Dear Prof. Li Wan

Yes, you mentioned it right.

Macrophages, like RAW264.7 cells, can be more difficult to transfect compared to other cell lines. This is due to their unique characteristics, namely their ability to phagocytose and their potential to have a tight membrane, which can hinder the entry of siRNA. They have evolved to recognize foreign nucleic acids and initiate an immune response, making them resistant to common transfection methods. They possess numerous enzymes, including proteases and nucleases, that can degrade exogenous DNA and RNA, making it harder for these molecules to reach the nucleus and be expressed.

I agree that RNAiMAX is suitable for siRNA transfection, but I recommend the use of HiPerFect transfection reagent which is a good choice for macrophages. It helps to deliver siRNA into primary cells, including primary human macrophages. Please try HiPerFect for RAW264.7 cells.

Regards,

Malcolm Nobre

Dear Li Wan

I hope that you have resolved your issue.

Otherwise I would like to present you our solution for RAW264.7 transfection with siRNA.

Since more than 20 years now we develop efficient and non-toxic transfection reagents - non toxic, because they are biodegradable. We propose several methods of transfection: physical (Magnetofection) or chemical (using lipid-based or polymer-based reagents) that share the same properties. They are all based on our patents and proprietary molecules that were specifically developed to this end.

■ Considering Magnetofection (the use of magnetic nanoparticles to deliver cargo into cells under the influence of a magnetic field), I would like to propose you to try our PolyMag Neo.

It is a magnetic nanoparticle formulation specifically developed for primary and hard-to-transfect cells. Originally intended for DNA transfection, this reagent has also been used in RAW cells to transport siRNA with high efficiency.

for example you can refer to the following publications:

→ Kondo Y. bioRxiv 2024 doi: https://doi.org/10.1101/2024.10.18.619173

→ Umezu R. Arterioscler Thromb Vasc Biol. 2020 Jun 4;ATVBAHA120314383.

► If you need any information on our reagents or if you want to try PolyMag Neo, please do not hesitate to contact me directly at:

🖂 [email protected]

best regards,

Cedric