Genetically engineered angiogenic cell sheets using magnetic force-based gene delivery and tissue fabrication techniques

Abstract

A major limitation in tissue engineering is the insufficient formation of blood vessels in implanted tissues, resulting in reduced cell density and graft size. We report here the fabrication of angiogenic cell sheets using a combination of two magnetic force-based techniques which use magnetite cationic liposomes (MCLs), magnetofection and magnetic cell accumulation. A retroviral vector encoding an expression cassette of vascular endothelial growth factor (VEGF) was labeled with MCLs, to magnetically attract the particles onto a monolayer of mouse myoblast C2C12 cells, for gene delivery. MCL-mediated infection increased transduction efficiency by 6.7-fold compared with the conventional method. During the fabrication of the tissue constructs, MCL-labeled cells were accumulated in the presence of a magnetic field to promote the spontaneous formation of a multilayered cell sheet. VEGF gene-engineered C2C12 (C2C12/VEGF) cell sheets, constructed using both magnetic force-based techniques, were subcutaneously transplanted into nude mice. Histological analyses revealed that on day 14 the C2C12/VEGF cell sheet grafts had produced thick tissues, with a high-cell density, and promoted vascularization. This suggests that the method described here represents a powerful strategy in tissue engineering.

Liposomes in tissue engineering and regenerative medicine

“…2007 [188] in vitro reconstruction of three-dimensional bone tissues cell sheets into nude mice produced thick tissues, with a high cell density, and promoted vascularization 2010 [192] MSC sheet for therapeutic angiogenesis and tissue regeneration human MSCs incubated with MCLs formed multi-layered cell sheets according to magnetic force. MSC sheets layered onto the ischaemic tissues of nude mice before skin closure showed greater angiogenesis than the control and MSC injected 2011 [193] construction of three-dimensional artificial skeletal muscle tissues…”

Cell surface engineering with polyelectrolyte-stabilized magnetic nanoparticles: A facile approach for fabrication of artificial multicellular tissue-mimicking clusters

“…To date, most published techniques have employed passive internalization of MNPs via endocytosis, which allows for effective magnetic modification of cells [11][12][13]. However, uptake of MNPs by cells entails several major drawbacks, such as (1) a lengthy internalization process, requiring up to 72 h of co-incubation of MNPs with cells [14,15] and (2) potential toxic effects of early-stage cytoplasminternalized nanoparticles [16].…”

Exploitation of physical and chemical constraints for three-dimensional microtissue construction in microfluidics

“…The paramagnetic particles remain in the cells after 3 weeks, as revealed by transmission electron microscopy. Akiyama et al 96 presented a method for the fabrication of cell sheets ͑monolayer of mouse myoblast C2C12͒ using magnetic fields and magnetic cationic liposomes. Magnetic microparticles were also used in tissue engineering for fabrication of 2D and 3D scaffolds with controllable pores.…”