Characterization of sequential collagen-poly(ethylene glycol) diacrylate interpenetrating networks and initial assessment of their potential for vascular tissue engineering

Abstract

Collagen hydrogels have been widely investigated as scaffolds for vascular tissue engineering due in part to the capacity of collagen to promote robust cell adhesion and elongation. However, collagen hydrogels display relatively low stiffness and strength, are thrombogenic, and are highly susceptible to cell-mediated contraction. In the current work, we develop and characterize a sequentially-formed interpenetrating network (IPN) that retains the benefits of collagen, but which displays enhanced mechanical stiffness and strength, improved thromboresistance, high physical stability and resistance to contraction. In this strategy, we first form a collagen hydrogel, infuse this hydrogel with poly(ethylene glycol) diacrylate (PEGDA), and subsequently crosslink the PEGDA by exposure to longwave UV light. These collagen-PEGDA IPNs allow for cell encapsulation during the fabrication process with greater than 90% cell viability via inclusion of cells within the collagen hydrogel precursor solution. Furthermore, the degree of cell spreading within the IPNs can be tuned from rounded to fully elongated by varying the time delay between the formation of the cell-laden collagen hydrogel and the formation of the PEGDA network. We also demonstrate that these collagen-PEGDA IPNs are able to support the initial stages of smooth muscle cell lineage progression by elongated human mesenchymal stems cells.

Recent Advances in Photo-Crosslinkable Hydrogels for Biomedical Applications

“…Due to this, it allows growth of cancer cells and formation of tumorspheres, indicating its great potential in developing various types of 3D in vitro cancer model, such as a breast cancer model, gastrointestinal cancer model and bone cancer model [44]. However, in order to utilize it as a 3D cell culture platform for developing tissue-engineered constructs or implants, it has to be combined with other biomaterials possessing cell adhesive properties, such as HA, GelMA, collagen and polyaniline [31,32,41,48]. PEGDA/GelMA hybrid hydrogel and PEGDA/collagen hybrid hydrogel were loaded with adult stem cells, respectively, for tooth and vascular regeneration [31,32].…”

“…However, in order to use PEGDA hydrogel for tissue engineering applications, the degradation rate of PEGDA hydrogel should be increased to allow cells to remodel their microenvironment or extracellular matrix [46]. The degradation rate of PEGDA hydrogel can be improved by combining it with other enzymatically or hydrolytically degradable materials [32]. For instance, degradation of PEGDA was increased up to 80 after 14days of immersion in collagenase solution in which GelMA was added to form PEGDA/GelMA hybrid hydrogel for tooth tissue engineering [31].…”

“…However, in order to utilize it as a 3D cell culture platform for developing tissue-engineered constructs or implants, it has to be combined with other biomaterials possessing cell adhesive properties, such as HA, GelMA, collagen and polyaniline [31,32,41,48]. PEGDA/GelMA hybrid hydrogel and PEGDA/collagen hybrid hydrogel were loaded with adult stem cells, respectively, for tooth and vascular regeneration [31,32]. PEGDA/HA hybrid hydrogel was employed to promote bone regeneration, which can be functionalized with laponite XLG nanoclay (a composite that releases bioactive ions Mg 2+ and Si 4+ ) to create a favorable microenvironment for in vivo osteogenesis [41] (Figure 2B).…”

Osteoinductive PolyHIPE Foams as Injectable Bone Grafts

“…Specifically, gene expression for runx2, ALP, OPN, Col1a1, and OCN was quantified relative to the housekeeping gene b-actin. In brief, mRNA was extracted using the Dynabeads mRNA DIRECT Kit (Ambion, Life Technologies) according to the method described by Munoz-Pinto et al 41 Each polyHIPE specimen was rinsed with 250 mL DPBS for 5 min. Thereafter, 250 mL of the provided lysis binding buffer was added over the sample and incubated at room temperature for 10 min.…”

A Three-Dimensional Chondrocyte-Macrophage Coculture System to Probe Inflammation in Experimental Osteoarthritis

“…Poly(ethylene glycol) diacrylate (PEGDA)-based hydrogels were used in this study for the establishment of the 3D coculture system, due to their widespread use in cartilage tissue engineering, [34][35][36][37] their easily tunable mechanical properties, 38,39 and their ability to significantly resist cell adhesion even in serum-containing culture environments relative to many biomaterials. 34,40,41 This latter property permits desired cell adhesion to be ''programmed'' into the PEGDA network through conjugation of bioactive moieties.…”