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1.
Kam-Tsun Tang Casey Capparelli Janet L. Stein Gary S. Stein Jane B. Lian Anna C. Huber Lewis E. Braverman William J. DeVito 《Journal of cellular biochemistry》1996,61(1):152-166
Fibroblast growth factors (FGF) are osteoblast mitogens, but their effects on bone formation are not clearly understood. Most in vitro studies examining the effects of FGFs on osteoblasts have been performed only during the initial proliferative stage of osteoblast culture. In these studies, we examined the consequential effect of acidic FGF in cultures of rat fetal diploid osteoblasts that undergo a developmental differentiation program producing a mineralized bone-like matrix. During the initial growth period (days 1–10), addition of acidic FGF (100 μg/ml) to actively proliferating cells increased (P < 0.05) 3H-thymidine uptake (2,515 ± 137, mean ± SEM vs. 5,884 ± 818 cpm/104 cells). During the second stage of maturation (days 10–15), osteoblasts form multilayered nodules of cells and accumulate matrix, followed by mineralization (stage 3, days 16–29). Addition of acidic FGF to the osteoblast cultures from days 7 to 15 completely blocked nodule formation. Furthermore, addition of acidic FGF after nodule formation (days 14–29) inhibited matrix mineralization, which was associated with a marked increase in collagenase gene expression, and resulted in a progressive change in the morphology of the nodules, with only a few remnants of nonmineralized nodules present by day 29. Histochemical and biochemical analyses revealed a decrease in alkaline phosphatase and mineral content, confirming the acidic FGF-induced inhibition of nodule and matrix formation. To identify mechanisms contributing to these changes, we examined expression of cell growth and bone phenotypic markers. Addition of acidic FGF during the proliferative phase (days 7–8) enhanced histone H4, osteopontin, type 1 collagen, and TGF-β mRNA levels, which are coupled to proliferating osteoblasts, and blocked the normal developmental increase in alkaline phosphatase and osteocalcin gene expression and calcium accumulation. Addition of acidic FGF to the cultures during matrix maturation (days 14–15) reactivated H4, osteopontin, type I collagen, and TGF-β gene expression, and decreased alkaline phosphatase and osteocalcin gene expression. In an in vivo experiment, rats were treated with up to 60 μg/kg/day acidic FGF intravenously for 30 days. Proliferation of osteoblasts and deposition of bone occurred in the marrow space of the diaphysis of the femur in a dose-related fashion. The metaphyseal areas were unaffected by treatment. In conclusion, our data suggest that acidic FGF is a potent mitogen for early stage osteoblasts which leads to modifications in the formation of the extracellular matrix; increases in TGF-β and collagenase are functionally implicated in abrogating competency for nodule formation. Persistence of proliferation prevented expression of alkaline phosphatase and osteocalcin, also contributing to the block in the progression of the osteoblast developmental sequence. © 1996 Wiley-Liss, Inc. 相似文献
2.
A. Rattner O. Sabido C. Massoubre F. Rascle J. Frey 《In vitro cellular & developmental biology. Animal》1997,33(10):757-762
Summary Human osteoblastic cells were isolated enzymatically from adult human spongy bone and grown in MEM-Ham F12 1:1 medium supplemented
with 2% Ultroser (USM). They were subcultured and examined for osteoblast features by morphological, histological, and biochemical
approaches. The cells had a characteristic polyhedral morphology and produced a high level of alkaline phosphatase (ALKP).
Confluent cultures were uniformly stained for ALKP and flow cytometry analysis with fluorescein diphosphate gave a single
peak signal, reflecting a highly positive population, distinct from cultures of fibroblasts. The ALKP activity was stimulated
by 1,25 (OH)2 vitamin D3. CD 44 was strongly expressed in these cultures, although osteoblasts are negative in vivo and osteocytes are positive. The main collagen synthesized was type I collagen and osteocalcin was produced after stimulation
by vitamin D3. 10 mM βGP induced mineralization and microprobe analysis of the crystals showed a composition close to hydroxyapatite.
Changing the culture conditions to MEM-10% calf serum acted on cell behavior: it reduced the production of these biochemical
markers of osteoblasts and the morphology became fibroblastlike with more rapid cell multiplication. The parameter most affected
by the change in culture medium was ALKP, which was selected as the determinant criterion for defining an osteoblast culture.
ALKP activity was then used to characterize a culture of cells seeded in a collagen gel. 相似文献
3.
Elena I. Oprita Lucia Moldovan Oana Craciunescu Otilia Zarnescu 《Central European Journal of Biology》2008,3(1):31-37
The purpose of the present study was to investigate the effect of a collagen/β-tricalcium phosphate (COL/β-TCP) composite
on osteoblast growth and proliferation. The COL/β-TCP composite was prepared by mixing COL type I with β-TCP, in 1:1 (w/w)
ratio and conditioned as sponge by freeze-drying. The osteoblast culture was obtained from rat calvaria bones by enzymatic
digestion and cells were seeded in the COL/β-TCP composite. The cell morphology and viability, alkaline phosphatase and osteocalcin,
as markers of osteoblast proliferation were evaluated at 3, 7 and 25 days of culture. Histological sections revealed that
cell colonization progressively increased inside the COL/β-TCP scaffold, and osteoblasts had a random distribution throughout
the scaffold. Cells cultured into the COL/β-TCP scaffold presented osteoblast phenotype, intense staining of alkaline phosphatase
and increased production of osteocalcin. Transmission electron micrographs revealed intimate contacts between osteoblasts
and the scaffold. MTT test indicated that the viability of the cells cultivated in the presence of COL/β-TCP scaffold was
similar to that of the control. All these results show that our COL/β-TCP composite act as a good substrate for rat osteoblast
proliferation and migration and could be a promising substitute for bone repair. 相似文献
4.
Factors that promote progressive development of the osteoblast phenotype in cultured fetal rat calvaria cells 总被引:32,自引:0,他引:32
M A Aronow L C Gerstenfeld T A Owen M S Tassinari G S Stein J B Lian 《Journal of cellular physiology》1990,143(2):213-221
Rat calvaria osteoblasts derived from 21-day-old fetal rat pups undergo a temporal expression of markers of the osteoblast phenotype during a 5 week culture period. Alkaline phosphatase and osteocalcin are sequentially expressed in relation to collagen accumulation and mineralization. This pattern of expression of these osteoblast parameters in cultured rat osteoblasts (ROB) is analogous to that seen in vivo in developing fetal rat calvaria tissue (Yoon et. al: Biochem. Biophis. Res. Commun. 148:1129, 1987) and is similar to that observed in cultures of subcultivated 16-day-old embryonic chick calvaria-derived osteoblasts (COB) (Gerstenfeld, et.al: Dev. Biol. 122:46, 1987). While the cellular organization of subcultivated COB and primary ROB cultures are somewhat different, the temporal expression of the parameters remains. Both the rat and chick culture systems support formation of matrix mineralization even in the absence of beta-glycerol-phosphate. A systematic examination of factors which constitute conditions supporting complete expression of the osteoblast phenotype in ROB cultures indicate requirements for specific serum lots, ascorbic acid and the ordered deposition of mineral in the extracellular matrix. The present studies suggest that formation of a collagenous matrix, dependent on ascorbic acid, is requisite for expression of the osteoblast phenotype. In ROB cultures, expression of osteocalcin synthesis occurs subsequent to initiation of alkaline phosphatase activity and accompanies the formation of mineralized nodules. Thus, extracellular matrix mineralization (deposition of hydroxyapatite) is required for complete development of the osteoblast phenotype, as reflected by a 200-fold increase in osteocalcin synthesis. These data show the temporal expression of the various osteoblast parameters during the formation and mineralization of an extracellular matrix can provide markers reflective of various stages of osteoblast differentiation/maturation in vitro. 相似文献
5.
Seventeen day chicken embryonic osteoblasts treated over a 30-day period with 1,25(OH)2 D3 showed a 2–10-fold decrease in collagen, osteopontin and osteocalcin protein accumulation, alkaline phosphatase enzyme activity, and mineral deposition. Comparable inhibition in the steady state mRNA levels for α1(I) and α2(I) collagen, osteocalcin, and osteopontin were observed, and the inhibitory action of the hormone was shown to be specific for only the late release populations of cells from sequential enzyme digestions of the chick calvaria. In order to determine whether the continuous hormone treatment blocked osteoblast differentiation, the cells were acutely treated for 24 h with 1,25(OH)2 D3 at culture periods when the cells proliferate (day 5), a culture period when the cells cease further cell division and are increasing in the expression of their differentiated functions (day 17), and a culture period when the cells are encapsulated within a mineralized extracellular matrix (day 30). Inhibition of the expression of collagen, osteocalcin, and osteopontin were observed at days 17 and 30, while no effect could be detected for the 5-day cultures. To further define whether the inhibitory effect was specific for cells expressing their differentiated phenotype, 1,25(OH)2 D3 treatment was initiated at day 17 and continued to day 30 after the cells have established their collagenous matrix. In these experiments further collagenous matrix deposition, mineral deposition, alkaline phosphatase activity, and osteocalcin synthesis were also inhibited after the hormone treatment was initiated. These results, in summary, show that 1,25(OH)2 D3 in primary avian osteoblast cultures derived from 17-day embryonic calvaria inhibits the expression of several genes associated with differentiated osteoblast function and inhibit extracellular matrix mineral deposition. 相似文献
6.
7.
Carol V. Gay Qin P. Lloyd Virginia R. Gilman 《In vitro cellular & developmental biology. Animal》1994,30(6):379-383
Summary A method is presented for isolating primary osteoblasts from the periosteal surface of chick tibia. The culture system identified
supports both cell proliferation and phenotype retention. Cell numbers increased 8-fold in Week 1 and 20-fold over a total
of 12 days. Well-established osteoblast markers, alkaline phosphatase staining,γ-carboxyglutamic acid, osteocalcin, type I collagen, and parathyroid hormone binding were detected. Osteocalcin,γ-carboxyglutamic acid, and type I collagen were present on culture Day 4, and were increased in amount by Day 8, but were
similar to the earlier level on Day 12, suggesting that the phenotype may revert to a less differentiated state by 12 days
in culture. Alkaline phosphatase staining was intense at all three assay times, however. During the last 4 days of the 12-day
culture period, proliferation rates were higher than in the previous 8 days. 相似文献
8.
S. W. Hayward R. Dahiya G. R. Cunha J. Bartek N. Deshpande P. Narayan 《In vitro cellular & developmental biology. Animal》1995,31(1):14-24
Summary This report describes the development and characterization of an epithelial cell line (BPH-1) from human prostate tissue obtained
by transurethral resection. Primary epithelial cell cultures were immortalized with SV40 large T antigen. One of the isolated
clones was designated BPH-1. These cells have a cobblestone appearance in monolayer culture and are non-tumorigenic in nude
mice following subcutaneous injection or subrenal capsule grafting. They express the SV40 large T antigen and exhibit increased
levels of p53, as determined by immunocytochemistry. Cytogenetic analysis by G-banding demonstrated an aneuploid karyotype
with a modal chromosome number of 76 (range 71 to 79,n=28) and 6 to 8 marker chromosomes. Some structurally rearranged chromosomes were observed, but the Y chromosome was normal.
The expressed cytokeratin profile was consistent with a prostatic luminal epithelial cell. This profile was the same as that
of primary prostatic epithelial cultures from which the BPH-1 cells were derived. In serum-free culture in plastic dishes
epidermal growth factor (EGF), transforming growth factor (TGF)-α, fibroblast growth factor (FGF) 1 (aFGF), and FGF 7 (KGF) induced increased proliferation in these cells whereas FGF 2 (bFGF),
TGF-β1, and TGF-β2 inhibited proliferative activity. Testosterone had no direct effect on the proliferative rate of BPH-1 cells. 5α-Reductase, 3α-hydroxysteroid oxidoreductase, and 17β-hydroxy-steroid oxidoreductase activities were detected in BPH-1 cells. Expression of androgen receptors and the secretory
markers, prostate specific antigen and prostatic acid phosphatase, were not detectable by immunocytochemistry, biochemical
assay, or RT-PCR analysis. 相似文献
9.
The objective of this study was to examine the effect of two fibrinolytic inhibitors, aprotinin and aminohexanoic acid, on chondrogenesis of rabbit bone marrow mesenchymal stem cells (BM-MSCs). Rabbit BM-MSCs were obtained from the tibias and femurs of New Zealand White rabbits. Cell–fibrin constructs were made by mixing a cell–fibrinogen (107 cells/ml; 40 mg/ml fibrinogen) solution with a thrombin (5 IU/ml) solution and then divided into four groups: aprotinin control, aprotinin + transforming growth factor β (TGF-β), aminohexanoic acid control, and aminohexanoic acid + TGF-β. Each of these groups was further treated with three different concentrations of inhibitors and the TGF-β groups were treated with 10 ng/ml of TGF-β1. The chondrogenic gene expressions, DNA content, and glycosaminoglycan content of samples were analyzed after 14 days of culture. The aprotinin groups exhibited significantly higher levels of aggrecan gene expression and glycosaminoglycan content than the aminohexanoic acid groups. However, inhibitor neither influenced gene expression of type II collagen nor proliferation (i.e., DNA content) of BM-MSCs. These findings suggest that fibrinolytic inhibitors used to control degradation of fibrin clot may influence TGF-β-induced chondrogenesis of BM-MSCs. 相似文献
10.
Kaoru Hasegawa Ziqiu Wang Mitsuhiro Inagaki Brian I. Carr 《In vitro cellular & developmental biology. Animal》1995,31(1):55-61
Summary A new cell line (Hep 3B-TR), which is resistant to growth-inhibition by transforming growth factor beta 1 (TGF-β1) up to 10 ng/ml (400 pM), was isolated from parental Hep 3B human hepatoma cells, which are sensitive to growth-inhibition by TGF-β1. In the presence of TGF-β1 (1 to 10 ng/ml), the growth of the parental cell line (Hep 3B-TS) was inhibited by more than 95%. Under the same conditions,
the growth rate of the resistant clone (Hep 3B-TR) however, was identical in the presence or absence of TGF-β1 and was almost the same as that of the Hep 3B-TS cells in the absence of TGF-β1. Affinity crosslinking with 5 pM
125I-labeled TGF-β1 showed that the TGF-β1 receptors type I (TGF-βRI) and type II (TGF-βRII) were not present on the cell surface of the Hep 3B-TR cells, whereas they were present on the sensitive HEP 3B-TS cells.
Hep 3B-TS cells had detectable TGF-βRII mRNA, which was not found in Hep 3B-TR cells. RNA analysis showed different effects on the expression of TGF-β1, c-fos, c-myc, and protein disulfide isomerase (PDI) genes in the two cell lines in response to TGF-β1 protein. Addition of TGF-β1 (1 ng/ml) strongly increased the expression of TGF-β1 mRNA in Hep 3B-TS cells, but not in Hep 3B-TR cells. In Hep 3B-TS cells, c-fos mRNA was not detected either in the presence
or absence of TGF-β1 protein. However, abundant c-fos mRNA was detected in Hep 3B-TR cells, which was not altered by TGF-β1 protein. TGF-β1 protein inhibited the expression of c-myc and PDI mRNAs in Hep 3B-TS cells, whereas although the c-myc and PDI mRNAs were
much more abundant in Hep 3B-TR cells, their expression was not affected by TGF-β1 protein. These results suggest that the mechanisms of escape from growth-inhibition by TGF-β1 in Hep 3B-TR hepatoma cells probably involve loss of binding by TGF-β1 to its cell surface receptors. 相似文献
11.
Emily Hays Jaime Schmidt Nalini Chandar 《In vitro cellular & developmental biology. Animal》2009,45(7):361-370
Selective knockdown of phosphatase and tensin homolog (PTEN) has been recently shown to increase life long accumulation of
bone and its ability to increase osteoblast lifespan. In order to determine how loss of PTEN function affects osteoblast differentiation,
we created cell lines with stable knockdown of PTEN expression using short hairpin RNA vectors and characterized several clones.
The effect of deregulated PTEN in osteoblasts was studied in relationship to cell proliferation and differentiation. Downregulation
of PTEN initially affected the cell’s attachment and spreading on plastic but cells recovered after a brief period of time.
When cell proliferation was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, we noticed
a small but significant increase in growth rates with PTEN reduction. The size of individual cells appeared larger when compared
to control cells. Differentiation properties of these osteoblasts were increased as evidenced by higher expression of several
of the bone markers tested (alkaline phosphatase, osteocalcin, osterix, bone morphogenetic protein 2, Cbfa1, osteoprotegerin,
and receptor activator of NF-kappaB ligand) and their mineralization capacity in culture. As stabilization of beta-catenin
is known to be responsible for growth deregulation with PTEN loss in other cell types, we investigated the activation of the
canonical Wnt pathway in our cell lines. Immunofluorescence staining, protein expression in subcellular fractions for beta-catenin,
and assays for activation of the canonical Wnt/beta-catenin signaling were studied in the PTEN downregulated cells. There
was an overall decrease in β-catenin expression in cells with PTEN knockdown. The distribution of β-catenin was more diffuse
within the cell in the PTEN-reduced clones when compared to controls where they were mostly present in cell borders. Signaling
through the canonical pathway was also reduced in the PTEN knockdown cells when compared to control. The results of this study
suggest that while decreased PTEN augments cell proliferation and positively affects differentiation, there is a decrease
in β-catenin levels and activity in osteoblasts. Therefore, at least in osteoblasts, β-catenin is not responsible for mediating
the activation of osteoblast differentiation with reduction in PTEN function. 相似文献
12.
Relationship of cell growth to the regulation of tissue-specific gene expression during osteoblast differentiation 总被引:33,自引:0,他引:33
The relationship of cell proliferation to the temporal expression of genes characterizing a developmental sequence associated with bone cell differentiation can be examined in primary diploid cultures of fetal calvarial-derived osteoblasts by the combination of molecular, biochemical, histochemical, and ultrastructural approaches. Modifications in gene expression define a developmental sequence that has 1) three principal periods: proliferation, extracellular matrix maturation, and mineralization; and 2) two restriction points to which the cells can progress but cannot pass without further signals. The first restriction point is when proliferation is down-regulated and gene expression associated with extracellular matrix maturation is induced, and the second when mineralization occurs. Initially, actively proliferating cells, expressing cell cycle and cell growth regulated genes, produce a fibronectin/type I collagen extracellular matrix. A reciprocal and functionally coupled relationship between the decline in proliferative activity and the subsequent induction of genes associated with matrix maturation and mineralization is supported by 1) a temporal sequence of events in which an enhanced expression of alkaline phosphatase occurs immediately after the proliferative period, and later an increased expression of osteocalcin and osteopontin at the onset of mineralization; 2) increased expression of a specific subset of osteoblast phenotype markers, alkaline phosphatase and osteopontin, when proliferation is inhibited; and 3) enhanced levels of expression of the osteoblast markers when collagen deposition is promoted, suggesting that the extracellular matrix contributes to both the shutdown of proliferation and development of the osteoblast phenotype. The loss of stringent growth control in transformed osteoblasts and in osteosarcoma cells is accompanied by a deregulation of the tightly coupled relationship between proliferation and progressive expression of genes associated with bone cell differentiation. 相似文献
13.
Osteoblasts isolated from mouse calvaria initiate matrix mineralization in culture 总被引:20,自引:5,他引:15
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《The Journal of cell biology》1983,96(3):639-643
A method is presented for isolating osteoblasts from newborn mouse calvaria without the use of digestive enzymes. The procedure is based on the ability of osteoblasts to migrate from bone onto small glass fragments (Jones, S.J., and A. Boyde, 1977, Cell Tissue Res., 184:179- 193). The isolated cells were cultured for up to 14 d in Dulbecco's modified Eagle's medium supplemented with 10% fetal calf serum and 50 micrograms/ml of ascorbic acid. 7-d cultures were incubated for 24 h with [3H]proline. High levels of collagen synthesis relative to total protein were found, as measured by collagenase digestion of medium and cell layer proteins. Analysis of pepsin-digested proteins from the same cultures by SDS PAGE showed that type I collagen was predominantly produced with small amounts of type III and V (alpha 1 chains) collagens. Osteoblasts grown in the presence of beta-glycerophosphate were able to initiate mineral deposition in culture. Electron microscopic analysis of the cultures revealed the presence of needle- shaped apatite-like crystals associated with collagen fibrils and vesicles in the extracellular space. Mouse skin fibroblasts cultured under identical conditions failed to initiate mineralization. Electron histochemical studies revealed the presence of alkaline phosphatase activity, associated with osteoblast membranes, matrix vesicles and on or near collagen fibrils. Thus these isolated osteoblasts retained in culture their unique property of initiating mineralization and therefore represent a model of value for studying the mineralization process in vitro. 相似文献
14.
Lennart Franzén Claes Dahlquist 《In vitro cellular & developmental biology. Animal》1994,30(7):460-463
Summary Transforming growth factor-β (TGF-β) has varying effects on cell proliferation, stimulating some cell types while inhibiting others. Its effect on proliferation
has mostly been assessed in cell cultures without consideration for the influence of a tissue matrix. In the present investigation
we studied the effect of TGF-β on fibroblast cell proliferation in intact connective tissue in vitro using the membranous part of the rat mesentery. Mesenteric
membranes were spread over the hole of a cytocentrifuge paper, incubated in vitro, and exposed to various concentrations of
TGF-β with or without serum added. At designated times after incubation, the specimens were fixed, spread out on microscope slides,
and stained by the Feulgen reaction. Cell proliferation was estimated by counting mitoses in fibroblasts and mesothelial cells
and by DNA cytometry of fibroblast nuclei using computer assisted image analyses. Higher concentrations of TGF-β significantly increased proliferation estimated as either the percentage of cells in the S+G2 phase of the cell cycle or the mitotic index when serum was added. In medium without serum, TGF-β did slightly, but not significantly, increase proliferation. The results show that TGF-β stimulates connective tissue cell proliferation dose-dependently in intact connective tissue in vitro and that addition of
serum to the medium is a prerequisite for optimal stimulation. 相似文献
15.
Insulin‐like growth factor‐1 promotes osteogenic differentiation and collagen I alpha 2 synthesis via induction of mRNA‐binding protein LARP6 expression
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Yue Guo Chen‐Yi Tang Xiao‐Fei Man Hao‐Neng Tang Jun Tang Ci‐La Zhou Shu‐Wen Tan Min Wang Yun‐Zhi Feng Hou‐De Zhou 《Development, growth & differentiation》2017,59(2):94-103
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18.
《Phytomedicine》2014,21(12):1498-1503
Phytoestrogen-rich Pueraria mirifica (PM) tuberous extract is a promising candidate for the development of anti-osteoporosis drugs for postmenopausal women, but its action has never been validated in humans or in non-human primates, which are more closely related to humans than rodents. In vitro study of non-human primate osteoblasts is thus fundamental to prepare for in vivo studies of phytoestrogen effects on primate bone. This study aimed to establish a culture system of baboon primary osteoblasts and to investigate the effects of PM extract and its phytoestrogens on these cells. Primary osteoblasts from adult baboon fibulae exhibited osteoblast characteristics in regard to proliferation, differentiation, mineralization, and estrogen receptor expression. They responded to 17β-estradiol by increased proliferation rate and mRNA levels of alkaline phosphatase (ALP), type I collagen, and osteocalcin. After being exposed for 48 h to 100 μg/ml PM extract, 1000 nM genistein, or 1000 nM puerarin, primary baboon osteoblasts markedly increased the rate of proliferation and mRNA levels of ALP and type I collagen without changes in Runx2, osterix, or osteocalcin expression. PM extract, genistein, and puerarin also decreased the RANKL/OPG ratio, suggesting that they could decrease osteoclast-mediated bone resorption. However, neither PM extract nor its phytoestrogens altered calcium deposition in osteoblast culture. In conclusion, we have established baboon primary osteoblast culture, which is a new tool for bone research and drug discovery. Furthermore, the present results provide substantial support for the potential of PM extract and its phytoestrogens to be developed as therapeutic agents against bone fragility. 相似文献
19.
Recombinant expression of human transforming growth factor-β isoforms in Chinese hamster ovary cells
Transforming growth factor-βs (TGF-βs) are multi functional growth modulators implicated in several physiological processes which include embryogenesis, inflammation,
immune-suppression, wound healing, carcinogenesis and cellular differentiation. For clinical use, recombinant expression of
TGF-βs is the only practical source because of very low yields from natural sources. Here, we report the recombinant expression
of human TGF-βl and TGF-β2 in a mammalian expression system using a high expression eukaryotic vector driven by a cytomegalovirus promoter. Expression
levels are as high as 0.97 μg/ml of TGF-βl and 0.24 μg/ml of TGF-β2 in conditioned media, sufficient for purification without the need for amplification of the gene using methotrexate. 相似文献
20.
Joelle Vilamitjana-Amedee Reine Bareille Francois Rouais Arnold I. Caplan Marie-Francoise Harmand 《In vitro cellular & developmental biology. Animal》1993,29(9):699-707
Summary This study reports the selection and characterization of osteogenic precursors from human bone marrow which were isolated
by two “clonings” and successive subculturing. These cell lines express alkaline phosphatase activity. Gel electrophoresis
of [3H]-proline labeled cultures showed that the cloned cells produce only type I collagen. They synthetize osteocalcin and osteonectin.
They respond to 1,25 dihydroxy vitamin D3 by increasing osteocalcin synthesis and secretion, and to parathyroid hormone by increasing cyclic AMP synthesis. After the
third subculture in the absence of β-glycerophosphate, these cell lines formed lots of clusters which exhibit high alkaline
phosphatase activity and positive von Kossa staining. X-ray energy spectrum shows that these cells are surrounded by “budding”
structures containing calcium and phosphorus with a ratio Ca:P identical to those of pure hydroxyapatite. This process was
associated with45Ca uptake into the cells. All these data support the selection of osteogenic cells which may be of considerable clinical importance. 相似文献