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Applications | Low Toxicity Transfections

High Efficiency, Low Toxicity Transfections with TransIT® Transfection Reagents

Understanding the impact of transfection mediated toxicity is important for every researcher. Observed toxicity is largely dependent on the transfection reagent and cell type. Choosing a transfection reagent that balances high efficiency nucleic acid delivery and low cellular toxicity is imperative to achieving reliable experimental results. Providing researchers gene delivery expertise since 1995, Mirus TransIT® transfection reagents give researchers:
  • High efficiency, low toxicity transfections
  • Minimal off-target effects
  • Reduction in experimental bias

Low Toxicity in HeLa Cells

Mirus Bio Broad Spectrum Transfection Reagents Outperform Lipofectamine® 2000



Mirus Broad Spectrum Transfection Reagents, TransIT®-LT1 and TransIT®-2020 Outperform Lipofectamine® 2000. HeLa cells were transfected with a GFP encoding plasmid DNA using either TransIT®-LT1, TransIT®-2020 or Lipofectamine® 2000 at reagent-to-DNA ratios of 3:1 for all reagents. Phase contrast and GFP images were taken in the same field of view at 8 and 24 hours post-transfection. Cells transfected with TransIT®-LT1, TransIT®-2020 remain healthy after 24 hours while maintaining high transfection efficiency, whereas cells transfected with Lipofectamine® 2000 display significant cytotoxicity after 24 hours.


TransIT® Broad Spectrum Reagents Balance High Efficiency Delivery with Low Toxicity. HeLa cells were transfected with luciferase encoding plasmid DNA using either TransIT®-LT1, TransIT®-2020 or Lipofectamine® 2000 for 24 hours. Transfection was measured by luciferase activity using a conventional assay. Cytotoxicity was assessed by quantifying the LDH released from the cytosol of damaged cells compared to cells alone. Higher transfection efficiency and lower cytotoxicity was observed in cells transfected with TransIT®-LT1 and TransIT®-2020 at optimal ratios than cells transfected with Lipofectamine® 2000.

TransIT® Transfection Reagents Minimize the
Stress Response in HeLa Cells

Mirus TransIT® Transfection Reagents Minimize the Stress Response in Transfected HeLa Cells. Stress-related gene expression changes were determined by RT-qPCR from total RNA samples harvested from HeLa cells that were transfected with TransIT®-LT1, TransIT®-2020 or Lipofectamine® 2000 at 8 and 24 hours. Eighty-four genes were analyzed using the Human Stress Response 96 StellARray™ (Lonza). At both time points, the number and magnitude of stress-related gene expression changes were lower when cells were transfected with TransIT®-LT1 or TransIT®-2020 than when cells were transfected with Lipofectamine® 2000.


Transfections with TransIT®-LT1 or TransIT®-2020 Affect Fewer Core Pathways than Transfections with Lipofectamine® 2000. Canonical pathway enrichment analysis shows the primary biological processes impacted in HeLa cells that were transfected with TransIT®-LT1, TransIT®-2020 or Lipofectamine® 2000 at 24 hours. The negative log of the p values is the probability of obtaining these genes associated with the given pathways by random chance. The bar line at the bottom of each graph is derived from the ratio of the number of genes on our list associated with a given pathway divided by the total number of genes that make up that pathway. Pathway analysis was performed using Pathway Analysis (Ingenuity Systems). Representative data from two independent tests is shown.

TransIT® Transfection Reagents Deliver to Multiple Cell Types with Minimal Toxicity

Four commonly used cell types: HepG2, THP-1, NT2 and HUVEC were analyzed for luciferase expression as well as cytotoxicity using a lactate dehydrogenase (LDH) assay for membrane leakage. At recommended doses, both TransIT®-LT1 and TransIT®-2020 display only minor cytotoxicity while delivering plasmid DNA with high efficiency into all four different cell lines tested. However, toxicity was most apparent, sometimes reading near 50% when using Lipofectamine® 2000 to deliver nucleic acid.

Products Low Toxicity Transfections

TransIT®-LT1 Transfection Reagent

  • Broad Spectrum DNA Delivery – Utilize one transfection reagent and protocol for a variety of cells
  • High Efficiency Delivery – Achieve expression in a large population of cells for experimental success
  • Deliver Single or Multiple Plasmids – Suitable for applications such as virus production

  • Broad Spectrum DNA Delivery – Achieve high expression in many cell types, including hard to transfect cell lines and primary cells
  • Gentle to Your Cells – Balances high efficiency nucleic acid delivery and low cellular toxicity
  • Animal Origin Free – High performance with maximum compatibility


Technical Resources

Don’t See Your Cell Type? Consult Reagent Agent® Transfection Database
Citation Database: Check if our reagents have been used by other researchers to transfect your cell type
Technical Support: Speak directly with a transfection expert

For more information on transfection for RNAi applications, additional resources can be found on the Mirus Bio website:

TransIT-2020 Transfection Reagent

TransIT-LT1 Transfection Reagent