Patterned prevascularised tissue constructs by assembly of polyelectrolyte hydrogel fibres

Abstract

The in vivo efficacy of engineered tissue constructs depends largely on their integration with the host vasculature. Prevascularisation has been noted to facilitate integration of the constructs via anastomosis of preformed microvascular networks. Here we report a technique to fabricate aligned, spatially defined prevascularised tissue constructs with endothelial vessels by assembling individually tailored cell-laden polyelectrolyte hydrogel fibres. Stable, aligned endothelial vessels form in vitro within these constructs in 24 h, and these vessels anastomose with the host circulation in a mouse subcutaneous model. We create vascularised adipose and hepatic tissues by co-patterning the respective cell types with the preformed endothelial vessels. Our study indicates that the formation of aligned endothelial vessels in a hydrogel is an efficient prevascularisation approach in the engineering of tissue constructs.

Interfacial Polyelectrolyte Complex Spinning of Cellulose Nanofibrils for Advanced Bicomponent Fibers

“…This combination of characteristics have been recognized as beneficial for preparation of fibers for biomedical applications. [44][45][46][47] As an additional benefit, large scale high throughput IPC spinning has been demonstrated to be feasible. [48][49][50] While IPC spinning of colloidal materials such as carbon nanotubes and protein amyloids into strong fibers has been shown, [49][50][51] IPC spinning of CNF-based fibers remains yet to be demonstrated.…”

Spatial Patterning of Stem Cells to Engineer Microvascular Networks

“…For instance, Leong et al used this approach to assemble well-ordered fi brous structures from polyionic droplets composed of rat methylated collagen (RMC), water-soluble chitin, and sodium alginate (Fig. 4b ) [ 169 ]. The goal of this study was to develop spatially defi ned vascularized tissues using co-culture [ 167 ] of human microvascular ECs (hMVECs) and human MSCs.…”

“…For instance, Hashi et al developed aligned PLLA nanofi brous scaffolds to guide the assembly of MSCs along the direction of fi bers. MSCs were organized [ 169 ] in a similar fashion as compared to SMCs within native arteries, suggesting that the fabricated constructs could be potentially applied in engineering vascular grafts [ 175 ]. In another study, hyaluronan-based fi brous scaffolds were used to promote the differentiation of EPC toward ECs lineage [ 176 ].…”

“…Aligned endothelial tubes were detected after 24 h of culture (Fig. 4c ) which lasted for 56 days and ultimately integrated with the host vasculature [ 169 ].…”

Nano-film modification of collagen hydrogels for controlled growth factor release

“…In particular, hydrogels can form a threedimensional organic network with a high water content into which desired functions can be incorporated. Due to their unique, versatile, and controllable properties, numerous new nanotechnology approaches have emerged to develop modified hydrogels for specific applications, particularly in tissue engineering, stem cell engineering, and cancer research (Drury and Mooney, 2003;Levenberg et al, 2005;Discher et al, 2009;Liu et al, 2010;Leong et al, 2013).…”