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Tang XK, Cheng W, Xu B, Ying H, Tong PJ, Xiao LW. [Experimental study on the isolated culture of osteocytes and identification of osteoblasts in rats]. ZHONGGUO GU SHANG = CHINA JOURNAL OF ORTHOPAEDICS AND TRAUMATOLOGY 2013; 26:227-231. [PMID: 23795443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
OBJECTIVE To establish a more stable method to isolate osteocytes in vitro, and then to find the differences with osteoblast biological characteristics. METHODS Osteocytes and osteoblasts were isolated from the bone tissue of 3-day-old rats using sequential collagenase digestion. The cells were identified through cell morphology after 24 hours later. Alkaline phosphatase (ALP) kit was used to stain the first generation cells by Kaplow-way, the bone gla protein (BGP) of the cells were stained by immunocytochemitry. Measured ALP and computed its activity. RESULTS Osteocytes and osteoblasts showed obviously differences in cell morphology. Osteocytes were star-shaped or dendrite-shaped within more dendrites, while osteoblasts were spindle-shaped with short dendrites. Osteocytes were negative for ALP, but osteoblasts were positive; Osteocytes were more positive for BGP, and osteoblasts were less positive. The secretion of ALP in osteocytes was lower than that of osteoblasts. CONCLUSION Osteocytes can be isolated and cultured in vitro. These characteristics of osteocytes are apparently difference with those of osteoblasts.
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Tübel J, Saldamli B, Wiest I, Jeschke U, Burgkart R. Expression of the tumor markers sialyl Lewis A, sialyl Lewis X, Lewis Y, Thomsen-Friedenreich antigen, galectin-1 and galectin-3 in human osteoblasts in vitro. Anticancer Res 2012; 32:2159-2164. [PMID: 22593503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
AIM Lewis antigens and the Thomsen-Friedenreich (TF) antigen are complex glycan structures that modulate processes such as cell adhesion and proliferation and tumor metastasis. The aim of our study was to analyze the expression of sialyl Lewis A (sLeA), sialyl Lewis X (sLeX), Lewis Y (LeY), TF, galectin-1 (Gal-1) and galectin-3 (Gal-3) in human osteoblasts in vitro. MATERIALS AND METHODS The expression of the tumor markers sLeA, sLeX, LeY, TF, Gal-1 and Gal-3 was studied by means of immunohistochemistry on cells grown on chamber slides (2D) and on paraffin sections three-dimensional scaffold-free cultures (3D). The results of the stainings were evaluated semiquantitatively with the immunoreactive scoring system (IRS). RESULTS Analysis of sLeA expression in both types of culture, 2D and 3D showed no detectable staining. After 5 days, in the 2D culture, expression of sLeX was weak, but the 3D culture (after 56 weeks) displayed a strong expression. LeY was expressed very slightly in the 2D culture, however LeY was not detectable in the 3D culture. The TF epitope was identified in the 2D cell culture model. In the 3D model, however, TF was completely lacking. Gal-1 was expressed very strongly in 2D culture, but in the 3D culture was not detectable. In contrast, Gal-3 was expressed in 3D culture but not in 2D. CONCLUSION Within this study, we present a systematic analysis of the expression of sLeA, sLeX, LeY, TF, Gal-1 and Gal-3 in human osteoblasts grown in 2D and in 3D scaffold-free cultures. Summarizing the results of our study, we suggest that Lewis antigens and Gal-1 and -3 might play an important role in cell-cell and cell-matrix interactions of osteoblastic cells.
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Ishikawa M, Kondo H, Onuma M, Shibuya H, Sato T. Osteoblastic osteosarcoma in a rabbit. Comp Med 2012; 62:124-126. [PMID: 22546918 PMCID: PMC3318249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Revised: 10/01/2011] [Accepted: 11/02/2011] [Indexed: 05/31/2023]
Abstract
An osteosarcoma developed in the tarsal joint region involving the distal tibia of a domestic rabbit (Oryctolagus cuniculus). Micrometastases were present in the lungs. Histologically the tumor was composed of ovoid to short-spindle cells with abundant giant cells, producing irregular islands of osteoids. The tumor cells were immunopositive with antiosteocalcin monoclonal antibody, consistent with their derivation from osteoblasts. According to review of 10 published cases, productive osteoblasic osteosarcoma is the most common bone tumor in rabbits, with half of all cases developing in the skull or facial bones.
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Schiano C, Grimaldi V, Casamassimi A, Infante T, Esposito A, Giovane A, Napoli C. Different expression of CD146 in human normal and osteosarcoma cell lines. Med Oncol 2012; 29:2998-3002. [PMID: 22271434 DOI: 10.1007/s12032-012-0158-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 01/04/2012] [Indexed: 01/15/2023]
Abstract
The CD146 cell membrane adhesion molecule is highly expressed on the cell surface of several tumours. The level of its expression has been found to correlate directly with tumour progression and metastatic potential, thus establishing CD146 as an important candidate of tumour growth and metastasis. In order to characterize its expression in human osteosarcoma (OS) cell lines, we have examined the CD146 expression at protein and RNA levels in both normal and tumour osteoblast-like cell lines by several methods. Our results indicate that CD146 protein is expressed at low levels in normal osteoblast cells whereas it is highly expressed in all OS cell lines analysed, (SaOS, MG-63, U-2OS). Moreover, CD146 overexpression was partially reduced in shYY1 cells, where the Yin Yang 1 transcription factor, also found over-expressed in human OS cells, has been silenced.
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Abstract
This chapter describes the isolation, culture and staining of primary osteoblasts from the calvaria and long bones of neonatal rats. The key advantages of this assay are that it allows direct measurement of bone matrix deposition and mineralisation, as well as yielding good quantities of osteoblasts at defined stages of differentiation for molecular and histological analysis. A special focus of this chapter is on the role of β-glycerophosphate in cell-mediated mineralisation in these cultures.
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Liu X, Deng C, Liu J, Li J, Sui G. [Research on the extracorporeal cytocompatibility of a composite of HA, carbon fiber and polyetheretherket-one]. SHENG WU YI XUE GONG CHENG XUE ZA ZHI = JOURNAL OF BIOMEDICAL ENGINEERING = SHENGWU YIXUE GONGCHENGXUE ZAZHI 2011; 28:1159-1164. [PMID: 22295706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The present research was to study the biocompatibility of a composite of hydroxyapatite (HA), carbon fiber (CF) and polyetheretherket-one (PEEK) by co-culturing with the osteoblasts in vitro. Cell relative growth (RGR) was used as a quantitative assessment for cytotoxicity of the biomaterials by CCK-8. The proliferation index of the co-cultured cells and ALP activity was measured to study the effect of PEEK-HA-CF composites. Morphological properties of the osteoblast cells in vitro were observed by scanning electro-microscopy (SEM). The PEEK-HA-CF materials have no cytotoxicity to osteoblasts. The proliferation index of PEEK-HA-CF was higher than that of Ti alloy group, but these was no significant difference compared to that of control group. The ALP activity was the highest on PEEK-HA-CF composites surface after 7 days. The osteoblast cells co-cultured with the PEEK-HA-CF composite were adhered well to the biomaterial as observed under the SEM. The results suggested that the PEEK-HA-CF composites had good biocompatibility in vitro and might be a novel orthopedic implanted material.
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Gongadze E, Van Rienen U, Iglič A. Generalized stern models of the electric double layer considering the spatial variation of permittvity and finite size of ions in saturation regime. Cell Mol Biol Lett 2011; 16:576-94. [PMID: 21847663 PMCID: PMC6275889 DOI: 10.2478/s11658-011-0024-x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Accepted: 08/12/2011] [Indexed: 11/20/2022] Open
Abstract
The interaction between a charged metal implant surface and a surrounding body fluid (electrolyte solution) leads to ion redistribution and thus to formation of an electrical double layer (EDL). The physical properties of the EDL contribute essentially to the formation of the complex implant-biosystem interface. Study of the EDL began in 1879 by Hermann von Helmholtz and still today remains a scientific challenge. The present mini review is focused on introducing the generalized Stern theory of an EDL, which takes into account the orientational ordering of water molecules. To ascertain the plausibility of the generalized Stern models described, we follow the classical model of Stern and introduce two Langevin models for spatial variation of the relative permittivity for point-like and finite sized ions. We attempt to uncover the subtle interplay between water ordering and finite sized ions and their impact on the electric potential near the charged implant surface. Two complementary effects appear to account for the spatial dependency of the relative permittivity near the charged implant surface - the dipole moment vectors of water molecules are predominantly oriented towards the surface and water molecules are depleted due to the accumulation of counterions. At the end the expressions for relative permittivity in both Langevin models were generalized by also taking into account the cavity and reaction field.
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Chen J, Zheng Y, Tan Q, Shojaei-Baghini E, Zhang YL, Li J, Prasad P, You L, Wu XY, Sun Y. Classification of cell types using a microfluidic device for mechanical and electrical measurement on single cells. LAB ON A CHIP 2011; 11:3174-81. [PMID: 21826361 DOI: 10.1039/c1lc20473d] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
This paper presents a microfluidic system for cell type classification using mechanical and electrical measurements on single cells. Cells are aspirated continuously through a constriction channel with cell elongations and impedance profiles measured simultaneously. The cell transit time through the constriction channel and the impedance amplitude ratio are quantified as cell's mechanical and electrical property indicators. The microfluidic device and measurement system were used to characterize osteoblasts (n=206) and osteocytes (n=217), revealing that osteoblasts, compared with osteocytes, have a larger cell elongation length (64.51 ± 14.98 μm vs. 39.78 ± 7.16 μm), a longer transit time (1.84 ± 1.48 s vs. 0.94 ± 1.07 s), and a higher impedance amplitude ratio (1.198 ± 0.071 vs. 1.099 ± 0.038). Pattern recognition using the neural network was applied to cell type classification, resulting in classification success rates of 69.8% (transit time alone), 85.3% (impedance amplitude ratio alone), and 93.7% (both transit time and impedance amplitude ratio as input to neural network) for osteoblasts and osteocytes. The system was also applied to test EMT6 (n=747) and EMT6/AR1.0 cells (n=770, EMT6 treated by doxorubicin) that have a comparable size distribution (cell elongation length: 51.47 ± 11.33 μm vs. 50.09 ± 9.70 μm). The effects of cell size on transit time and impedance amplitude ratio were investigated. Cell classification success rates were 51.3% (cell elongation alone), 57.5% (transit time alone), 59.6% (impedance amplitude ratio alone), and 70.2% (both transit time and impedance amplitude ratio). These preliminary results suggest that biomechanical and bioelectrical parameters, when used in combination, could provide a higher cell classification success rate than using electrical or mechanical parameter alone.
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Hristova K, Pecheva E, Pramatarova L, Altankov G. Improved interaction of osteoblast-like cells with apatite-nanodiamond coatings depends on fibronectin. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2011; 22:1891-1900. [PMID: 21706219 DOI: 10.1007/s10856-011-4357-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Accepted: 05/23/2011] [Indexed: 05/31/2023]
Abstract
New apatite (AP)/nanodiamond (ND) coating has been developed to improve physical and biological properties of stainless steel (SS) versus single AP coating. Homogeneously electrodeposited AP-ND layer demonstrates increased mechanical strength, interlayer cohesion and ductility. In the absence of serum, osteoblast-like MG63 cells attach well but poorly spread on both AP and AP-ND substrata. Pre-adsorption with serum or fibronectin (FN) improves the cellular interaction-an effect that is better pronounced on the AP-ND coating. In single protein adsorption study fluorescein isothiocyanate-labeled FN (FITC-FN) shows enhanced deposition on the AP-ND layer consistent with the significantly improved cell adhesion, spreading and focal adhesions formation (in comparison to SS and AP), particularly at low FN adsorption concentrations (1 μg/ml). Higher FN concentrations (20 μg/ml) abolish this difference suggesting that the promoted cellular interaction of serum (where FN is low) is caused by the greater affinity for FN. Moreover, it is found that MG63 cells tend to rearrange both adsorbed and secreted FN on the AP-ND layer suggesting facilitated FN matrix formation.
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Zhou H, Touny AH, Bhaduri SB. Fabrication of novel PLA/CDHA bionanocomposite fibers for tissue engineering applications via electrospinning. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2011; 22:1183-1193. [PMID: 21431905 DOI: 10.1007/s10856-011-4295-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Accepted: 03/14/2011] [Indexed: 05/30/2023]
Abstract
The main theme here is to fabricate PLA (poly lactic-acid)/CDHA (carbonated calcium deficient hydroxyapatite) bionanocomposites, where both the constituents are biocompatible and biodegradable with one dimension in nanometer scale. Such materials are important in tissue engineering applications. The bionanocomposite fibers were fabricated via electrospinning. There are two important signatures of this paper. First, CDHA, rather than HA, is added to PLA as the second phase. As opposed to HA, CDHA mimics the bone mineral composition better and is biodegradable. Therefore, PLA/CDHA fibers should have better biodegradability while maintaining a physiological pH during degradation. To the best of our knowledge, this is the first attempt of electrospinning of such a composite. Second, the CDHA nanoparticles were synthesized using the benign low temperature biomimetic technique, the only route available for the retention of carbonate ions in the HA lattice. The structural properties, degradation behavior, bioactivity, cell adhesion, and growth capability of as-fabricated PLA/CDHA bionanocomposites were investigated. The results show that the incorporation of CDHA decreased PLA fiber diameters, accelerated PLA degradation, buffered pH decrease caused by PLA degradation, improved the bioactivity and biocompatibility of the scaffold. These results prove that PLA/CDHA bionanocomposites have the potential in tissue regeneration applications.
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Lim YW, Kwon SY, Sun DH, Kim YS. The Otto Aufranc Award: enhanced biocompatibility of stainless steel implants by titanium coating and microarc oxidation. Clin Orthop Relat Res 2011; 469:330-8. [PMID: 20936386 PMCID: PMC3018231 DOI: 10.1007/s11999-010-1613-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Stainless steel is one of the most widely used biomaterials for internal fixation devices, but is not used in cementless arthroplasty implants because a stable oxide layer essential for biocompatibility cannot be formed on the surface. We applied a Ti electron beam coating, to form oxide layer on the stainless steel surface. To form a thicker oxide layer, we used a microarc oxidation process on the surface of Ti coated stainless steel. Modification of the surface using Ti electron beam coating and microarc oxidation could improve the ability of stainless steel implants to osseointegrate. QUESTIONS/PURPOSES The ability of cells to adhere to grit-blasted, titanium-coated, microarc-oxidated stainless steel in vitro was compared with that of two different types of surface modifications, machined and titanium-coated, and microarc-oxidated. METHODS We performed energy-dispersive x-ray spectroscopy and scanning electron microscopy investigations to assess the chemical composition and structure of the stainless steel surfaces and cell morphology. The biologic responses of an osteoblastlike cell line (SaOS-2) were examined by measuring proliferation (cell proliferation assay), differentiation (alkaline phosphatase activity), and attraction ability (cell migration assay). RESULTS Cell proliferation, alkaline phosphatase activity, migration, and adhesion were increased in the grit-blasted, titanium-coated, microarc-oxidated group compared to the two other groups. Osteoblastlike cells on the grit-blasted, titanium-coated, microarc-oxidated surface were strongly adhered, and proliferated well compared to those on the other surfaces. CONCLUSIONS The surface modifications we used (grit blasting, titanium coating, microarc oxidation) enhanced the biocompatibility (proliferation and migration of osteoblastlike cells) of stainless steel. CLINICAL RELEVANCE This process is not unique to stainless steel; it can be applied to many metals to improve their biocompatibility, thus allowing a broad range of materials to be used for cementless implants.
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Gaharwar AK, Schexnailder PJ, Jin Q, Wu CJ, Schmidt G. Addition of chitosan to silicate cross-linked PEO for tuning osteoblast cell adhesion and mineralization. ACS APPLIED MATERIALS & INTERFACES 2010; 2:3119-3127. [PMID: 20949937 DOI: 10.1021/am100609t] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The addition of chitosan to silicate (Laponite) cross-linked poly(ethylene oxide) (PEO) is used for tuning nanocomposite material properties and tailoring cellular adhesion and bioactivity. By combining the characteristics of chitosan (which promotes cell adhesion and growth, antimicrobial) with properties of PEO (prevents protein and cell adhesion) and those of Laponite (bioactive), the resulting material properties can be used to tune cellular adhesion and control biomineralization. Here, we present the hydration, dissolution, degradation, and mechanical properties of multiphase bio-nanocomposites and relate these to the cell growth of MC3T3-E1 mouse preosteoblast cells. We find that the structural integrity of these bio-nanocomposites is improved by the addition of chitosan, but the release of entrapped proteins is suppressed. Overall, this study shows how chitosan can be used to tune properties in Laponite cross-linked PEO for creating bioactive scaffolds to be considered for bone repair.
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Byun IS, Sarkar SK, Anirban Jyoti M, Min YK, Seo HS, Lee BT, Song HY. Initial biocompatibility and enhanced osteoblast response of Si doping in a porous BCP bone graft substitute. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2010; 21:1937-1947. [PMID: 20361241 DOI: 10.1007/s10856-010-4061-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Accepted: 03/15/2010] [Indexed: 05/29/2023]
Abstract
Granular shape biphasic calcium phosphate (BCP) bone grafts with and without doping of silicon cations were evaluated in regards to biocompatibility and MG-63 cellular response. To do this we studied Cellular cytotoxicity, cellular adhesion and spreading behavior and cellular differentiation with alizarin red S staining. Gene expression in MG-63 cells on the implanted bone substitutes was also examined at different time points using RT-PCR. In comparison, the Si-doped BCP granule showed more cellular viability than the BCP granule without doping in MTT assay. Moreover, cell proliferation was much higher when Si doping was employed. The cells grown on the silicon-doped BCP substitutes had more active filopodial growth with cytoplasmic webbing that proceeded to the flattening stage, which was indicative of well cellular adhesion. When these cells were exposed to Si-doped BCP granules for 14 days, well differentiated MG-63 cells were observed. Osteonectin and osteopontin genes were highly expressed in the late stage of differentiation (14 days), whereas collagen type I mRNA were found to be highly expressed during the early stage (day 3). These combined results of this study demonstrate that silicon-doped BCP enhanced osteoblast attachment/spreading, proliferation, differentiation and gene expression.
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Dai M, Yuan X, Fan H, Cheng M, Ai J. [Expression of receptor activator of nuclear factor kappaB ligand and osteoprotegerin of mice osteoblast induced by metal ions]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 2010; 24:292-295. [PMID: 20369527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
OBJECTIVE Lots of metal ions accumulation and over-expression of receptor activator of NF-kappaB ligand (RANKL) around the prosthesis could be found in revision of total hip arthroplasty. To investigate the relationship between metal ions and aseptic loosening by observing the effects of Co2+ and Cr3+ ions on the expression of RANKL and osteoprotegerin (OPG) from osteoblast. METHODS Osteoblasts were cultured in vitro at the density of 1 x 10(5) cells/mL, and were divided into 2 groups according to different culture solutions. In control group, osteoblasts were cultured with normal medium without CoCl2 and CrCl3. In experimental group, osteoblasts were cultured with the medium including CoCl2 (10 mg/L) and CrCl3 (150 mg/L) solutions. The RT-PCR and ELISA methods were applied to detect the mRNA expression of RANKL and OPG and protein level at 24 and 48 hours after co-cultured, respectively. RESULTS RT-PCR revealed that the mRNA expression of RANKL and OPG could be found in two groups at 24 and 48 hours after co-cultured, the expression was higher in the experimental group than in control group, especially the expression of RANKL, showing significant difference (P < 0.05). At 24 and 48 hours after co-cultured, the ratios of RANKL mRNA to OPG mRNA in the experimental group were 0.860 and 1.232, respectively, which were significantly higher than those in the control group (0.695 and 0.688, P < 0.05). ELISA revealed that the protein level of RANKL and OPG in experimental group were significantly higher than those in the control group (P < 0.05). CONCLUSION Co2+ and Cr3+ can stimulate the mRNA expressions of RANKL, OPG and secretion of those protein from osteoblasts, especially increase of the RANKL, which promotes the formation and activation of osteoblasts and the generation of aseptic loosening.
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Kwan T, Grundberg E, Koka V, Ge B, Lam KCL, Dias C, Kindmark A, Mallmin H, Ljunggren O, Rivadeneira F, Estrada K, van Meurs JB, Uitterlinden A, Karlsson M, Ohlsson C, Mellström D, Nilsson O, Pastinen T, Majewski J. Tissue effect on genetic control of transcript isoform variation. PLoS Genet 2009; 5:e1000608. [PMID: 19680542 PMCID: PMC2719916 DOI: 10.1371/journal.pgen.1000608] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2009] [Accepted: 07/20/2009] [Indexed: 11/26/2022] Open
Abstract
Current genome-wide association studies (GWAS) are moving towards the use of large cohorts of primary cell lines to study a disease of interest and to assign biological relevance to the genetic signals identified. Here, we use a panel of human osteoblasts (HObs) to carry out a transcriptomic survey, similar to recent studies in lymphoblastoid cell lines (LCLs). The distinct nature of HObs and LCLs is reflected by the preferential grouping of cell type–specific genes within biologically and functionally relevant pathways unique to each tissue type. We performed cis-association analysis with SNP genotypes to identify genetic variations of transcript isoforms, and our analysis indicates that differential expression of transcript isoforms in HObs is also partly controlled by cis-regulatory genetic variants. These isoforms are regulated by genetic variants in both a tissue-specific and tissue-independent fashion, and these associations have been confirmed by RT–PCR validation. Our study suggests that multiple transcript isoforms are often present in both tissues and that genetic control may affect the relative expression of one isoform to another, rather than having an all-or-none effect. Examination of the top SNPs from a GWAS of bone mineral density show overlap with probeset associations observed in this study. The top hit corresponding to the FAM118A gene was tested for association studies in two additional clinical studies, revealing a novel transcript isoform variant. Our approach to examining transcriptome variation in multiple tissue types is useful for detecting the proportion of genetic variation common to different cell types and for the identification of cell-specific isoform variants that may be functionally relevant, an important follow-up step for GWAS. The transcriptome of any given cell type is a complex program of controlled gene expression underlying its biological function. An additional layer of molecular complexity involving individual genetic variation can modulate the transcriptome within the same tissue type, conferring potential phenotypic differences between individuals at the cellular level. This study highlights common and unique aspects of the transcriptome between the well-characterized lymphoblastoid cell lines from the International HapMap Project and those of a cultured primary cell type, human osteoblasts. We observe that inter-individual genetic variation can regulate transcript isoform expression in tissue-specific and tissue-independent manners, indicating that genetic differences among individuals can alter the transcriptome in one or more tissues, ultimately leading to altered biological functions within the lymphoblasts and/or osteoblasts. Pursuant to this, genome wide association studies on bone mineral density (BMD) have identified a number of significant loci and polymorphisms highly linked to the BMD quantitative phenotype. A small proportion of these polymorphisms overlap with our highly significant SNPs regulating the osteoblast transcriptome, revealing a potential molecular basis for this phenotype at the transcriptional level. This study highlights the importance of examining the differing transcriptomes and cis-regulatory mechanisms governing the biological and functional roles of varied tissue types.
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Egli RJ, Wingenfeld C, Hölzle M, Hempfing A, Fraitzl CR, Ganz R, Leunig M. Histopathology of Cryopreserved Bone Allo- and Isografts: Pretreatment with Dimethyl Sulfoxide. J INVEST SURG 2009; 19:87-96. [PMID: 16531366 DOI: 10.1080/08941930600569050] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Partial graft cell survival and enhanced graft revascularization have suggested fast freezing using the cryoprotective substance dimethyl sulfoxide (DMSO) as a promising means to improve the biologic function and immune tolerance of allograft bone. This study determines the presence of osteoblasts (cola(1)(I) mRNA), osteoclasts (TRAP), and cytotoxic T cells (CTLs; GrA mRNA) within pretreated bone grafts 12 days after transplantation. The grafts were transplanted either as isografts, allografts, or allografts in presensitized recipients. In fresh isografts, serving as control, well-formed blood vessels and the highest numbers of viable osteoblasts and osteoclasts were found. In fresh allografts, blood vessels were observed within the marrow cavity and the bone was partially covered by osteoblasts and osteoclasts accompanied by CTLs. In DMSO-pretreated frozen allografts, blood vessels together with osteoblasts were observed in three of five, but in none of five grafts frozen without DMSO. However, infiltration with CTLs was higher in DMSO-pretreated frozen allografts when compared to grafts frozen without DMSO. In presensitized allograft recipients, independent of the pretreatment, in none of the grafts were either blood vessels or osteoblasts found. Thus, fast cryopreservation of bone using DMSO improves vascularization and expression of cola(1)(I) mRNA (osteoblasts) after allografting when compared to cryopreservation alone, potentially improving graft incorporation. As these grafts were still invaded by CTLs, the long-term effect of DMSO pretreatment needs to be defined.
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Speth RC. Serotonin rising. N Engl J Med 2009; 360:2581; author reply 2581-2. [PMID: 19533828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
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Tsai WB, Ting YC, Yang JY, Lai JY, Liu HL. Fibronectin modulates the morphology of osteoblast-like cells (MG-63) on nano-grooved substrates. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2009; 20:1367-1378. [PMID: 19132502 DOI: 10.1007/s10856-008-3687-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2008] [Accepted: 12/29/2008] [Indexed: 05/27/2023]
Abstract
Cell interactions with biomaterials are affected by surface topographic and chemical cues. Although it is well-known that nanometrical grooves/ridges structure modulates cellular spreading, elongation, and alignment, the combinational influence of surface topographic and chemical cues is not well studied. In this study, nano-textured silicon substrata with parallel ridges of 90, 250, or 500 nm wide, separated by grooves with equal width, were fabricated by electron beam lithography and dry etching techniques. Osteoblast-like cells, MG-63, were cultured on the patterned substrata with or without pre-adsorption of fibronectin. The cell morphology was imaged by scanning electron microscopy, and analyzed by image software. We found that FN coating initially modulated cellular spreading, length, and orientation on all types of grooved surfaces. However, after 24 h of culture, the cell morphology was not affected by FN coating on the 250-nm and 500-nm surfaces, while FN decreased cell alignment on the 90-nm surfaces. Our results suggest that surface chemical cues influence the initial cell-substratum contact, while the long-term cellular morphology is dictated by surface topographic cues.
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Yu Y, Ren H, Yun W, Jin Y, Li K, Du L. [Differentiation of human umbilical cord blood-derived mesenchymal stem cells into chondroblast and osteoblasts]. SHENG WU YI XUE GONG CHENG XUE ZA ZHI = JOURNAL OF BIOMEDICAL ENGINEERING = SHENGWU YIXUE GONGCHENGXUE ZAZHI 2008; 25:1385-1389. [PMID: 19166215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Samples of healthy and full-term human umbilical cord blood samples were obtained asceptically. Mesenchymal stem cells (MSCs) were isolated by lymphocyte separation medium, and were characterized morphologically by fluorescence-activated cell sorting analysis. Differentiation of chondroblast and osteoblast was induced by 10 ng/ml TGF-beta, 100 ng/ml insulin and 10(-7) mol/L decaesadril, 6.25 microg/ml siderophilin, 10 mmol/L beta-sodium glycerophosphate, 50 microg/ml antiscorbic acid, respectirely; the aim was to investigate the potentiality of differentiation. Umbilical cord blood-derived MSCs were stained positive for MSCs marker CD13, CD90, CD166, CD73, CD44 and HLA-AB, but were negative for hematopoietic stem cell marker CD45, CD34 and HLA-DR. After 21 days induction, Toluidine Blue staining and von-Kossa staining were positive. Immunocytochemistry showed that Collagen II expressed in the induced cells. The results demonstrated that mesenchymal stem cells can be isolated from human umbilical cord blood and differentiated into chondroblasts and osteoblasts in vitro.
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Kaji H, Naito J, Inoue Y, Sowa H, Sugimoto T, Chihara K. Statin suppresses apoptosis in osteoblastic cells: role of transforming growth factor-beta-Smad3 pathway. Horm Metab Res 2008; 40:746-51. [PMID: 18622892 DOI: 10.1055/s-0028-1082051] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Statins possess pleiotropic effects in several tissues. Among them, their bone anabolic actions have been recently noted. We have proposed that Smad3, a TGF-beta-signaling molecule, is a promoter of bone formation. However, whether statins would affect TGF-beta-Smad3 pathway in osteoblasts is still unknown. The present study was performed to examine the effects of statin on Smad3 expression and cell apoptosis by employing mouse osteoblastic MC3T3-E1 and rat osteoblastic UMR-106 cells. Statins (pitavastatin, mevastatin, and simvastatin) as well as alendronate increased the levels of Smad3 in MC3T3-E1 cells. The effects of pitavastatin on Smad3 levels were observed from 3 hours and later. Pitavastatin induced the expression of TGF-beta, and cycloheximide, a protein synthesis inhibitor, antagonized the increased levels of pitavastatin on Smad3. On the other hand, pitavastatin antagonized dexamethasone- or etoposide-induced apoptosis in a dose-dependent manner, and Smad3 inactivation by dominant negative Smad3 or an inhibition of endogenous TGF-beta action by SB431542 antagonized anti-apoptotic effects of pitavastatin, indicating that pitavastatin suppressed osteoblast apoptosis partly through TGF-beta-Smad3 pathway. In conclusion, the present study has demonstrated for the first time that statin suppressed cell apoptosis partly through TGF-beta-Smad3 pathway in osteoblastic cells.
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Isales CM, Hamrick M. Nutritional hormones and the entero-osseous axis. JOURNAL OF MUSCULOSKELETAL & NEURONAL INTERACTIONS 2008; 8:348-350. [PMID: 19147971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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Salie R, Li H, Jiang X, Rowe DW, Kalajzic I, Susa M. A rapid, nonradioactive in situ hybridization technique for use on cryosectioned adult mouse bone. Calcif Tissue Int 2008; 83:212-21. [PMID: 18762852 DOI: 10.1007/s00223-008-9154-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2007] [Accepted: 06/03/2008] [Indexed: 10/21/2022]
Abstract
In situ hybridization (ISH) of adult bone is a difficult task that requires at least 3-5 weeks for decalcification, paraffin embedding, and sectioning. For that reason, bone ISH is often done only on embryonic or newborn animal tissue, leaving unanswered the question of gene expression in adults. Here, we report the development of an ISH system that requires only 7 days for acid-free decalcification, embedding, and sectioning, conditions that are conducive to preservation of tissue mRNA. The tissue cryosections, derived from adult mice 3-12 weeks old, were cut using the CryoJane Tape Transfer system. Paraffin-sectioned and cryosectioned tissue have comparable morphology. Examples are given of cryosections that were hybridized and stained enzymatically with digoxigenin-labeled riboprobes for mRNA found in either bone-forming osteoblasts (type I collagen, osteocalcin, Runx2) or the hypertrophic or proliferating chondrocytes (type X collagen, Runx2).
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Fan J, Li H, Jiang J, So LKY, Lam YW, Chu PK. 3C-SiC nanocrystals as fluorescent biological labels. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2008; 4:1058-62. [PMID: 18618492 DOI: 10.1002/smll.200800080] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
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Heino TJ, Chagin AS, Sävendahl L. The novel estrogen receptor G-protein-coupled receptor 30 is expressed in human bone. J Endocrinol 2008; 197:R1-6. [PMID: 18434348 DOI: 10.1677/joe-07-0629] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Estrogens have significant impact on bone mineral metabolism. Besides the classical estrogen receptors (ERalpha and ERbeta), a trans-membrane G-protein-coupled receptor (GPR30) has been demonstrated to mediate estrogenic effects. We aimed to study whether GPR30 is expressed in bone cells and if so, whether the level of expression is developmentally regulated. Metaphyseal bone biopsies were collected from the tibia in 14 boys and 6 girls, all at different stages of puberty. GPR30 protein expression was studied by immunohistochemistry in paraffin-embedded sections. GPR30-positive osteocytes and osteoblasts were quantified and linear regression analysis was applied. Cytoplasmic GPR30 expression was detected in osteoblasts, osteocytes, and osteoclasts. Osteocytes were more frequently positive for GPR30 than osteoblasts (58+/-4% vs 46+/-3% positive cells respectively, P<0.05). Detailed analysis demonstrated that GPR30 positivity declined during pubertal development in osteocytes (R=-0.56, P<0.01) but not in osteoblasts (R=-0.31, P>0.05). No sex difference was observed in the numbers of GPR30-positive osteoblasts or osteocytes. Furthermore, GPR30 expression did not correlate with chronological or bone age. In conclusion, the novel ER GPR30 is expressed in osteoblasts, osteocytes, and osteoclasts suggesting that non-genomic estrogen signaling via GPR30 may exist in bone. However, the functional role of GPR30 in bone tissue remains to be elucidated.
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Ho YC, Huang FM, Chang YC. Cytotoxicity of formaldehyde on human osteoblastic cells is related to intracellular glutathione levels. J Biomed Mater Res B Appl Biomater 2007; 83:340-4. [PMID: 17385229 DOI: 10.1002/jbm.b.30801] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Formaldehyde that leaches out of formaldehyde-releasing root canal sealers, specifically from setting material extruded into the periapical region may participate in the development of periapical inflammation or the continuation of a pre-existing periapical lesion. However, the effects of formaldehyde on human osteoblasts have not been investigated. The aim of this study was to evaluate the mechanisms of cytotoxicity of formaldehyde on human osteoblastic cell line U2OS in vitro. Cytotoxicity and cell proliferation assays were performed to elucidate the adverse effects of formaldehyde on U2OS cells. Formaldehyde demonstrated a cytotoxic effect to U2OS cells in a dose-dependent manner (p<0.05). The 50% inhibition concentration of formaldehyde was about 3 mM. Formaldehyde also inhibited cell proliferation during a 3-day culture period (p<0.05). To determine whether glutathione (GSH) levels were important in the cytotoxicity of formaldehyde, we pretreated cells with the GSH precursor, 2-oxothiazolidine-4-carboxylic acid (OTZ) to boost thiol levels, or buthionine sulfoximine (BSO) to deplete GSH. The addition of OTZ acted as a protective effect on the formaldehyde-induced cytotoxicity (p<0.05). In contrast, the addition of BSO enhanced the formaldehyde-induced cytotoxicity (p<0.05). Taken together, the levels of formaldehyde tested inhibited cell growth and proliferation on U2OS cells. Formaldehyde has significant potential for periapical toxicity. These inhibitory effects were associated with intracellular GSH levels.
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