Expression of IL-1α, IL-6, TGF-β, FasL and ZNF265 During Sertoli Cell Infection by Ureaplasma Urealyticum

To investigate immunoregulatory mechanisms of Sertoli cells in the testis in vitro and in vivo, we utilized our well-characterized Ureaplasma Urealyticum （UU）-induced model. We investigated the expressions of IL-1α, IL-6, TGF-β, FasL and ZNF265 at the first, second and third weeks post-infection. During recovery from inflammation and with the help of negative regulators TGF-β and FasL, the high levels of IL-1α and IL-6 expressions were observed in the early stages of the infection, and decreased gradually in the later weeks both in vitro and in vivo. The trend of varied expression of ZNF265 was similar to those of TGF-β and FasL in vitro and in vivo for Sertoli cells infected with UU.     

Application of Stem Cells in Tissue Engineering

Stem cells have become an important source of seed cells for tissue engineering because they are relatively easy to expand in vitro and can be induced to differentiate into various cell types in vitro or in vivo. In the current stage, most stem cell researches focus on in vitro studies, including in vitro induction and phenotype characterization. Our center has made a great deal of effort in the in vivo study by using stem cells as seed cells for tissue construction. We have used bone marrow s…     

Dysfunction of murine dendritic cells induced by incubation with tumor cells

In vivo studies showed that dendritic cell （DC） dysfunction occurred in tumor microenvironment. As tumors were composed of many kinds of cells, the direct effects of tumor cells on immature DCs （imDCs） are needed for further studies in vitro. In the present study, bone marrow-derived imDCs were incubated with lymphoma, hepatoma and menaloma cells in vitro and surface molecules in imDCs were determined by flow cytometry. Then, imDCs incubated with tumor cells or control imDCs were further pulsed with tumor lysates and then incubated with splenocytes to perform mixed lymphocyte reaction. The DC-dependent tumor antigen-specific T cell proliferation, and IL-12 secretion were determined by flow cytometry, and enzyme-linked immunosorbent assay respectively. Finally, the DC-dependent tumor-associated antigen-specific CTL was determined by enzyme-linked immunospot assay. The results showed that tumor cell-DC incubation down-regulated the surface molecules in imDCs, such as CD80, CD54, CDIIb, CDIIa and MHC class II molecules. The abilities of DC-dependent antigen-specific T cell proliferation and IL-12 secretion were also decreased by tumor cell incubation in vitro. Most importantly, the ability for antigenic-specific CTL priming of DCs was also decreased by incubation with tumor cells. In the present in vitro study demonstrated that the defective abilities of DCs induced by tumor cell co-incubation and the co-incubation system might be useful for future study of tumor-immune cells direct interaction and for drug screen of immune-modulation. Cellular ＆ Molecular Immunology.     

Sox2 enhances the tumorigenicity and chemoresistance of cancer stem-like cells derived from gastric cancer

Gastric cancer stem-like cells(GCSCs) have been identified to possess the ability of self-renewal and tumor initi-ation.However,the mechanisms involved remain largely unknown.Here,we isolated and characterized the GCSCs by side population(SP) sorting procedure and cultured sphere cells(SC) from human gastric cancer cell lines SGC-7901,BGC-823,MGC-803,HGC-27 and MKN-28.The sorting and culture assay revealed that SP cells proliferated in an asymmetric division manner.In addition,SP cells exhibited a higher potential of spheroid colony formation and greater drug resistance than non-SP cells(NSP).Moreover,the SC were found with enhanced capabilities of drug resistance in vitro and tumorigenicity in vivo.Sox2 mRNA and protein was highly and significantly overex-pressed in the SP cells and SC.Importantly,downregulation of Sox2 with siRNA obviously reduced spheroid colony formation and doxorubicin efflux,as well as increased apoptosis rate in sphere cells in vitro and suppressed tumori-genicity in vivo.These results suggest that both SP cells and cultured SC enrich with GCSCs and that Sox2 plays a pivotal role in sustaining stem cell properties and might be a potential target for gastric cancer therapy.     

Studies on the Specific Degranulation of Mast Cell Sensitized by Several Allergens in vitro

Food allergy is a major health issue worldwide. Mast cells play a very important role in the immediate hypersensitivity for which mast cell degranulation needs to be studied extensively. In this study, an approach was taken to study the characteristics of sensitized mast cell degranulation in vitro, which associated with the study of mast cells and animal models. BALB/c mice were immunized respectively by several food allergens, then blood and peritoneal mast cells were collected at different time points. A dynamic determination was carried out between mast cells and serumal IgE. Comparative analysis on sequential time points showed that there was a close coincidence between mast cell degranulation and IgE antibody titers in sensitized BALB/c mice. Furthermore, it is interesting that sensitized mast cells could implement specific degranulation against the challenges in vitro, but the closely tropomyosins induced mast cell degranulation displayed cross reactions. This is very similar to IgE resisting the allergens in vivo. The study disclosed some characteristics on mast cells, coming from sensitized BALB/c mice, degranulation in vitro.     

Relaxin promotes differentiation of human breast cancer cells MCF-7 transplanted into nude mice

Previous studies showed that the hormone relaxin acts on human breast cancer MCF-7 cells in vitro by modulating cell proliferation and promoting cell differentiation toward a duct epithelial phenotype. The present study was designed to investigate whether relaxin retains these properties when acting in vivo on MCF-7 cell tumors developed in athymic nude mice. Mice bearing MCF-7 cell tumors transplanted under the mammary fat pad and estrogenized to sustain tumor growth were treated systemically with relaxin (10 μg/day) for 19 days. Vehicle-treated mice were used as controls. Thirty days later, the mice were sacrificed and tumor fragments were analyzed by light and electron microscopy and immunocytochemistry. Measurements of tumor volume were recorded weekly for the overall experimental period. The results obtained indicate that relaxin treatment promotes differentiation of tumor cells towards both myoepithelial-like and epithelial-like cells, as judged by the ultrastructural features of the cells and by the increased expression of smooth muscle actin and cadherins. Measurements of tumor size and of the number of cycling cells show that relaxin, at the doses and times of exposure used in this study, does not significantly influence tumor growth and cell proliferation. Received: 3 March 1999 / Accepted: 28 May 1999     

UVA1 irradiation inhibits fibroblast proliferation and alleviates pathological changes of scleroderma in a mouse model

The purpose of the present study was to compare the effects of different doses of ultraviolet radiation A1 (UVA1) on human fibroblast proliferation and collagen level in a mouse model of scleroderma,so as to identify appropriate irradiation doses for clinical treatment of scleroderma.Monolayer from human fibroblasts was cultured in vitro,and a mouse model of scleroderma was established by subcutaneous injection of 100 μL of 400 μg/mL bleomycin into the back of BALB/c mice for 4 weeks.The mouse models and human fibroblasts were divided into UVA1exposed (100,60 and 20 J/cm 2) and UVA-unexposed groups.At 0,24 and 48 h after exposure,cell proliferation and levels of hydroxyproline and collagen were detected.UVA1 irradiation was performed 3 times weekly for 10 weeks,and the pathological changes of skin tissues,skin thickness and collagen level were observed after phototherapy.Cell proliferation and the levels of hydroxyproline and collagen were inhibited after phototherapy,and there was a significant difference between the UVA1-exposed cells and UVA1-unexposed cells (P < 0.001).In addition,UVA1 phototherapy improved dermal sclerosis and softened the skin,and there were significant differences between the high-dose UVA1 group and the model group,and the negative group (P < 0.05).It is concluded that UVA1 radiation can reduce cell proliferation,and decrease hydroxyproline and collagen levels in a dose-dependent manner in vitro.High-dose UVA1 phototherapy has marked therapeutic effect on scleroderma in the mouse model.Decreased collagen level may be related to the reduced number and activity of cells,as well as inhibition of collagen synthesis.     

Antiviral effect of polysaccharide from Spirulina platensis （ PSP ） on HSV-2 in vitro

To explore the antiviral effect and mechanism of polysaccharide from Spirulina platensis (PSP) on herpes simplex vims type 2 (HSV-2), a standard strain of HSV-2 (333 strain) was used to investigate the antiviral effect of PSP in vitro . PSP in various concentrations was applied to different stages of HSV-2 replication cycle. Finally, the virus infectivity (TCID50),cytopathic effect (CPE), and MTT staining method for viable cells (MTT assay) were used as markers to evaluate the effect of PSP on HSV-2. The quantity of HSV-DNA was detected by real-time fluorescence quantitative PCR (FQ-PCR). The HSV-2 infected Vero cell ultrastructures were observed by transmission electron microscopy (TEM). The results showed that PSP had little cytotoxic effect on Vero cells, it could not directly inactivate HSV-2 infectivity. PSP not only interfered in adsorption of HSV-2 to Vero cells but also inllibited HSV-2 biosynthesis in the cells. FQ-PCR results showed that the inhibitory rate on HSV-DNA also increased in a dose-dependent and time-dependent manner. TEM also confirmed that PSP exhibited pronounced inhibitory effect on HSV-2. In conclusion, the antiviral effect of PSP on HSV-2 may be attributed to the inhibition of vims adsorption, vims replication and synthesis in cells.     

The precursor frequency of alloreactive CTLs is proportional to the number of T cell epitope specificities

The aim of this study is to find the experimental evidence that the precursor frequency of alloreactive CTLs is proportional to the number of the T-cell epitope specificities. The number of T-cell epitope specificities was manipulated by pulsing different number of HLA-A2 restricted peptide(s) onto the T2 cells, which acted as stimulating cells to elicit allo-reaction by co-culturing with peripheral blood lymphocytes (PBLs) of HLA-A2 negative individual. Ten HLA-A2 restricted peptides (all were normal cell components) were synthesized, and cell peptide extract was prepared by frozen and thawed.T2 cells loaded with different number of peptide(s) were co-cultured with PBLs of an HLA-A2 negative individual; the latter were stained with PKH67 in advance. Then the proliferation was monitored with flow cytometry, and the precursor frequency of the effector cells was analyzed by the ModFit Software. After 6 d of culture, no proliferation was observed in the bulk culture of PBL alone, and obvious proliferation took place when PBLs of the HLA-A2 negative were co-cultured with T2 cells loaded with or without loading peptide(s). The precursor frequency of the alloreactive CTLs was 0.052 819 for co-culture with T2 cells loaded without peptide; however it was 0.030 429 for T2 cells with EBV/ LMP2A and 0. 030 528 for T2 cells loaded with a single autogeneic peptide, and increased up to 0.144 942 for T2 cells loaded with 10 autogeneic peptides; the precursor frequency was 0.203 649 when co-cultured with T2 cells loaded with miscellaneous peptides extracted from the cytoplasm of T2 cells. This study reveals that the precursor frequency of alloreactive CTLs is proportional to the number of T-cell epitope specificities, and independent of the density of the allogeneic HLA ClassⅠmolecule. Our findings support the hypothesis that the alloreactive T cell populations comprise miscellaneous T cell clones; each is specific to corresponding pMHC. The novel constellation of peptides presented by allogeneic MHC molecules makes thousands of different epitopes, which account for the exceptional high precursor frequency of alloreactive T cells.     

差速贴壁法原代培养椎间盘髓核细胞中的应用优势

BACKGROUND: As the main function cell of intervertebral disc, nucleus pulposus cells are the focus of studying the degenerative mechanism; thereby, it is crucial to maintaining the physiological function of nucleus pulposus cells in vitro and the stability of the cell phenotype. OBJECTIVE: To study the excellence of differential velocity adherent procedure in primary culture of nucleus pulposus cells of rat intervertebral disc through comparison. METHODS: Twenty male Wistar rats aged 4 weeks were enrolled, and then nucleus pulposus cells of intervertebral disc were isolated and cultured in vitro; cell passage culture was performed in different groups when the primary cells were merged to 90%. Differential velocity adherent group cells adhered for 30 minutes, and non-adherent cells were aspirated and transferred to new culture dish after readjusting the concentration; the controls received no intervention. Passages 1 and 2 cells in the differential velocity adherent group were isolated and purified by the same procedure. The morphology of three generations of cells in the two groups was compared, the purity of the identification was detected by immunohistochemistry, the cell viability was detected by cell counting kit-8 and the cell growth curve was drawn. RESULTS AND CONCLUSION: Inverted phase contrast microscope and hematoxylin-eosin staining revealed that the cell homogeneity of the differential velocity adherent group was significantly higher than that of the control group, and there were more kinds of fibroblast-like cells in nucleus pulposus cells in the control group. Identification and purity analysis of collagen type II showed that the cytoplasm of two groups were both stained brown, indicating that they were the nucleus pulposus chrondrocytes. The positive rate of differential velocity adherent group was significantly higher than that of the control group (P < 0.05). The cell growth curve of cell counting kit-8 showed cells in the two groups all passed by the latency phase within 2 days, then to the logarithmic phase of 3 days, and entered the lag phase, while the growth rate of the control group was more rapid during the latency and the early logarithmic phases. These findings suggest that differential velocity adherence method is a practical and effective procedure for the isolation and purification of primary cultured rat nucleus pulposus cells. Through the primary culture, twice differential velocity adherence procedure, the passage 3 rat nucleus pulposus cells are metabolic exuberant, consistent with the phenotype, the cell purity is higher, and the logarithmic growth phase can be used as the optimal time for studying the mechanism of intervertebral disc cells. 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

Large-scale Vero cell culture on microcarriers in a twenty-liter stirred tank fermentor

In biotechnology, animal cell culture is an important process for the production of many biologicals such as vaccines, monoclonal antibodies, or other recombinant products. Among many established continuous cell lines, Vero cells can be maintained in many passages in cultures without inducing tumorigenicity and have been recommended by World Health Organization for the production of human biologicals. Owing to its anchorage-dependent growth characteristics, Vero cells can be grown on microcarrier in a suspension vessel where microcarrier provides the culture system with a high culture surface to volume ratio. In this paper we compared the growth kinetics of Vero cells on Cytodex 1 microcarrier in a 20-liter fermentor vs. 100 ml spinner flask culture. The kinetics of Vero cell growth in the 20-liter fermentor was similar to the results obtained from small spinner flask culture, as determined by cell specific growth rate or corresponding doubling time. The approximately 150-fold increase in culture vessel volume did not compromise the growth kinetics of Vero cells, suggesting the system is applicable for large stirred-tank fermentor cultures.     

Mosquito cells bind and replicate hepatitis C virus

Several studies have demonstrated some hepatitis C virus (HCV) replication in lymphocyte and hepatocyte cell lines such as in African green monkey Vero cells. The aim of the present study was to select other cell lines able to bind and replicate HCV. Human hepatoma PLC/PRF/5 cells, human lymphoma Namalwa cells, Vero and mosquito AP61 cells were inoculated with HCV-positive plasma, washed six times and examined for the presence of the viral genome at different times post infection, using an RT-PCR method. Binding of HCV to cells was estimated by HCV RNA detection in cells 2 hr after inoculation and in the last wash of these cells. Successive virus passages in cells were carried out. All the cells studied were able to bind HCV but only AP61 and Vero cells provided evidence of replication and production of infectious virus: virus RNA was detected during 28 days post-infection in four successive virus passages. CD81 molecules, a putative HCV receptor, were detected by cytofluorometric analysis. Vero cells express CD81 molecules whereas these molecules were not detected on AP61 cells. It is suggested that other receptors are involved in HCV binding to Vero and AP61 cells.     

Effects of hindlimb unloading on ex vivo growth and osteogenic/adipogenic potentials of bone marrow-derived mesenchymal stem cells in rats

The goal of this study was to determine the effects of hindlimb unloading (HU) on the ex vivo growth and the osteogenic potential of mesenchymal stem cells (MSCs) from the femurs of rats. Microgravity was simulated by 28-day HU in male Sprague-Dawley (SD) rats, and the bone marrow (BM) was collected from hindlimb femurs of HU or control (CTL) rats. MSCs were isolated from BM and cultured for eight passages. Then MSCs at passages 2, 4, and 8 were induced for osteogenesis or adipogenesis. The results revealed that HU decreased the osteogenic potential of MSCs and also decreased the expression of osteoblast gene marker mRNAs in cells induced by osteogenic conditions. Meanwhile, the expression of Runx2 mRNA and the phosphorylation of ERK were also decreased. There were no significant differences of osteoblast gene marker and Runx2 mRNA expression between cells induced from different passages of MSCs in UH rats. Under adipogenic conditions, HU increased both the adipogenic potential of MSCs and the expression of adipocytic gene marker mRNAs in induced cells. HU also increased the expression of PPAR gamma 2 mRNA, but with no effect on the phosphorylation of p38MAPK. The adipogenic potential of MSCs and the expression of adipocytic gene marker mRNAs in induced cells decreased along with cell cultures under normal gravity. This suggests that the normal gravity during in vitro MSC culture and the centrifugal force produced during cell harvest after each passage could decrease the adipogenic potential of MSCs, but could not reverse the effect of HU on the osteogenic potential of MSCs.     

长期培养的人脐带间充质干细胞PCNA、IL-6、IL-11和galectin-3的表达

目的: 探讨长期培养的人脐带间充质干细胞(hUC-MSCs)增殖细胞核抗原(PCNA)、白细胞介素-6(IL-6)、白细胞介素-11(IL-11)和半乳糖凝集素-3(galectin-3) mRNA及蛋白表达的变化情况,为hUC-MSCs的实验研究和临床应用提供实验资料和理论依据。方法: 取剖宫产新生儿脐带,分离、传代培养hUC-MSCs;收集第3、8、18、28和33代细胞及培养上清,用qRT-PCR、ELISA及Western bloting检测PCNA、IL-6、IL-11和galectin-3 mRNA和蛋白水平。结果: (1) hUC-MSCs PCNA、IL-6、IL-11 mRNA及IL-6、IL-11蛋白的表达随培养传代次数增加而减少,第33代较第3代分别降低了33%、56%、37%和50.3%、58.9%,差异显著(均P<0.01)。(2)各代间galectin-3 mRNA表达无显著差异(P＞0.05),且各代间蛋白表达亦无明显差异。结论: (1)体外长期传代培养过程中hUC-MSCs增殖能力和支持造血能力可能逐渐减弱甚至丧失。(2)体外长期传代培养可能对hUC-MSCs的免疫调节功能无显著影响,这有待进一步的实验验证。     

Comparison of chick embryo liver and vero cell cultures for the isolation and growth of avian reoviruses

Twenty-two strains of avian reovirus, all of which had had several passages in avian embryonic cell cultures, produced CPE in Vero cells after 1 to 3 passages. However, even after five blind passages, reoviruses were not isolated in Vero cells from faecal or joint material already shown to contain reovirus by ' chick embryo liver (CELi) passage. Growth characteristics of CELi- or Vero-adapted reovirus strain R2 were compared. Even after 15 passages in Vero cells, strain R2 still replicated in CELi cells, and higher titres of virus were detected when CELi cells rather than Vero were used to titrate virus. The results indicated that Vero cells were unsuitable for the isolation of avian reoviruses from field material.     

AFP增强型四元复合体介导N-ras反义RNA抑制HepG2.2.15细胞成瘤性的研究

目的　观察AFP增强型四元复合体介导的N ras反义RNA转移系统对HBV转基因肝癌细胞系HepG2 .2 .15致瘤性的体内外抑制作用。方法　构建含有N ras反义RNA的AFP增强型四元复合体 ,体外瞬时转染HBV转基因HepG2 .2 .15细胞 ,流式细胞术检测转染前后N ras蛋白表达水平、细胞凋亡率及细胞周期的变化 ,同时建立稳定表达N ras反义RNA的肝癌细胞系HepG2 .2 .15 /as ras,绘制转染前后生长曲线。体内抑瘤试验分别以HepG2 .2 .15或HepG2 .2 .15 /as ras细胞制备荷瘤裸鼠模型 ,比较二者成瘤率。HepG2 .2 .15成瘤组局部瘤内注射N ras反义RNA四元复合体 ,研究其对肿瘤的抑制作用。结果　AFP增强型四元复合体介导N ras反义RNA体外瞬时转染HepG2 .2 .15细胞可显著降低胞内N ras蛋白的表达水平 (P <0 .0 5 ) ,使细胞生长停滞于G0 /G1期 ,且可诱导细胞凋亡。体内抑瘤实验显示 ,HepG2 .2 .15 /as ras细胞注射组成瘤率 ( 4 0 % )显著低于HepG2 .2 .15细胞注射组( 10 0 % )。瘤内注射N ras反义RNA四元复合体可使肿瘤体积明显缩小。结论　AFP增强型四元复合体介导的N ras反义RNA转移系统可降低HBV转基因肝癌细胞HepG2 .2 .15N ras蛋白的表达水平 ,逆转其恶性行为 ,体内外均可有效抑制肿瘤的生长增殖     

介导RA538与反义c-myc腺病毒对肿瘤细胞的作用及其分子机理

目的　比较全反式维甲酸诱导基因 RA5 38及反义 c- myc对人胃癌细胞的生物学特性 ,并探讨其作用的分子机理。方法　采用细胞生长曲线、DNA梯度降解试验、原位末端标记、流式细胞仪、逆转录 -聚合酶链反应、蛋白质印迹分析、裸鼠致瘤性、裸鼠皮下移植瘤模型实验等方法 ,对 RA5 38、反义 c- myc重组腺病毒在人胃癌细胞系 (SGC790 1)中的生物学作用及其分子机理进行体内外研究。结果　 RA5 38及反义 c- myc重组体腺病毒 (Ad- RA5 38及 Ad- ASc- myc)对 SGC790 1细胞生长抑制率分别为 76 .3%和 44 .1%。 DNA梯度降解试验、原位末端标记、流式细胞仪显示 Ad- RA5 38及 Ad- ASc- myc诱导 SGC790 1细胞凋亡。它们均能抑制SGC790 1细胞 c- myc、bcl- 2、cyclin D1基因表达 ,并刺激 bax基因表达 ,对 p5 3、p16、TGase、ras基因的表达没有影响。经 Ad- RA5 38及 Ad- ASc- myc处理的 SGC790 1细胞致瘤性消失。Ad- RA5 38及 Ad- ASc- myc对裸鼠皮下移植瘤模型瘤内注射能有效降低肿瘤的生长速度 ,生长抑制率分别为 6 0 .7%和 6 8.9%。结论　 Ad-RA5 38、Ad- ASc- myc对胃癌细胞具有显著的生长抑制及凋亡诱导作用。其作用是 c- myc、bcl- 2、bax、cyclin D1等一系列基因表达变化及其相互作用的结果 ,与 p5 3、p16、TGa     

端粒酶活性在骨髓间充质干细胞体外分化过程中的表达观察

为了探讨兔骨髓间充质干细胞体外增殖前后及诱导分化内皮细胞过程中端粒酶活性的表达及意义，我们联合应用密度梯度离心和贴壁培养法分离骨髓间充质干细胞，继而诱导其向内皮细胞方向分化，用TRAPeze ELISA法分别检测新鲜分离的骨髓细胞及骨髓间充质干细胞、原代培养的内皮样细胞及传代细胞端粒酶活性，结果发现新鲜分离的骨髓细胞及增殖前的骨髓间充质干细胞端粒酶活性低水平表达，一旦经过VEGF诱导分化，细胞端粒酶活性表达上调，在5代内其端粒酶活性不因细胞传代而下降或消失，说明骨髓间充质干细胞体外有限扩增和诱导分化时保持端粒酶活性，维持组织干细胞特性，为组织干细胞的临床研究奠定理论基础。     

Differential expression of osteogenic factors associated with osteoinductivity of human osteosarcoma cell lines

Differential expression of multiple osteogenic factors may be responsible for the different osteoinductivity of osteosarcoma cell lines. We compared in vivo osteoinductivity of human osteosarcoma cell lines (Saos-2 vs. U-2 OS) in nude mice, and their in vitro expression of various osteogenic factors of protein level by quantitative immunocytochemistry and mRNA level by RT-PCR and/or in situ hybridization. Saos-2 cells, but not U-2 OS, were osteoinductive in vivo. Significantly higher expression (independent t-test, all p < 0.005) of osteogenic factors were observed in Saos-2 cells compared with U-2 OS, which included bone morphogenetic proteins (particularly BMPs-2, 3, 4, and 7), transforming growth factor-beta (TGF-beta), BMP receptor (BMPR)-1A, receptor-regulated Smads (R-Smads), Smads 1, 2, and 5, and common-mediator Smad (Co-Smad), Smad 4. In contrast, U-2 OS cells expressed higher levels of inhibitory Smad 6 (I-Smad) protein than Saos-2 cells (p < 0.001). These results suggest that a combination of osteogenic factors (BMPs, TGF-beta, BMPRs, and R/Co-Smads) against I-Smad may play important roles in the Saos-2 cell osteoinductivity. This may have a clinical implication in selecting key osteogenic factors for combined therapy for bone defect diseases. The characterized cell lines can be used as positive and negative controls for the assessments of both in vitro and in vivo bone formation capabilities of designed tissues or biomaterials.