Mouse Adipose-derived Mesenchymal Stem Cells Research Articles

A Comparison of Proteins Expressed between Human and Mouse Adipose-Derived Mesenchymal Stem Cells by a Proteome Analysis through Liquid Chromatography with Tandem Mass Spectrometry.

Adipose-derived mesenchymal stem cells (ADSCs) have become a common cell source for cell transplantation therapy. Clinical studies have used ADSCs to develop treatments for tissue fibrosis, such as liver cirrhosis and pulmonary fibroma. The need to examine and compare basic research data using clinical research data derived from mice and humans is expected to increase in the future. Here, to better characterize the cells, the protein components expressed by human ADSCs used for treatment, and mouse ADSCs used for research, were comprehensively analyzed by liquid chromatography with tandem mass spectrometry. We found that 92% (401 type proteins) of the proteins expressed by ADSCs in humans and mice were consistent. When classified by the protein functions in a gene ontology analysis, the items that differed by >5% between human and mouse ADSCs were “biological adhesion, locomotion” in biological processes, “plasma membrane” in cellular components, and “antioxidant activity, molecular transducer activity” in molecular functions. Most of the listed proteins were sensitive to cell isolation processes. These results show that the proteins expressed by human and murine ADSCs showed a high degree of correlation.

Effect of miR-26a-5p on the Wnt/Ca(2+) Pathway and Osteogenic Differentiation of Mouse Adipose-Derived Mesenchymal Stem Cells.

Elucidation of the molecular mechanisms that regulate the differentiation of adipose-derived mesenchymal stem cells into osteogenic cells may lead to new methods for bone tissue engineering. We examined the role of miR-26a-5p in the regulation of osteogenic differentiation of mouse adipose-derived mesenchymal stem cells (mADSCs) by using mimics and inhibitors of this microRNA. Our results showed that over-expression of miR-26a-5p inhibited osteogenesis and that suppression of endogenous miR-26a-5p promoted osteogenesis. Four bioinformatics algorithms indicated that the 3'UTR of Wnt5a was a potential target of miR-26a-5p. We confirmed this prediction by use of dual-luciferase reporter assay and GFP/RFP assay. We also examined the molecular mechanisms by which miR-26a-5p regulates osteogenesis. Fura-2AM and Western blot assays after transfection indicated that miR-26a-5p repressed WNT5A, inhibited calcium flux and protein kinase C, and suppressed osteogenic differentiation of mADSCs. By contrast, miR-26a-5p inhibition activated these signal proteins and promoted osteogenic differentiation. Taken together, our results suggest that up-regulation of miR-26a-5p inhibits osteogenic differentiation of mADSCs by directly targeting the 3'UTR of Wnt5a, thereby down-regulating the Wnt/Ca(2+) signaling pathway.

Effect of adipose-derived mesenchymal stem cells (ADSC) on the T cell immune status of allergic rhinitis mouse model

To investigate the regulation of adipose-derived mesenchymal stem cells (ADSC) on helper T cells and regulatory T cells in allergic rhinitis(AR) mouse model and the underlying mechanisms. Using random number table, 60 Balb/c mice were divided into 6 groups (represented by: sensitized/challenged/treated ), they were the experimental group 1(OVA/OVA/high dose ADSC), the experimental group 2(OVA/OVA/low dose ADSC), the experimental group 3(OVA/OVA/PBS), the experimental group 4(OVA/OVA/0), the control group 1(PBS/PBS/0) and the control group 2(0/0/0). The mouse ADSC were isolated and cultured through conventional method, and AR mouse model was built with OVA and aluminum. The mice were injected with high (3×10(6)), low (1×10(6)) ADSC respectively labeled by CM-Dil for 3 consecutive days via tail-vein injection and sacrificed 48 hours later. Finally, levels of IL-4, IL-6, IL-10 and IFN -γ in serum were examined by ELISA; expressions of the four cytokines in spleen were examined by q RT-PCR; migration of ADSC to mouse model nasal mucosa were observed through fluorescence microscope; eosinophil infiltration were observed by the nasal HE staining. Mouse ADSC was isolated, cultured and identified successfully. There was significant difference in symptom scores of AR models (compared with 0/0/0 group, P<0.01). The IL-4 and IL-6 levels of OVA/OVA/high ADSC group were significantly lower than OVA/OVA/0 group (group 1: (17.95±7.78), (27.51±5.93) pg/ml; group 4: (56.82±9.12), (70.03±7.22) pg/ml), the IFN-γ and IL-10 levels increased significantly (group 1: (367.74±13.79), (417.10±72.40) pg/ml; group 4: (199.46±11.25), (122.50±15.57) pg/ml) in serum. These differences were statistically significant(P<0.01). Compared with OVA/OVA/low ADSC group, the IL-4 and IL-6 levels decreased significantly (group 1: (17.95±7.78), (27.51±5.93) pg/ml; group 2: (41.57±12.27), (56.21±9.23)pg/ml) of OVA / OVA / high ADSC group, and the IFN-γ and IL-10 increased significantly (group 1: (367.74±13.79), (417.10±72.40)pg/ml; group 2: (281.77±30.41), (203.45±87.10) pg/ml). These differences were statistically significant(P<0.01). At the same time, the corresponding changes observed at the levels of the cytokines' mRNA. ADSC labeled by CM-Dil could migrate to the mouse nasal mucosa. OVA/OVA/high ADSC group showed the more red fluorescence than the OVA/OVA/low ADSC group. The eosinophils in nasal mucosa of the two groups reduced compared with the normal control. ADSC injected via tail-vein can migrate to nasal mucosa and play non-specific immune effects, that may to effect the releases of some cytokines then to regulate the Th1/Th2 imbalance and the function of Treg cell, finally that be dose-related in a certain extent.

Reprogramming Adipose Tissue-Derived Mesenchymal Stem Cells into Pluripotent Stem Cells by a Mutant Adeno-Associated Viral Vector

Induced pluripotent stem (iPS) cells have great potential for personalized regenerative medicine. Although several different methods for generating iPS cells have been reported, improvement of safety and efficiency is imperative. In this study, we tested the feasibility of using a triple tyrosine mutant AAV2 (Y444+500+730F) vector, designated AAV2.3m, to generate iPS cells. We developed a polycistronic rAAV2.3m vector expressing three reprogramming factors, Klf4, Oct4, and Sox2, and then used this vector to infect mouse adipose-derived mesenchymal stem cells (AT-MSCs) to induce the generation of iPS cells. We demonstrated that (1) the triple tyrosine mutant AAV2 vector is able to reprogram mouse adult adipose tissue-derived stem cells into the pluripotent state. Those rAAV2.3m-derived iPS (rAAV2.3m-iPS) cells express endogenous pluripotency-associated genes including Oct4, Sox2, and SSEA-1, and form teratomas containing multiple tissues in vivo; (2) c-myc, an oncogene, is dispensable in rAAV2.3m-mediated cellular reprogramming; and (3) transgene expression is undetectable after reprogramming, whereas vector DNA is detectable, indicating that transgenes are silenced. These results indicated the rAAV vector may have some advantages in generating iPS cells.

Spatial Vascular Volume Fraction Imaging for Quantitative Assessment of Angiogenesis

The purpose of this study is to set up a quantitative imaging strategy for therapeutic angiogenesis and monitoring the spatial distribution and survival of the transplanted mesenchymal stem cells (MSCs) in vivo simultaneously. Mouse adipose-derived MSCs (AD-MSCs) were isolated from firefly luciferase and enhanced green fluorescent protein positive transgenic mice, and implanted intramuscularly into hindlimbs of C57BL/6 mice. Serial spatial vascular volume fraction (SVVF) imaging was performed to quantitatively assess angiogenesis by calculating the spatially explicit vascular volume. The hybrid microcomputed tomography angiography/bioluminescence tomography (micro-CTA/BLT) was used to track the fate of AD-MSCs in vivo. Laser Doppler perfusion imaging (LDPI) was used to evaluate blood perfusion. Ex vivo conventional methods were performed to cross-validate the therapeutic angiogenesis. There was a linear correlation relation between the cell number and Fluc/Fluc protein signal intensity in AD-MSCs via BLT. LDPI showed improved perfusion rate in mice treated with cytotherapy, compared to control mice. Furthermore, angiogenesis assessed by SVVF was 10.67 ± 0.41 %, 13.99 ± 0.28 %, and 23.50 ± 1.23 % on days 7, 14, and 28 post-transplantation of AD-MSCs, respectively. Vascular densities of the longitudinally monitored ischemic hindlimbs were significantly higher than those at early time points and controls, which was also confirmed by vascular corrosion casting, scanning electron microscopic imaging, and histological analysis. Hybrid high-resolution micro-CTA/BLT enabled monitoring and quantitative assessment of cytotherapeutically induced angiogenesis in vivo.

Tissue factor triggers procoagulation in transplanted mesenchymal stem cells leading to thromboembolism

Mesenchymal stem cells (MSCs) have shown extreme clinical promise as a therapeutic regenerative system in the treatment of numerous types of diseases. A recent report, however, documented lethal pulmonary thromboembolism in a patient following the administration of adipose-derived MSCs (ADSCs). In our study, we designed experiments to examine the role of tissue factor (TF), which is highly expressed at the level of mRNA and localized to the cell surface of cultured MSCs, as a triggering factor in the procoagulative cascade activated by infused MSCs. A high mortality rate of ∼85% in mice was documented following intravenous infusion of mouse ADSCs within 24h due to the observation of pulmonary embolism. Rotation thromboelastometry and plasma clotting assay demonstrated significant procoagulation by the cultured mouse ADSCs, and preconditioning of ADSCs with an anti-TF antibody or usage of factor VII deficient plasma in the assay successfully suppressed the procoagulant properties. These properties were also observed in human ADSCs, and could be suppressed by recombinant human thrombomodulin. In uncultured mouse adipose-derived cells (ADCs), the TF-triggered procoagulant activity was not observed and all mice infused with these uncultured ADCs survived after 24h. This clearly demonstrated that the process of culturing cells plays a critical role in sensitizing these cells as a procoagulator through the induction of TF expression. Our results would recommend that clinical applications of MSCs to inhibit TF activity using anti-coagulant agents or genetic approaches to maximize clinical benefit to the patients.

In Vitro Neuronal Induction of Adipose-Derived Stem Cells and their Fate after Transplantation into Injured Mouse Brain

The effect of substances known as inducers of neuronal differentiation on cultured human and mouse adipose-derived mesenchymal stem cells (ASCs) and their fate after transplantation into the injured and ischemic mouse brains were studied. ASCs were isolated from the human and mouse adipose tissue. Inducers of neuronal differentiation included β-mercaptoethanol, glial cell line-derived neurotrophic factor (GNDF), brain-derived neurotrophic factor (BDNF), retinoic acid (RA), 5-azacytidine, as well as their combinations. Three days after the induction, the phenotype of the induced cells was analyzed using immunocytochemistry and real-time PCR assay for differential expression of specific genes. The induction efficiency was evaluated by the increased transcription of neuronal differentiation markers: nestin, β-III-tubulin (Tub-B), microtubule-associated protein 2 (MAP2), and neuron-specific enolase (ENO2). The expression of marker genes was tested by immunocytochemical analysis. ASC cultivation in the medium with RA or BDNF in combination with 5- azacytidine for a week increased the mRNA and protein levels of nestin, Tub-B, and ENO2. The transplantation of induced mouse ASCs into the mouse brain increased the lifespan of the cells relative to control uninduced cells and promoted their migration from the transplantation site to the recipient cerebral parenchyma. The transplantation of the induced cells into the mouse brain pre-exposed to endothelin- 1 promoted a more active cell migration into the surrounding ischemic brain tissue. Thus, ASC exposure to RA or BDNF in combination with 5-azacytidine elevated the transcription of the neuronal differentiation markers and improved the viability and integration of ASCs grafted into the mouse brain.