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Abstract

In this publication different detachment factors were tested for enhancing carrier to carrier transfer for scale-up of macroporous microcarrier based bioprocesses. Two Chinese hamster ovary cell lines, CHO-K1 and a genetically engineered CHO-K1 derived cell line (CHO-MPS), producing recombinant human Arylsulfatase B, were examined. The cells were grown on Cytoline 1microcarriers (Amersham Biosciences, Uppsala, Sweden) in protein-free and chemically defined medium respectively. Fully colonised microcarriers were used at passage ratios of approximately 1:10 for carrier to carrier transfer experiments. To accelerate the colonisation of the non-colonised, freshly added microcarriers the detachment reagents trypsin, papain, Accutasetrade mark (PAA, Linz, Austria), heparin and dextransulphate were used. Both cell lines showed good results with trypsin, Accutase and dextransulphate (Amersham Biosciences, Uppsala, Sweden), while papain failed to enhance carrier to carrier transfer in comparison to the non-treated reference. The maximum growth rate of cells on microcarriers with 2% dextransulphate in the medium was 0.25 +/- 0.02d(-1) and 0.27 +/- 0.03d(-1) for the CHO-MPS and CHO-K1, respectively. TheCHO-K1 grew best after detachment with trypsin (mu = 0.36 +/- 0.03d(-1)). This indicates, that one of the key parameters for carrier to carrier transfer is the uniform distribution of cells on the individual carriers during the initial phase. When this distribution can be improved, growth rate increases, resulting in a faster and more stable process.

Development of PCL-PEG nanofibrous mats as alternative carriers for recombinant Chinese hamster ovary cells

“…Microcarriers have been developed to grow anchorage-dependent cell lines, such as CHO cells in bioreactors [8,9] . For the mass production of recombinant proteins, it is proposed that high density culture of mammalian cells should be developed [7] .…”

“…Commercially available microcarriers have been made from a variety of materials, such as DEAE Sephadex, polyester, cellulose, glass and gelatin. The main criteria for a suitable carrier are high porosity, proper hydrophilicity, biocompatibility and biodegradability [8] . If a carrier is to be used in a bioreactor, then its resistance to shear stress and temperature, reusability and durability are essential and of vital importance.…”

Are genetic drift and stem cell adherence in laboratory culture issues for cultivated meat production?

“…Cultured cells must be separated from microcarriers through the use of enzymes such as trypsin–EDTA, the microcarrier degradation or cleavage ( 108 ). This process can be complex, time-consuming and affecting the cell production efficiency ( 109 ).…”

Enhancement and optimization of plasmid expression in femtosecond optical transfection

“…Yet, this would be a crucial step towards lab-on-achip microfluidic devices that have the capacity to both flow and transfect single cells. In contrast to cells in suspension, recently trypsinised cells undergo a prolonged lag phase before entering the growth cycle, resulting in lower transfection efficiency [15,18,19]. This difficulty is highlighted in Figure 5.…”