[Show abstract][Hide abstract] ABSTRACT: Paclitaxel resistance is a major obstacle for the treatment of ovarian cancer. The chemoresistance mechanisms are partly related to the mitochondria. Identification of the relevant proteins in mitochondria helps clarify the possible mechanisms and select effective chemotherapy for such patients. In the present study, mitochondria from two paclitaxel-sensitive human ovarian cancer cell lines (SKOV3 and A2780) and their corresponding resistant cell lines (SKOV3-TR and A2780-TR) were isolated. Guanidine-modified acetyl-stable isotope labelling and liquid chromatography-hybrid linear ion trap Fourier-transform ion cyclotron resonance mass spectrometry (LC-FTICR MS) were performed to find the expressed differential proteins. Comparative proteomic analysis revealed that 8 differentially expressed proteins in the ovarian cancer cells and their paclitaxel-resistant sublines. Among them, mimitin and 14-3-3 ζ/δ were selected for further research. The effects of mimitin and 14-3-3 ζ/δ were explored using specific siRNAs interference in ovarian cancer cell lines and immunohistochemistry in human tissue specimens. The down-regulation of mimitin and 14-3-3 ζ/δ using specific siRNAs in paclitaxel-resistant ovarian cancer cells led to increasing the resistance index to paclitaxel. Multivariate analyses demonstrated that lower expression levels of the mimitin and 14-3-3 ζ/δ proteins were positively associated with shorter progression-free survival and overall survival in patients with primary ovarian cancer (mimitin: PFS: P = 0.041, OS: P = 0.003; 14-3-3 ζ/δ: PFS: P = 0.031, OS: P = 0.011). Mimitin and 14-3-3 protein ζ/δ are potential markers of paclitaxel resistance and prognostic factors in ovarian cancer. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: The clinical acute graft-versus-host disease (GvHD)-therapy of mesenchymal stem cells (MSCs) is not as satisfactory as expected. Secondary lymphoid organs (SLOs) are the major niches serve to initiate immune responses or induce tolerance. Our previous study showed that CCR7 guide murine MSC line C3H10T1/2 migrating to SLOs. In this study, CCR7 gene was engineered into murine MSCs by lentivirus transfection system (MSCs/CCR7). The immunomodulatory mechanism of MSCs/CCR7 was further investigated. Provoked by inflammatory cytokines, MSCs/CCR7 increased the secretion of nitric oxide and calmed down the T cell immune response in vitro. Immunofluorescent staining results showed that transfused MSCs/CCR7 can migrate to and relocate at the appropriate T cell-rich zones within SLOs in vivo. MSCs/CCR7 displayed enhanced effect in prolonging the survival and alleviating the clinical scores of the GvHD mice than normal MSCs. Owing to the critical relocation sites, MSCs/CCR7 co-infusion potently made the T cells in SLOs more naïve like, thus control T cells trafficking from SLOs to the target organs. Through spoiling the fourth supplemental Billingham's tenet, MSCs/CCR7 potently inhibited the development of GvHD. The study here provides a novel therapeutic strategy of MSCs/CCR7 infusion at a low dosage to give potent immunomodulatory effect for clinical immune disease therapy.
[Show abstract][Hide abstract] ABSTRACT: Inefficient homing of systemically infused mesenchymal stem cells (MSCs) limits the efficacy of existing MSC-based clinical graft-versus-host disease (GvHD) therapies. Secondary lymphoid organs (SLOs) are the major niches for generating immune responses or tolerance. MSCs home to a wide range of organs, but rarely to SLOs after intravenous infusion. Thus we hypothesized that targeted migration of MSCs into SLOs may significantly improve their immunomodulatory effect. Here, chemokine receptor 7 (CCR7) gene, encoding a receptor that specifically guides migration of immune cells into SLOs, was engineered into a murine MSC line C3H10T1/2 by retrovirus transfection system (MSCs/CCR7). We found that infusion of MSCs/CCR7 potently prolonged the survival of GvHD mouse model. The infused MSCs/CCR7 migrate to SLOs, relocate in close proximity with T lymphocytes, therefore, potently inhibited their proliferation, activation and cytotoxicity. Natural killer (NK) cells contribute to the early control of leukemia relapse. Though MSCs/CCR7 inhibited NK cell activity in vitro co-culture, they did not impact on the proportion and cytotoxic capacities of NK cells in the peripheral blood of GvHD mice. In an EL4 leukemia cell loaded GvHD model, MSCs/CCR7 infusion preserved the graft-versus-leukemia (GvL) effect. In conclusion, this study demonstrates that CCR7 guides migration of MSCs to SLOs and thus highly intensify their in vivo immunomodulatory effect while preserving the GvL activity. This exciting therapeutic strategy may improve the clinical efficacy of MSC based therapy for immune diseases. Stem Cells 2014.
[Show abstract][Hide abstract] ABSTRACT: Mesenchymal stem cells (MSCs) have been shown to be highly immunosuppressive and have been employed to treat various immune disorders. However, the mechanisms underlying the immunosuppressive capacity of MSCs are not fully understood. We found the suppressor of cytokine signaling 1 (SOCS1) was induced in MSCs treated with inflammatory cytokines. Knockdown of SOCS1 did not bring much difference on the proliferation and differentiation properties of MSCs. However, MSCs with SOCS1 knockdown exhibited enhanced immunosuppressive capacity, showing as inhibiting T cell proliferation at extremely low ratio (MSC to T) in vitro, significantly promoting tumor growth and inhibiting delayed-type hypersensitivity response in vivo. We further demonstrated that SOCS1 inhibited the immunosuppressive capacity of MSCs by reducing inducible nitric oxide synthase (iNOS) expression. Additionally, we found the significantly lower SOCS1 expression and higher nitric oxide (NO) production in MSCs isolated from synovial fluid of rheumatoid arthritis patients. Collectively, our data revealed a novel role of SOCS1 in regulating the immune modulatory activities of MSCs.
[Show abstract][Hide abstract] ABSTRACT: This study was purposed to establish a convenient and efficient method for isolating and culturing mouse bone marrow mesenchymal stem cells (MSC). The femurs and tibias of mouse were taken under sterile condition. MSC were isolated and cultured with flushing- out bone marrow or collagenase-digested bone fragment or bone marrow plus bone fragment. MSC colony number and size were compared. Immunophenotype and differentiation ability were tested to identify MSC. The results showed that colonies from bone marrow plus bone fragment group came out earliest and the colony number was 20 ± 4 at day 4; there were 11.5 ± 2.5 colonies in collagenase-digested bone fragment group and 9.5 ± 1.5 in flushing- out bone marrow group. The total cell yields of MSC after passaging showed best in bone marrow plus bone fragment group. Flow cytometry data showed the cultured cells expressed Sca-1, CD44 and CD29, not expressed pan-leukocyte surface marker CD45 and endothelial cell marker CD31. The isolated and cultured MSC could differentiate into osteoblast at the osteogenic differentiation condition, or adipocyte at adipogenic differentiation condition. It is concluded that the method of bone marrow plus bone fragment is convenient and efficient for isolating and culturing MSC.
No preview · Article · Nov 2013 · Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology
[Show abstract][Hide abstract] ABSTRACT: Taxol is a powerful chemotherapy agent leading to mitotic arrest and cell death; however, its clinical efficacy has been hampered due to the development of drug resistance. Taxol specifically targets the cell cycle. Progress through mitosis (M stage) is an absolute requirement for drug-induced death because cell death is markedly reduced in cells blocked at the G1-S transition. The measured doubling time for ovarian cancer cells is about 27h. As such, during treatment with Taxol most of the cells are not in the M stage of the cell cycle. Thus, the effect of cell-cycle synchronization was investigated in regard to reversing Taxol resistance in ovarian cancer cells.
Giemsa-Wright staining was used for assessing the morphology of the cells. The doubling time of the cells was calculated using formula as follows: Td = In2/slope. The resistant index and cell cycle were measured via MTT assays and flow cytometry. Thymidine was used to induce cell-cycle synchronization, and cell apoptosis rates following exposure to Taxol were measured using a flow cytometer.
The growth doubling time of two Taxol-resistant cell lines were longer than that of Taxol-sensitive cells. Apoptotic rates in Taxol-sensitive and -resistant cell lines after synchronization and exposure to Taxol were all higher compared to unsynchronized controls (p <0.05).
Synchronization of the cell-cycle resulted in an increased effectiveness of Taxol toward ovarian cancer cell lines. We speculated that formation of drug resistance toward Taxol in ovarian cancer could be partly attributed to the longer doubling time of these cells.
Preview · Article · Jul 2013 · Cancer Cell International
[Show abstract][Hide abstract] ABSTRACT: The acquisition of chemoresistance is a major therapeutic obstacle in the clinical treatment of ovarian cancer. Diagnosing chemoresistance in ovarian cancer patients at an early stage is necessary for prognosis, but at present significant proteins related to chemoresistance that may indicate and reverse chemoresistance in human ovarian cancer have not been discovered. In this study, we demonstrated that the protein, phosphorylated cofilin 1 (p-CFL1) correlates with taxol resistance in human ovarian cancer cells. The total proteins of two sensitive (SKOV3 and A2780) and three taxol-resistant (SKOV3/TR2500, SKOV3/TR30 and A2780/TR) human ovarian cancer cell lines were isolated by 2-dimensional gel electrophoresis (2-DE). Twenty-two protein spots in all samples were revealed to be significantly different in spot intensity by statistical analysis, 16 of which were identified using matrix-assisted laser desorption ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS). Cofilin 1 (CFL1) was selected as a candidate which may play an important role in taxol resistance. Higher expression levels of p-CFL1 in taxol-resistant cells were demonstrated. Furthermore, the levels of p-CFL1 in primary human ovarian cancer tissues were shown to be significantly higher in chemoresistant cases compared to those in chemosensitive ones. These findings suggest that p-CFL1 is upregulated in taxol-resistant ovarian cancer and this upregulation is a chara-cteristic of taxol resistance both in vitro and in vivo. However, the mechanisms need to be further elucidated.
[Show abstract][Hide abstract] ABSTRACT: This study was purposed to investigate the regulatory effects of differentiating mesenchymal stem cells (MSC) on osteoclast formation. The MSC from mouse compact bones were cultured and induced into osteoblasts and adipocytes for one week. To test their regulatory effect on osteoclastogenesis, osteogenically differentiated and adipogenically differentiated MSC were co-cultured with CD11b(+) monocytes and osteoclasts were identified with in situ tartrate-resistant acid phosphatase (TRAP) staining. The results showed that differentiated MSC supported osteoclastogenesis but the osteoclast supporting capacity of osteogenically differentiated MSC decreased as compared with undifferentiated MSC. More interestingly, the adipogenically differentiated MSC significantly promoted osteoclasts formation when co-cultured with monocytes. It is concluded that the regulatory effect of MSC on osteoclast formation has changed while they have differentiated into different types of cells. The findings indicate that MSC may exert alternative effect on osteoclastogenesis by differentiation to descendant cells.
No preview · Article · Oct 2012 · Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology
[Show abstract][Hide abstract] ABSTRACT: This study was purposed to investigate the effect of RUNX1 on transcription activity of WNT5A promoter in mouse bone marrow derived mesenchymal stem cells (MSC), and to explore the mechanism by which bone marrow environments regulate MSC. RT-PCR was used to detect the expression of RUNX1 in MSC isolated from mouse bone marrow and cultured in vitro; the chromatin immunoprecipitation (ChIP) was used to investigate the direct in vivo interaction between the RUNX1 and WNT5A promoter; retrovirus system was utilized to introduce the RUNX1 gene into MSC to detect the regulation of RUNX1 on the transcription activity of WNT5A promoter. The results showed that mouse bone marrow derived MSC was positive for Oil Red O, van Kossa and toluidine blue staining respectively and RUNX1 expressed in MSC. WNT5A promoter could be bound by RUNX1, and the expression level of WNT5A was enhanced with the increase of RUNX1. It is concluded that RUNX1 expresses in mouse bone marrow derived MSC, WNT5A is a direct target gene of RUNX1 and its transcriptional activity is regulated by RUNX1.
No preview · Article · Oct 2011 · Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology
[Show abstract][Hide abstract] ABSTRACT: This study was aimed to investigate whether endothelium-specific deletion of PTEN can affect hemangioblast development in the AGM region of mouse embryos. Based on Cre/loxP system, the Tie2CrePten(loxp/loxp) and Tie2CrePten(loxp/wt) mouse embryos were obtained. The genotype was identified by PCR. After treated with type I collagenase, the AGM region was dispersed into single-cell suspension, and then was cultured in blast colony-forming cell (BL-CFC) media. The number of BL-CFC was counted 4 or 5 days later. The hematopoietic capacity of BL-CFC was detected in methylcellulose culture system and the endothelial potential was assessed by tube-like structure formation on Matrigel. The results showed that the number of BL-CFC in AGM region of Tie2CrePten(loxp/loxp) mouse embryo decreased as compared with Tie2CrePten(loxp/wt) embryo. Whereas the hematopoietic capacity of mutant BL-CFC was enhanced, the endothelial potential, as evaluated by tube-like structure formation in vitro, was significantly reduced. It is concluded that the endothelial PTEN is capable of exerting regulatory functions on both the numbers and the dual potential of hemangioblast in mouse AGM region.
No preview · Article · Oct 2011 · Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology
[Show abstract][Hide abstract] ABSTRACT: This study was aimed to investigate the effect of RPMI 1640 and IMDM on the development of human peripheral blood monocyte-derived dendritic cells. Under the same cytokines and culture conditions, the different medium types were tested, and the morphology of mature and immature dendritic cells was observed by microscopy, the cell phenotype and endocytosis ability were detected by flow cytometry. Furthermore, the immunoregulatory function of various DC was analyzed by mixed lymphocyte reaction (MLR), the expression of cytokine in culture supernatant of MLR system was also analyzed by Bio-plex technology. The results showed that there were no difference in morphology, CD14, CD83 expression and endocytosis ability between IMDM-cultured DC and RPMI-1640 medium-cultured DC, but there was a lower expression of CD1a in IMDM-cultured DC. Moreover, DC cultured with IMDM displayed a significant reduction in stimulating T cell proliferation, and highly expressed IL-6, IL-8 and IL-10, but low expressed IL-12. It is concluded that the different cultural mediums can induce DC with different functions and DC cultured with IMDM may correlated with induction of immune tolerance. The results of this study will provide a new idea for DC clinical application.
No preview · Article · Jul 2011 · Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology
[Show abstract][Hide abstract] ABSTRACT: Early detection of resistance to platinum-based therapy is critical for improving the treatment of ovarian cancers. We have previously found that increased expression of annexin A3 is a mechanism for platinum resistance in ovarian cancer cells. Here we demonstrate that annexin A3 can be detected in the culture medium of ovarian cancer cells, particularly these cells that express high levels of annexin A3. Levels of annexin A3 were then determined in sera from ovarian cancer patients using an enzyme-linked immunosorbent assay. Compared with those from normal donors, sera from ovarian cancer patients contain significantly higher levels of annexin A3. Furthermore, serum levels of annexin A3 were significantly higher in platinum-resistant patients than in platinum-sensitive patients. To gain insight into the mechanism of secretion, the ovarian cancer cell lines were examined using both transmission electron microscopy and immunoelectron microscopy. Compared with parent cells, there are significantly more vesicles in the cytoplasm of ovarian cancer cells that express high levels of annexin A3, and at least some vesicles are annexin A3-positive. Moreover, some vesicles appear to be fused with the cell membrane, suggesting that annexin A3 secretion may be associated with exocytosis and the release of exosomes. This is supported by our observation that ovarian cancer cells expressing higher levels of annexin A3 released increased numbers of exosomes. Furthermore, annexin A3 can be detected in exosomes released from cisplatin-resistant cells (SKOV3/Cis) by immunoblotting and immunoelectron microscopy.
Full-text · Article · Mar 2011 · Journal of Cellular and Molecular Medicine
[Show abstract][Hide abstract] ABSTRACT: This study was aimed to investigate the effect of human umbilical vein endothelial cells (HUVEC) on dendritic cell (DC) development. First, HUVEC were isolated from human umbilical cord by collagenase digestion, and then the morphology, immunophenotypes and functions were identified. Furthermore, the HUVEC were cocultured with CD14(+) monocytes under the cytokine condition for detecting the influence of HUVEC on differentiation of CD14(+) cells to DC. The phenotype of dendritic cells derived from CD14(+) cells was analyzed by flow cytometry, the immunoregulatory function of DC was tested by mixed lymphocyte reaction (MLR). The change of IL-6 and VEGF as well as EPK and p38 signal pathway were analyzed by neutral antibody experiment and Western blot. The results showed that HUVEC isolated from human umbilical cord were characterized by spindle-shaped morphology, homogenous immunophenotypes (vWF(+)CD31(+)CD73(+)CD45(-)HLA-DR(-)CD86(-)CD34(low)), Dil-Ac-LDL incorporation ability and forming capillary-like structures. Following stimulation with granulocyte-macrophage colony-stimulating factor (GM-CSF) plus interleukin-4 (IL-4), HUVEC cocultures could inhibit the initial differentiation of CD14(+) monocyte to DC. Interestingly, IL-6 and VEGF enhanced the suppression effect of HUVEC on generation of DC via activation of the ERK or p38 mitogen activated protein kinase pathway. It is concluded that HUVEC are involved in DC development and can suppress the differentiation of monocyte to DC.
No preview · Article · Mar 2011 · Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology
[Show abstract][Hide abstract] ABSTRACT: Mesenchymal stem cells (MSCs) represent powerful tools for regenerative medicine for their differentiation and migration capacity. However, ontogeny and migration of MSCs in mammalian mid-gestation conceptus is poorly understood. We identified canonical MSCs in the mouse embryonic day (E) 11.5 dorsal aorta (DA). They possessed homogenous immunophenotype (CD45(-)CD31(-)Flk-1(-)CD44(+)CD29(+)), expressed perivascular markers (α-SMA(+)NG2(+)PDGFRβ(+)PDGFRα(+)), and had tri-lineage differentiation potential (osteoblasts, adipocytes, and chondrocytes). Of interest, MSCs were also detected in E12.5-E13.5 embryonic circulation, 24 hr later than in DA, suggesting migration like hematopoietic stem cells. Functionally, E12.5 embryonic blood could trigger efficient migration of DA-MSCs through platelet-derived growth factor (PDGF) receptor-, transforming growth factor-beta receptor-, but not basic fibroblast growth factor receptor-mediated signaling. Moreover, downstream JNK and AKT signaling pathway played important roles in embryonic blood- or PDGF-mediated migration of DA-derived MSCs. Taken together, these results revealed that clonal MSCs developed in the mouse DA. More importantly, the embryonic circulation, in addition to its conventional transporting roles, could modulate migration of MSC during early embryogenesis.
Full-text · Article · Jan 2011 · Developmental Dynamics
[Show abstract][Hide abstract] ABSTRACT: Resistance to platinum-based chemotherapy is the major obstacle to successful treatment of ovarian cancer. It is evident that mitochondrial defects and the dysfunctions of oxidative phosphorylation and energy production in ovarian cancer cells were directly related to their resistance to platinum drugs. Using 2-D DIGE, we compared mitochondrial proteins from two platinum-sensitive human ovarian cancer cell lines (SKOV3 and A2780) with that of four platinum-resistant sublines (SKOV3/CDDP, SKOV3/CBP, A2780/CDDP, and A2780/CBP). Among the 236 differentially expressed spots, five mitochondrial proteins (ATP-α, PRDX3, PHB, ETF, and ALDH) that participate in the electron transport respiratory chain were identified through mass spectrometry. All of them are downregulated in one or two of the platinum-resistant cell lines. Three proteins (ATP-α, PRDX3, and PHB) were validated by using western blot and immunohistochemistry. There is a significant decrease of PHB in tumor tissues from ovarian cancer patients who were resistant to platinum-based chemotherapies. This is the first direct mitochondrial proteomic comparison between platinum-sensitive and resistant ovarian cancer cells. These studies demonstrated that 2-D DIGE-based proteomic analysis could be a powerful tool to investigate limited mitochondrial proteins, and the association of PHB expression with platinum resistance indicates that mitochondria defects may contribute to platinum resistance in ovarian cancer cells.
[Show abstract][Hide abstract] ABSTRACT: Recent data have demonstrated that mesenchymal stem cells (MSCs) have potent immune regulation capacity in vitro, enhancing their therapeutic appeal for their utilisation in the management of acute graft-versus-host disease (aGvHD). However, their immunoregulatory activity in vivo is largely unknown.
Using murine compact bone-derived MSCs in an aGvHD model, the phenotypic status of splenocytes of aGvHD and aGvHD+MSC groups of mice were examined by flow cytometry.
MSC infusion decreased the expression of MHC-II and CD69 molecules on splenic CD11b+ cells of aGvHD mice, which resulted in decreased maturation of antigen-presenting cells. Moreover, the down-regulated ratio of CD3+CD69+ to CD3+ cells, leading to restrained early activation and effector T-cell formation, resulted in the enhancement of the absolute and relative number of splenic CD3+ cells by MSCs co-transfer.
This study demonstrated that MSCs can inhibit the three developmental stages of aGvHD.
No preview · Article · Sep 2010 · In vivo (Athens, Greece)
[Show abstract][Hide abstract] ABSTRACT: This study was purposed to investigate the effect of mitogen-activated protein kinase (MAPK) pathway on the osteoblast differentiation of mouse mesenchymal stem cells (MSCs), MSCs were isolated from mouse compact bone and serially passaged. After being cultured in osteogenic induction medium, the phosphorylation levels of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 were detected by Western blot. The effects of corresponding pathway inhibitors including PD98059, JNK II and SB203580 on alkaline phosphatase (ALP) and calcium accumulation in the osteoblastic differentiation of MSCs were determined by ALP staining and von kossa staining respectively. The results showed that MAPK pathway including ERK, JNK and p38 was activated in differentiation of MSCs into osteoblasts. ALP activity of MSCs increased in the early phase by addition of PD98059 treatment, whereas ALP activity and calcium accumulation were not observed via JNK II treatment. However, SB203580 strongly inhibited the ALP expression and the calcium accumulation. It is concluded that p38 plays a positive role in the osteogenic differentiation of MSCs, and ERK is probably a negative factor at the early phase of differentiation, but the effect of JNK is not essential.
No preview · Article · Aug 2010 · Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology
[Show abstract][Hide abstract] ABSTRACT: Mesenchymal stem cells (MSCs) are multipotent stem cells capable of differentiating into various cell types, including osteocytes, chondrocytes, adipocytes, myocytes, and tenocytes. However, the difficulty or failure in expanding the mouse MSCs in vitro greatly hampered important research in animal models. The OP9, a stromal cell line from mouse bone marrow, has hematopoietic supportive capacity. Here, we report that the OP9 has the immunophenotype (CD45(-), CD11b(-), FLK-1(-), CD31(-), CD34(-), CD44(+), CD29(+), Sca-1(+), CD86(-), and MHCII(-)) identical to canonical mouse MSCs. The expression of CD140a(+), CD140b(+), alpha-SMA(+) and Calponin(+) suggested the perivascular origin of OP9. Functionally, the OP9 had strong clonogenic ability and could be induced into osteocytes, chondrocytes and adipocytes. The lymphocyte transformation test (LTT) and mixed leukocyte reaction (MLR) showed that the OP9 could suppress T lymphocyte proliferation stimulated by nonspecific mitogens (PHA) or allogeneic lymphocytes (BALB/c T cells). Finally, the migration of OP9 could be efficiently induced by bFGF, IGF-1, IL-3, PDGF-BB, TGF-beta1 and TGF-beta3. In conclusion, the OP9 were bona fide MSCs, and such homogenous cell line will be helpful to delineate biological features of MSCs at the stem cell level.
Full-text · Article · Jul 2010 · Journal of Genetics and Genomics
[Show abstract][Hide abstract] ABSTRACT: Unlike humans, mouse bone marrow-derived mesenchymal stem cells (MSCs) cannot be easily harvested by adherence to plastic owing to the contamination of cultures by hematopoietic cells. The design of the protocol described here is based on the phenomenon that compact bones abound in MSCs and hematopoietic cells exist in the marrow cavities and the inner interfaces of the bones. The procedure includes flushing bone marrow out of the long bones, digesting the bone chips with collagenase type II, deprivation of the released cells and culturing the digested bone fragments, out of which fibroblast-like cells migrate and grow in the defined medium. The entire technique requires 5 d before the adherent cells are readily passaged. Further identification assays confirm that these cells are MSCs. We provide an easy and reproducible method to harvest mouse MSCs that does not require depletion of hematopoietic cells by sorting or immunomagnetic techniques.