Differentiated cell-scaffold systems

Differentiated cell-scaffold systems Expanded PTFE Endothelial cells Vascular lining regeneration Ahlswede et al., 1994... 

Stem Cell-Scaffold Systems. Stem cells, also known as progenitor cells, are pluripotent cells with the ability to differentiate into a variety of cell types. The most widely stored stem cell is the mesenchymal stem cell (MSQ derived from bone marrow. In the embryo, these cells give rise to skeletal tissues, including bone, cartilage, tendon, ligament, marrow stroma, adipocytes, dermis, muscle, and connective tissue (Caplan, 1991). 

There is demand for more effective, localized, and need-based systems, which can be used in a plethora of biomedical applications, such as cancer targeting, controlled dmg delivery, tissue engineering or biosensors. By developing injectable hydrogels which can respond to variations in their environment and which can achieve the desired outcome (releasing a dmg or biological molecule, targeting cancerous cells, or cell differentiation in scaffolds), better medical techniques can be attained. 

Cell-based scaffold systems for bladder regeneration that are based on the use of isolated urothelial and smooth muscle cells, which are the key cellular components of the native bladder, have shown promise in early studies. In order to engineer bladder tissue in vitro, these cell types can be cultured and expanded in vitro, seeded on scaffolds, and allowed to adhere to the scaffold. They then form cellular structures on the scaffold, and this construct can be implanted into the patient. It is hypothesized that the tissue engineered 3D bladder, will exhibit fully differentiated cell populations after implantation in vivo and the presence of these cells will reduce the inflammatory immune response to the matrix as well as prevent graft contraction and shrinkage. 

Although research involving tissue engineering on Hpid-based molecular gel scaffolds may seem hmited at the present time, there exists significant potential for them to be developed into successful cell culture systems. The use of hpids, either as monomer, Hposome, or surface coating, in tissue engineering has provided powerful evidence of their essential roles in guiding cellular development, attachment, and differentiation. 

Silk fibers or monolayers of silk proteins have a number of potential biomedical applications. Biocompatibility tests have been carried out with scaffolds of fibers or solubilized silk proteins from the silkworm Bombyx mori (for review see Ref. [38]). Some biocompatibility problems have been reported, but this was probably due to contamination with residual sericin. More recent studies with well-defined silkworm silk fibers and films suggest that the core fibroin fibers show in vivo and in vivo biocompatibility that is comparable to other biomaterials, such as polyactic acid and collagen. Altmann et al. [39] showed that a silk-fiber matrix obtained from properly processed natural silkworm fibers is a suitable material for the attachment, expansion and differentiation of adult human progenitor bone marrow stromal cells. Also, the direct inflammatory potential of silkworm silk was studied using an in vitro system [40]. The authors claimed that their silk fibers were mostly immunologically inert in short and long term culture with murine macrophage cells. 

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