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Objective@#To explore the biological characteristics of synovial fluid-derived mesenchymal stem cells (SF-MSCs) cultured in serum-free medium and the ability of in vitro reconstruction of three-dimensional cartilage combined with scaffold material.@*Methods@#Human SF-MSCs were cultured in serum medium and mesenchymal stem cells medium-serum free (MSCM-sf) respectively, then the proliferative ability and morphology of SF-MSCs were compared; The third passage SF-MSCs cultured in MSCM-sf were identified by flow cytometry, three-way(chondrogenic, osteogenic, adipogenic)differentiation assay and induced for chondrogenic differentiation when combined with polyglycolic acid/polylactic acid (PGA/PLA).@*Results@#SF-MSCs cultured in MSCM-sf had better morphology and proliferative ability than that cultured in serum medium. The expression levels of positive markers of the third passage SF-MSCs cultured in MSCM-sf, such as CD73 (99.5%), CD90 (98.9%) and CD105 (96.5%), were more than 95%. However, the overall negative markers (CD34, HLA-DR and CD11b) expressed less than 2%. Three-way differentiation staining was positive. The combination of SF-MSCs and PGA / PLA can be induced into cartilage in vitro.@*Conclusions@#SF-MSCs cultured in MSCM-sf can be amplified under the condition of maintaining the stem cell characteristics, and can be combined with PGA/PLA scaffold to construct three-dimensional cartilage in vitro.
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<p><b>OBJECTIVE</b>To compare the tissue engineered cartilage constructed with chondrocytes derived from auricular and articular cartilage.</p><p><b>METHODS</b>Chondrocytes were isolated from porcine auricular and articular cartilage, and BMSCs were obtained from bone marrow aspirate and cultured. Each kind of chondrocytes were resuspended alone or mixed with BMSCs at a ratio of 1:1, and seeded onto PGA/PLA scaffolds to construct tissue engineered cartilage (n = 4). The constructs were cultured for 8 weeks in vitro and then subcutaneously implanted into nude mice for 6 weeks. The differences between chondrocytes monoculture from articular and auricular cartilage or between each of them co-cultured with BMSCs were evaluated by gross view, measurement of thickness and wet weight, histological examinations including H&E, Safranin O, type II collagen, and Ponceau's & Victoria blue staining, and gene expression analysis of cartilage related genes.</p><p><b>RESULTS</b>No obvious differences were found histologically among the complexes constructed in vitro 8 weeks except for few elastic fibers secreted in the auricular chondrocytes + BMSCs co-culture group. Neo-cartilage is thicker in the groups of articular chondrocytes (38. 1% than the group of auricular chondrocytes, P < 0.05) and articular chondrocytes + BMSCs co-culture (19.3% than the group of auricular chondrocytes + BMSCs, P < 0.05). However, after 6 weeks in vivo the elastic fibers were found positive in the complexes constructed by auricular chondrocytes, and its staining was even stronger and more homogenous in the group of auricular chondrocytes + BMSCs co-culture. The tissues generated by articular chondrocytes alone and co-cultured with BMSCs both formed the characteristic features of three-layer structure of hyaline cartilage and ossified in vivo with significant up-regulation of COL10A1 and MMP-13. To summarize, auricular chondrocytes formed the elastic cartilage while articular chondrocytes formed the hyaline cartilage during the development of tissue engineered cartilage either by monoculture or the co-culture with BMSCs.</p><p><b>CONCLUSIONS</b>The chondrogenic response of chondrocytes from different cartilage origins demonstrates that an initial chondrocyte and cartilage type recapitulates the same in later tissue-engineered development.</p>
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Animals , Bone Marrow Cells , Cell Biology , Cartilage, Articular , Cell Biology , Cells, Cultured , Chondrocytes , Coculture Techniques , Ear Auricle , Cell Biology , Mesenchymal Stem Cells , Cell Biology , Mice, Nude , Swine , Tissue Engineering , Methods , Tissue ScaffoldsABSTRACT
Objective To evaluate the correlation between the expression level of Nanog gene and clinical outcomes of GP regimen in the advanced non-small cell lung cancer (NSCLC).Methods 62 patients of NSCLC were treated by GP method,and the outcomes were investiged between Nanog positive and nagetive patients.The expression level of Nanong was evaluated by RT-PCR and immunohistology.Results 30 out of 62 patients (48.4 ％) were Nanog positive,9 patients (28.1％) were Nanog positive,and 23 out of 32 patients were Nanog negative (71.9 ％) who have the positive effect (CR+PR).However,among 32 treatment nagetive cases,there were 21 cases (70.0 ％) who were Nanog positive and 9 cases (30.0 ％) were Nanog negatve.Survival analysis showed that 5-years lifetime of Nanog positive patients was shorter than Nanong nagetive patients.Conclusion Nanog overexpression decreases the sensitivity of GP regimen and lifetime of NSCLC patient.Nanog expression level may provide a useful factor for clinical treatment and prognosis of NSCLC patient.
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BACKGROUND: Classic isolation method of bone marrow mesenchymal stem cells (BMSCs) is Percoll density gradient centrifugation. Blood cell component was removed. However, this method is complicated. Preparation density was needed when isolating dog bone marrow. Moreover, centrifugation was frequent, which had a great damage to cells. OBJECTIVE: To establish methods of the isolation, proliferation, culture and osteoinduction of canine BMSCs, and observe the in vitro proliferation and ability to osteoinduction differentiation. METHODS: 10 mL bone marrow was extracted from dog posterior superior iliac spine, heparin anticoagulation, diluted using Hanks juice, treated with 1.077 g/mL Ficoll solution 3 mL, and centrifuged at 2 000 r/min for 20 minutes. Karyocytes were absorbed to form white cloudlike layering interface, and then centrifuged twice using DMEM supplemented with fetal bovine serum, incubated at 12×10~4/cm~2 at 37 ℃ in a 5% CO_2 incubator. Following subculture, cells were incubated in DMEM containing dexamethasone, β-sodium phosphoglycerol and ascorbic acid 2-phosphate. Immunocytochemical staining and immunofluorescence staining were utilized to detect osteocalcin, osteopontin and type Ⅰ collagen expression in osteoblasts. Alkaline phosphatase staining and alizarin red staining were performed. RESULTS AND CONCLUSION: 1.077 g/mL Ficoll density gradient centrifugation was used to isolate karyocytes that were significant compared with Percoll solution. Obtained BMSCs had high purity, good growth and the mean doubling time was 24 hours. Following in vitro osteogenic incubation of dog BMSCs, osteocalcin, osteopontin and type Ⅰ collagen showed positive expression. Alkaline phosphatase staining demonstrated bluish-green cytoplasm. Alizarin red staining showed red nodes in extracellular matrix, and could differentiate into osteoblasts in vitro.
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Cartilage is one of the earliest reconstructed tissues used in tissue engineering. Due to the lack of appropriate seeding cells, cartilage tissue engineering is, however, relatively lagged behind. With the emergence of stem cell research, adipose stem cells(ASCs) are introduced as seeding cells into tissue engineering for possessing many advantages such as wide spreading, large amount of cells available and easy to obtain. However, the outcome of tissue engineered cartilage construction by ASCs is not as ideal as that by bone marrow stem cells (BMSCs) yet. Low efficiency of ASC chondrogenesis is considered the major cause. This review summarizes the purification of adipose-derived cells, maintenance of sternness and optimization of ehondrogenie induction, which play vital roles in improving ASC s chondrogenesis.
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Autologous cells of bone, cartilage, intervertebral disc and tendon, are hard to be cultured and proliferate in vitro and thus have difficulty to be introduced in the repair of damaged tissue. Stem cells have the ability to self-renew and differentiate into many tissue types. Recent progress in stem cell research has led to an enthusiastic effort to utilize stem cells for orthopaedic tissue regeneration. Due to the abundance and easiness of harvest, adipose-derived mesenchymal celI(ASC) is an attractive, readily available aduh stem cell that has become increasingly popular for use in stem cell and tissue engineering applications. This review focuses on the use of ASC in orthopaedic tissue repair. Recent results from in vivo defect repair utilizing ASC suggested the great potential of ACS in clinical orthopaedic tissue regeneration.
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BACKGROUND: There are plentful studies about bioreactor of tissue engineering of blood vessel, tendon, cartilage, heart valve,trachea, bladder and stern cell. OBJECTIVE: To construct small-sized tissue-engineerad blood vessels with human bone marrow stromal stem cells (hBMSCs) in improved bioreactor system.DESIGN, TIME AND SETTING: The single sample observation stuay was performed at the School of Mechanical and Power Engineering, East China University of Science&Technology, and Shanghai Tissue Engineering Research & Development Center from June 2005 to March 2008.MATERIALS: Vessel bioreactor was self-made by East China University of Science&Technology. hBMSCs were harvested from healthy volunteers. METHODS: A set of support bracket constructing tissue engineered blood vessels with the diameter of 2 mm was designed with the application of Finite Element Methods as an analysis method analyzing support bracket of tissue engineered small-sized blood vessel. Primary hBMSCs were first Collected and further cultivated exvivo. The third passage cultured cells were then seeded on the polyglycolic acid (PGA) to fabricate the cell-scaffold composite. Subsequently, this composite was subjected to dynamical culture in the blood vessel bioreactor. After cultured for 4 weeks, the composite was removed from the bioreactor.MAIN OUTCOME MEASURES: The following mentioned references were measured: composite growth; other correlation detection of the hBMSCs-PGA composite, RESULTS: Gross observation and scanning electron microscope were used at4 weeks after hBMSCs-PGA composite culture. It was observed that the tissue-engineered blood vessel had a bright color and certain elasticity. The blood vessel could rebound to its odginal shape after repeated press by the forceps.The secreted collagen matrix arrayed orderly around the cells and smooth muscle elastic acttn could also be detected in the formed tissues using immunohistochemistry. CONCLUSION: The in vivo mechanics conditions of blood vessels can be simulated using the current blood vessel bioreactor system. Using hBMSCs, the construction of tissue engineered small-sized blood vessels can be successfully achieved.
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BACKGROUND: A lot of researches have proved that polyglicolide acid (PGA), as a stent material, has been successfully used to construct engineered tissues, such as cartilage, bone and tendons, in nude mice or even big mammal. Whether the incubation of vascular endothelial cells and smooth muscle cells in the polyglicolide acid may subcutaneously construct vessel-like structure in nude mice needs a further study.OBJECTIVE: To verify the feasibility of forming vessel-like structure in the nude mice by subcutaneous implantation of polyglicolide acid cocultured with vascular endothelial cells and smooth muscle cells derived from newborn umbilical vein.DESIGN: Contrast study.SETTING: Tissue Engineering Key Laboratory, Medical College, Shanghai Jiao Tong University.MATERIALS: This study was performed at Tissue Engineering Key Laboratory, Medical College, Shanghai Jiao Tong University from January to June 2002. Belly band was derived from newborn babies in our department of obstetrics & gynecology. The parturien provided the informed consent, and this study was approved by the local research ethics committee. Twenty-six nude mice (3-4 weeks old, clean grade, irrespective of gender) were selected in this study. The animal experiment received confirmed consent from the local ethic committee. Polyglicolide acid was provided by Albany International Research Co.METHODS: Vascular endothelial cells and smooth muscle cells derived from newborn umbilical vein were incubated on a piece of polyglicolide acid to produce cell-material compound. In addition, the compound covered around the silicone tube to form a tube-like structural substance. Subsequently, the tube-like structural substance was subcutaneously implanted in 20 nude mice, which were regarded as an experimental group. And then, polyglicolide acid alone was subcutaneously transplanted in the rest 6 nude mice, which was regarded as a control group.MAIN OUTCOME MEASURES: Gross observations of cell-material compound by 2 and 6 weeks after transplantation;HE staining and immunohistochemical staining.detection; expression of factor Ⅷ and α-smooth muscle actin.RESULTS: Twenty-six nude mice were included in the final analysis. ① Gross observation: At 2 weeks after implantation,both the experimental and control groups formed tubular structures, however, at 6 weeks after implantation, the tubular structure still remained in experimental group but not in the controls. ② Histological observation and immunohistochemical detection: The histological examination of the engineered vessel showed that at 2 weeks, the vessels in both group contained mainly undegraded PGA fibers, while at 6 weeks, the PGA fibers were almost completely degraded in both groups and in the control group only fibrous-like tissue formed. Contrastly, in experimental group a typical vascular structure formed, Masson's trichrome stain, which stains collagen green, smooth muscle fibers red and cells purple, showed significant amounts of stainable collagen and smooth muscle fibers in the wall of the engineered vessel, furthermore,immunohistochemistry examination revealed that there were an endothelial cell layer formed in the inner surface of the engineered vessel which was confirmed by positive staining of yon Willebrand factor, meanwhile, the smooth muscle cells in the wall of the engineered vessel were confirmed by the positive staining of smooth muscle α-actin.CONCLUSION: The subcutaneous implantation of polyglicolide acid cocultured with vascular endothelial cells and smooth muscle cells may form vessels, which are similar to normal vascular histological structure.
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@#Objective To investigate the action of chondrogenesis differentiation of bone marrow stromal cells (BMSCs) transfected with adeno-hTGF-β1. Methods In the experiment group, replication-deficient a denoviruses carrying human hTGF-β1 complementary DNA (adeno-hTGF-β1 was constructed and applied to transfect to the first generation BMSCs. As a control, each BMSCs was transduced with 200 pfu of adeno-LacZ gene. One day after transfer, BMSCs were trypsinized, counted, and 5×105 cells aliuots were spun down at 500 rpm per minute in 15 ml polypropylene conical tubes and then cultured in a defined medium in an incubator at 37℃ for 21 days. The aggregates were harvested at time points to 21 days and assessed by gross observation, histological analyses and immunohistochemical localization of type Ⅱ collagen. Results When harvested at 21 days, each pellet shrinked to spheroid tissue with apearly opalescence in gross morphology and found to be relatively firm. H.E staining showed elongate dlining cells appeared as perichon drium-like cells at the surface. Some nests of cartilage were observed at the substrate of the tissue. Mature chon drocytes were embeded in the lacuna in the experiment group. In addition, Safranin'O staining confirmed the presence of sulfated proteoglycans in the ECM of chondrogenesis region. Immunohistochemical staining revealed the presence of type Ⅱ collagen in chondrogenesis region. By contrast, HE staining showed no evidence of cartilage formation in the control group. They were fibrous tissue with no architectural feature. Safranin'O staining and Immunohistochemical staining showed no evidence of sulfated proteoglycans or typeⅡ collagen expression. Conclusion BMSCs transfected with adeno-hTGF-β1 could induce its chondro-genesis when aggregate cultured in a defined medium in vitro, laying a foundation for the application of hTGFβ1 gene-transfected BMSCs in cartilage tissue engineering.
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In order to prepare three-dimensional scaffolds with "ideal pore-structure" for tissue engineering, a novel water dissoluble adhesive was developed, and the property of adhesive as well as influence of experimental condition on bonded porogen assembly was investigated. Experimental results showed that it was possible to fabricate large dimensional porogen assembly with homogenous and controllable bonding extent by this adhesive, and a large dimensional (45 mm in diameter, 55mm in thickness) biodegradable poly(D,L-lactic acid)(PDLLA) scaffold resulting from bonded porogen was formed. The scaffolds with high porosity as well as with controllable and homogeneous inner-structure can be easily formed. In addition, pore size of scaffolds as well as diameter of openings can be controlled by adjusting the porogen size and bonding degree in bonded porogen assembly.
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Adhesives , Chemistry , Lactic Acid , Chemistry , Polyesters , Polymers , Chemistry , Porosity , Solubility , Surface Properties , Tissue Engineering , Tissue Scaffolds , ChemistryABSTRACT
BACKGROUND: The transplantation of allogeneic cartilage has local immunological rejection, and it is necessary to further reduce the rejection to promote its application in clinic, thus it is significant to perform a series of experiments to induce local immune privilege.OBJECTIVE: To observe the in vivo growth of tissue engineered allogeneic cartilage reconstructed by chondrocytes transfected with recombinant retroviral vector pLNCX2-FasL.DESIGN: A randomized controlled observation.SETTING: Shanghai Jiao Tong University.MATERIALS: Thirty-six allogeneic New Zealand rabbits as recipients and 45 1-week-old chinchillas as donors, either sex,were purchased by the experimental animal center of Chinese Academy of Sciences. Amphotropic recombinant retrovirus coated cell line PT67 was purchased from Clontech Company; Dulbecco's modified eagle medium (DMEM), fetal bovine serum (FBS), G418 and Polybrene were bought from GIBCO BRL.METHODS: The experiment was carried out in original Shanghai Second Medical University from January 2000 to July 2005. The New Zealand rabbits were randomly divided into three groups: FasL-transfected group (n =12), untransfected group (n =12) and blank control group (n =12). The rabbit allogeneic cartilages were constructed by the compound of pLNCX2-FasL transfected chondrocytes and tissue engineered material of pluronic F-127. ① Gross observation and mass changes of the grafts: Corresponding materials were infused subcutaneously, the grafts were removed at 1, 2 and 3 months after transplantation for gross observation and the mass changes. ② Staining observation: The grafts were removed at 1, 2 and 3 months after transplantation, then prepared into sections, and observed by hematoxylin and eosin (HE), Safranin'O and Masson's trichrome stainings. ③ Antibody detection: Blood samples (1 mL) were collected at 1 and 2 months after transplantation, the chondrocytes of the chinchillas were lysed freezingly with lysis antigen as the mixed antigen, and separated by electrophoresis in agarose medium, then acted with serum of recipient to observe whether corresponding antibody generated. ④ Complement dependent cytotoxicity (CDC) test: The chondrocytes of chinchillas were prepared into cell suspension (2×109/L), and then seeded into 96-well plate, attached grew for 24 hours, then recipient serum was added for the CDC test, and the percentage of apoptotic cells was counted under microscope.MAIN OUTCOME MEASURES: ① Gross observation and mass changes of the grafts;② Histological changes; ③ Results of the antibody detection; ④ Percentage of apoptotic cells.RESULTS: All the 81 rabbits were involved in the analysis of results. ① Gross observation and mass changes of the grafts: Two weeks after inoculation, there were obvious nod formations at the inoculated sites, but no nod formed in the blank control group. The new cartilage tissues became smaller gradually and completely disappeared at 4 months in the untransfected group, whereas those in the FasL-transfected group became smaller, but still existed after 7 months. The masses of grafts in the FasL-transfected group were higher than those in the untransfected group (P ＜ 0.05). ②Histological observation: Plenty of lymphocytic infiltrations around cartilage tissue could be observed in the untransfected group, and obviously decreased in the FasL-transfected group. No lymphocyte was observed inside the chondrocytes.Masson's trichrome staining was performed, and it was observed under light microscope that the small white parts in the middle were immature chondrocytes, and there were green collagen around most of the mature chondrocytes. Safranin O staining showed strong positive reaction, suggested that there were rich glycosaminoglycan in matrix. ③ Antibody detection: The chondrocytes of the chinchillas were lysed freezingly with lysis antigen as the mixed antigen, then acted with serum of recipient, and the results showed that no corresponding antibody generated. ④ Percentage of apoptotic cells: The percentages of serum CDC apoptotic cells in the FasL can ransfected group, untransfected group and blank control group were 5%, 6% and 1%, which were all negative.CONCLUSION: Rabbit allogeneic chondrocytes transfected with recombinant retroviral vector pLNCX2-FasL can reconstruct tissue engineered cartilage, and can postpone the degeneration by 3 months.
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The recombinant human Smad7 adenoviral vector was constructed by direct DNA cloning protocol and then transfected into 293 cells for virus packaging. After amplification and purification, the recombinant adenovirus was used to infect the keloid fibroblasts. The Smad7 mRNA transcription of the infected cells was detected by RT-PCR. The recombinant Adeno-Smad7 was correctly constructed and confirmed by both restriction analysis and PCR analysis. RT-PCR showed the over expression of adenovirus mediated Smad7 mRNA in keloid cells. These results demonstrated that the recombinant Smad7 adenoviral vector can be expressed in cultured cells in vitro, and it may provide a new therapeutic strategy for keloid gene therapy.
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Humans , Adenoviridae , Genetics , Metabolism , Cells, Cultured , Fibroblasts , Metabolism , Pathology , Genetic Vectors , Genetics , Metabolism , Keloid , Metabolism , Pathology , RNA, Messenger , Genetics , Recombinant Fusion Proteins , Genetics , Smad7 Protein , Genetics , TransfectionABSTRACT
Objective To investigate the effects of cryopreservation on the growth and osteogenesis capa- bility of human bone marrow stromal cells(BMSCs)on demineralized bene matrix(DBM).Methods Bone marrow aspirates were obtained from the lilac crests of three donors.The BMSCs were isolated from the bone marrow by density gradient centrifugation.Cells of passage 3 were cryopreserved in liquid nitrogen for 24 hours,and then re- covered.The non-cryopreserved BMSCs were used as the control,The cryopreserved and control BMSCs were cul- tured in osteogenic media,collected and labeled with Dil to be seeded onto the DBM when cells were confluent.The percentage of BMSCs adhered to the DMB was detected.The cell morphology and matrices secreted by BMSCs on the DBM were observed by the inverted phase-contrasted microscope,fluorescence microscope and scanning electron microscope(SEM).The growth and viability of BMSCs on the DBM were determined using the modified MTT ashy. The osteogenesis ability of BMSCs on the DBM was determined by assessment of the alkaline phosphatase(ALP) activity and osteocalcin(OCN)content.Results The percentages of the cryopreserved and control cells adhered to DBM were(97.25?1.17)% and(97.00?1.09)% respectively.The cells adhered well to the DBM and grew rapidly.Large amounts of matrices on the DBM were observed by the light microscope and SEM.The cells embedded in the matrices could be observed by fluorescence microscope.There were no significant differences in the assay values of MTT,ALP and OCN between the cryopreserved and control BMSCs on the DBM.Conclusion Since cryopreservation does not affect the growth and osteogenesis capability of BMSCs on DBM,the cryopreserved BMSCs can be used as a cell source in bone tissue engineering.
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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
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<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>
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Animals , Female , Male , Fibroblasts , Physiology , Polyglycolic Acid , Pharmacology , Skin Transplantation , Skin, Artificial , Swine , Tissue EngineeringABSTRACT
<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>
Subject(s)
Humans , Activin Receptors, Type I , Pharmacology , Cells, Cultured , Down-Regulation , Fibroblasts , Metabolism , Gene Expression , Keloid , Metabolism , Protein Serine-Threonine Kinases , RNA, Messenger , Genetics , Metabolism , Receptors, Transforming Growth Factor beta , Metabolism , Sensitivity and Specificity , Signal Transduction , Trans-Activators , Metabolism , Up-RegulationABSTRACT
<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>
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Animals , Bone Marrow Cells , Physiology , Cell Differentiation , Cells, Cultured , Chondrocytes , Physiology , Collagen Type II , Genetics , Phenotype , RNA, Messenger , Stem Cells , Physiology , Swine , Tissue Engineering , Transforming Growth Factor beta , PhysiologyABSTRACT
Cutaneous wounding in adult humans and higher vertebrate animals results in scar formation. In contrast, both human and animal fetuses, at early gestational ages, exhibit skin wound healing without scarring. This distinction suggests that the repair of adult wounds by skin regeneration, rather than by fibrosis, may be achieved if adult wounds can be modified to mimic the healing process of fetal wounds. The development of gene therapy offers the possibility to specifically enhance or block the gene expression of cytokines and extracellular molecules, and thus convert adult wound healing into a healing process more similar to tissue regeneration. This article reviews the characteristics of fetal wound repair focusing on cytokine profiles and the inflammatory response to dermal injury. Also included are new developments in gene transfer techniques as well as their application in wound healing. Finally, the authors propose possible strategies of wound gene therapy, to reduce wound scarring and to promote tissue regeneration.
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Humans , Animals , Cicatrix/prevention & control , Fetus/physiology , Genetic Therapy , Wound Healing/physiologyABSTRACT
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