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TransIT-PRO Transfection Kit – 1.0 mL (with boost)

High, Reproducible Protein Yield in Suspension CHO and 293 Cells

SKU MIR 5700 Categories ,



Ideal for Biotherapeutic Protein Production in Suspension CHO and 293 Cells

Reach critical stages faster. Decrease time to produce usable protein by maximizing target protein yields through transient transfection. The TransIT-PRO® Transfection Reagent & Kit use animal origin free components designed for high and reproducible protein yield in suspension CHO and 293 derived cells. Since it is compatible with varied media formulations, the same media can be used for both transient and stable expression. Use with CHOgro® Expression Media for highest yield in suspension CHO cells. TransIT-PRO® outperforms linear PEI in protein yield, while providing a cost-effective alternative to FreeStyle™ MAX.

  • High Protein Yield – in Suspension CHO and 293 cells, including CHO-S and Expi293F™ cells
  • Compatible with Multiple CHO Media Formulations – Use with CHOgro® Expression Medium to Achieve Highest Yields
  • Simple Workflow – Reproducible Protein Expression with Minimal Optimization


SKU: MIR 5700

Supporting Data


High Efficiency Transfection of CHO-S Cells Using the TransIT-PRO® Transfection Reagent. Plasmid DNA encoding EGFP was delivered by transient transfection with the TransIT-PRO® Transfection Reagent (1:1) (reagent:DNA ratio, volume:weight) using 1 µg plasmid DNA per milliliter of culture and cell a density of 2 x 106 cells/ml in the CHOgro® Expression Medium at the time of transfection.  FreeStyle™ CHO-S cells were cultured in CHOgro® Expression Medium  and plated into non-treated 6-well plates (2 ml/well) for transfection. (A) GFP levels and cell viability (propidium iodide) were measured 48 hours post-transfection using a Guava® easyCyte™ 5HT flow cytometer (EMD Millipore). (B) Images were captured using a Zeiss Axiovert inverted fluorescence microscope.


TransIT-PRO® Yields Multi-fold Increases in Antibody Titer in Conjunction with CHOgro® Expression Medium. Human IgG1 was produced by transient transfection using TransIT-PRO® (1:1), FreeStyle™ MAX (1.25:1.25) or 25kDa linear PEI (6:1) transfection reagents according to the manufacturers’ or published protocol (reagent:DNA ratio). Transfections were performed using 1 µg plasmid DNA per milliliter of culture and cell densities of 2 x 106 cells/ml or 1x 106 cells/ml for the CHOgro® Expression Medium (red bars) or FreeStyle™ Expression Medium (blue bars), respectively, at the time of transfection. FreeStyle™ CHO-S cells were cultured in CHOgro® Expression Medium or FreeStyle™ CHO Expression Medium and plated into non-treated 6-well plates (2ml/well) for transfection. Antibody levels were also analyzed from day 6 clarified supernatants using a human IgG ELISA (ZeptoMatrix). Error bars represent the standard deviation of triplicate technical replicates.


Achieve High Protein Yields Using TransIT-PRO® Transfection Kit in Suspension 293 Cells. Ten different secreted (non‐antibody) proteins were transiently expressed in FreeStyle™ 293‐F cells (Life Technologies) using TransIT‐PRO (1.5:1) or 293fectin™ (Life Technologies, 2:1) transfection reagents according to manufacturer’s protocol. Cells were grown in FreeStyle™ 293 Expression Medium at transfected at a density of 1 x 106 cells/ml. The scale of the transfection for each protein varied between 1‐6 L of culture. More experimental details here. (PDF)

Data courtesy of a TransIT‐PRO pharmaceutical customer.



Storage Conditions
All Configurations: Store at -20°C

Product Guarantee
All Configurations: 1 year

Usage Statement
All Configurations: For Research Use Only.

Animal Origin Statement
All Configurations: This product is animal origin free.


Technical Product Literature

Full Protocols
TransIT-PRO® (includes PRO Boost) Full Transfection Protocol (PDF)
TransIT-PRO® Full Transfection Protocol (PDF)

Additional Protocol
TransIT-PRO® for Expi293F™ Cells (PDF)

Quick Reference Protocols
TransIT-PRO® (includes PRO Boost) Quick Ref Protocol (PDF)
TransIT-PRO® Quick Ref Protocol (PDF)



Additional Resources

Application Page: Learn more about using TransIT-PRO® for high yield protein production >>
Protocol: Transfecting Expi293F™ Cells using TransIT-PRO Reagent >>
White Paper: Selecting a Transfection Reagent for Large Scale Protein Production in Suspension 293 Cell Types (PDF)
Article: Maximize Protein Expression in CHO Cells (PDF)


See the TransIT-PRO FAQs

Using transfection reagents and enhancers from Mirus has given our platform a competitive advantage. Increasing efficiency and lowering costs for all of our porgrams.


Sally Mader, PhD
ZYZ Theraputics