Immunophenotypic, immunocytochemistry, ultrastructural, and cytogenetic characterization of mesenchymal stem cells from equine bone marrow

The aim of this study was to isolate, culture, and characterize mesenchymal stem cells (MSCs) from horse bone marrow (BM) using the techniques of flow cytometry, immunocytochemistry, cytogenetics, and electron microscopy. Immunophenotypic analysis revealed the presence of MSCs with high expression of the CD90 marker, lower expression of the CD44 marker, and absent expression of the CD34 marker. In assays of differentiation, the positive response to osteogenic (OST), chondrogenic (CDG), and adipogenic (ADP) differentiation signals was observed and characterized by deposition of calcium-rich extracellular matrix (OST), proteoglycans and collagen II (CDG) and intracellular deposition of fat drops (ADP). In immunocytochemical characterization, MSCs were immunopositive for CD44, vimentin, and PCNA, and they were negative for CD13. In the ultrastructural analysis of MSCs, the most outstanding characteristic was the presence of rough endoplasmic reticulum with very dilated cisterns filled with a low electrodensity material. Additionally, MSCs had normal karyotypes (2n=64) as evidenced by cytogenetic analysis, and aneuploidy in metaphase was not observed. The protocols for isolating, culturing, and characterizing equine MSCs used in this study were shown to be appropriate for the production of a cell population with a good potential for differentiation and without aneuploidy that can be used to study future cellular therapies. © 2013 Wiley Periodicals, Inc.

A high-fat diet increases interleukin-3 and granulocyte colony-stimulating factor production by bone marrow cells and triggers bone marrow hyperplasia and neutrophilia in wistar rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Equine mesenchymal stem cells from bone marrow, adipose tissue and umbilical cord: immunophenotypic characterization and differentiation potential

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Bone Marrow'S Harvest in The Coxal Tuberosity for Isolation and Culture of Mesenchymal Stem Cells of Buffaloes (Bubalus Bubalis)

Several studies with mesenchymal stem cells (MSCs) have been developed in many species because of its ability to differentiate into other mesoderm lineages, capacity of self-regeneration, low immunogenicity, paracrine, anti-inflamatory, immunomodulatory and antiapoptotic effects which make then a promissory source to be used in therapeutic strategies. The aim of this study is to report the technique of harvest of bone marrow (BM) in the coxal tuberosity (CT) of buffaloes. For this, the animals were selected, identified and contained in a stock. Then trichotomy was performed in the region corresponding to the CT. After identifying the anatomic site it was performed antisepsis, local anesthetic block and introduction of a myelogram's needle (Lang(R)) for BM aspiration. Once the needle was firmly fixed in the CT, the mandril was removed and proceeded to BM aspiration with a syringe (20 mL) containing 1 ml of heparin at 1000 IU / mL and 1 mL of PBS. After the collection, each sample collected was manually homogenized, identified and referred to the LRACT - FMVZ / UNESP-BRAZIL for the correct processing. The anatomical site tested showed to be an alternative site of harvest of BM once provided the appropriate isolation and culture of the mononuclear fraction. Moreover, the procedure was performed without difficulty and with great security. Based on this, it can be conclude that CT is an excellent anatomical site for isolation and culture of MSCs and the proposed technique is viable and feasible to be held in buffaloes.

Isolation, Culture and Differentiation of Buffaloes Bone Marrow Mesenchymal Stem Cells Obtained from the Coxal Tuberosity

Currently, much attention has been devoted to the renewal of knowledge about Stem Cells and Cell Therapy in domestic species. In this sense, the present work aimed to develop a methodology for collecting, processing and cultivation of mesenchymal stem cells obtained from bone marrow of coxal tuberosity in buffaloes. The collection was performed using a Komiyashiki needle, which was introduced in the coxal tuberosity and the bone marrow aspirated into a heparinized syringe with the aid of negative pressure. Directly after collection samples were processed at the laboratory at FMVZ - UNESP. The samples took approximately 32 days to reach 80% confluence, when the first passage and differentiation was performed. To confirm the mesenchymal origin, cells were induced to differentiate into adipogenic and osteogenic lineages. Samples showed morphological changes during differentiation protocol, but not all presented production of extracellular deposits of calcium or intracellular fat droplets, observed after staining with Alizarin Red and Oil Red respectively. Compared with the material obtained from other species and processed in the same laboratory, the primary culture was longer. Therefore, more studies are needed to standardize the age of animals used and to test other inducers of cell differentiation.

Bone marrow mesenchymal stem cells stimulated by bFGF up-regulated protein expression in comparison with periodontal fibroblasts in vitro

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Feasibility and safety of intrathecal transplantation of autologous bone marrow mesenchymal stem cells in horses

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Antiproliferative Effects of Fluoxetine on Colon Cancer Cells and in a Colonic Carcinogen Mouse Model

The antidepressant fluoxetine has been under discussion because of its potential influence on cancer risk. It was found to inhibit the development of carcinogen-induced preneoplastic lesions in colon tissue, but the mechanisms of action are not well understood. Therefore, we investigated anti-proliferative effects, and used HT29 colon tumor cells in vitro, as well as C57BL/6 mice exposed to intra-rectal treatment with the carcinogen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) as models. Fluoxetine increased the percentage of HT29 cells in the G(0)/G(1) phase of cell-cycle, and the expression of p27 protein. This was not related to an induction of apoptosis, reactive oxygen species or DNA damage. In vivo, fluoxetine reduced the development of MNNG-induced dysplasia and vascularization-related dysplasia in colon tissue, which was analyzed by histopathological techniques. An anti-proliferative potential of fluoxetine was observed in epithelial and stromal areas. It was accompanied by a reduction of VEGF expression and of the number of cells with angiogenic potential, such as CD133, CD34, and CD31-positive cell clusters. Taken together, our findings suggest that fluoxetine treatment targets steps of early colon carcinogenesis. This confirms its protective potential, explaining at least partially the lower colon cancer risk under antidepressant therapy.

The Aurora A and B kinases are up-regulated in bone marrow-derived chronic lymphocytic leukemia cells and represent potential therapeutic targets

Background The malignant B cells in chronic lymphocytic leukemia receive signals from the bone marrow and lymph node microenvironments which regulate their survival and proliferation. Characterization of these signals and the pathways that propagate them to the interior of the cell is important for the identification of novel potential targets for therapeutic intervention. Design and Methods We compared the gene expression profiles of chronic lymphocytic leukemia B cells purified from bone marrow and peripheral blood to identify genes that are induced by the bone marrow microenvironment. Two of the differentially expressed genes were further studied in cell culture experiments and in an animal model to determine whether they could represent appropriate therapeutic targets in chronic lymphocytic leukemia. Results Functional classification analysis revealed that the majority of differentially expressed genes belong to gene ontology categories related to cell cycle and mitosis. Significantly up-regulated genes in bone marrow-derived tumor cells included important cell cycle regulators, such as Aurora A and B, survivin and CDK6. Down-regulation of Aurora A and B by RNA interference inhibited proliferation of chronic lymphocytic leukemia-derived cell lines and induced low levels of apoptosis. A similar effect was observed with the Aurora kinase inhibitor VX-680 in primary chronic lymphocytic leukemia cells that were induced to proliferate by CpG-oligonucleotides and interleukin-2. Moreover, VX-680 significantly blocked leukemia growth in a mouse model of chronic lymphocytic leukemia. Conclusions Aurora A and B are up-regulated in proliferating chronic lymphocytic leukemia cells and represent potential therapeutic targets in this disease.

Forced Expression of Nanog in Human Bone Marrow-Derived Endothelial Cells Activates Other Six Pluripotent Genes

Human endothelial cells (ECs) have the ability to make up the lining of blood vessels. These cells are also capable of neovascularization and revascularization and have been applied in various clinical situations. With the aim of understanding the effect of NANOG superexpression on ECs, we transduced the Nanog gene into the ECs. Nanog is highly expressed in embryonic stem cells (ESCs) and is essential for pluripotency and self-renewal. However, Nanog can also be expressed in somatic stem cells, and this gene is related to great expansion capacity in vitro. We found that ECs expressing Nanog showed expression of other stemness genes, such as Sox2, FoxD3, Oct4, Klf4, c-myc, and beta-catenin, that are not normally expressed or are expressed at very low levels in ECs. Nanog is one of the stemness genes that can activate other stemness genes, and the upregulation of the Nanog gene seems to be critical for reprogramming cells. In this study, the introduction of Nanog was sufficient to alter the expression of key genes of the pluripotent pathway. The functional importance of Nanog for altering the cell expression profile and morphology was clearly demonstrated by our results.

Micromass co-culture of human articular chondrocytes and human bone marrow mesenchymal stem cells to investigate stable neocartilage tissue formation in vitro

Cell therapies for articular cartilage defects rely on expanded chondrocytes. Mesenchymal stem cells (MSC) represent an alternative cell source should their hypertrophic differentiation pathway be prevented. Possible cellular instruction between human articular chondrocytes (HAC) and human bone marrow MSC was investigated in micromass pellets. HAC and MSC were mixed in different percentages or incubated individually in pellets for 3 or 6 weeks with and without TGF-beta1 and dexamethasone (±T±D) as chondrogenic factors. Collagen II, collagen X and S100 protein expression were assessed using immunohistochemistry. Proteoglycan synthesis was evaluated applying the Bern score and quantified using dimethylmethylene blue dye binding assay. Alkaline phosphatase activity (ALP) was detected on cryosections and soluble ALP measured in pellet supernatants. HAC alone generated hyaline-like discs, while MSC formed spheroid pellets in ±T±D. Co-cultured pellets changed from disc to spheroid shape with decreasing number of HAC, and displayed random cell distribution. In -T-D, HAC expressed S100, produced GAG and collagen II, and formed lacunae, while MSC did not produce any cartilage-specific proteins. Based on GAG, collagen type II and S100 expression chondrogenic differentiation occurred in -T-D MSC co-cultures. However, quantitative experimental GAG and DNA values did not differ from predicted values, suggesting only HAC contribution to GAG production. MSC produced cartilage-specific matrix only in +T+D but underwent hypertrophy in all pellet cultures. In summary, influence of HAC on MSC was restricted to early signs of neochondrogenesis. However, MSC did not contribute to the proteoglycan deposition, and HAC could not prevent hypertrophy of MSC induced by chondrogenic stimuli.