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Mammalian Cell Expression system is able to perform all of the post translational modifications to the protein. Therefore mammalian cell line is not only used for protein production, but also for immunogen, experiment material and down-stream validation.

Service highlight:
1. Team members have average 10 years’ experience in mammalian expression system.
2. Up to 200L serum-free fermentation system.
3. 90% success rate for protein expression.

Service and Timeline	Service Description	Deliverables	Price
P110411 Mammalian-Ready 4 – 6 Weeks	1. Cell transfection. 2. 80mL cell culture. 3. Expression condition test: up to 2 different conditions. 4. Protein purification (1-step affinity purification). 5. SDS-PAGE test. 6. QC and report.	1. 0.3mg-2mg purified protein. 2. Data and QC report.	Inquiry​
P110412 Mammalian-StepUp 8 - 12 Weeks	1. Condon optimization and gene synthesis (1000bp free). 2. Cell transfection. 3. Expression condition test: up to 3 different conditions. 4. 200mL fermentation. 5. Protein purification (1-step affinity purification). 6. WB and SDS-PAGE test. 7. QC and report.	1. 0.5mg-5mg purified protein. 2. Data and QC report.	Inquiry​
P110413 Mammalian-Comfo 9 - 13 Weeks	1. Condon optimization and gene synthesis (free of charge). 2. 2 expression vectors will be tested. 3. Transfection condition test: 6 conditions. Cell transfection. 4. Expression condition test: up to 3 different conditions. 5. 200mL - 1L fermentation. 6. Protein purification with 2 steps, purity polishing to >90%. 7. WB and SDS-PAGE test. 8. QC and report. 9. One time video meeting.	1. 1mg - 10mg purified protein. 2. Data and QC report.	Inquiry​
P110411 Mammalian-Ready 4 – 6 Weeks	1. Cell transfection. 2. 80mL cell culture. 3. Expression condition test: up to 2 different conditions. 4. Protein purification (1-step affinity purification). 5. SDS-PAGE test. 6. QC and report.	1. 0.3mg-2mg purified protein. 2. Data and QC report.	Inquiry​

 

Optional Service 1. Tag remove 2. 5L~200L fermentation, serum free 3. Western Blot for protein confirmation 4. Mass Spectrometry More information: Please Email to info@bio-bench.com if you need special service for Mammalian Cell Expression System.

Comparison of different types of service

Service type Content	Mammalian Ready	Mammalian StepUp	Mammalian Comfo
Codon optimization	-	✓	✓
Gene synthesis	-	✓	✓
Multiple vector or multiple cell line test	-	-	✓
Expression temperature test: HighT °C	✓	✓	✓
DNA to lipid ratio test	-	-	✓
Expression duration test (time points)	1	3	5
Fermentation volume	80mL	200mL	200mL – 1L
Affinity purification	✓	✓	✓
2nd purification: purity enhancement	-	-	✓
SDS-PAGE analysis	✓	✓	✓
WB analysis	-	✓	✓
Data, QC and report	✓	✓	✓
Video meeting support	-	-	✓
Purified protein	0.3mg – 2mg	0.5mg – 5mg	1mg – 10mg
	Inquiry​	Inquiry​	Inquiry​

 

List of Vectors	Commercial vectors and Bio Bench improved vectors. Please inquire for the up-to-date list.
List of Expression Strain	CHO-K1, HEK293T. Please inquire for the up-to-date list.

 

Stable Cell Line Generation Service

Mammalian-ST™ is the stable mammalian cell line development service provided by Bio Bench. Bio Bench has achieved more than 600 stable cell line projects since 2013, including more than 50 antibody drug expressing cell lines. The table below lists the cell types that have been successfully generated into stable cell line, do not hesitate to request a quote from us!

Stable mammalian cell line is one of the most important tools in drug discovery, toxicity test, biological research and bio-pharma industry. In order to establish stable cell line capable of long-term stably expressing the gene of interest (GOI), the operation is commonly achieved by transfection of a reconstructed plasmid containing the GOI together with a selection marker (antibiotic or fluorescent protein), through either liposome-mediated transfection or virus infection (or called viral transduction).

Bio Bench has successfully established the following host into stable cell line
CHO	CHO-K1	expiCHO	CHO-S
293F	CHO-DG44	HEK293	293T
expi293F	Vero (insect cell)	Your cell line here! Get a quote for free

 

Several typical applications including:

1. Hit screening/identification in therapeutic drug discovery.
2. Cell signaling.
3. Protein production, including antibody drug production.
4. Toxicity study.
5. Gene/mRNA function study.​

General process for stable cell line generation

​Transient expression and its pros and cons

The GOI (Gene of Interest) is commonly expressed by transient infection of mammalian cell line, and lead to successful expression of X milligram of protein. In small scale expression, transient transfection is 1) easy to operate – maximum 10 days training of new staff, 2) fast – 5 days from transfection to protein, and 3) reliable – relatively reproducible result >80%. However, once your project requires XX milligram, XXX milligram or even gram level of protein,  transient expression can be costly, laborious, time-consuming and risky. You may need to prepare large amount of plasmid and redundant cell culture priorly of transfection; all of the cells have to be in healthy condition at the time of transfection; if any problem happens – misoperation, contamination, low transfection efficiency and/or low expression level,  all of the procedures will have to be re-done.

​Stable pool/Stable cell line and its pros and cons

While talking about "stable", 2 concepts will be often discussed: stable pool and single clonal stable cell line. After transfection, the transfectants will be cultured in a medium containing growth inhibitors to remove the untransfected cells and low expression transfectants. The remaining group of cells is considered a stable pool. The stable pool may be seeded in 96-well (or 384-well, 1536-well, etc.) plate and subcloned to find out the stable single clone. This clone is defined as a stable single clonal cell line, or stable cell line. The stable cell line shows many advantages: constant GOI expression, easy cell culture and stable cell banking. It is thus ideal for midi-to-large scale protein expression or for long duration project.

Comparison between transient expression, stable pool and stable cell line

Service type Specification	Transient transfection	Stable pool	Stable cell line
Initial cost	+	++	+++
Midi scale cell culture or production cost	+++	++	++
Large scale cell culture or production cost	+++++	++	+
Operation complexity at small scale	++	+	+
Operation complexity at midi scale	+++	+	+
Operation complexity at large scale	+++++	+	+
Operator-to-operator variation	++++	+	+
Batch-to-batch variation (by the same operator)	++	+	+
Protein expression level	+	+++	+++++
Short term expression stability (1 - 3 days)	++++	+++++	+++++
Long term expression stability (10 – 20 days)	\	++	+++++
Regeneration stability	\	++	+++++
Conclusion	1.       Cell culture volume <100mL, or occasionally used cell culture. 2.       Protein amount <10mg, or occasionally used protein. 3.       Transfection is request by experiment protocol. 4.       Co-transfection of more than 1 plasmid. 5.       Small scale and proof-of-concept experiment.	1.       100mL < Cell culture volume < 20L, or regularly used cell culture (without specific requirement). 2.       10mg < Protein amount < 5g, or one time production but enough for a long period of usage. 3.       Non-commercial purpose, or less sensitive to cost. 4.       Low/no requirement for cell homogeneity. 5.       Low requirement for stability.	1.       Small to high volume cell culture, with or without high requirement. 2.       Small to high amount of protein production. 3.       Commercial purpose, cost effective. 4.       Experiment requires high level of cell homogeneity. 5.       High requirement for cell stability.
	Inquiry	Inquiry	Inquiry

 

Mammalian-ST™ Stable pool/Stable cell line generation service

Service and Timeline	Service Description (To be determined according to your specific project)	Deliverables	Price
P1521 – Stable pool Mammalian stable pool generation service 8 – 10 Weeks	1. Positive control protein/antibody characterization. 2. Codon optimization, gene synthesis, cloning and plasmid preparation. 3. Transient transfection test and antibiotic concentration determination. 4. Transfection and stable pool generation. 5. Stable pool characterization: expression level, cell viability, growth curve and total cell count. More characteristics optional! 6. SDS-PAGE, WB, ELISA, and/or FACS analysis. 7. Protein sample expression and purification. 8. QC and report.	- Selected and optimized stable pool. - Purified protein sample. - Data and QC report.	Inquiry​
P1526 – Stable cell line Mammalian stable cell line generation service 23 – 30 Weeks	All of the content from P1521 Stable pool generation service, together with the following: 1. Monoclonalization and best clones selection. 2. Fed-batch 1 (small culture volume) primary study and characterization. At least 6 characteristics will be tested for a duration of 8 – 15 days. 3. Fed-batch 2 (midi culture volume) enhanced study and characterization, optional. 4. Cell banking. 5. Whole genome sequencing of the selected clone, and backup plasmid establishment.	- Selected stable cell line. - Purified protein sample. - Data and QC report.	Inquiry​
More test options, including: 1.      Bioactivity test: binding/blocking assay, ADCC assay, etc. 2.      Affinity test by biacore or ForteBio method. 3.      Cell culture monitoring: Ammonia test, lactic acid test, pCO2 analysis, etc. 4.      Charge heterogeneity test. 5.      MS test: molecular weight, aggregation, etc. Would like to lean more? Seeking a specific testing method? Click on Inquiry​ and we will get back to you soon.