FibraCel
Disks
FibraCel disks are a proven support system used to
increase yields of suspension and anchorage-dependent cultures. They
can be used in NBS' CelliGen Plus, CelliGen 310 and BioFlo 4500
bioreactors, and are at the heart of our Spinner Basket and new
FibraStage Disposable Cell Culture Sytems. FibraCel is also
available for use in disposable bags, shake flasks and other
bioreactor systems.
Animal cells such as hybridoma, insect and various
anchorage-dependent recombinant cells have all been successfully
grown using FibraCel disks. FibraCel disks are manufactured
according to cGMP guidelines and is composed of polyester non-woven
fiber and polypropylene (Figure 1). FibraCel disks are also treated
electrostatically to facilitate suspension cells adhering to the
disks and becoming trapped in the fiber system, where they remain
throughout the process. The disks are predominately used as a matrix
for the growth of cells when secreted products are desired.
A number of cell lines often have difficulty
attaching to the surface of microcarriers. Cell lines such as MRC5
often require ideal conditions of temperature in order to attach to
the support, frequently resulting in reduced cell viability. MRC5 as
well as most other cell lines (Table 1) attach more readily to flat
surfaces of the FibraCel disk because they become embedded in the
fiber system (Figure 2).
Table 1 - Summary of
cells
successfully used on FibraCel disks
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Hybridoma |
Anchorage-Dependent |
Insect |
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DA4.4
123A
127A
GAMMA
67-9-B |
3T3, COS, Human Osteosarcoma
MRC-5, BHK,
VERO
CHO, rCHO-tPA
rCHO - Hep B Surface Antigen
HEK
293, rHEK 293
rC127 - Hep B Surface Antigen
Normal Human
Fibroblasts
Stroma
Hepatocytes |
Tn-368
SF9
rSF9
Hi-5 |
Cell density and productivity
achieved with cells grown on FibraCel disks can be up to ten times
higher than anchorage-dependent cells growing on microcarriers (or
yields of suspension cultures).
Figure 1 - High resolution micrograph of a
FibraCel disk indicating the polyester mesh with polypropylene
support.
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igure 2 - High resolution micrograph of HEK
293 cells grown on FibraCel at Day 4 of growth
cycle.
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Figure 3 - HEK 293 cells
grown on
FibraCel at Day 7
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CelliGen Plus and Spinner Baskets are
equipped to use FibraCel disks
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Advantages of FibraCel over standard
microcarrier systems
The advantages and benefits of
FibraCel disks over standard microcarrier technology:
- Low pressure drop across the bed.
- Scale-up of cell culture systems generally
requires equalization of pressures over the microcarrier bed and
a examination of the pressure variation effect on viability
throughout the microcarrier bed. However, the low pressure drop
of FibraCel minimizes this variability and maintains a global
viability of cells over the entire bed.
- High surface-to-volume ratios.
- The increased ratio increases the total
biomass that can be maintained in the bioreactor. This coupled
with the greatly enhanced production of cellular products
dramatically increases the efficacy of FibraCel over standard
microcarrier culture.
- Less susceptibility to shear forces from
impeller blades and sparger gas bubbles.
- It is commonly seen in standard microcarrier
culture that the beads are fractured (with concurrent
destruction of culture) due to normal use of impeller blades and
gas inclusion. FibraCel disks maintain their integrity (and
production levels) and cells entrapped are shielded from the
turbulence of impeller rotation and sparged
gases.
- Higher mass transfer of nutrients and
oxygen.
- Analysis of the cells located at the bottom
of the bed indicate that they are as viable as the cells located
at the top due to the uniform mass transfer of nutrients and
oxygen in the FibraCel basket system.
- Easy and efficient separation of biomass
from secreted products.
- FibraCel offers sustained long-term periods
of high-density growth in perfusion, without any danger of
clogging and with elimination of the need for cell filtration to
separate cells from product.
Normally it takes approximately 6 hours for cells
to attach to microcarriers (with a normal inoculum of 1 x 106
cells/mL), whereas cells can attach within 15 ? 60 minutes on
FibraCel disks. Moreover, the growth process for microcarrier
cultures can require extended delays for periodic stoppage of
stirring to allow time for cells to become attached. By comparison,
the FibraCel bed is inoculated (3 x 105 cells/mL) in a single
step.
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Specifications |
Surface Area per gram |
1200 cm2 |
Disk diameter |
6 mm |
Required inoculum |
3 x 105 cells/mL final
volume |
Endotoxin tested |
Yes |
Bioburden tested |
Yes |
Cytotoxicity tested |
Yes |
Autoclavable |
Yes |
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Product
No.
|
Disk
Quantity
(grams) |
Total Surface Area
(cm2) |
|
M1176-9984 |
50 |
6 x
104 |
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M1292-9988 |
250 |
3 x
105 |
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M1176-9984BS* |
50 |
6 x
104 |
*Sold
only in Europe |
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Guidelines for the Use of FibraCel
Disks
in the CelliGen 310 and CelliGen Plus
Vessels |
Vessel
Size |
Minimum
Quantity |
Typical
Quantity Used |
Maximum
Quantity |
2.2 L |
25 |
50 |
70 |
5.0 L |
50 |
150 |
170 |
7.5 L |
100 |
250 |
270 |
14 L |
150 |
500 |
550 |
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