Comparison of three types of chondrocytes in collagen scaffolds for cartilage tissue engineering.

The objective of this study was to compare the chondrogenesis in type I and II collagen scaffolds seeded with chondrocytes from three types of cartilage, after four weeks of culture: auricular (AU), articular (AR) and meniscal (ME). Related aims were to investigate the expression of a contractile muscle actin isoform, alpha-smooth muscle actin (SMA), in the cells in the scaffold and to determine the presence of a lubricating glycoprotein, lubricin, in the constructs. Adult goat AU, AR and ME chondrocytes were seeded into two types of collagen scaffolds: type II collagen and type I/III collagen.

Adenoviral transduction of hTGF-beta1 enhances the chondrogenesis of bone marrow derived stromal cells.

TGF-beta1 plays a necessary and important role in the induction of chondrogenic differentiation of bone marrow stromal cells (BMSCs). In this study, porcine BMSCs were infected with a replication-deficient adenovirus expression vector carrying the hTGF-beta1 gene. The transduced BMSCs were cultured as pelleted micromasses in vitro for 21 days, seeded onto disk-shaped PGA scaffolds for 3 days and subsequently implanted into the subcutaneous tissue of mice.

[Microarray analysis of dedifferentiation related gene expression of human chondrocytes cultured in vitro].

Objective: Dedifferentiation of chondrocytes during in vitro expansion is the major cause that limits the potential of chondrocytes for cartilage engineering. This study dissected dedifferentiation mechanism of in vitro cultured human chondrocytes by microarray analysis of gene expression changes.

Methods: Spare human costal cartilage from ear reconstruction patients (n=3, aged 10-20) were digested with collagenase II to isolate human chondrocytes(HCC) and were expanded from P1 to P4.

[Repair alveolar cleft bone defects with bone marrow stromal cells].

Objective: To explore the feasibility of repairing alveolar cleft bone defects with bone marrow stromal cells.

Methods: Total 7 patients of alveolar cleft were included in this study. The hBMSCs were isolated by percoll gradient centrifugation from patient's bone marrow aspirated from iliac crest.

Repair of tendon defect with dermal fibroblast engineered tendon in a porcine model.

Harvesting autologous tenocytes for tendon engineering may cause secondary tendon defect at the donor site. Dermal fibroblasts are an easily accessible cell source and do not cause major donor site defect. This study aims to explore the possibility of tendon engineering using dermal fibroblasts.

Tissue-engineered bone repair of goat-femur defects with osteogenically induced bone marrow stromal cells.

Tissue engineering can generate bone tissue and has been shown to provide a better means of repairing weight-bearing bone defect. Previous studies, however, have heretofore been limited to the use of nonosteogenically induced bone marrow stromal cells (BMSCs) or the application of slow-degradation scaffolds. In this study, weight-bearing bone was engineered using osteogenically induced BMSCs.

[Effect of adeno-BMP7 transfection on osteogenesis of BMSCs].

Objective: To study the effect of adeno-BMP7 transfection on the biology of bone marrow stromal cells (BMSCs).

Methods: Bone marrow was obtained from the goat. The BMSCs were isolated and cultured at the second passage.

[Experimental study of porous TCP to generate tissue-engineered long bone].

To study bone-forming of a new kind of porous beta-TCP as the scaffold for tissue-engineering, defects at the mid-portion of the left and right ulna were created in dog, the defects were repaired with beta-TCP cylinder coated with BMSCs, and beta-TCP cylinders alone as control. X-rays showed the defects were better bridged by the replant with obscure edge and new bone formed in the canal and at the interface in experimental group after three month of operation, whereas in control group, the replants were obviously deformed into dissociated granule with unequal density with only little new bone formed at the interface. After six month, the defects were bridged by new bone with osteodermatous cavum medullare ossium, but in control group, the defects were bridged by high density in radiography without osteodermatous cavum medullare ossium, the diameter of the ular was obviously less than experimental group.

Inhibiting scar formation in rat wounds by adenovirus-mediated overexpression of truncated TGF-beta receptor II.

The purpose of this study was to explore the possibility of inhibiting wound scarring by blocking TGFbeta signaling of wound cells by means of a gene therapy approach. Normal dermal fibroblasts were infected in vitro either with recombinant adenovirus encoding a truncated TGFbeta receptor II (Ad-tTGF-betaRII) or with [beta]-galactosidase adenovirus (Ad-beta-gal). TGF-beta1 gene expression in infected fibroblasts was analyzed by Northern blot.

[Clinical application of tissue engineered bone repair of human craniomaxillofacial bone defects].

Objective: To explore the feasibility of tissue engineered bone formation in human being using human bone marrow stromal cells (hBMSCs) and the possibility of clinical repair of craniomaxillofacial bone defects with tissue engineered bone.

Methods: Total 11 patients of cranial defects and aperture piriformis bone depression were included in this study. The hBMSCs were isolated by Percoll gradient centrifugation from patient's bone marrow aspirated from iliac crest.

A closer view of tissue engineering in China: the experience of tissue construction in immunocompetent animals.

Tissue engineering started in late 1980s and is now well established and progressing rapidly in Western developed countries. However, the development of tissue-engineering research in China remains relatively unknown to the international society of tissue engineering. Although involved in all areas of tissue-engineering research, including the creation of new scaffold materials, in vitro studies of seed cells, application of growth factors, and modification of seed cells and scaffold materials, China has put special emphasis on tissue construction in large mammalian animals in order to establish a solid scientific basis for clinical application of engineered tissues.

Tissue-engineered bone repair of sheep cranial defects with autologous bone marrow stromal cells.

Cranial bone defect remains a major challenge to craniofacial surgeons because of limited availability of autologous bone graft to repair the defects and the donor site defects secondary to tissue harvesting. In contrast, tissue-engineering technique can generate a large bone tissue using small amount of autologous cells and therefore avoid these problems. Bone Marrow Stromal Cells (MSCs) have the potential of multi-lineage (including osteogenic) differentiation.