NeuroMag is used to transfect DNA minicircles in Oligodendrocytes, Astrocytes and Neural Stem Cells

Part I: Minicircle vector technology limits DNA size restrictions on ex vivo gene delivery using nanoparticle vectors: Overcoming a translational barrier in neural stem cell therapy

J Control Release. 2016

AR Fernandes et al. 

Abstract

Genetically engineered neural stem cell (NSC) transplant populations offer key benefits in regenerative neurology, for release of therapeutic biomolecules in ex vivo gene therapy. NSCs are 'hard-to-transfect' but amenable to 'magnetofection'. Despite the high clinical potential of this approach, the low and transient transfection associated with the large size of therapeutic DNA constructs is a critical barrier to translation. We demonstrate for the first time that DNA minicircles (small DNA vectors encoding essential gene expression components but devoid of a bacterial backbone, thereby reducing construct size versus conventional plasmids) deployed with magnetofection achieve the highest, safe non-viral DNA transfection levels (up to 54%) reported so far for primary NSCs. Minicircle-functionalized magnetic nanoparticle (MNP)-mediated gene delivery also resulted in sustained gene expression for up to four weeks. All daughter cell types of engineered NSCs (neurons, astrocytes and oligodendrocytes) were transfected (in contrast to conventional plasmids which usually yield transfected astrocytes only), offering advantages for targeted cell engineering. In addition to enhancing MNP functionality as gene delivery vectors, minicircle technology provides key benefits from safety/scale up perspectives. Therefore, we consider the proof-of-concept of fusion of technologies used here offers high potential as a clinically translatable genetic modification strategy for cell therapy. 

NeuroMag Transfection Reagent is the first dedicated Magnetofection™ transfection reagent for neurons from 1 DIV to 21 DIV. It has proven to be extremely efficient in transfecting a large variety of primary neurons such as cortical, hippocampal, dorsal root ganglion and motor neurons with all types of nucleic acids. Moreover, high transfection efficiency was also achieved in primary astrocytes, oligodendrocyte precursors or neural stem cells as well as other cell lines (C6, B65, PC12, N2A...). Due to its unique properties, NeuroMag allows following transfected neurons during several days.