Cellular scaffolds

Jeong and coworkers have reported peptide-based thermo-gelling systems using PEG-b-polyAla as an injectable cellular scaffold [315]. The polymer aqueous solution undergoes sol-gel transition as temperature increases. The fraction of the p-sheet structure of the poly Ala dictated the population and thickness of fibrous nanostructure in the hydrogel, which affected the proliferation and protein... 

Neuss and coworkers have reported the possibility of SMPs using PCL dimethacrylate copolymers as cellular scaffold for tissue engineering. Behaviors of different cells from three different species (human mesenchymal stem cells, human mesothelial cells, and rat mesothelial cells) on the matrices were investigated, and the differentiation capacity of mesenchymal stem cells on the matrices was also analyzed [329]. The SMPs proved biocompatibility for all tested cell types, supporting viability and proliferation. The SMPs also supported the osteogenic and adipogenic differentiation of human mesenchymal stem cells 3 weeks after induction. 

The cytoskeleton is a cellular scaffold contained within the cytoplasm. It is present in all cells, including prokaryotes. It is a dynamic structure that maintains cell shape, protects the cell and mediates cellular motion and intracellular transport, as well as cell division. 

The cytoskeleton is a cellular scaffold within the cytoplasm of the cell or within structures such as flagella, cilia, and lamellipodia. The cytoskeleton plays a crucial role in cellular integrity/structural support, cell division, cell motility, and intracellular transport. Staining of the cytoskeleton may be achieved by immunofluorescence in fixed cells however there are also dyes available, such as fluorescently labelled phalloidin, which directly labels actin filaments, as well as tubulin tracker which labels microtubules (Molecular Probes). Phalloidin is poorly permeable to living cells however, phalloidin derivatives with improved permeability properties are also available. Although both phalloidin derivatives and microtubule tracker can be used in live cells, it should be noted that both dyes are toxic as they inhibit cell division, and therefore limits their applications. 

Cellular scaffolds represent a middle ground between in vivo and in vitro engineering. Engineers can create a scaffold in a laboratory environment and... 

Artificial matrices have also been successful in treating disorders that affect the kidney, bone, and cartilage. Researchers are hopeful that cellular scaffolds could eventually allow the creation of entire organs by coaxing cells to develop around a scaffold designed as an organ template. 

A bilayer scaffold including an outer layer of an electrospun PEUU scaffold and an inner layer of porous PEUU scaffold was developed to address the cellular-ization issue [15]. The electrospun layer provided the mechanical support, while the porous scaffold layer supplied space for cell loading and infiltration. Prior to implantation, the cells including primary cells or stem cells were uniformly seeded into the porous layer using a customized vacuum device [15,40 2]. Rat vascular smooth muscle cells were seeded into the bilayer conduit and cultured in vitro for 2 days, and then this cellularized scaffold was implanted into the rat aorta model [42]. After 8 weeks, the patency of the cellularized scaffolds increased by 75% compared to 38% of the acellular scaffold. The failed scaffolds were blocked due to the intimal hyperplasia. The patent scaffolds contained a neointimal layer consisting of multiple layers of the immature contractile smooth muscle... 

Kesti, M., Muller, M., Becher, J., Schnabelrauch, M., D este, M., Eglin, D., Zenobi-Wong, M., 2015. A versatile bioink for three-dimensional printing of cellular scaffolds based on thermally and photo-triggered tandem gelation. Acta Biomater. 11, 162—172. 

The diffusion-reaction problem in a scaffold that progressively fills with cells is mathematically more challenging than the classical isothermal diffusion-reaction problem that has been extensively studied in the engineering literature [131]. Similar to the active sites in a catalyst particle, cells act as sinks for the nutrient that is transported into the scaffold. In the case of a cellularized scaffold, however, these sinks move constantly, multiply and may even die by apoptosis or necrosis. At first, this problem may seem intractable because of the complex interplay between mass transport and cell population dynamics induced by the temporal and spatial variations of the cell distribution function y. 

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