Question: 

The use of magnetic nanoparticles (MNPs) enables to combine gene therapy with cell replacement. Because different physical properties of the MNPs are required for these two applications, we have established a novel method where two different types of MNPs are used for efficient viral transduction and site-specific positioning of endothelial cells (ECs) in vessels under flow conditions.

Methodology: 

Various MNPs were screened for lentivirus binding and magnetic endothelial cell labeling. Based on these experiments two different MNPs were selected and transduction efficiency as well as EC magnetization were examined for their combined use.

Results: 

The combination of PEI-Mag2 and NDT-Mag1 particles yielded efficient lentiviral transduction as well as high magnetic responsiveness of ECs which was sufficient for their retention at the vascular wall under ex vivo flow conditions. Cell biological characteristics of endothelial cells such as expression of platelet endothelial cell adhesion molecule (PECAM) and endothelial nitric oxide synthase (eNOS) as well as vascular network formation were unperturbed by this procedure.

Conclusion: 

The application of two different MNPs provides optimal viral transduction combined with magnetic cell labeling. This approach could be helpful for ex vivo gene therapy and site-specific cell replacement in the vascular system.