Experimental research of type Ⅱ collagen composite glycosaminoglycan scaffold in hUCMSCs chondrogenic induction / 重庆医学

Objective To investigate the chondrogenic feasibility of the human umbilical cord derived mesenchymal stem cells (hUCMSCs)as cartilage tissue engineering seed cells ,type Ⅱ collagen composite glycosaminoglycan scaffold as the cellular carrier and cell‐scaffold complex .Methods The type Ⅱ collagen composite glycosaminoglycan scaffolds was prepared .The pore diameter , porosity and hydrophilia of scaffold materials were observed and measured by electronic microscope .The corresponding histological analysis on the scaffold materials was performed .hUCMSCs of P3 generation were cultured and identified .The hUCMSCs suspen‐sion was inoculated in the type Ⅱ collagen composite glycosaminoglycan scaffold for conducting culture without adding inducer .The samples were taken out after 3 weeks and performed the toluidine blue and safranin O staining ,type Ⅱ collagen immunohistochemi‐cal staining and SEM scanning .Results hUCMSCs of P3 generation highly expressed the mesenchymal cell marker CD29 and CD105 ,while hardly expressed endothelial cells of CD34 and hematopoietic cell markers .The type Ⅱ collagen composite glycosami‐noglycan scaffold presented white porous foam like ,the porosity was (91 .8 ± 2 .17)% ,the average pore diameter was 110‐230 μm , which was homogeneously distributed and had interpenetration .The scaffold showed good hydrophilicity with the water absorption expansion rate of (213 .71 ± 1 .31)% .The scaffold staining of toluidine blue ,safranin O and type Ⅱ collagen was positive .The car‐tilage‐like tissues were observed ,and gradually increased in the surface of cell‐scaffold complex along with culture ,which were posi‐tive in Toluidine blue ,safranin O and type Ⅱ collagen staining ,the electronic microscopic observation displayed that the cells were actively proliferated in the scaffold ,closely adhered with the materials ,the cartilage‐like cells and a large number of peripheral colla‐gen fibers with zigzag connection could be seen .Conclusion Compositing hUCMSCs and type Ⅱ collagen composite glycosamin‐oglycan scaffold could construct tissue‐engineering cartilage in vitro without induction ,which lays a certain experimental foundation for the repair of cartilage damage .

Study of proliferation of chondrocytes co-cultured with platelet rich gel / 局解手术学杂志

Objective Preparing platelet rich gel through two-times centrifugal technique and co-culturing chondrocytes with PRG, then observing the proliferation and gene expression of chondrocytes, in order to provide a favorable way to prepare tissue engineering cartilage. Methods Centrifugating venous blood of rabbit through two-times centrifugal technique to obtain platelet rich plasma( PRP) ,then detecting the concentration of various growth factor in PRP. Admixing PRP with chondrocytes of rabbit and activating them with activator. After co-culti-vation,the proliferation of chondrocytes through MTT method and expression of ACAN,CollagenⅡand SOX-9 through realtime-PCR were ob-served,and compared with common cultured chondrocytes. Results The concentrations of PDGF-AB,TGF-β1,IGF-1 and VEGF in PRG were significantly higher than those in blood(P<0. 05). After co-cultivation, the proliferation rate of chondrocytes and the expression of ACAN,Collagen Ⅱ and SOX-9 were significantly higher than that of common cultured chondrocytes(P<0. 05). Conclusion Co-culturing chondrocytes with PRG is able to promote the proliferation and gene expression of chondrocytes. We considered that it is a excellent method to construct tissue engineering cartilage.

Application of novel silicon bioinert perforated chambers in tissue-engineering of cartilage in vivo / 中华医学美学美容杂志

Objective To explore the potential applications of a chamber for in vivo tissue engineering,and to establish a novel model for in vivo tissue-engineered cartilage.Methods Auricular chondrocytes were isolated,cultured and identified from the ears cartilages of New Zealand white rab bits; rabbit auricular chondrocytes(RACs) were seeded into the scaffolds:(1) RACs were seeded into collagen gel scaffold; (2) RACs were seeded into PLGA/collagen gel scaffold in vitro,and the compos ites were placed into the chambers and implanted in the donor rabbit.As control groups,the composites were implanted directly subcutaneously in the donor rabbit without using chambers,and the contents were harvested at 8 weeks after implantation.Gross examination,histologic and immunohistochemical staining and RT-PCR test were performed to evaluate the harvested contents.Results Under the same conditions inside the chambers,the contents formed into new cartilage-like tissue by histo logical and immunohistochemical staining and RT-PCR.In contrast,in the control groups without chambers displayed vascular invasion and inflammatory reaction in the subcutaneous layer of skin,which eventually led to fibrous tissue or absorption.Conclusions Cartilage is successfully constructed in an immunocompetent animal model using a bioinert perforated chamber.This method is effective in creating a relatively favorable environment for cartilage regeneration,which may provide a valuable reference for the clinical application of tissue regeneration.

Research Progress of Biodegradable Scaffolds in Constructing Tissue Engineering Cartilage / 中国生物工程杂志

Articular cartilage repair is limited. Current treatments for cartilage defect are less satisfactory, and rarely restore full function or return the tissue to its native normal state. The rise of tissue engineering holds great promise for the generation of functional cartilage tissue substitutes. The history of cartilage tissue engineering and highlights the applications and advantages of various kinds of scaffolds in cartilage tissue engineering, such as native scaffolds, synthesis scaffolds, composite scaffolds and nanometer scaffolds had been introduced. But native scaffolds have weak strength and immunogenicity insufficiency, synthesis scaffolds degrade quickly, whose degrading products have cytotoxicity,which need further improvement. The application of superficial decoration overcomes the disadvantage of some scaffolds to an extend. Composite scaffolds possess the advantages of several scaffolds, it points out the direction of future scaffolds research. The development of Nanometer technique endows newly-synthesis scaffolds with nano-grade, thus it has some advantages and give a new way for the development of tissue engineering. At the end, the problems of these scaffolds, their trend of development and perspective studies were discussed.