pConPlus谷氨酰胺加压筛选工业级悬浮细胞大量表达载体 BioVector NTCC质粒载体菌种细胞基因保藏中心

pConPlus谷氨酰胺加压筛选工业级悬浮细胞大量表达载体 BioVector NTCC质粒载体菌种细胞基因保藏中心 — pConPlus vectors
— Serum-free medium system
— Protein-free media systems
— Host Cell Protein Western Blotting Assays
— Host Cell Protein ELISA Assays
GS System™ uses a robust viral
promoter and selection via glutamine metabolism to provide
extremely rapid development of high-yielding, stable,
cGMP-compatible mammalian cell lines. The GS System™ is
successfully used by over 85 global pharmaceutical and biotechnology
companies and is familiar to all worldwide regulatory
authorities who have already approved 5 licensed products
which use the GS System™ including Zenapax® (Roche)
and Synagis® (Medimmune).
The international use of the GS System™ by both commercial
organisations and academic institutions has lead to a large
body of published information. New users can draw upon
this material to expand their knowledge and skill base and
improve their use of the GS System™.
Lonza has itself created over 250 cell lines using the GS System
™, many of which have been grown at large-scale and produced
product for use in clinical trials and in-market supply.
Other GS System™ users have also accumulated experience
with a diverse range of products where high yields have been
achieved. Many investigators use the GS System™, not only
to develop a manufacturing process, but as a tool to create
recombinant proteins for biological studies. The reliability of
the GS System™, as a consistent means of rapidly generating
high-producing cell lines, speeds time to market.
Principles of the GS System TM
Glutamine synthetase (GS) is the enzyme responsible for
the biosynthesis of glutamine from glutamate and ammonia.
This enzymatic reaction provides the only pathway for glutamine
formation in a mammalian cell.
In the absence of glutamine
in the growth medium, the
GS enzyme is essential for
the survival of mammalian
cells in culture. Some mammalian
cell lines, such as
mouse myeloma lines, do
not express sufficient GS to
survive without added glutamine. With these cell lines, a transfected
GS gene can function as a selectable marker by permitting
growth in a glutamine-free medium. Other cell lines, such
as Chinese hamster ovary (CHO) cell lines, express sufficient
GS to survive without exogenous glutamine. In these cases,
the GS inhibitor, methionine sulphoximine (MSX), can be used
to inhibit endogenous GS activity such that only transfectants
with additional GS activity can survive.
Yield The high manufacturing cost of protein products,
particularly for therapeutic proteins, means that maximising
volumetric productivity is essential if economic processes
are to be established. Use of the GS System™ reliably results
in high yielding cell lines early in cell construction programmes.
Maximum expression levels attainable depend on
the product but cell lines producing over 5 g/L of recombinant
antibody have been created, with specific production
rates in the range of 15-65 pg/cell/day.
Speed Speed at the development stage of any biotechnology
project is crucial to success. The GS System™ allows
for rapid selection of high yielding cell lines during the first
screen. Even higher yields are achieved through media and
process optimization. This significantly reduces the time required
to generate a cell line suitable for cGMP manufacture.
Construction of full length antibodies with human constant
regions is rapid and easy using Lonza’s GS constant region
vectors which enable the addition of any variable region in a
single ligation step.
Lonza’s proprietary CHOK1SV host cell line facilitates the
adaptation to protein-free suspension culture compared to
standard CHOK1 processes.
Standard GS Package
The current standard package of GS materials to which the
user has access with a GS REA are:
— GS vectors and sequence data
— Vials of GMP host cell bank NS0
— Vials of GMP host cell bank CHOK1SV
— Transfection medium system
— Comprehensive technical operating manuals
— Cell bank characterization reports to support regulatory
submissions
— Access to technical support from Lonza’s GS experts
— GS newsletters
— Technology updates
Optional GS Packages
GS customers can augment their standard GS REA package
to purchase other proprietary components together with
associated know-how. The current optional packages of GS
materials to which the user has access are:
— pConPlus vectors
— Serum-free medium system
— Protein-free media systems
— Host Cell Protein Western Blotting Assays
— Host Cell Protein ELISA Assays
BioVector NTCC质粒载体菌种细胞蛋白抗体基因保藏中心
电话：+86-010-53513060
网址：www.biovector.net [Supplier来源] http://www.biovector.net