Tais Hanae Kasai-Brunswick

Migration and homing of bone-marrow mononuclear cells in chronic ischemic stroke after intra-arterial injection

Cell-based treatments have been considered a promising therapy for neurological diseases. However, currently there are no clinically available methods to monitor whether the transplanted cells reach and remain in the brain. In this study we investigated the feasibility of detecting the distribution and homing of autologous bone-marrow mononuclear cells (BMMCs) labeled with Technetium-99 m ((99m)Tc) in a cell-based therapy clinical study for chronic ischemic stroke. Six male patients (ages 24-65 years) with ischemic cerebral infarcts within the middle cerebral artery (MCA) between 59 and 82 days were included. Cell dose ranged from 1.25x10(8) to 5x10(8). Approximately 2x10(7) cells were labeled with (99m)Tc and intra-arterially delivered together with the unlabeled cells via a catheter navigated to the MCA. None of the patients showed any complications on the 120-day follow-up. Whole body scintigraphies indicated cell homing in the brain of all patients at 2 h, while the remaining uptake was mainly distributed to liver, lungs, spleen, kidneys and bladder. Moreover, quantification of uptake in Single-Photon Emission Computed Tomography (SPECT) at 2 h showed preferential accumulation of radioactivity in the hemisphere affected by the ischemic infarct in all patients. However, at 24 h homing could only distinguished in the brains of 2 patients, while in all patients uptake was still seen in the other organs. Taken together, these results indicate that labeling of BMMCs with (99m)Tc is a safe and feasible technique that allows monitoring the migration and engraftment of intra-arterially transplanted cells for at least 24 h.

Safety of autologous bone marrow mononuclear cell transplantation in patients with nonacute ischemic stroke

AIMS To assess the safety and feasibility of intra-arterial transplantation of autologous bone marrow mononuclear cells in patients with middle cerebral artery ischemic stroke within 90 days of symptom onset. PATIENTS & METHODS Six patients were included in the study, and they received 1-5 × 10(8) bone marrow mononuclear cell and were evaluated using blood tests, neurological and imaging examination before treatment, and 1, 3, 7, 30, 60, 90, 120 and 180 days after transplantation. Scintigraphies were carried out 2 and 24 h after the procedure to analyze the biodistribution of labeled cells. Electroencephalogram was conducted within 7 days after transplantation. RESULTS No patients exhibited any complication or adverse events during the procedure. There was no worsening in the neurological scales until the end of the follow-up. CONCLUSION Intra-arterial bone marrow mononuclear cell transplantation is feasible and safe in patients with nonacute ischemic strokes of the middle cerebral artery. Further studies are required to evaluate the efficacy of this therapy.

Biodistribution of bone marrow mononuclear cells after intra-arterial or intravenous transplantation in subacute stroke patients

AIMS To assess the biodistribution of bone marrow mononuclear cells (BMMNC) delivered by different routes in patients with subacute middle cerebral artery ischemic stroke. PATIENTS & METHODS This was a nonrandomized, open-label Phase I clinical trial. After bone marrow harvesting, BMMNCs were labeled with technetium-99m and intra-arterially or intravenously delivered together with the unlabeled cells. Scintigraphies were carried out at 2 and 24 h after cell transplantation. Clinical follow-up was continued for 6 months. RESULTS Twelve patients were included, between 19 and 89 days after stroke, and received 1-5 × 10(8) BMMNCs. The intra-arterial group had greater radioactive counts in the liver and spleen and lower counts in the lungs at 2 and 24 h, while in the brain they were low and similar for both routes. CONCLUSION BMMNC labeling with technetium-99m allowed imaging for up to 24 h after intra-arterial or intravenous injection in stroke patients.

Bone marrow mononuclear cell therapy for patients with cirrhosis: a Phase 1 study

Background: Bone marrow‐derived cell therapy has been investigated in patients with severe liver disease.

Adipose-Derived Stem-Cell Treatment of Skeletal Muscle Injury

BACKGROUND The aim of the present study was to investigate whether adipose-derived stem cells could contribute to skeletal muscle-healing. METHODS Adipose-derived stem cells of male rats were cultured and injected into the soleus muscles of female rats. Two and four weeks after injections, muscles were tested for tetanic force (50 Hz). Histological analysis was performed to evaluate muscle collagen deposition and the number of centronucleated muscle fibers. In order to track donor cells, chimerism was detected with use of real-time polymerase chain reaction targeting the male sex-determining region Y (SRY) gene. RESULTS Two weeks after cell injection, tetanus strength and the number of centronucleated regenerating myofibers, as well as the number of centronucleated regenerating myofibers, were higher in the treated group than they were in the control group (mean and standard error of the mean, 79.2 ± 5.0% versus 58.3 ± 8.1%, respectively [p < 0.05]; and 145 ± 36 versus 273 ± 18 per 10³ myofibers, respectively [p < 0.05]). However, there were no significant differences at four weeks. Treatment did not decrease collagen deposition. Male gene was not detected in female host tissue at two and four weeks after engraftment by polymerase chain reaction analysis. CONCLUSIONS Adipose-derived stem-cell therapy increased muscle repair and force at two weeks, but not four weeks, after injection, suggesting that adipose-derived stem-cell administration may accelerate muscle repair; however, the rapid disappearance of injected cells suggests a paracrine mechanism of action.

Improvement of cardiac function by placenta-derived mesenchymal stem cells does not require permanent engraftment and is independent of the insulin signaling pathway.

IntroductionThe objective of this work was to evaluate the efficacy of placenta-derived mesenchymal stem cell (MSC) therapy in a mouse model of myocardial infarction (MI). Since MSCs can be obtained from two different regions of the human term placenta (chorionic plate or villi), cells obtained from both these regions were compared so that the best candidate for cell therapy could be selected.MethodsFor the in vitro studies, chorionic plate MSCs (cp-MSCs) and chorionic villi MSCs (cv-MSCs) were extensively characterized for their genetic stability, clonogenic and differentiation potential, gene expression, and immunophenotype. For the in vivo studies, C57Bl/6 mice were submitted to MI and, after 21 days, received weekly intramyocardial injections of cp-MSCs for 3 weeks. Cells were also stably transduced with a viral construct expressing luciferase, under the control of the murine stem cell virus (MSCV) promoter, and were used in a bioluminescence assay. The expression of genes associated with the insulin signaling pathway was analyzed in the cardiac tissue from cp-MSCs and placebo groups.ResultsMorphology, differentiation, immunophenotype, and proliferation were quite similar between these cells. However, cp-MSCs had a greater clonogenic potential and higher expression of genes related to cell cycle progression and genome stability. Therefore, we considered that the chorionic plate was preferable to the chorionic villi for the isolation of MSCs. Sixty days after MI, cell-treated mice had a significant increase in ejection fraction and a reduction in end-systolic volume. This improvement was not caused by a reduction in infarct size. In addition, tracking of cp-MSCs transduced with luciferase revealed that cells remained in the heart for 4 days after the first injection but that the survival period was reduced after the second and third injections. Quantitative reverse transcription-polymerase chain reaction revealed similar expression of genes involved in the insulin signaling pathway when comparing cell-treated and placebo groups.ConclusionsImprovement of cardiac function by cp-MSCs did not require permanent engraftment and was not mediated by the insulin signaling pathway.

Adipose-derived stromal cell therapy improves cardiac function after coronary occlusion in rats.

Recent studies have identified adipose tissue as a new source of mesenchymal stem cells for therapy. The purpose of this study was to investigate the therapy with adipose-derived stromal cells (ASCs) in a rat model of healed myocardial infarction (MI). ASCs from inguinal subcutaneous adipose tissue of male Wistar rats were isolated by enzymatic digestion and filtration. Cells were then cultured until passage 3. Four weeks after ligation of the left coronary artery of female rats, a suspension of either 100 μl with phosphate-buffered saline (PBS) + Matrigel + 2 × 106 ASCs labeled with Hoechst (n = 11) or 100 μl of PBS + Matrigel (n = 10) was injected along the borders of the ventricular wall scar tissue. A sham-operated group (n = 5) was submitted to the same surgical procedure except permanent ligation of left coronary artery. Cardiac performance was assessed by electro- and echocardiogram. Echo was performed prior to injections (baseline, BL) and 6 weeks after injections (follow-up, FU), and values after treatment were normalized by values obtained before treatment. Hemodynamic measurements were performed 6 weeks after injections. All infarcted animals exhibited cardiac function impairment. Ejection fraction (EF), shortening fractional area (SFA), and left ventricular akinesia (LVA) were similar between infarcted groups before treatment. Six weeks after therapy, ASC group showed significant improvement in all three ECHO indices in comparison to vehicle group. In anesthetized animals dp/dt+ was also significantly higher in ASCs when compared to vehicle. In agreement with functional improvement, scar area was diminished in the ASC group. We conclude that ASCs improve cardiac function in infarcted rats when administered directly to the myocardium.

Sustained IGF-1 secretion by adipose-derived stem cell improves infarcted heart function.

The mechanism by which stem cell-based therapy improves heart function is still unknown, but paracrine mechanisms seem to be involved. Adipose-derived stem cells (ADSCs) secrete several factors, including insulin-like growth factor-1 (IGF-1), which may contribute to myocardial regeneration. Our aim was to investigate whether the overexpression of IGF-1 in ADSCs (IGF-1-ADSCs) improves treatment of chronically infarcted rat hearts. ADSCs were transduced with a lentiviral vector to induce IGF-1 overexpression. IGF-1-ADSCs transcribe100- to 200-fold more IGF-1 mRNA levels compared to nontransduced ADSCs. IGF-1 transduction did not alter ADSC immunophenotypic characteristics even under hypoxic conditions. However, IGF-1-ADSCs proliferate at higher rates and release greater amounts of growth factors such as IGF-1, vascular endothelial growth factor (VEGF), and hepatocyte growth factor (HGF) under normoxic and hypoxic conditions. Importantly, IGF-1 secreted by IGF-1-ADSCs is functional given that Akt-1 phosphorylation was remarkably induced in neonatal cardiomyocytes cocultured with IGF-1-ADSCs, and this increase was prevented with phosphatidylinositol 3-kinase (PI3K) inhibitor treatment. Next, we tested IGF-1-ADSCs in a rat myocardial infarction (MI) model. MI was performed by coronary ligation, and 4 weeks after MI, animals received intramyocardial injections of either ADSCs (n = 7), IGF-1-ADSCs (n = 7), or vehicle (n = 7) into the infarcted border zone. Left ventricular function was evaluated by echocardiography before and after 6 weeks of treatment, and left ventricular hemodynamics were assessed 7 weeks after cell injection. Notably, IGF-1-ADSCs improved left ventricular ejection fraction and cardiac contractility index, but did not reduce scar size when compared to the ADSC-treated group. In summary, transplantation of ADSCs transduced with IGF-1 is a superior therapeutic approach to treat MI compared to nontransduced ADSCs, suggesting that gene and cell therapy may bring additional benefits to the treatment of MI.

Reprogramming to a pluripotent state modifies mesenchymal stem cell resistance to oxidative stress.

Properties of induced pluripotent stem cells (iPSC) have been extensively studied since their first derivation in 2006. However, the modification in reactive oxygen species (ROS) production and detoxification caused by reprogramming still needs to be further elucidated. The objective of this study was to compare the response of iPSC generated from menstrual blood–derived mesenchymal stem cells (mb‐iPSC), embryonic stem cells (H9) and adult menstrual blood–derived mesenchymal stem cells (mbMSC) to ROS exposure and investigate the effects of reprogramming on cellular oxidative stress (OS). mbMSC were extremely resistant to ROS exposure, however, mb‐iPSC were 10‐fold less resistant to H2O2, which was very similar to embryonic stem cell sensitivity. Extracellular production of ROS was also similar in mb‐iPSC and H9 and almost threefold lower than in mbMSC. Furthermore, intracellular amounts of ROS were higher in mb‐iPSC and H9 when compared with mbMSC. As the ability to metabolize ROS is related to antioxidant enzymes, we analysed enzyme activities in these cell types. Catalase and superoxide dismutase activities were reduced in mb‐iPSC and H9 when compared with mbMSC. Finally, cell adhesion under OS conditions was impaired in mb‐iPSC when compared with mbMSC, albeit similar to H9. Thus, reprogramming leads to profound modifications in extracellular ROS production accompanied by loss of the ability to handle OS.

Mesenchymal stem cells and cell-derived extracellular vesicles protect hippocampal neurons from oxidative stress and synapse damage induced by amyloid-β oligomers

Alzheimers disease (AD) is a disabling and highly prevalent neurodegenerative condition, for which there are no effective therapies. Soluble oligomers of the amyloid-β peptide (AβOs) are thought to be proximal neurotoxins involved in early neuronal oxidative stress and synapse damage, ultimately leading to neurodegeneration and memory impairment in AD. The aim of the current study was to evaluate the neuroprotective potential of mesenchymal stem cells (MSCs) against the deleterious impact of AβOs on hippocampal neurons. To this end, we established transwell cocultures of rat hippocampal neurons and MSCs. We show that MSCs and MSC-derived extracellular vesicles protect neurons against AβO-induced oxidative stress and synapse damage, revealed by loss of pre- and postsynaptic markers. Protection by MSCs entails three complementary mechanisms: 1) internalization and degradation of AβOs; 2) release of extracellular vesicles containing active catalase; and 3) selective secretion of interleukin-6, interleukin-10, and vascular endothelial growth factor to the medium. Results support the notion that MSCs may represent a promising alternative for cell-based therapies in AD.