An elevated number of differentiated osteoblast colonies can be obtained from rat bone marrow stromal cells using a gradient isolation procedure

RNF213 gene silencing upregulates transforming growth factor β1 expression in bone marrow-derived mesenchymal stem cells and is involved in the onset of Moyamoya disease

Moyamoya disease (MMD) is a chronic and progressive cerebrovascular occlusion disease, the precise etiology of which is poorly understood. Ring finger protein 213 (RNF213) has been previously identified as a susceptibility gene that serves an important role in angiogenesis, where it has been shown to be closely associated with the onset of MMD. Patients with MMD exhibit increased expression levels of various pro-inflammatory molecules and angiogenic factors. Under certain conditions, bone marrow mesenchymal stem cells (BMSCs) have the ability to differentiate to form neuron-like and microglia-like cells. In the present study, a total of 40 MMD patients and 40 healthy individuals were enrolled. ELISA assays revealed that the expression of serum vascular endothelial growth factor (VEGF) and transforming growth factor β1 (TGF-β1) were higher than that in healthy controls. Furthermore, rat BMSCs (rBMSCs) were isolated and cultured using the whole bone marrow adherence method, which were then phenotyped using flow cytometry. Osteogenic and adipogenic differentiation were determined by using Alizarin red and oil red O staining, respectively. RNF213 was knocked-down using a lentivirus-mediated short hairpin RNA system in passage three rBMSCs, and successful transfection of the RNF213 was confirmed by RT-qPCR and fluorescence imaging. The expression levels of VEGF and TGF-β1 in these rBMSCs were measured on days 7 and 14, respectively. The results demonstrated that RNF213 knockdown upregulated TGF-β1 at both protein and mRNA levels, but did not exert any effect on VEGF gene expression. In conclusion, these findings suggested that that RNF213 knockdown may contribute to aberrant TGF-β1 expression via a pathway that remains to be unidentified, indicating that quantitative changes in RNF213 gene expression may serve an important role in the pathogenesis of MMD.

Blood-brain barrier amenable gold nanoparticles biofabrication in aged cell culture medium

Green fabrication of nanoscale materials is highly desirable because of associated adverse effects with conventional nanomaterial biomedical applications. Moreover, the higher selective nature of the blood-brain barrier (BBB) limits the brain ailments treatment through conventional chemotherapy, thus providing room for nanotechnology-based modalities for BBB traversing. In this contribution, we have biosynthesized gold nanoparticles from the HAuCl4 solution in the aged cells culture medium. This approach is highly facile without any other chemical utilization. The cell culture medium age and cell number can tune the Au nanoparticles (AuNPs) size from 2 to several hundred nm. The 24 h MTT assay and cell uptake studies in vitro and murine models' vital organs (liver, kidney, spleen, lung, and heart) study up to 48 h demonstrated that biosynthesized AuNPs were biocompatible and BBB amenable. Interestingly, the transferrin and cell culture medium isolated proteins were found factors responsible for HAuCl4 solution biomineralization and size control. Moreover, the protein corona on biosynthesized AuNPs could help them traverse BBB both in vitro and in vivo, suggesting their potential applications for brain disease theranostics. In conclusion, the biosynthesis of AuNPs from aged cells medium is highly facile, green, and biocompatible for brain disease theranostics.

Effect of Mesenchymal Stem Cells and Platelet-Rich Plasma on the Bone Healing of Ovariectomized Rats

We evaluated the efficacy of platelet-rich plasma (PRP) in combination with allogeneic bone marrow mesenchymal stem cells (BMSCs) for the treatment of osteoporotic bone defects in an ovariectomized rat model. By day 42 after injury, in vivo microcomputed tomography (micro-CT) imaging revealed that bone defects of control rats and ovariectomized rats treated with PRP and BMSCs were completely repaired, whereas those of ovariectomized rats treated with PRP or BMSCs alone exhibited slower healing. Histological data were consistent with these results. We also assessed changes to bone trabeculae in the proximal tibial growth plate. In ovariectomized rats treated with PRP or with a combination of PRP and BMSCs, the trabecular connectivity densities (Conn.D), bone volume ratios (BV/TV), and numbers (Tb.N) in the defect areas increased significantly from day 7 to day 42. These results indicate that PRP treatment enhances bone microarchitecture in osteoporosis. Moreover, expression levels of osteogenesis-specific marker genes including RUNX2, OSX, and OPN were significantly upregulated in rats treated with PRP and BMSCs compared to those of other groups. Thus, we conclude that treatment with PRP combined with BMSCs significantly promotes healing of osteoporotic bone defects. This study provides an alternative strategy for the treatment of osteoporotic bone loss.

Effects of TGF-β1 and alginate on the differentiation of rabbit bone marrow-derived mesenchymal stem cells into a chondrocyte cell lineage

The aim of the present study was to investigate the effect of a three-dimensional (3D) culture system of sodium alginate gel on the directional differentiation induction of bone marrow-derived mesenchymal stem cells (BMSCs) into chondrocytes, as well as the in vitro gene transfection technique. The biological characteristics of the passage and proliferation of rabbit BMSCs were investigated under conditions of in vitro monolayer and 3D culture of sodium alginate gel. Transforming growth factor (TGF)-β1 gene recombinant adenoviral cosmid vectors and the recombinant adenoviral vector Ad.TGF-β1 were constructed, and the effect of Ad.TGF-β1 transfection on the differentiation of BMSCs into chondrocytes was investigated. The whole bone marrow rinsing method was used to obtain, separate and purify the rabbit BMSCs, and the in vitro monolayer and 3D culture of sodium alginate gel were thus successfully and stably established. A safe, stable and efficient method of constructing Ad.TGF-β1 TGF-β1 gene recombinant adenoviral vectors was established. Following TGF-β1 transfection, BMSCs were able to continuously secrete significantly increased amounts of specific extracellular matrix components of chondrocytes, such as collagen II and proteoglycans. Furthermore, the effects in the post-gene transfection 3D culture group were found to be enhanced compared with those in the monolayer culture group. In conclusion, the 3D culture system of sodium alginate gel and in vitro gene transfection exhibited significant inductive effects on differentiation, which could be used to promote BMSCs to differentiate into chondrocytes.

The role and mechanism of exogenous calcitonin gene-related peptide on mesenchymal stem cell proliferation and osteogenetic formation

The aims of this study were to expose the function of calcitonin gene-related peptide (CGRP) in the proliferation and intracellular communication of mesenchymal stem cells (MSCs), to observe the change in IGF-1, BMP-2 and their receptor in the MSCs cell with exogenous CGRP, and to explore whether exogenous CGRP will induce MSCs to express the osteoinduced factor and it's receptor. MSCs were separated from bone marrow and collected by gradient centrifugation and adherent culture. Real-time polymerase chain reaction (RT-PCR) was used to detect CGRP receptor in MSCs in logarithmic growth phase [1]. Hybridoma technique was used to produce rabbit-anti-human CGRP receptor, which was used in the Western blot test to detect CGRP receptor protein produced in human MSCs. Then, MSCs were parted into 3 groups decided by the concentration of CGRP. Cell proliferation was detected through methylthiazol tetrazolium (MTT) test. Cell form in each group was detected through optical microscope, in the same time point. Cell cycle was detected with flow cytometric to analyze the ratio of cell in the mitotic time. MSCs collected from healthy volunteer were parted into 3 groups: the control group, the anagen group, and the experimental group. Intracellular communication medium molecule was detected through radioimmunoassay; intracellular communication and signal conduction were detected through carboxyfluorescein diacetate fluorescent dye. The expression of Cx43mRNA was detected through real-time PCR. The mRNA expressions of proliferation-related biological factor of MSCs were detected through real-time PCR. MSCs collected by gradient centrifugation and cultured by adherent culture have high purity and proliferation effect. It was proved through RT-PCR that MSCs express CGRP receptor mRNA, and it was also be proved through Western blot that MSCs express CGRP receptor protein. The MTT test showed similar result, the 10-8 mol/L CGRP group had the highest proliferation speed, and the control group had the lowest. There is statistical difference between experimental group and control group. There also had static difference between the 10-8 mol/L CGRP group and the other two experimental group. Expression of Cx43mRNA in experimental group was higher than the other two groups, but, without static difference. It was proved that the mRNA expressions of IGF-1, IGF-1 receptor, and BMP-2 receptor in experimental group were higher than that in control group with static difference. The mRNA expressions of BMP-2 in all the groups had no static difference. And Ct index in all the groups were higher than 35. It was proved that MSCs express CGRP receptor mRNA and protein. With MTT test, it had been proved that exogenous CGRP can accelerate the proliferation speed in the logarithmic growth phase. With flow cytometric, it had been proved that exogenous CGRP can raise the ratio of the cell in the DNA synthesis period and mitosis prophase. CGRP can promote not only intracellular communication of MSCs but also the expression of Cx43mRNA. The exogenous CGRP can increase the mRNA expression of IGF-1, IGF-1 receptor, and BMP-2 receptor of MSCs. In all the groups, the Ct indexes of BMP-2mRNA were higher than 35, which could be considered as negative expression.

Cultivation and identification of rat bone marrow-derived mesenchymal stem cells

Bone marrow‑derived mesenchymal stem cells (BMSCs) have the potential to form a variety of mesenchymal tissue types, which are a source of cells for bone tissue engineering applications. The present study attempted to establish an effective and convenient method for culturing BMSCs. Total bone marrow cells, which were harvested from rat femurs, were cultured and BMSCs were selected and expanded through passaging in vitro. Furthermore, the biological properties of BMSCs were investigated, specific surface antigen expression was assessed using flow cytometry and the multipotent differentiation potential characteristics were demonstrated using standard in vitro conditions. Monoptychial heterogeneous cells were obtained. A total of 98.4% of cells at passage 3 expressed cluster of differentiation (CD)29 and CD90, but not CD45. The cells were able to differentiate into osteogenic and adipogenic cells. In conclusion, BMSCs that are isolated from the rat bone marrow and exhibit the identified characteristics may be used as seed cells in bone tissue engineering.

Exogenous IL-4-expressing bone marrow mesenchymal stem cells for the treatment of autoimmune sensorineural hearing loss in a guinea pig model

Bone marrow mesenchymal stem cells (BMSCs) expressing recombinant IL-4 have the potential to remediate inflammatory diseases. We thus investigated whether BMSCs expressing exogenous IL-4 could alleviate autoimmune sensorineural hearing loss. BMSCs isolated from guinea pigs were transfected with recombinant lentivirus expressing IL-4. A total of 33 animals were divided into three groups. Group A received scala tympani injection of IL-4-expressing BMSCs, and Group B received control vector-expressing BMSCs, and Group C received phosphate-buffered saline. The distribution of implanted BMSCs in the inner ears was assessed by immunohistochemistry and fluorescence microscopy. Auditory brain-stem response (ABR) was monitored to evaluate the auditory changes. Following BMSCs transplantation, the threshold levels of ABR wave III decreased in Groups A and B and significant differences were observed between these two groups (P < 0.05). Transplanted BMSCs distributed in the scala tympani and scala vestibuli. In some ears with hearing loss, there was a decrease in the number of spiral ganglion cells and varying degrees of endolymphatic hydrops or floccule. Following transplantation, the lentivirus-infected BMSCs migrated to the inner ear and produced IL-4. Our results demonstrate that, upon transplantation, BMSCs and BMSCs expressing recombinant IL-4 have the ability to remediate the inflammatory injury in autoimmune inner ear diseases.

Autologous biological pacing function with adrenergic-responsiveness in porcine of complete heart block

AIMS

To assess the efficacy of autologous biological pacing function by autograft of gene-transferred mesenchymal stem cells in a porcine model of complete heart block.

METHODS AND RESULTS

Fourteen healthy young male pigs were randomized into active group (n=8) and control group (n=6). Porcine MSCs were transfected with Ad.HCN4 or Ad.Null. The pacemaker function of transfected MSCs was studied by whole-cell patch clamp. The CHB model of porcine was created with transthoracic ablation technique and the transfected MSCs were autografted into the free wall of right ventricle. The pacing function was studied by ECG and ambulatory Holter recording weekly. The adrenergic responsiveness was evaluated by the variation of heart rate after isoprenaline infusion or food provision following an overnight fasting. HCN4-MSCs expressed a robust time-dependent inward current (If) and the current density of If was 4.3±0.6 pA/pF at -105 mV. In week 2 after autograft, the heart rate of active group became significantly higher than control (53±5 bpm vs. 38±4 bpm, P<0.05) and the percent of pacing beats in active group was higher than control (69±10% vs. 28±8%, P<0.05). By infusion of isoprenaline, the heart rate was increased significantly in both groups. However, there was a significant increase of heart rate when presenting food for active group (P<0.05) while not in control.

CONCLUSIONS

Our findings demonstrated that autografted HCN4-MSCs could increase the heart rate by providing an adrenergic-responsive biological pacing function, indicating a promising approach without immunological or ethical issues for the treatment of complete heart block.

Restored perfusion and reduced inflammation in the infarcted heart after grafting stem cells with a hyaluronan-based scaffold

The aim of this study is to investigate the blood perfusion and the inflammatory response of the myocardial infarct area after transplanting a hyaluronan-based scaffold (HYAFF(®) 11) with bone marrow mesenchymal stem cells (MSCs). Nine-week-old female pigs were subjected to a permanent left anterior descending coronary artery ligation for 4 weeks. According to the kind of the graft, the swine subjected to myocardial infarction were divided into the HYAFF(®) 11, MSCs, HYAFF(®) 11/MSCs and untreated groups. The animals were killed 8 weeks after coronary ligation. Scar perfusion, evaluated by Contrast Enhanced Ultrasound echography, was doubled in the HYAFF(®) 11/MSCs group and was comparable with the perfusion of the healthy, non-infarcted hearts. The inflammation score of the MSCs and HYAFF(®) 11/MSCs groups was near null, revealing the role of the grafted MSCs in attenuating the cell infiltration, but not the foreign reaction strictly localized around the fibres of the scaffold. Apart from the inflammatory response, the native tissue positively interacted with the HYAFF(®) 11/MSCs construct modifying the extracellular matrix with a reduced presence of collagene and increased amount of proteoglycans. The border-zone cardiomyocytes also reacted favourably to the graft as a lower degree of cellular damage was found. This study demonstrates that the transplantation in the myocardial infarct area of autologous MSCs supported by a hyaluronan-based scaffold restores blood perfusion and almost completely abolishes the inflammatory process following an infarction. These beneficial effects are superior to those obtained after grafting only the scaffold or MSCs, suggesting that a synergic action was achieved using the cell-integrated polymer construct.

Biological basis of bone formation, remodeling, and repair-part I: biochemical signaling molecules

The bony biochemical environment is an active and dynamic system that permits and promotes cellular functions that lead to matrix production and ossification. Each component is capable of conveying important regulatory cues to nearby cells, thus effecting gene expression and changes at the cytostructural level. Here, we review the various signaling molecules that contribute to the active and dynamic nature of the biochemical system. These components include hormones, cytokines, and growth factors. We describe their role in regulating bone metabolism. Certain growth factors (i.e., TGF-beta, IGF-1, and VEGF) are described in greater detail because of their potential importance in developing successful tissue-engineering strategies.

Role of adult mesenchymal stem cells in bone tissue engineering applications: current status and future prospects

Mesenchymal stem cells (MSCs) have been demonstrated as an attractive cell source for tissue-engineering applications because of their ability to be easily isolated and expanded from adult bone marrow aspirates and their versatility for pluripotent differentiation into mesenchymal tissues. This review highlights advances and progress in bone reconstruction techniques for both the repair of site-specific bone defects and the attenuation of musculoskeletal disease symptoms associated with osteoporosis and osteogenesis imperfecta. Despite the enormous potential benefits of MSCs within these approaches, conventional tissue culture methods limit the clinical utility of these cells because of the gradual loss of both their proliferative and differentiation potential during ex vivo expansion. Novel strategies to overcome these limitations are discussed including cultivation in the presence of basic fibroblastic growth factor 2, induction of ectopotic telomerase expression, and ex vivo expansion on various collagenous biomaterials. In addition, this review also outlines mechanistic theories on the potential role of MSC-extracellular matrix interactions in mediating the retention of MSC proliferative and differentiation capacity after ex vivo expansion on collagenous biomaterials.

Osteogenesis of large segmental radius defects enhanced by basic fibroblast growth factor activated bone marrow stromal cells grown on non-woven hyaluronic acid-based polymer scaffold

Osteogenesis of large segmental radius defects in a rat model was studied by implanting a biodegradable non-woven hyaluronic acid-based polymer scaffold (Hyaff 11) alone or in combination with bone marrow stromal cells (BMSCs). These cells had been previously grown in vitro in mineralising medium either supplemented with basic fibroblast growth factor (bFGF) or unsupplemented. The healing of bone defects was evaluated at 40, 80, 160 and 200 days and the repair process investigated by radiographic, histomorphometric (assessment of new bone growth and lamellar bone) and histological analyses (toluidine blue and von Kossa staining). Mineralisation of bone defects occurred in the presence of the Hyaff 11 scaffold alone or when combined with BMSCs grown with or without bFGF, but each process had a different timing. In particular, bFGF significantly induced mineralisation from day 40, whereas 160 days were necessary for direct evidence that a similar process was developing under the other two conditions tested (scaffold alone or with BMSCs). Radiographic score, new bone growth and lamellar bone percentage were highly correlated. The present outcomes were further confirmed by toluidine blue and von Kossa staining. According to these in vivo findings, the Hyaff 11 scaffold is an appropriate carrier vehicle for the repair of bone defects; additionally, it can significantly accelerate bone mineralisation in combination with BMSCs and bFGF.