scholarly journals Isolation of bone cell clones with differences in growth, hormone responses, and extracellular matrix production.

1982 ◽  
Vol 92 (2) ◽  
pp. 452-461 ◽  
Author(s):  
J E Aubin ◽  
J N Heersche ◽  
M J Merrilees ◽  
J Sodek

Clones of nontransformed hormone-responsive bone cells have been isolated in vitro from mixed cell populations of fetal rat calvaria. In several independent isolations, microscopically visible colonies appeared at plating efficiencies of 5-10% of the starting cell numbers. Of these clones, approximately 10% grew to mass populations which could be assayed for a number of growth and biochemical properties. Although some similarities existed among the clones, they could be distinguished from each other and from the mixed cell populations. Population-doubling times (tDs) and saturation densities varied over a wide range: e.g., tDs of 24-72 h and saturation densities of 0.4-5 x 10(5) cells/cm2. Morphologies varied from roughly polygonal multilayering cells to typically spindle-shaped monolayering cells. Hormone responsiveness, as measured by stimulation of cAMP by hormones, indicated that some clones were responsive to both parathyroid hormone (PTH) and prostaglandin E2 (PGE2), while others responded to PTH only. Analysis of extracellular matrix components revealed that all clones produced type I and type III collagens, though in different proportions. Similarly, although all clones synthesized four glycosaminoglycans (hyaluronic acid, heparan sulfate, chondroitin sulfate, and dermatan sulfate), the quantities of each were distinctive from clone to clone. Further investigation of such clones is continuing to define more precisely the heterogeneity of clonal bone cell populations in vitro. They represent an important step in the study of the endocrinology and differentiation of bone.

2014 ◽  
Vol 783-786 ◽  
pp. 72-77 ◽  
Author(s):  
Takayoshi Nakano ◽  
Aira Matsugaki ◽  
Takuya Ishimoto ◽  
Mitsuharu Todai ◽  
Ai Serizawa ◽  
...  

Bone microstructure is dominantly composed of anisotropic extracellular matrix (ECM) in which collagen fibers and epitaxially-oriented biological apatite (BAp) crystals are preferentially aligned depending on the bone anatomical position, resulting in exerting appropriate mechanical function. The regenerative bone in bony defects is however produced without the preferential alignment of collagen fibers and the c-axis of BAp crystals, and subsequently reproduced to recover toward intact alignment. Thus, it is necessary to produce the anisotropic bone-mimetic tissue for the quick recovery of original bone tissue and the related mechanical ability in the early stage of bone regeneration. Our group is focusing on the methodology for regulating the arrangement of bone cells, the following secretion of collagen and the self-assembled mineralization by oriented BAp crystallites. Cyclic stretching in vitro to bone cells, principal-stress loading in vivo on scaffolds, step formation by slip traces on Ti single crystal, surface modification by laser induced periodic surface structure (LIPSS), anisotropic collagen substrate with the different degree of orientation, etc. can dominate bone cell arrangement and lead to the construction of the oriented ECM similar to the bone tissue architecture. This suggests that stress/strain loading, surface topography and chemical anisotropy are useful to produce bone-like microstructure in order to promote the regeneration of anisotropic bone tissue and to understand the controlling parameters for anisotropic osteogenesis induction.


2020 ◽  
Author(s):  
Shinji Iizuka ◽  
Ronald P. Leon ◽  
Kyle P. Gribbin ◽  
Ying Zhang ◽  
Jose Navarro ◽  
...  

ABSTRACTThe scaffold protein Tks5α is required for invadopodia-mediated cancer invasion both in vitro and in vivo. We have previously also revealed a role for Tks5 in tumor cell growth using three-dimensional (3D) culture model systems and mouse transplantation experiments. Here we use both 3D and high-density fibrillar collagen (HDFC) culture to demonstrate that native type I collagen, but not a form lacking the telopeptides, stimulated Tks5-dependent growth, which was dependent on the DDR collagen receptors. We used microenvironmental microarray (MEMA) technology to determine that laminin, collagen I, fibronectin and tropoelastin also stimulated invadopodia formation. A Tks5α-specific monoclonal antibody revealed its expression both on microtubules and at invadopodia. High- and super-resolution microscopy of cells in and on collagen was then used to place Tks5α at the base of invadopodia, separated from much of the actin and cortactin, but coincident with both matrix metalloprotease and cathepsin proteolytic activity. Inhibition of the Src family kinases, cathepsins or metalloproteases all reduced invadopodia length but each had distinct effects on Tks5α localization. These studies highlight the crosstalk between invadopodia and extracellular matrix components, and reveal the invadopodium to be a spatially complex structure.


1987 ◽  
Vol 248 (1) ◽  
pp. 129-137 ◽  
Author(s):  
G Adamek ◽  
R Felix ◽  
H L Guenther ◽  
H Fleisch

Fatty acid oxidation and its hormonal modulation were investigated in cultured rat calvaria and in cultivated cell populations. The latter were obtained from calvaria of newborn rats by sequential time-dependent digestion with collagenase, yielding eight cell populations: the early ones containing mainly fibroblasts, the middle ones being osteoblast-like, and late ones osteoblast-osteocyte-like. In calvaria, fatty acid oxidation was increased by adding 0.1 mM- and 1.0 mM-palmitate to the medium, containing 10% (v/v) fetal-calf serum. No effect was found after parathyrin addition in vitro or when injected in vivo. All cell populations obtained by sequential digestion were found to oxidize palmitate, whereby the osteoblast-like cells showed a lower oxidation rate than the other populations. Both parathyrin and calcitonin had no effect on fatty acid oxidation. 1,25-Dihydroxycholecalciferol at 1-100 nM and 24,25-dihydroxycholecalciferol at 100 nM increased oxidation primarily in the population enriched with osteoblast-like cells. Insulin at 1.6 microM diminished it in the cell populations enriched with osteoblast-like cells and in the late bone-cell fraction. However, glucagon had no effect. The energy provided by fatty acid oxidation in this system is approx. 40-80% of glucose metabolism, suggesting that this event may be of importance in the energy metabolism of bone.


1991 ◽  
Vol 39 (11) ◽  
pp. 1539-1546 ◽  
Author(s):  
J Lannes-Vieira ◽  
M Dardenne ◽  
W Savino

The present investigation was an ontogenetic study on the distribution of extracellular matrix (ECM) components in the thymic microenvironment of C57BL/6 mice (comprising young and old adults and developing embryos) and NZB mice. In addition, we evaluated the in vivo and in vitro influence of hydrocortisone treatment on basement membrane protein production by a thymic epithelial cell line. In young normal animals, Type I collagen was restricted to the interstitial spaces of the capsule and septa, where Type IV collagen, fibronectin, and laminin could be detected in the basement membranes. In addition, fibronectin-containing fibers were seen within the medulla of the thymic lobules. The ECM distribution pattern in the developing embryos was distinct from that observed in adults, since a fine meshwork of basement membrane-containing proteins was clearly seen throughout the parenchyma. Moreover, aging normal and NZB mice exhibited a denser ECM pattern than young adult normal animals. Treatment with hydrocortisone, both in vivo and in vitro, resulted in enhancement of ECM expression, detected in mice as early as 2 hr post injection and lasting for several days. Considering that the fluctuations of ECM expression parallel important events in thymocyte differentiation, we discuss the possibility that the two phenomena may be associated.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Wei Dai ◽  
Shenglan Liu ◽  
Shubo Wang ◽  
Li Zhao ◽  
Xiao Yang ◽  
...  

AbstractColonization is believed a rate-limiting step of metastasis cascade. However, its underlying mechanism is not well understood. Uveal melanoma (UM), which is featured with single organ liver metastasis, may provide a simplified model for realizing the complicated colonization process. Because DDR1 was identified to be overexpressed in UM cell lines and specimens, and abundant pathological deposition of extracellular matrix collagen, a type of DDR1 ligand, was noted in the microenvironment of liver in metastatic patients with UM, we postulated the hypothesis that DDR1 and its ligand might ignite the interaction between UM cells and their surrounding niche of liver thereby conferring strengthened survival, proliferation, stemness and eventually promoting metastatic colonization in liver. We tested this hypothesis and found that DDR1 promoted these malignant cellular phenotypes and facilitated metastatic colonization of UM in liver. Mechanistically, UM cells secreted TGF-β1 which induced quiescent hepatic stellate cells (qHSCs) into activated HSCs (aHSCs) which secreted collagen type I. Such a remodeling of extracellular matrix, in turn, activated DDR1, strengthening survival through upregulating STAT3-dependent Mcl-1 expression, enhancing stemness via upregulating STAT3-dependent SOX2, and promoting clonogenicity in cancer cells. Targeting DDR1 by using 7rh, a specific inhibitor, repressed proliferation and survival in vitro and in vivo outgrowth. More importantly, targeting cancer cells by pharmacological inactivation of DDR1 or targeting microenvironmental TGF-β1-collagen I loop exhibited a prominent anti-metastasis effect in mice. In conclusion, targeting DDR1 signaling and TGF-β signaling may be a novel approach to diminish hepatic metastasis in UM.


1988 ◽  
Vol 91 (2) ◽  
pp. 281-286
Author(s):  
M.C. Copeman ◽  
H. Harris

It has been shown that when malignant tumour cells are fused with normal fibroblasts the suppression of malignancy in the hybrids is linked to their ability to produce a collagenous extracellular matrix in vivo. When, as a consequence of chromosome loss, segregants arise that reacquire malignancy, these do not produce any detectable matrix. In this paper we examine the main components of the extracellular matrix produced in vitro by hybrids between malignant mouse melanoma cells and normal mouse fibroblasts. Hybrids in which malignancy is suppressed synthesize about ten times as much type 1 procollagen as the malignant segregants derived from them; they also retain more fibronectin in the cell layer and release less protease activity into the medium. Malignant segregants more closely resemble the parental melanoma cells in producing fibronectin and mainly types IV and V procollagen. When hybrid cells in which malignancy is initially suppressed are grown continuously in vitro, the production of type I procollagen declines, and the production of type V procollagen and the release of protease activity into the medium increase. These changes, which are associated with the loss from the hybrid cells of both copies of the chromosome 4 derived from the parental fibroblast, predict the reacquisition of malignancy when the cells are inoculated into mice. It is possible that one gene or set of genes located on chromosome 4 determines both the execution of the fibroblast differentiation programme and the suppression of malignancy.


Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Karien J Rodriguez ◽  
Kristyn S Masters

Calcification is the leading cause of bioprosthetic and native aortic valve failure, but relatively little is known regarding the factors that contribute to the progression of valvular calcification. Because extracellular matrix (ECM) disarray is often observed in explanted diseased valves, we have investigated the role of individual ECM components in the in vitro calcification of valvular interstitial cells (VICs). The transformation of VICs to an osteoblast-like phenotype was quantified in VICs cultured on different types of ECM coatings. The results show that the number and size of calcific nodules formed in VIC cultures, as well as the expression of mineralization markers alkaline phosphatase (ALP) and CBFa1, were highly dependent upon the composition of the culture surface. In fact, VICs cultured on certain ECM components, namely collagen (Coll) and fibronectin (FN), were resistant to calcification, even upon treatment with potent mineralization-inducing growth factors, such as transforming growth factor beta1 (TGFb1). Meanwhile, VIC cultures on fibrin (FB), laminin, and heparin not only had a high number of calcified nodules (p<0.001 vs. Coll, FN), but also elevated levels of ALP and CBFa1 (p<0.02), and the number of nodules on these ‘pro-calcific’ coatings significantly increased upon treatment with exogenous TGFb1 (p<0.05). To explain the ECM-dependence of calcification, the endogenous production of a pro-mineralization factor (TGFb1) was assessed in VICs on anti-calcific (Coll) and pro-calcific (FB) substrates. Quantification of TGFb1 mRNA revealed that VICs on Coll surfaces expressed a significantly lower amount of TGFb1 mRNA than VICs on FB (p<0.01). Furthermore, treatment with a neutralizing antibody to TGFb1 decreased TGFb1 mRNA expression by VICs on Coll in comparison to VICs on FB or polystyrene controls (p<0.02). Thus, we have discovered a strong correlation between VIC calcification and ECM composition. Our findings show that the ECM plays an important role in controlling TGFb1 expression and subsequent calcification of VICs, which may significantly impact the design of biomaterials for valve tissue engineering, understanding of valvular disease, and the development of preventative treatments for valve calcification.


1994 ◽  
Vol 130 (4) ◽  
pp. 381-386 ◽  
Author(s):  
Moustapha Kassem ◽  
Leif Mosekilde ◽  
Erik F Eriksen

Kassem M, Mosekilde L, Eriksen EF. Effects of fluoride on human bone cells in vitro: differences in responsiveness between stromal osteoblast precursors and mature osteoblasts. Eur J Endocrinol 1994;130:381–6. ISSN 0804–4643 The cellular effects of sodium fluoride (NaF) on human bone cells in vitro have been variable and dependent on the culture system used. Variability could be attributed to differences in responsiveness to NaF among different populations of cells at various stages of differentiation in the osteoblastic lineage. In this study we compared the effects of NaF in serum-free medium on cultures of more differentiated human osteoblast-like (hOB) cells derived from trabecular bone explants and on osteoblast committed precursors derived from human bone marrow, i.e. human marrow stromal osteoblast-like (hMS(OB)) cells. Sodium fluoride (10−5 mol/l) increased proliferation of hMS(OB) cells (p<0.05, N = 10) but was not mitogenic to hOB cells (p>0.05, N= 10). Alkaline phosphatase (AP) production increased in both hMS(OB) (p<0.05, N=9) and hOB cells (p<0.05, N=9). No significant effects on procollagen type I propeptide production were obtained in either culture. In the presence of 1,25-dihydroxycholecalciferol (10−9 mol/l), NaF enhanced alkaline phosphatase (p<0.05, N=8), procollagen type I propeptide (p<0.05, N=7) and osteocalcin (p<0.05, N=7) production by hMS(OB) cells but not by hOB cells. Our results suggest that osteoblast precursors are more sensitive to NaF action than mature osteoblasts and that the in vivo effects of NaF on bone formation may be mediated by stimulating proliferation and differentiation of committed osteoblast precursors in bone marrow. M Kassem, Mayo Clinic, Endocrine Research Unit, W-Joseph 5-164, Rochester, MN 55904, USA


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