Inhibition of MHCⅡExpression on Human Dermal Fibroblast Through CⅡTA Anti-sense RNA / 中华皮肤科杂志

Objective To investigate the feasibility of using anti-sense RNA against classⅡmajor histocompatibility complex(MHCⅡ)transactivator(CⅡTA),which might regulate MHCⅡexpression,to suppress the relative immune response.Methods Stable transfectants of dermal fibroblasts with pDarⅡ(pDarⅡ-D)were tested for the expression of classic MHCⅡ(HLA-DR,-DP,-DQ)antigens induced with recombinant human interferon-gamma(IFN-?).mRNA abundance of CⅡTA,and classic MHCⅡwas mea-sured by RT-PCR.IL-2mRNA expressed in T cells,stimulated by transfected dermal fibroblasts,was de-termined by mixed lymphocyte reaction.Results When induced with IFN-?,the expression of HLA-DR and-DP antigens on pDarⅡ-D was reduced by95.63%and87.89%,respectively.Meanwhile,the mRNA contents of CⅡTA and classic MHCⅡwere decreased significantly(P

Repair of porcine full-thickness skin defects with autologous tissue engineered skin / 中华外科杂志

<p><b>OBJECTIVE</b>To explore a feasible method to repair full-thickness skin defects with tissue engineered techniques.</p><p><b>METHODS</b>The skin specimens were cut from the Changfeng hybrid swines' abdomen, then keratinocytes and fibroblasts were isolated and harvested by trypsin, EDTA and type II collagenase. The cells were seeded in petri dishes for primary culture. When the cells were in logarithmic growth phase, they were treated with dispase II (keratinocytes) or trypsin (fibroblasts) to separate them from the floor of the tissue culture dishes. A biodegradable material-pluronic F-127 was prefabricated and mixed with these cells, and then the cells-pluronic compounds were seeded evenly into polyglycolic acid (PGA). Tinally the constructs were replanted to autologous animals to repair full-thickness skin defects. Histological changes were observed in 1, 2, 4 and 8 weeks postsurgery.</p><p><b>RESULTS</b>The cells-pluronic F-127-PGA compounds could repair autologous full-thickness skin defects. Histologically, the tissue engineered skin was similar to normal skin with stratified epidermis overlying a moderately thick collageneous dermis.</p><p><b>CONCLUSION</b>Tissue engineered skin can repair autologous full-thickness skin defects with primary-cultured keratinocytes and fibroblasts as seed cells and PGA as a cell carrier.</p>

Blocking transforming growth factor-beta receptor signaling down-regulates transforming growth factor-beta1 autoproduction in keloid fibroblasts / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To study transforming growth factor-beta1 (TGF-beta1) autoproduction in keloid fibroblasts and the regulation effect of blocking TGF-beta intracellular signaling on rhTGF-beta1 autoproduction.</p><p><b>METHODS</b>Keloid fibroblasts cultured in vitro were treated with either rhTGF-beta1 (5 ng/ml) or recombinant adenovirus containing a truncated type II TGF-beta receptor gene (50 pfu/cell). Their effects of regulating gene expression of TGF-beta1 and its receptor I and II were observed with Northern blot.</p><p><b>RESULTS</b>rhTGF-beta1 up-regulated the gene expression of TGF-beta1 and receptor I, but not receptor II. Over-expression of the truncated receptor II down-regulated the gene expression of TGF-beta1 and its receptor I, but not receptor II.</p><p><b>CONCLUSIONS</b>TGF-beta1 autoproduction was observed in keloid fibroblasts. Over-expression of the truncated TGFbeta receptor II decreased TGF-beta1 autoproduction via blocking TGF-beta receptor signaling.</p>

The determination and significance of VEGF in the serum of hemangioma patients / 中华整形外科杂志

<p><b>OBJECTIVE</b>Looking for an objective biomedical index to distinguish types and phases of hemangioma in order to provide an objective basis for selecting clinical treatment to hemangioma.</p><p><b>METHODS</b>ELISA (enzyme-linked immunosorbent assay) was used to determine serum VEGF concentration of 15 patients with proliferative hemangioma, 6 with involuted hemangioma, 6 with vascular malformation and 8 infants of the control group.</p><p><b>RESULTS</b>The serum VEGF concentrations of 15 proliferative hemangioma patients were significantly higher than those of involuted hemangioma patients, vascular malformation patients and control group infants. The serum VEGF concentrations of involuted hemangioma patients were a little bit higher than those of vascular malformation patients and control group infants, but without statistic significance.</p><p><b>CONCLUSIONS</b>ELISA could easily and accurately determine the serum VEGF concentration of different types and different phases of hemangioma. The determination of serum VEGF concentration could provide guidance for selecting a protocol of systemic corticosteroid treatment for proliferative hemangioma. Combined with gene expression and distribution of VEGF and its receptors and some other cytokines, the determination of serum VEGF concentration could help elucidate the mechanism of proliferative hemangioma.</p>

In vitro chondrogenic phenotype differentiation of bone marrow stem cells / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate the feasibility of chondrogenic phenotype differentiation of adult swine bone marrow stem cells(MSCs) in a defined medium as seeding cells in cartilage tissue engineering.</p><p><b>METHODS</b>A volume of 5 ml bone marrow was aspirated from swine iliac crest and cultured in the complete medium of DMEM-LG for two weeks. The growth and ultrastructure of the cultured MSCs were observed. Immunohistochemistry and in situ hybridization were applied to detect the expression of collagen type II.</p><p><b>RESULTS</b>The MSCs changed from a spindle-like fibroblastic appearance to a polygonal shape when transferred from the complete medium of DMEM-LG to a defined medium. A large amount of endoplasmic reticulum was observed in large Golgi ccmplex and mitochondria. The differentiation of MSCs toward chondrogenic phenotype was verified by the positive result of collagen type II through immunohistochemistry and in situ hybridization respectively.</p><p><b>CONCLUSIONS</b>Bone marrow stem cells obtained from adult swine can differentiate to be chondrogenic phenotype when cultured in vitro. MSCs can likely be served as optimal autogenous cell source for cartilage tissue engineering.</p>

Experimental study on chitosan as a scaffolds for tissue engineering cartilage / 中华显微外科杂志

Objective This experiment aimed to confirm whether man made porous chitosan scaffold is a appropriate scaffold for chondrocyte culutre of tissue engineering Methods Chondrocytes were seeded onto porous chitosan and chitosan collagen complex scaffolds for culture in a three dimensional environment The scaffolds in hydrophilia and adhesion to chondrocytes were observed with light microscope and scanning electron microscope The number of the cells attached to the scaffolds and the function of the cells were detected with MTT automated colormetric microassay Result Chondrocytes can multiple and secrete the matrix on the poros chitosan and chitosan collagensc scaffolds The cell adhesion rates were 81 25% and 87 50% respectively Conclusion Chitosan can be fabricated into a suitable three dimensional porous scaffold Porous chitosan collagen complex scafflold may be a more suitable scaffold for chondrocyte culutre of tissue engineering

THE EXPERIMENTAL STUDY ON CULTURE OF CHONDROCYTES SEEDED ONTO POLYGLYCOLIC ACID SCAFFOLDINGS COATING WITH DIFFERENT MATERIALS / 中华显微外科杂志

Objective:This experiment aims to find a appropriate scaffold for Tissue Engineer- ing.Methods:The chondrocytes were cultured when they were seeded onto PGA+PLA scaffolds coat- ing with Lecithin(LEC)and Poly-l-lysine(PLYS)together and respectively.With light microscope and scanning electron microscope,the observation of the scaffolds in hydrophilia and adsorptivity to chondrocytes and the function of the cells was made.Results:The PGA scaffolds coating with LEC and PLYS have better hydrophilia and adsorptivity to the cells;on which the chodrocytes produce more ma- trices.Conclusion:LEC can chang the hydrophilia of the scaffolds;while PLYS can strengthen the ad- sorptivity of the scaffolds;the PGA coating with LEC and PLYS is an ideal scaffold in Tissue Engineer- ing.