2013 Collection

Viral Vector Production in the Integrity® iCELLis® Disposable Fixed-bed Bioreactor from Bench-scale to Industrial Scale

Recombinant viruses (e.g. lentivirus and adeno-associated-virus) can be used as human gene therapy vectors. They are mainly produced in adherent cell cultures (e.g. HEK293T, A549, VERO) in Roller Bottles or multiple-tray-stacks using either transient transfection or infection strategies. Therefore, the Integrity® iCELLis® (ATMI LifeSciences) line of bioreactors offers a new production alternative with stronger process controls and ease of scale-up.   The iCELLis bioreactor is designed for adherent cell culture applications. Cells grow on microfibers carriers packed in a fixed-bed…

Is the Gold Standard Tarnished? Weaknesses in the Standard Method Compromise Your RMM Validation

Introduction of a new Rapid Microbial Method (RMM) requires a full validation. The purpose of the validation is to prove that equivalent or better results are obtained using the new method when compared to the compendia. One assumes that the result obtained with the compendial method is absolute and is the “Gold Standard” by which to compare the new test. In reality, the compendial method exhibits a number of weaknesses that compromise the integrity of the validation. The standard requires…

Cookie Cutter Proteolysis: Achieving Reproducible, Efficient Digestions for Proteomic Workflows

Cookie Cutter Proteolysis: Achieving Reproducible, Efficient Digestions for Proteomic Workflows   Protein sample preparation workflows for mass spectrometric analysis that involve proteolysis are often labor-intensive, time consuming and user dependent. These workflows often involve digestion, solid phase extraction, drying, and re-suspension prior to reversed phase separation into the mass spectrometer. The introduction of variability at many of these steps hinders discovery initiatives as well as the ability to convert these discoveries into viable assays.   Recently, an automated protein digestion…

Maximizing Protein Expression in CHO Suspension Cells Through Transient Transfection

Transient transfection in mammalian cell lines provides an avenue for researchers to bridge the development bottleneck and shorten the time to usable protein. The method also maintains post translational modifications crucial for biotherapeutic function. Chinese Hamster Ovary (CHO) suspension cells are especially suited for high yield production of recombinant proteins, despite being refractory to commonly used transfection methods (e.g. 25kDa linear PEI). Mirus Bio has developed a more effective alternative, the TransIT-PRO® Transfection Kit. Transfection efficiencies are affected by many…

T Cells Expanded in the WAVE Bioreactor™ 2/10 System Maintain a Healthy Phenotype

T cell immunotherapy often requires the expansion of a small select starting population in vitro. To achieve therapeutic doses, this population is required to undergo multiple and rapid rounds of replication. Rapid T cell expansion raises the possibility of inducing senescence or an aged phenotype, both of which are detrimental to the recipient patient. The WAVE BioreactorTM System is often used for the final expansion phase before patient infusion and we have analysed the aging characteristics of T cells that…

Transfer of Hepatic Progenitor Stem Cell Culture Process from Multitray Stacks to the Integrity® Xpansion™ Multiplate Bioreactor

Scale-up a stem cell process may be challenging: small variations in physicochemical parameters (surface characteristics, pH and dissolved oxygen) can heavily impact stem cell growth and behavior. The Integrity® Xpansion™ multiplate bioreactors have been designed to enable an easy transfer from multiple-tray stacks process by offering the same cell growth environment: stacked hydrophylized polystyrene plates in a compact and closed system (from 10 to 200 plates per bioreactor equivalent respectively to 6120cm² and 122400cm²). As there is no headspace between…

Bio-Simplex™ Single-Use, Aseptic PreCulture Systems

The growth and aseptic transfer of a microbial pre-culture from seed vial to bioreactor is a critical process step in the production of BioPharmaceuticals. The pre-culture step is performed in a biological safety cabinet or laminar flow hood, which adds time and significant cost and to the process. Saint-Gobain Bio-Simplex™ Single-Use Pre-culture Systems provide a sterile environment for cell culture and aseptic transfer of all fluids in and out of each cell culture vessel.

Characterization of a Biomanufacturing Fermentation Process Using a New DOE Approach: Definitive Screening Designs

Traditionally, a bioprocess is characterized using a two-step approach involving factor screening designs followed by response surface designs. This approach is very costly and time consuming since it requires a significant number of runs. Recently, Jones and Nachtscheim (2011) described a more efficient design that allows for factor screening, resolution of two-way interactions as well as estimation of quadratic effects in a single-step. The design, termed Definitive Screening has not yet been validated on a bioprocess. Here, traditional and Definitive…

Comparison of Commercial Kits for Extraction of Residual Host Cell DNA

Expression of therapeutic proteins in cultured cells is a cost effective method for production of commercial quantities of a drug substance. However, the manufacturing and purification process of these products leaves the potential for DNA contamination from the host cells. Due to the theoretical potential for the transfer of oncogenes from the host cell, the WHO has set a residual host cell DNA limit of 10ng/dose in biologic therapeutics. Regulatory agencies have set allowable limits between 100pg/dose and 10ng/dose depending…

Culture of Normal Human Dermal Fibroblast Cells in a Functionally Closed Automated Cell Expansion System

The Quantum Cell Expansion System is a functionally closed and automated hollow-fiber bioreactor system that is designed to expand both adherent and suspension cells in a reproducible manner. The hollow-fiber membrane requires a coating agent to help facilitate cellular adherence when culturing an adherent cell type such as MSCs. Pooled human cryoprecipitate (CPPT, Bonfils Blood Center) was examined as an alternative to FN because it is a rich source of extracellular matrix components, including fibrinogen (Freedman, 2010), and also because…