Fibroin-chitosan scaffolds

Altman et al. utilized a composite silk fibroin/chitosan scaffold for seeding and in vivo delivery of human ADSCs in a murine cutaneous wound model, and the delivery technique conferred physiological benefits to accelerated wound closure. ADSC seeded on a silk fibroin/chitosan scaffold differentiated into fibrovascular, endothelial, and epithelial components of restored tissue and enhanced the wound healing process [219]. 

Similar to the situation with 2D membranes, the basic molecular characteristics of chitosan such as DD also show great influence on the ability of chitosan scaffolds to modulate stem cell behavior. The chitosan scaffolds with a high DD can maintain the viability and pluripotency of buffalo embryonic stem-like (ES-Uke) cells [15]. However, the cell behavior on 2D and 3D environments are quite different. Comparison of MSC behavior in both 2D plates and chitosan/gelatin/chondroitin scaffolds demonstrates that the 3D microenviromnent can enhance osteogenesis and maintain the viability of cells [161]. The research by Altman et al. [162] found that the apparent elastic modulus and cytoskeleton F-actin fiber density were higher for ADSCs seeded in 3D sflk fibroin/chitosan scaffolds than on 2D glass plates (Fig. 13). 

Altman AM, Yan Y, Matthias N, Bai X, Rios C, Mathur AB, Song YH, Alt EU (2009) Human adipose-derived stem cells seeded on a silk fibroin-chitosan scaffold enhance wound repair in a murine soft tissue injury model. Stem Cells 27 250-258... 

Zhen-ding, S., Wei-qiang, L., and Qing-ling, F. (2009). Preparation and cytocompatibility of silk fibroin/chitosan scaffolds. Frontiers of Materials... 

She, Z., Liu, W., Feng, Q., 2009. Self-assembly model, hepatocytes attachment and inflammatory response for silk fibroin/chitosan scaffolds. Biomed. Mater. 4,045014. 

Fig. 13 Fluorescent Images and the corresponding line profiles of the F-actin fibers red) of ADSCs seeded on (a) glass surface and (b) silk fibroin/chitosan (SFCS) scaffold. F-actin fiber density of ADSCs was quantified and confirmed by line-profile analysis of the fibers using Image software. The x-axis is the distance in microns, and the peaks correspond to the intensity of the rhodamine-phalloidin stain (red), whose peak maximum occurs at the location of the fibers along the line. Nuclei were stained with DAPI (blue) [162]...

One of the interesting subjects in the field of tissue reconstruction is the use of adipose-derived stem cells incorporated silk fibroin-chitosan (SFCS) scaffold... 

Zhang K, Qian Y, Wang H et al (2010) Genipin-crosslinked silk fibroin/hydroxybutyl chitosan nanofibrous scaffolds for tissue-engineering application. J Biomed Mater Res 95 A 870-881... 

Natural polymers such as collagen, elastin, and fibrin make up much of the body s native extracellular matrix (ECM), and they were explored as platforms for tissue engineered constructs [34,47 9]. Polysaccharides such as chitosan, starch, alginate, and dextran were also studied for these purposes. Simultaneously, silk fibroin was widely explored for vascular applications due to its higher mechanical properties in comparison to other natural polymers, such as fibrin [48]. The utilization of natural polymers to create tissue-engineered scaffolds has yielded promising results, both in vitro and in vivo, due in part to the enhanced bioactivity provided by materials normally found within the human body [50]. However, their mechanical response is usually below the required values therefore, synthetic polymers have been explored to achieve the desired properties. 

Woitiski, C.B., Veiga, F., Riheiro, A., Neufeld, R., 2009. Design for optimization of nanoparticles integrating hiomaterials for oraUy dosed insulin. Eur. J. Pharm. Biopharm. 73, 25-33. Zang, M.Q., Zhang, Q.X., Davis, G., et al., 2011. Perichondrium directed cartilage formation in sUk fibroin and chitosan hlend scaffolds for tracheal transplantation. Acta Biomater. 7, 3422-3431. 

The incorporation of nanohydroxyapatite into a chitosan/silk fibroin nanofibrous membrane scaffold may provide a favorable mi-... 

A pristine chitosan/sUk fibroin nanofibrous membrane scaffold composite membrane scaffold w ith intrafibrillar nanohydroxyapatite w as prepared by in-situ blending of 10% or 30% nanohydroxyapatite before the electrospinning step. There was a deposition of nanohydroxyapatite through alternative soaking surface mineralization. 

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