Mammailian cell expression system

Mammalian cell expression system has the most complicated posttranslational modifications closest to the native ones. Posttranslational modifications are required for appropriate biological activity, immunogenicity, and biodistribution. . Modifications such as the authentic glycosylation are essentially only provided by mammalian cells. For this reason, therapeutic and bioactive proteins are usually expressed in mammalian system.

Novoprotein’s mammalian expression system serves you with these advantages:

  • High Productivity:

    Our proprietary vectors support high-level expression of proteins in mammalian cells up to 200mg/L.

  • Two Expression Options:

    We offer both transient transfection and stable cell expression

  • Large-Scale Production:

    Our serum-free suspension cell culture (HEK293 and CHO) allows for gram scale protein production within one month.

  • Large Capacity:

    10 transient expression projects can be conducted in parallel.

  • High Success Rate:

    We have successful expressed more than 500 proteins in our mammalian system with yields above 1mg/L.

  • Procedure details

  • Timeframe and pricing

  • Case study

We start with your plasmid, cDNA, or simply the gene sequence information
We optimize the codon to maximize the expression level in your choice of system
Our proprietary vectors support high-level expression of proteins up to 200mg/L
Our serum-free suspension cell culture (HEK293 and CHO) allows for gram scale protein production within one month
Our highly advanced chromatography skills and complex column system guarantee the purity as we promise
  • Your gene of interest
  • Evaluate and choose the suitable expression system
  • Codon Optimization
  • Sub-clone into Expression Vectors
  • Transient trasfection
  • Establish stable cell line
  • Expression evaluation and optimization
  • Large scale expression
    (up to 100L, gram scale)
  • SDS Page Gel
  • Protein purification
    • Affinity column
    • Ion exchange chromatography
    • Hydrophobic chomatography
    • Size exclusion chromatography
  • Ready to go!
Gene Cloning and Expression Test
Strategy design Free 1 day
Codon optimization Free 2-3 weeks
Gene synthesis $0.40/bp
Subcloning gene of interest into expression vector $195.00
Detect protein expression 24-72 hours post transfection at 12-hour intervals $500.00 1 week
Selection of high-expression stable cell line (optional) $3,000.00-$5,000.00 2-3 weeks
Pilot Scale Expression and Purification
1 L HEK293 or CHO cell culture From $1,500.00 6-12 weeks
1mg of protein (soluble, > 80% purity)
Large Scale Production
Large-scale fermentation up to 500L with 60-80g cell pellet/L From $2,500.00 4-8 weeks
Purification to gram-scale protein  
Protein production to kilogram scale Please inquire  
Additional Services
Protein refolding    
Endotoxin removal    
Metabolic labeling    
Biotinylation    
Lyophilization    
Process development    
   
  • Protein properties:

    • secreted protein, with two 14kDa subunits
  • Challenges:

    • purify non-covalently linked, no tagged heterodimers
  • Strategy:

    • Clone each subunit to an individual construct
    • Co-transfection with two subunit constructs at 1:1 ratio
    • Blue Gel affinity: Purify based on binding properties
    • Ion exchange (4 exchanges in total) : Purify based on theoretical PI value
  • Turnaround time:

    • 6 weeks
  • Deliverable:

    • 17mg heterodimer protein above 95% purity
  • 1. Purification I – affinity blue gel: cell culture supernatant loaded

    Fig. 1 SDS-PAGE analysis of protein after affinity purification. Targeted protein bound to blue gel column.
    1: Sample;
    2-3: Flow-through;
    4: Elution (reduced);
    8: Elution (Non-Reduced)
  • 2. Purification II – cation exchange purification (SP-HP): elution of affinity blue gel desalted and loaded

    Fig. 2 SDS-PAGE analysis of protein after SP-HP ion exchange purification. Targeted protein bound at pH 6.0.
    1: sample; 2-3: Flow-through, 4-8: Elutions 1-5
  • 3. Purification III – 1st anion exchange purification (Q-HP): elution of SP-HP desalted and loaded

    Fig. 3 SDS-PAGE analysis of protein after Q-HP ion exchange purification. Targeted protein bound at pH 8.0.
    1: sample; 2-5: Flow-through, 6-8: Elutions 1-3
  • 4. Purification IV – 2nd anion exchange purification (Q-HP): elution of 1st Q-HP desalted and loaded

    Fig. 4 SDS-PAGE analysis of protein after Q-HP ion exchange purification. Targeted protein binding improved yet incomplete at pH 8.8.
    1: sample; 2: Flow-through, 3-6: Elutions 1-4; 9-10: Elutions (non-reduced)
  • 5. Purification V – 3rd anion exchange purification (Q-HP): elution of 2nd Q-HP desalted and loaded

    Fig. 5 SDS-PAGE analysis of protein after Q-HP ion exchange purification. Targeted protein binding is complete at low temperature.
    1: sample; 2: Flow-through, 3-5: Elution (reduced); 9-10: Elution (non-reduced)
  • 6. Final product: Concentration 0.5mg/ml with purity greater than 95%

    Fig. 6 SDS-PAGE analysis of final product.
    1: Reduced; 3: Non-reduced (heterodimer)

For more information about our mammalian expression service, contact us at sales@novoprotein.com or visit our Service page. In addition, we also offer other protein expression services including bacteria protein expression service, yeast protein expression services, baculovirus expression services. To know how other scientists speak of us, check out our References.

YOUR CONCERNS

Will I get what I am promised?
Our counter-contract ensures your terms of expectation are met.

I feel like losing control of data generation!
Our service team keeps tight monitoring and tracking over each step where data are generated.