture. Staining of culture...
Cook Book Volume 12
Keywords: Cell culture, Detection methods, Evaporation, Indicators, Polymerase chain reaction
L-Glutamine in Cell Culture
Importance and uses of glutamine in serum-free eucaryotic, including hybridoma and Chinese Hamster Ovary (CHO) cell, cultures
Keywords: Alternative energy, Cell culture, Culture media, Deaminations, Metabolism, Oxidations, Transaminations, Vitamins