"I have been using FiberCell® Systems cartridges for the production recombinant proteins in CHO cells for five years. I routinely produce a half-gram of protein in two months in a volume of less than five liters. This type of production would not be possible using conventional methods. FiberCell® Systems hollow fiber bioreactors have made an invaluable contribution to my research."--Dr. James Arthos -- Bethesda , Md.
Current methods for the production of secreted biologicals such as recombinant proteins, cytokines and conditioned medium involve the use of inefficient in-vitro culture systems such as roller bottles or large numbers of tissue culture flasks. FiberCell® Systems hollow fiber culture systems facilitate the easy culture of large numbers of cells (1-2 X 1010) replacing roller bottles or hundreds of flasks while concentrating the secreted protein 100X or more.
Secreted proteins can be 100 times more concentrated vs. tissue culture supernatant.
- Reduced serum requirements facilitates purification
- Small harvest volume for easy handling
- No splitting of cells required, cartridge maintenance just 15 minutes a day
- Cultures can be maintained for several months of production
- Optimal cell culture conditions can result in improved protein assembly and folding
 Comparison (See chart left) of a purified recombinant human IgM produced from CHO cells grown in either a 150 cm2 tissue culture flask (upper panel) or a FiberCell® Systems polysulphone cartridge (lower panel). Gel filtration chromatography reveals incomplete polymerization of the IgM produced in the flask. Both a highly polymerized IgM (peak A.) and non-polymerized (peak B.) are observed. In contrast, the same protein produced in a FiberCell® Systems cartridge is expressed almost entirely in highly polymerized form (peak C.) 478 mg of purified protein were produced in 2 months in a volume of less than 5 liters using catalog #2018.
SDS-Page gel of successive harvests from the ECS of a recombinant protein secreted by a 293 cell line. Initial medium is DMEM with 10% FBS (Monday). Medium is changed from DMEM-FBS to Hyclone serum free medium for 293 cells. Note the diminution of serum proteins, especially BSA in the harvest from the ECS while the protein of interest remains constant or increases as the adaptation continues. Protein of interest is higher in concentration on Mondays as it has accumulated over the weekend to a higher level.
 
Production of a hexeramized IgG consisting of 6 IgG1 subunits held together by 3 IgA tails in a CHO cell line. When grown in flask culture (top trace) about 40% of the protein is expressed as an incompletely folded monomeric sub-unit. When the same cells are culture in the FiberCell® Systems hollow fiber bioreactor module more than 90% of the protein is expressed as a properly folded hexamer. This is due to the superior cell culture conditions inside the hollow fiber cartridge. Mediums used was DMEM with 2% FBS. 475 mg of purified protein was produced in FiberCell® Systems catalog number C2018 in a period of 8 weeks in a collected volume of less than 5 liters
The medium 20 kd MWCO FiberCell® Systems cartridge (catalog number C2011) was used to produce 276 mg of protein in a total volume of 900 mL in 2 months using serum-free medium. The cartridge was run over the weekends with a one liter bottle of serum-free medium. This accounts for the extremely high levels of lactate and protein concentration seen on peak days. At it's highest point lactate was 3.8 mg/mL, glucose less than 100 mg/mL and pH below 5.9. Highest protein concentration was 900 µg/mL. Although a certain amount of cell viability was lost the replacement of the medium with a fresh bottle resulted in continued cell growth and protein production. When grown in the FiberCell® Systems hollow fiber bioreactor cells most cell types demonstrate high resistance to lactate resulting in easier management of cell culture medium changes.
Left: 246 mgs of purified recombinant IgG1 from a CHO (DG44) cell line was harvested from the C2011 20kd MWCO cartridge. Medium was a serum free, protein free formulation similar to CDM HD. Each harvest was 19 mls in volume; total harvest volume was 304 mls for an average concentration of over 800 micrograms per day per milliliter. The cartridge consumed 1 liter of medium every two days and the culture was maintained for a total of 35 days. Even though cell viability in the harvest was fairly low the expressed protein was very clean as demonstrated by the gel of the un-purified harvest shown below. Contamination with cellular proteins and DNA was quite low.
| BIOREACTOR |
P3202 |
|
| CARTRIDGES |
Catalog No. |
Size |
Surface Area |
Fiber Type |
Packing Density |
ECS Vol |
MWCO 50% |
Max. Cell# |
|
C2003 |
Large |
1.2 m2 |
low flux PS |
50% |
70 mL |
|
|
more info |
C2008 |
Medium |
3000 cm2 |
low flux PS |
50% |
15 mL |
|
|
more info |
C2011 |
Medium |
3000 cm2 |
high flux PS |
50% |
15 mL |
|
|
more info |
C2018 |
Large |
1.2 m2 |
high flux PS |
50% |
70 mL |
|
|
more info |
| RESERVOIR CAPS |
A1005 |
|
A1006 |
|
| SERUM REPLACEMENT |
| CDM-HD more info |
|
