Optimization of cultivation condition of recombinant E. coli DH5 alpha/pDH-B2m and the condition suitable for expression of recombinant mature peptide of human bone morphogenetic protein-2 was carried out in 500 mL shaking flasks and then transferred to NBS Bioflo IV, a 20 L DO feed-back fed-batch culture system, to obtain rhBMP-2. The results indicate that keeping dissolved oxygen at 40% and controlling nutrient feeding rate with DO feed back strategy can obtain theoretically 3.59 g recombinant mature peptide of hBMP-2 per liter of broth, the final cell density OD600 reaches 57(22.8 g dry cell weight/L), and the expression of rhBMP-2 amounts to 30% of the total protein in E. coli.
Bone Morphogenetic Protein 2 ; Bone Morphogenetic Proteins ; biosynthesis ; genetics ; Culture Media ; Escherichia coli ; genetics ; Fermentation ; Glycerol ; pharmacology ; Recombinant Proteins ; biosynthesis ; Time Factors ; Transforming Growth Factor beta

OBJECTIVE: To construct the recombined retroviral expression vector of BMP2/pLEGFP and investigate the bio-activity of the expressed chimeric protein. METHODS: The recombinant vector constructed by gene recombinant technology was analyzed by restriction enzyme digestion and PCR. BMP2/pLEGFP was transfected into COS-7 cells with liposome transfection reagents for transient expression. The expression of chimeric protein BMP2/EGFP was identified by fluorescent microscope and Western blotting. The bio-activity was examined by the cellular activity and animal heterotopic osteogenesis experiment. RESULTS: The recombinant plasmid proved successful by restriction enzyme digestion and PCR. The expression of the chimeric protein was shown by fluorescent microscope and Western blotting. The chimeric protein had the double bio-activities of BMP2 and EGFP identified by the cellular activity and animal heterotopic osteogenesis tests. CONCLUSION The recombinant vector of BMP2/pLEGFP is successfully constructed by the gene recombinant technology and its chimeric protein has double bioactivities of BMP2 and EGFP.
Animals ; Bone Morphogenetic Protein 2 ; Bone Morphogenetic Proteins ; biosynthesis ; genetics ; COS Cells ; Chlorocebus aethiops ; Eukaryotic Cells ; metabolism ; Green Fluorescent Proteins ; biosynthesis ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Transfection ; Transforming Growth Factor beta ; biosynthesis ; genetics

OBJECTIVETo determine the expression of bone morphogenetic protein 2 and 4 (BMP-2 and BMP-4) in prostatic carcinoma (PCa) and investigate their relationship with clinical stage and Gleason score of tumor.

METHODSForty-eight PCa cases and 5 normal prostatic tissue were analysed for the expressions of BMP-2 and BMP-4 by Western bolt assay.

RESULTSThe optical densities of BMP-2 expressions in the tumor with Gleason score < or =5, 6-8, and > or = 9 were 7547.1 +/- 1964.12, 9657.4 +/- 2010.54, 12467.7 +/- 2496.75 and of BMP-4 expressions were 5174.4 +/- 1400.54, 5940.3 +/- 1587.42, 6332.1 +/- 1647.83, respectively. The optical densities of BMP-2 expressions in the tumor in T1 - T2 and T3 - T4 stages were 8003.37 +/- 1889.23, 12385.55 +/- 2506.72 and of BMP4 expressions were 5267.41 +/- 1 464.19, 6543.75 +/- 1668.46, respectively. There were significant differences between tissues with Gleason score < or =5 and > or =9 (P <0.01), and tissues in T1 - T2 and T3 - T4 stages, in expressions of BMP-2 protein. The expression of BMP-2 protein was significantly high in the PCa with bone metastasis compared with that without bone metastasis.

CONCLUSIONThe expressions of BMP-2 and BMP-4 increase with the progression of clinical stage and Gleason score compared with normal prostatic tissue. The expression of BMP-2 protein is significantly upregulated in bone metastasis of PCa, which indicates a poor prognosis.

Aged ; Aged, 80 and over ; Blotting, Western ; Bone Morphogenetic Protein 2 ; Bone Morphogenetic Protein 4 ; Bone Morphogenetic Proteins ; biosynthesis ; Humans ; Male ; Middle Aged ; Neoplasm Metastasis ; Neoplasm Staging ; Prostate ; metabolism ; Prostatic Neoplasms ; metabolism ; pathology ; Transforming Growth Factor beta ; biosynthesis

OBJECTIVETo express and purify the recombinant human bone morphogenetic protein-2 mature peptide (rhBMP-2m) in prokaryotic system and to develop highly-specific monoclonal antibodies.

METHODSAn engineered E. coli strain expressing rhBMP-2m was fermented. The bacterial cells were firstly lysed and then the rhBMP-2m inclusion bodies were isolated by centrifugation. After the inclusion bodies had been solubilized by high-concentration denaturing agents, denatured rhBMP-2m was purified by cation ion-exchange chromatography. Biologically active rhBMP-2m was obtained by refolding of purified denatured rhBMP-2m through direct dilution. The refolded rhBMP-2m was used to immunize Balb/c mice to develop anti-rhBMP-2m monoclonal antibodies using classic hybridoma technique.

RESULTSrhBMP-2m with a purity greater than 95% was obtained on reduced SDS-PAGE. The refolded rhBMP-2m was measured to be bioactive by the induction of alkaline phosphatase activity in MC3T3-E1 cells. Two hybridoma cell lines that stably secreted anti-rhBMP-2m antibody were developed from the immunized mice.

CONCLUSIONBioactive rhBMP-2m protein and its monoclonal antibodies were successfully prepared, which will provides a solid base for future studies on rhBMP-2.

Animals ; Antibodies, Monoclonal ; biosynthesis ; Bone Morphogenetic Proteins ; biosynthesis ; immunology ; Escherichia coli ; metabolism ; Humans ; Mice ; Mice, Inbred BALB C

In order to investigate the possibility of expression of exogenous gene in transduced articular chondrocytes, plasmid pcDNA3-rhBMP7 was delivered to cultured chondrocytes. Through immunohistochemical staining and RT-PCR assay, the expression of rhBMP7 gene was detected. And the bioactivity of transgene expression product was detected through MTT assay as well. It was confirmed that exogenous gene could be expressed efficiently in transduced chondrocytes and the transgene expression product had obvious bioactivity. The present study provided a theoretical basis for gene therapy on the problems of articular cartilage.
Animals ; Bone Morphogenetic Protein 7 ; Bone Morphogenetic Proteins ; biosynthesis ; genetics ; Cartilage, Articular ; metabolism ; Chondrocytes ; metabolism ; Gene Expression ; Rabbits ; Recombinant Proteins ; biosynthesis ; genetics ; Transfection ; Transforming Growth Factor beta ; biosynthesis ; genetics ; metabolism

OBJECTIVETo explore the possibility of expression of exogenous gene in transduced bone marrow derived stromal cells (BMSCs).

METHODSThe marker gene, pbLacZ, was transferred into cultured BMSCs and the expression of transduced gene by X-gal staining was examined. Then plasmid pcDNA3-rhBMP7 was delivered to cultured BMSCs. Through immunohistochemical staining and RT-PCR assay, the expression of rhBMP7 gene was detected.

RESULTSThe exogenous gene could be expressed efficiently in transduced BMSCs.

CONCLUSIONThe present study provided a theoretical basis to gene therapy on the problems of bone and cartilage tissue.

Animals ; Bone Marrow Cells ; cytology ; metabolism ; Bone Morphogenetic Protein 7 ; Bone Morphogenetic Proteins ; biosynthesis ; genetics ; Cells, Cultured ; Genetic Vectors ; genetics ; Rabbits ; Recombinant Proteins ; biosynthesis ; Stromal Cells ; cytology ; metabolism ; Tibia ; cytology ; Transfection ; Transforming Growth Factor beta

OBJECTIVETo investigate the probabilities of core-biding factor a1 (Cbfa1) expression by human skin fibroblasts induced in vitro.

METHODSThe fibroblasts were isolated, purified from human skin, and were grown in incubation in the media of TNF-alpha, BMP-2, and combined TNF-alpha and BMP-2 at certain concentrations, respectively. The changes in biological features of these fibroblasts correlated with osteogenesis were detected by immunohistochemistry and RT-PCR assay.

RESULTSTNF-alpha could switch phenotype of collagen in fibroblasts from Type I and III to Type I and induce fibroblasts to express Ras and BMP type I receptor (BMPR-IA). TNF-alpha in combination with BMP-2 could induce fibroblasts to express Cbfa1 and osteocalcin mRNA.

CONCLUSIONHuman skin fibroblast could be induced into pro-osteoblast expressing Cbfa1, an osteoblast-specific transcription factor and a regulation of osteoblast differentiation, and combined use of TNF-alpha and BMP-2 was one of the regulating factors.

Bone Morphogenetic Protein 2 ; Bone Morphogenetic Protein Receptors, Type I ; Bone Morphogenetic Proteins ; pharmacology ; Cells, Cultured ; Collagen ; biosynthesis ; Core Binding Factor Alpha 1 Subunit ; Core Binding Factors ; Fibroblasts ; metabolism ; Humans ; Neoplasm Proteins ; Osteocalcin ; biosynthesis ; Protein-Serine-Threonine Kinases ; biosynthesis ; RNA, Messenger ; analysis ; Receptors, Growth Factor ; biosynthesis ; Skin ; cytology ; Transcription Factors ; biosynthesis ; genetics ; Transforming Growth Factor beta ; Tumor Necrosis Factor-alpha ; pharmacology

Understanding limb development not only gives insights into the outgrowth and differentiation of the limb, but also has clinical relevance. Limb development begins with two paired limb buds (forelimb and hindlimb buds), which are initially undifferentiated mesenchymal cells tipped with a thickening of the ectoderm, termed the apical ectodermal ridge (AER). As a transitional embryonic structure, the AER undergoes four stages and contributes to multiple axes of limb development through the coordination of signalling centres, feedback loops, and other cell activities by secretory signalling and the activation of gene expression. Within the scope of proximodistal patterning, it is understood that while fibroblast growth factors (FGFs) function sequentially over time as primary components of the AER signalling process, there is still no consensus on models that would explain proximodistal patterning itself. In anteroposterior patterning, the AER has a dual-direction regulation by which it promotes the sonic hedgehog (Shh) gene expression in the zone of polarizing activity (ZPA) for proliferation, and inhibits Shh expression in the anterior mesenchyme. In dorsoventral patterning, the AER activates Engrailed-1 (En1) expression, and thus represses Wnt family member 7a (Wnt7a) expression in the ventral ectoderm by the expression of Fgfs, Sp6/8, and bone morphogenetic protein (Bmp) genes. The AER also plays a vital role in shaping the individual digits, since levels of Fgf4/8 and Bmps expressed in the AER affect digit patterning by controlling apoptosis. In summary, the knowledge of crosstalk within AER among the three main axes is essential to understand limb growth and pattern formation, as the development of its areas proceeds simultaneously.
Animals ; Apoptosis ; Body Patterning ; Bone Morphogenetic Proteins/biosynthesis* ; Developmental Biology ; Ectoderm/metabolism* ; Extremities/embryology* ; Fibroblast Growth Factor 10/metabolism* ; Fibroblast Growth Factors/biosynthesis* ; Gene Expression Regulation ; Hedgehog Proteins/biosynthesis* ; Homeodomain Proteins/biosynthesis* ; Mesoderm/metabolism* ; Mice ; Signal Transduction ; Wnt Proteins/biosynthesis*

OBJECTIVETo study the effects of epimedium pubescens icariine on the proliferation and differentiation of human osteoblasts.

METHODHuman osteoblasts were obtained by inducting human marrow mesenchymal stem cells (hMSCs) directionally. MTT was used to observe the proliferation and activity of ALP was assayed to observe the differentiation of the third passage human osteoblasts cultured in vitro. The expression of BMP-2 mRNA was checked by RT-PCR.

RESULTEpimedium pubescens icariine at the dose of 20 microg x mL(-1) increased greatly the proliferation and differentiation of human osteoblasts and promoted the expression of BMP-2 mRNA.

CONCLUSIONEpimedium pubescens icariine enhances significantly the proliferation and differentiation of human osteoblasts, which may be mediated by increasing the expression of BMP-2 mRNA.

Bone Morphogenetic Protein 2 ; Bone Morphogenetic Proteins ; biosynthesis ; genetics ; Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Epimedium ; chemistry ; Flavonoids ; isolation & purification ; pharmacology ; Humans ; Osteoblasts ; cytology ; Plants, Medicinal ; chemistry ; RNA, Messenger ; biosynthesis ; genetics ; Transforming Growth Factor beta ; biosynthesis ; genetics

OBJECTIVEBone marrow stromal cells (MSCs) were transfected with human bone morphogenetic protein-4 (hBMP-4) gene in vitro to provide BMP gene modified cells for tissue-engineered bone.

METHODSMSCs were cultured and transfected with pEGFP-hBMP4, pEGFP plasmids respectively or left uninfected as control. Transcription of BMP-4 gene as well as gene transfection efficiency was tested. Morphological and growth feature of the transfected cells were valued. Alkaline phosphatase (ALP), von Kossa, and Osteocalcin (OC) were tested to determine the phenotypes of osteoblast.

RESULTSThe gene transfection efficiency was 20%-30%, based on GFP expression. RT-PCR showed that MSCs had low transcription of BMP-4 that was enhanced by the gene transfer. Morphological feature of MSCs transfected with pEGFP-hBMP-4 changed but growth curves did not show much difference among the groups. In pEGFP-hBMP-4 group, ALP positive stain area and the number of calcium nodules were increased, as well as the expression of OC.

CONCLUSIONSA high transfer efficiency of MSCs was achieved under optimized conditions. The gene transfer technique strengthened the transcription of BMP-4 and promoted differentiation from MSCs to osteoblasts. hBMP-4 transferred MSCs may serve as an ideal cell source for tissue-engineered bone.

Animals ; Bone Marrow Cells ; cytology ; Bone Morphogenetic Protein 4 ; Bone Morphogenetic Proteins ; biosynthesis ; genetics ; Cell Differentiation ; Cells, Cultured ; Gene Transfer Techniques ; Osteoblasts ; cytology ; metabolism ; Osteocalcin ; biosynthesis ; genetics ; Osteogenesis ; Rabbits ; Stromal Cells ; cytology ; Tissue Engineering ; Transfection