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Although limited spontaneous recovery occurs after spinal cord injury (SCI), current knowledge reveals that multiple forms of axon growth in spared axons can lead to circuit reorganization and a detour or relay pathways. This hypothesis has been derived mainly from studies of the corticospinal tract (CST), which is the primary descending motor pathway in mammals. The major CST is the dorsal CST (dCST), being the major projection from cortex to spinal cord. Two other components often called "minor" pathways are the ventral and the dorsal lateral CSTs, which may play an important role in spontaneous recovery. Intravenous infusion of mesenchymal stem cells (MSCs) provides functional improvement after SCI with an enhancement of axonal sprouting of CSTs. Detailed morphological changes of CST pathways, however, have not been fully elucidated. The primary objective was to evaluate detailed changes in descending CST projections in SCI after MSC infusion. The MSCs were infused intravenously one day after SCI. A combination of adeno-associated viral vector (AAV), which is an anterograde and non-transsynaptic axonal tracer, was injected 14 days after SCI induction. The AAV with advanced tissue clearing techniques were used to visualize the distribution pattern and high-resolution features of the individual axons coursing from above to below the lesion. The results demonstrated increased observable axonal connections between the dCST and axons in the lateral funiculus, both rostral and caudal to the lesion core, and an increase in observable axons in the dCST below the lesion. This increased axonal network could contribute to functional recovery by providing greater input to the spinal cord below the lesion.

SUMMARYSchwann cells (SCs) are the myelinating and non-myelinating glia of the peripheral nervous system (PNS) and are essential for its function. Defects in SCs are associated with many PNS disorders including diabetic peripheral neuropathy (DPN), a condition affecting millions of patients. Here we present a strategy for deriving and purifying SCs from human pluripotent stem cells (hPSCs). The scalable cultures of SCs allow basic and translational applications such as high-resolution molecular and functional characterization, developmental studies, modeling and mechanistic understanding of SC diseases and drug discovery. Our hPSC-derived SCs recapitulate the key molecular features of primary SCs and are capable of engrafting efficiently and producing myelin in injured sciatic nerves in rats. We further established an hPSC-based in vitro model of DPN that revealed the selective vulnerability of human SCs to hyperglycemia-induced cytotoxicity. We established a high-throughput screening system that identified a candidate drug that counteracts glucose-mediated cytotoxicity in SCs and normalizes glucose-induced transcriptional and metabolic abnormalities in SCs. Treatment of hyperglycemic mice with this drug candidate rescues sensory function, prevents SC death, and counteracts myelin damage in sciatic nerves suggesting considerable potential as a novel treatment for DPN.

Animal models are required to study the pathogenesis of brainstem ischemia and to develop new therapeutic approaches to promote functional recovery after ischemia in humans. Few models of brainstem ischemia are available, and they show great variability or cause early lethality. New, reliable animal models are therefore needed. By selectively ligating four points of the lower basilar artery, we developed a new focal basilar artery occlusion model that causes a localized brainstem ischemic lesion in female Sprague-Dawley rats. Analysis of ischemic lesion volume and neurological deficits over a period of 28 d showed that the rats present symptoms specific to this type of stroke while the ischemic lesion remains relatively unchanged over time. This procedure allows higher survival rates and extended observation periods compared with other models of brainstem ischemia. The procedure takes ~40 min, can be performed by researchers with basic surgical skills and does not require specialized surgical equipment. This protocol is highly reliable and will be useful to evaluate new therapeutic approaches to promote functional recovery in patients with brainstem ischemia.

OBJECTIVEIn-stent restenosis after percutaneous transluminal angioplasty and stenting (PTAS) due to neointimal hyperplasia is a potential cause of clinical complications, including repeated revascularization and ischemic events. Neointimal hyperplasia induced by an inflammatory response to the stent strut may be a possible mechanism of in-stent restenosis. Intravenous infusion of bone marrow–derived mesenchymal stem cells (MSCs) has been reported to show therapeutic efficacy for cerebral stroke, presumably by an antiinflammatory effect. This study aimed to determine whether MSCs can reduce or prevent neointimal hyperplasia induced by an endovascular stent.METHODSIn this study, two types of bare metal stents were deployed using a porcine (mini-pig) model. One stent was implanted in the common carotid artery (CCA), which is considered quite similar to the human CCA, and the other was inserted in the superficial cervical artery (SCA), which is similar in size to the human middle cerebral artery. Angiographic images, intravascular ultrasound (IVUS) imaging, and microscopic images were used for analysis.RESULTSAngiographic images and IVUS studies revealed that intravenous infusion of MSCs immediately after deployment of stents prevented in-stent stenosis of the CCA and SCA. Histological analysis also confirmed that inflammatory responses around the stent struts were reduced in both the stented CCA and SCA in the mini-pig.CONCLUSIONSIntravenous infusion of MSCs inhibited the inflammatory reaction to an implanted stent strut, and prevented progressive neointimal hyperplasia in the stented CCA and SCA in a porcine model. Thus, MSC treatment could attenuate the recurrence of cerebral ischemic events after stenting.

BACKGROUND Brain injuries resulting from motor vehicle accidents and falls, as well as hypoxic insults and other conditions, are one of the leading causes of disability and death in the world. Current treatments are limited but include continuous rehabilitation, especially for chronic brain injury. Recent studies have demonstrated that the intravenous infusion of mesenchymal stem cells (MSCs) has therapeutic efficacy for several neurological diseases, including stroke and spinal cord injury. OBJECTIVE The objective of our investigator-initiated clinical trial is to assess the safety and potential efficacy of the intravenous infusion of autoserum-expanded autologous MSCs for patients with chronic brain injury. METHODS The (phase 2) trial will be a single-arm, open-label trial with the primary objective of confirming the safety and efficacy of autoserum-expanded autologous MSCs (STR-01; produced under good manufacturing practices) when administered to patients with chronic brain injury. The estimated number of enrolled participants is 6 to 20 patients with a modified Rankin Scale grade of 3 to 5. The assessment of safety and the proportion of cases in which the modified Rankin Scale grade improves by 1 point or more at 180 days after the injection of STR-01 will be performed after MSC infusion. RESULTS We received approval for our clinical trial from the Japanese Pharmaceuticals and Medical Devices Agency on December 12, 2017. The trial will be completed on June 11, 2023. The registration term is 5 years. The recruitment of the patients for this trial started on April 20, 2018, at Sapporo Medical University Hospital in Japan. CONCLUSIONS Our phase 2 study will aim to address the safety and efficacy of the intravenous infusion of MSCs for patients with chronic brain injury. The use of STR-01 has been performed for patients with cerebral infarction and spinal cord injury, providing encouraging results. The potential therapeutic efficacy of the systemic administration of autoserum-expanded autologous MSCs for chronic brain injury should be evaluated, given its safety and promising results for stroke and spinal cord injury. CLINICALTRIAL Japan Medical Association Center for Clinical Trials JMA-IIA00333; https://tinyurl.com/nzkdfnbc INTERNATIONAL REGISTERED REPORT DERR1-10.2196/37898

After CNS trauma such as spinal cord injury, the ability of surviving neural elements to sprout axons, reorganize neural networks and support recovery of function is severely restricted, contributing to chronic neurological deficits. Among limitations on neural recovery are myelin-associated inhibitors functioning as ligands for neuronal Nogo receptor 1 (NgR1). A soluble decoy (NgR1-Fc, AXER-204) blocks these ligands and provides a means to promote recovery of function in multiple preclinical rodent models of spinal cord injury. However, the safety and efficacy of this reagent in non-human primate spinal cord injury and its toxicological profile have not been described. Here, we provide evidence that chronic intrathecal and intravenous administration of NgR1-Fc to cynomolgus monkey and to rat are without evident toxicity at doses of 20 mg and greater every other day (≥2.0 mg/kg/day), and far greater than the projected human dose. Adult female African green monkeys underwent right C5/6 lateral hemisection with evidence of persistent disuse of the right forelimb during feeding and right hindlimb during locomotion. At 1 month post-injury, the animals were randomized to treatment with vehicle (n = 6) or 0.10–0.17 mg/kg/day of NgR1-Fc (n = 8) delivered via intrathecal lumbar catheter and osmotic minipump for 4 months. One animal was removed from the study because of surgical complications of the catheter, but no treatment-related adverse events were noted in either group. Animal behaviour was evaluated at 6–7 months post-injury, i.e. 1–2 months after treatment cessation. The use of the impaired forelimb during spontaneous feeding and the impaired hindlimb during locomotion were both significantly greater in the treatment group. Tissue collected at 7–12 months post-injury showed no significant differences in lesion size, fibrotic scar, gliosis or neuroinflammation between groups. Serotoninergic raphespinal fibres below the lesion showed no deficit, with equal density on the lesioned and intact side below the level of the injury in both groups. Corticospinal axons traced from biotin-dextran-amine injections in the left motor cortex were equally labelled across groups and reduced caudal to the injury. The NgR1-Fc group tissue exhibited a significant 2–3-fold increased corticospinal axon density in the cervical cord below the level of the injury relative to the vehicle group. The data show that NgR1-Fc does not have preclinical toxicological issues in healthy animals or safety concerns in spinal cord injury animals. Thus, it presents as a potential therapeutic for spinal cord injury with evidence for behavioural improvement and growth of injured pathways in non-human primate spinal cord injury.

Magnetic resonance angiography (MRA) is an important tool in rat models of cerebrovascular disease. Although MRA has long been used in rodents, the image quality is typically not as high as that observed in clinical practice. Moreover, studies on MRA image quality in rats are limited. This study aimed to develop a practical high-spatial-resolution MRA protocol for imaging cerebral arteries in rats.We used the "half position method" regarding coil placement and modified the imaging parameters and image reconstruction method. We applied this new imaging method to measure maturation-related signal changes on rat MRAs.The new practical high-spatial-resolution MRA imaging protocol obtained a signal intensity up to 3.5 times that obtained using a basic coil system, simply by modifying the coil placement method. This method allowed the detection of a gradual decrease in the signal in cerebral vessels with maturation.A high-spatial-resolution MRA for rats was obtained with an imaging time of approximately 100 min. Comparable resolution and image quality were obtained using the new protocol with an imaging time of 30 min CONCLUSIONS: The new practical high-spatial-resolution MRA protocol can be implemented simply and successfully to achieve high image quality with an imaging time of approximately 30 min. This protocol will benefit researchers performing MRA imaging in cerebral artery studies in rats.

INTRODUCTION After traumatic nerve injury, neuromuscular junction remodeling plays a key role in determining functional outcomes. Immunohistochemical analyses of denervated muscle biopsies may provide valuable prognostic data regarding clinical outcomes to supplement electrodiagnostic studies. METHODS We performed biopsies on nonfunctioning deltoid muscles in two patients after gunshot wounds and visualized the neuromuscular junctions using two-photon microscopy with immunohistochemistry. RESULTS Although the nerves in both patients showed evidence of acute Wallerian degeneration, some of the motor endplates were intact but exhibited significantly decreased surface area and volume. Both patients exhibited substantial recovery of motor function over several weeks postinjury. DISCUSSION Two-photon microscopic assessment of neuromuscular junction integrity and motor endplate morphometry in muscle biopsies provided evidence of partial sparing of muscle innervation. This finding supported the clinical judgment that eventual recovery would occur. With further study, this technique may help to guide operative decisionmaking after traumatic nerve injuries.

Background Surgical reconstruction options of soft-tissue defects often include random pattern skin flaps. Flap survival depends on flap size and rotation arc and can be challenging regarding flap perfusion, leading to wound healing complications, insufficient wound coverage, and even flap loss. Therefore, novel approaches that promote skin flap survival are required. Bone marrow-derived mesenchymal stem cells intravenous infusion is therapeutically effective in various experimental disease models by means of multimodal and orchestrated mechanisms including anti-inflammatory and immunomodulatory effects, and by means of microvasculature reestablishment. Methods A modified McFarlane-type rodent skin flap model was used. After skin flap surgery, intravenous infusion of mesenchymal stem cells or vehicle was performed. In vivo optical near-infrared imaging using indocyanine green was performed, followed by histologic analysis, including hematoxylin and eosin and Masson trichrome staining, and gene expression analysis. Results The flap survival area was greater in the mesenchymal stem cell group. In vivo optical near-infrared perfusion imaging analysis suggested that skin blood perfusion was greater in the mesenchymal stem cell group. Ex vivo histologic analysis demonstrated that the skin structure was more clearly observed in the mesenchymal stem cell group. The dermal thickness was greater in the mesenchymal stem cell group, according to the Masson trichrome staining results. The authors observed a higher expression of fibroblast growth factor 2 mRNA in the tissues of the mesenchymal stem cell group using quantitative reverse-transcription polymerase chain reaction. Conclusion These results suggest that intravenous infusion of bone marrow-derived mesenchymal stem cells promotes skin survival of random pattern flaps, which is associated with increased blood perfusion and higher expression of fibroblast growth factor 2.

Intravenous (IV) infusion of bone marrow‐derived mesenchymal stem/stromal cells (MSCs) stabilizes the blood‐spinal cord barrier (BSCB) and improves functional recovery in experimental models of spinal cord injury (SCI). Although IV delivered MSCs do not traffic to the injury site, IV delivered small extracellular vesicles (sEVs) derived from MSCs (MSC‐sEVs) do and are taken up by a subset of M2 macrophages. To test whether sEVs released by MSCs are responsible for the therapeutic effects of MSCs, we tracked sEVs produced by IV delivered DiR‐labelled MSCs (DiR‐MSCs) after transplantation into SCI rats. We found that sEVs were released by MSCs in vivo, trafficked to the injury site, associated specifically with M2 macrophages and co‐localized with exosome markers. Furthermore, while a single MSC injection was sufficient to improve locomotor recovery, fractionated dosing of MSC‐sEVs over 3 days (F‐sEVs) was required to achieve similar therapeutic effects. Infusion of F‐sEVs mimicked the effects of single dose MSC infusion on multiple parameters including: increased expression of M2 macrophage markers, upregulation of transforming growth factor‐beta (TGF‐β), TGF‐β receptors and tight junction proteins, and reduction in BSCB permeability. These data suggest that release of sEVs by MSCs over time induces a cascade of cellular responses leading to improved functional recovery.

Cerebral small vessel disease (CSVD) is not only a cause of vascular dementia (VD) but also a contributing factor to Alzheimer's disease (AD). The essential pathological feature of CSVD is the disruption of blood-brain barrier (BBB). Dysfunction of BBB due to degeneration of both endothelial cells and pericytes in capillaries leads to neuronal damage and progressive brain atrophy. Moreover, deterioration of amyloid-β (Aβ) clearance due to the failure of the transvascular BBB transport system results in accumulation of Aβ in the brain. Intravenous infusion of mesenchymal stem cells (MSCs) elicits functional recovery in experimental models including stroke and spinal cord injury. One effect of MSCs is to restore disrupted BBB through remodeling of microvasculature. Using spontaneously hypertensive rats (stroke-prone) with impaired cognitive function as a CSVD model, we have shown that infused MSCs has a therapeutic effect for cognitive function. Restoration of BBB function via remodeling of microvasculature and inhibition of Aβ accumulation could inhibit progressive brain atrophy and lead to restore cognitive dysfunction. Gene expression analysis indicated that infused MSCs activates both transforming growth factor-β and angiopoietin 1 signaling pathways and promotes the remodeling of microvasculature. Thus, infused MSCs may represent a novel therapy for both VD and AD.

Background Brain injuries resulting from motor vehicle accidents and falls, as well as hypoxic insults and other conditions, are one of the leading causes of disability and death in the world. Current treatments are limited but include continuous rehabilitation, especially for chronic brain injury. Recent studies have demonstrated that the intravenous infusion of mesenchymal stem cells (MSCs) has therapeutic efficacy for several neurological diseases, including stroke and spinal cord injury. Objective The objective of our investigator-initiated clinical trial is to assess the safety and potential efficacy of the intravenous infusion of autoserum-expanded autologous MSCs for patients with chronic brain injury. Methods The (phase 2) trial will be a single-arm, open-label trial with the primary objective of confirming the safety and efficacy of autoserum-expanded autologous MSCs (STR-01; produced under good manufacturing practices) when administered to patients with chronic brain injury. The estimated number of enrolled participants is 6 to 20 patients with a modified Rankin Scale grade of 3 to 5. The assessment of safety and the proportion of cases in which the modified Rankin Scale grade improves by 1 point or more at 180 days after the injection of STR-01 will be performed after MSC infusion. Results We received approval for our clinical trial from the Japanese Pharmaceuticals and Medical Devices Agency on December 12, 2017. The trial will be completed on June 11, 2023. The registration term is 5 years. The recruitment of the patients for this trial started on April 20, 2018, at Sapporo Medical University Hospital in Japan. Conclusions Our phase 2 study will aim to address the safety and efficacy of the intravenous infusion of MSCs for patients with chronic brain injury. The use of STR-01 has been performed for patients with cerebral infarction and spinal cord injury, providing encouraging results. The potential therapeutic efficacy of the systemic administration of autoserum-expanded autologous MSCs for chronic brain injury should be evaluated, given its safety and promising results for stroke and spinal cord injury. Trial Registration Japan Medical Association Center for Clinical Trials JMA-IIA00333; https://tinyurl.com/nzkdfnbc International Registered Report Identifier (IRRID) DERR1-10.2196/37898

Highlights • The HSE-RFP reporter detects primarily- and secondarily-damaged neural cells in spinal cord injury. • The HSE-RFP reporter detects primarily- and secondarily-damaged neural cells in sciatic nerve injury. • Reporter-positive secondarily-injured neurons show altered physiological properties., Spinal cord and peripheral nerve injury results in extensive damage to the locally injured cells as well as distant cells that are functionally connected to them. Both primary and secondary damage can cause a broad range of clinical abnormalities, including neuropathic pain and cognitive and memory dysfunction. However, the mechanisms underlying these abnormalities remain unclear, awaiting new methods to identify affected cells to enable examination of their molecular, cellular and physiological characteristics. Here, we report that both primary and secondary damage to cells in mouse models of spinal cord and peripheral nerve injury can be detected in vivo using a novel fluorescent reporter system based on the immediate stress response via activation of Heat Shock Factor 1. We also provide evidence for altered electrophysiological properties of reporter-positive secondarily-injured neurons. The comprehensive identification of injured, but surviving cells located both close and at distant locations from the injury site in vivo will provide a way to study their pathophysiology and possibly prevention of their further deterioration.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative fatal disorder in which motor neurons within the brain and spinal cord degenerate. A single infusion of mesenchymal stem cells (MSCs) delays disease progression by protecting motor neurons and restoring the blood-spinal cord barrier in the SOD1G93A transgenic ALS rat model. However, the therapeutic effect of a single infusion of MSCs is transient and does not block disease progression. In this study, we demonstrated that repeated administration of MSCs (weekly, four times) increased the survival period, protected motor functions, and reduced deterioration of locomotor activity compared to a single infusion and vehicle infusion, after which rats displayed progressive deterioration of hind limb function. We also compared the days until gait ability was lost in rats and found that the repeated-infused group maintained gait ability compared to the single-infusion and vehicle-infusion groups. These results suggest that repeated administration of MSCs may prevent the deterioration of motor function and extend the lifespan in ALS. Supplementary Information The online version contains supplementary material available at 10.1186/s13041-021-00787-6.

OBJECTIVE Stroke is a major cause of long-term disability, and there are few effective treatments that improve function in patients during the chronic phase of stroke. Previous research has shown that single systemic infusion of mesenchymal stem cells (MSCs) improves motor function in acute and chronic cerebral ischemia models in rats. A possible mechanism that could explain such an event includes the enhanced neural connections between cerebral hemispheres that contribute to therapeutic effects. In the present study, repeated infusions (3 times at weekly intervals) of MSCs were administered in a rat model of chronic stroke to determine if multiple dosing facilitated plasticity in neural connections. METHODS The authors induced middle cerebral artery occlusion (MCAO) in rats and, 8 weeks thereafter, used them as a chronic stroke model. The rats with MCAO were randomized and intravenously infused with vehicle only (vehicle group); with MSCs at week 8 (single administration: MSC-1 group); or with MSCs at weeks 8, 9, and 10 (3 times, repeated administration: MSC-3 group) via femoral veins. Ischemic lesion volume and behavioral performance were examined. Fifteen weeks after induction of MCAO, the thickness of the corpus callosum (CC) was determined using Nissl staining. Immunohistochemical analysis of the CC was performed using anti-neurofilament antibody. Interhemispheric connections through the CC were assessed ex vivo by diffusion tensor imaging. RESULTS Motor recovery was better in the MSC-3 group than in the MSC-1 group. In each group, there was no change in the ischemic volume before and after infusion. However, both thickness and optical density of neurofilament staining in the CC were greater in the MSC-3 group, followed by the MSC-1 group, and then the vehicle group. The increased thickness and optical density of neurofilament in the CC correlated with motor function at 15 weeks following induction of MCAO. Preserved neural tracts that ran through interhemispheric connections via the CC were also more extensive in the MSC-3 group, followed by the MSC-1 group and then the vehicle group, as observed ex vivo using diffusion tensor imaging. CONCLUSIONS These results indicate that repeated systemic administration of MSCs over 3 weeks resulted in greater functional improvement as compared to single administration and/or vehicle infusion. In addition, administration of MSCs is associated with promotion of interhemispheric connectivity through the CC in the chronic phase of cerebral infarction.

Objective Reperfusion therapy is a standard therapeutic strategy for acute stroke. Non-favorable outcomes are thought to partially result from impaired microcirculatory flow in ischemic tissue. Intravenous infusion of mesenchymal stem cells (MSCs) reduces stroke volume and improves behavioral function in stroke. One suggested therapeutic mechanism is the restoration of the microvasculature. The goal of this study was to determine whether infused MSCs enhance the therapeutic efficacy of reperfusion therapy following stroke in rats. Methods First, to establish a transient middle cerebral artery occlusion (MCAO) model displaying approximately identical neurologic function and lesion volume as seen in permanent MCAO (pMCAO) at day 7 after stroke induction, we transiently occluded the MCA for 90, 110, and 120 minutes. We found that the 110-minute occlusion met these criteria and was used as the transient MCAO (tMCAO) model. Next, 4 MCAO groups were used to compare the therapeutic efficacy of infused MSCs: (1) pMCAO+vehicle, (2) tMCAO+vehicle, (3) pMCAO+MSC, and (4) tMCAO+MSC. Our ischemic model was a unique ischemic model system in which both pMCAO and tMCAO provided similar outcomes during the study period in the groups without MSC infusion groups. Behavioral performance, ischemic volume, and regional cerebral blood flow (rCBF) using arterial spin labeling–magnetic resonance imaging and histologic evaluation of microvasculature was performed. Results The behavioral function, rCBF, and restoration of microvasculature were greater in group 4 than in group 3. Thus, infused MSCs facilitated the therapeutic efficacy of MCA reperfusion in this rat model system. Conclusions Intravenous infusion of MSCs may enhance therapeutic efficacy of reperfusion therapy.

Intravenous infusion of mesenchymal stem cells (MSCs) has been reported to provide therapeutic efficacy via microvascular remodeling in a spontaneously hypertensive rat. In this study, we demonstrate that intravenous infusion of MSCs increased the survival rate in a spontaneously hypertensive (stroke prone) rat model in which organs including kidney, brain, heart and liver are damaged during aging due to spontaneous hypertension. Gene expression analysis indicated that infused MSCs activates transforming growth factor-β1-smad3/forkhead box O1 signaling pathway. Renal dysfunction was recovered after MSC infusion. Collectively, intravenous infusion of MSC may extend lifespan in this model system., Mesenchymal stem cell, cellular therapy, lifespan.

ALS is a devastating neurodegenerative disease with few curative strategies. Both sporadic and familial ALS display common clinical features that show progressive paralysis. The pathogenesis remains unclear, but disruption of the blood-spinal cord barrier (BSCB) may contribute to the degeneration of motor neurons. Thus, restoration of the disrupted BSCB and neuroprotection for degenerating motor neurons could be therapeutic targets. We tested the hypothesis that an intravenous infusion of MSCs would delay disease progression through the preservation of BSCB function and increased expression of a neurotrophic factor, neurturin, in SOD1G93A ALS rats. When the open-field locomotor function was under 16 on the Basso, Beattie, and Bresnahan (BBB) scoring scale, the rats were randomized into two groups; one received an intravenous infusion of MSCs, while the other received vehicle alone. Locomotor function was recorded using BBB scoring and rotarod testing. Histological analyses, quantitative reverse transcription-polymerase chain reaction (qRT-PCR), were performed. The MSC group exhibited reduced deterioration of locomotor activity compared to the vehicle group, which displayed progressive deterioration of hind limb function. We observed the protection of motor neuron loss and preservation of microvasculature using Evans blue leakage and immunohistochemical analyses in the MSC group. Confocal microscopy revealed infused green fluorescent protein+ (GFP+) MSCs in the spinal cord, and the GFP gene was detected by nested PCR. Neurturin expression levels were significantly higher in the MSC group. Thus, restoration of the BSCB and the protection of motor neurons might be contributing mechanisms to delay disease progression in SOD1G93A ALS rats.

Animal models are required to study the pathogenesis of brainstem ischemia and to develop new therapeutic approaches to promote functional recovery after ischemia in humans. Few models of brainstem ischemia are available, and they show great variability or cause early lethality. New, reliable animal models are therefore needed. By selectively ligating four points of the lower basilar artery, we developed a new focal basilar artery occlusion model that causes a localized brainstem ischemic lesion in female Sprague-Dawley rats. Analysis of ischemic lesion volume and neurological deficits over a period of 28 d showed that the rats present symptoms specific to this type of stroke while the ischemic lesion remains relatively unchanged over time. This procedure allows higher survival rates and extended observation periods compared with other models of brainstem ischemia. The procedure takes ~40 min, can be performed by researchers with basic surgical skills and does not require specialized surgical equipment. This protocol is highly reliable and will be useful to evaluate new therapeutic approaches to promote functional recovery in patients with brainstem ischemia.

Vincristine, a widely used chemotherapeutic agent, produces painful peripheral neuropathy. The underlying mechanisms are not well understood. In this study, we investigated whether voltage-gated sodium channels are involved in the development of vincristine-induced neuropathy. We established a mouse model in which repeated systemic vincristine treatment results in the development of significant mechanical allodynia. Histological examinations did not reveal major structural changes at proximal sciatic nerve branches or distal toe nerve fascicles at the vincristine dose used in this study. Immunohistochemical studies and in vivo two-photon imaging confirmed that there is no significant change in density or morphology of intra-epidermal nerve terminals throughout the course of vincristine treatment. These observations suggest that nerve degeneration is not a prerequisite of vincristine-induced mechanical allodynia in this model. We also provided the first detailed characterization of tetrodotoxin-sensitive (TTX-S) and resistant (TTX-R) sodium currents in dorsal root ganglion neurons following vincristine treatment. Accompanying the behavioural hyperalgesia phenotype, voltage-clamp recordings of small and medium dorsal root ganglion neurons from vincristine-treated animals revealed a significant upregulation of TTX-S Na+ current in medium but not small neurons. The increase in TTX-S Na+ current density is likely mediated by Nav1.6, because in the absence of Nav1.6 channels, vincristine failed to alter TTX-S Na+ current density in medium dorsal root ganglion neurons and, importantly, mechanical allodynia was significantly attenuated in conditional Nav1.6 knockout mice. Our data show that TTX-S sodium channel Nav1.6 is involved in the functional changes of dorsal root ganglion neurons following vincristine treatment and it contributes to the maintenance of vincristine-induced mechanical allodynia.

OBJECTIVEChildren who have experienced neonatal hypoxic-ischemic encephalopathy often develop cerebral palsy. Although many treatments have been performed, few effective therapies are available. In this study, the authors tested in rats with hypoxia-ischemia (HI) injuries the hypothesis that the systemic infusion of mesenchymal stem cells (MSCs) would result in functional improvement by facilitating neural compensation in the contralesional cortex.METHODSPostnatal day (P) 7 (P7) rats that had undergone unilateral hemisphere hypoxia-ischemia (modified Rice-Vannucci model) were randomly assigned to MSC-infused or vehicle-infused groups. MSCs (1.0 × 106/200 μL) or vehicle were intravenously infused on P10. Brain volume was measured using in vivo MRI on P8 and P35. On P35, the rats were sacrificed after their behavior was evaluated using a beam walk test, and their brains were then prepared for histological analyses.RESULTSThe MSC-treated group had fewer slips on the beam walk test compared to those in the vehicle group (p = 0.041). MRI was used to measure the volumes of the whole brain, contralesional brain (hemisphere), and residual brain regions of interest, and the results indicated increased brain volume after the intravenous MSC infusions. The histological analyses revealed increased thicknesses of the contralesional cortex and corpus callosum in the MSC group compared with those in the vehicle group (p = 0.021, p = 0.019), which confirmed the volume increases. In the contralesional cortex, the MSC-treated group exhibited significant increases in the numbers of NeuN-positive cells (p = 0.004) and synaptic puncta (p = 0.000) compared with the numbers observed in the vehicle group.CONCLUSIONSThe intravenous infusion of MSCs resulted in improvements in functional outcome, increased brain volume, and enhanced synaptogenesis in HI rats.

Systemic administration of mesenchymal stem cells (MSCs) following cerebral infarction exerts functional improvements. Previous research has suggested potential therapeutic mechanisms that promote neuroprotection and synaptogenesis. These include secretion of neurotrophic factors, remodeling of neural circuits, restoration of the blood brain barrier, reduction of inflammatory infiltration and demyelination, and elevation of trophic factors. In addition to these mechanisms, we hypothesized that restored interhemispheric bilateral motor cortex connectivity might be an additional mechanism of functional recovery. In the present study, we have shown, with both MRI diffusion tensor imaging (DTI) and neuroanatomical tracing techniques using an adeno-associated virus (AAV) expressing GFP, that there was anatomical restoration of cortical interhemispheric connections through the corpus callosum after intravenous infusion of MSCs in a rat middle cerebral artery occlusion (MCAO) stroke model. Moreover, the degree of connectivity was greater in the MSC-treated group than in the vehicle-infused group. In accordance, both the thickness of corpus callosum and synaptic puncta in the contralateral (non-infarcted) motor cortex connected to the corpus callosum were greater in the MSC-treated group than in the vehicle group. Together, these results suggest that distinct preservation of interhemispheric cortical connections through corpus callosum was promoted by intravenous infusion of MSCs. This anatomical preservation of the motor cortex in the contralateral hemisphere may contribute to functional improvements following MSC therapy for cerebral stroke.

To better understand the spatiotemporal course of radiation-induced central nervous system (CNS) vascular necrosis and assess the therapeutic potential of approaches for protecting against radiation-induced necrosis, adult female Sprague Dawley rats received 40 Gy surface dose centered on the T9 thoracic spinal cord segment. Locomotor function, blood-spinal cord barrier (BSCB) integrity and histology were evaluated throughout the study. No functional symptoms were observed for several months postirradiation. However, a sudden onset of paralysis was observed at approximately 5.5 months postirradiation. The progression rapidly led to total paralysis and death within less than 48 h of symptom onset. Open-field locomotor scores and rotarod motor coordination testing showed no evidence of neurological impairment prior to the onset of overt paralysis. Histological examination revealed minimal changes to the vasculature prior to symptom onset. However, Evans blue dye (EvB) extravasation revealed a progressive deterioration of BSCB integrity, beginning at one week postirradiation, affecting regions well outside of the irradiated area. Minocycline treatment significantly delayed the onset of paralysis. The results of this study indicate that extensive asymptomatic disruption of the blood-CNS barrier may precede onset of vascular breakdown by several months and suggests that minocycline treatment has a therapeutic effect by delaying radiation-induced necrosis after CNS irradiation.

Objective Status epilepticus (SE) causes neuronal cell death, aberrant mossy fiber sprouting (MFS), and cognitive deteriorations. The present study tested the hypothesis that systemically infused mesenchymal stem cells (MSCs) reduce epileptogenesis by inhibiting neuronal cell death and suppressing aberrant MFS, leading to cognitive function preservation in a rat model of epilepsy. Methods SE was induced using the lithium-pilocarpine injection model. The seizure frequency was scored using a video-monitoring system and the Morris water maze test was carried out to evaluate cognitive function. Comparisons were made between MSCs- and vehicle-infused rats. Immunohistochemical staining was performed to detect Green fluorescent protein (GFP)+ MSCs and to quantify the number of GAD67+ and NeuN+ neurons in the hippocampus. Manganese-enhanced magnetic resonance imaging (MEMRI) and Timm staining were also performed to assess the MFS. Results MSC infusion inhibited epileptogenesis and preserved cognitive function after SE. The infused GFP+ MSCs were accumulated in the hippocampus and were associated with the preservation of GAD67+ and NeuN+ hippocampal neurons. Furthermore, the MSC infusion suppressed the aberrant MFS in the hippocampus as evidenced by MEMRI and Timm staining. Conclusions This study demonstrated that the intravenous infusion of MSCs mitigated epileptogenesis, thus advancing MSCs as an effective approach for epilepsy in clinical practice.

Introduction Intravenous preload (delivered before cavernous nerve [CN] injury) of bone marrow–derived mesenchymal stem cells (MSCs) can prevent or decrease postoperative erectile dysfunction (J Sex Med 2015;12:1713–1721). In the present study, the potential therapeutic effects of intravenously administered MSCs on postoperative erectile dysfunction were evaluated in a rat model of CN injury. Methods Male Sprague-Dawley rats were randomized into 2 groups after electric CN injury. Intravenous infusion of bone marrow–derived MSCs (1.0 × 106 cells in Dulbecco's modified Eagle's medium 1 mL) or vehicle (Dulbecco's modified Eagle's medium 1 mL) was performed 3 hours after electrocautery-induced CN injury. Main Outcome Measures To assess erectile function, we measured intracavernous pressure at 4 weeks after MSC or vehicle infusion. Histologic examinations were performed to investigate neuronal innervation and inhibition of smooth muscle atrophy. Green fluorescent protein–positive bone marrow–derived MSCs were used for cell tracking. To investigate mRNA expression levels of neurotrophins in the major pelvic ganglia (MPGs), quantitative real-time polymerase chain reaction was performed. Results The decrease of intracavernous pressure corrected for arterial pressure and area under the curve of intracavernous pressure in the bone marrow–derived MSC group was significantly lower than that in the vehicle group at 4 weeks after infusion (P < .05). Retrograde neuronal tracing indicated that the MSC group had a larger number of FluoroGold-positive neurons in the MPGs compared with the vehicle group. The ratio of smooth muscle to collagen in the MSC group was significantly higher than in the vehicle group. Green fluorescent protein–positive bone marrow–derived MSCs were detected in the MPGs and injured CNs using confocal microscopy, indicating homing of cells to the MPGs and injured CNs. Brain-derived neurotrophic factor and glial cell-derived neurotrophic factor expression levels in the MPGs were significantly higher in the MSC group than in the vehicle group (P < .01). Conclusion Intravenous infusion of bone marrow–derived MSCs after CN injury might have therapeutic efficacy in experimental erectile dysfunction.

TNFα is persistently elevated in many injury and disease conditions. Previous reports of cytotoxicity of TNFα for oligodendrocytes and their progenitors suggest that the poor endogenous remyelination in patients with traumatic injury or multiple sclerosis may be due in part to persistent inflammation. Understanding the effects of inflammatory cytokines on potential cell therapy candidates is therefore important for evaluating the feasibility of their use. In this study, we assessed the effects of long term exposure to TNFα on viability, proliferation, migration and TNFα receptor expression of cultured rat olfactory ensheathing cells (OECs) and Schwann cells (SCs). Although OECs and SCs transplanted into the CNS produce similar myelinating phenotypes, and might be expected to have similar therapeutic uses, we report that they have very different sensitivities to TNFα. OECs exhibited positive proliferative responses to TNFα over a much broader range of concentrations than SCs. Low TNFα concentrations increased proliferation and migration of both OECs and SCs, but SC number declined in the presence of 100 ng/ml or higher concentrations of TNFα. In contrast, OECs exhibited enhanced proliferation even at high TNFα concentrations (up to 1 µg/ml) and showed no evidence of TNF cytotoxicity even at 4 weeks post-treatment. Furthermore, while both OECs and SCs expressed TNFαR1 and TNFαR2, TNFα receptor levels were downregulated in OECs after exposure to100 ng/ml TNFα for 5-7 days, but were either elevated or unchanged in SCs. These results imply that OECs may be a more suitable cell therapy candidate if transplanted into areas with persistent inflammation.

Axon visualization techniques are important in assessing the efficacy of interventional approaches to stimulate neural regeneration. While labeling of descending tracts in the spinal cord has been well established using intracortical injection of BDA (Biotin dextran amine), labeling of ascending sensory[for full text, please go to the a.m. URL], 47. Jahrestagung der Deutschen Gesellschaft der Plastischen, Rekonstruktiven und Ästhetischen Chirurgen (DGPRÄC), 21. Jahrestagung der Vereinigung der Deutschen Ästhetisch-Plastischen Chirurgen (VDÄPC)

Development of prognostic biomarkers for the detection of prenatally damaged neurons before manifestations of postnatal disorders is an essential step for prevention and treatment of susceptible individuals. We have developed a versatile fluorescence reporter system in mice enabling detection of Heat Shock Factor 1 activation in response to prenatal cellular damage caused by exposure to various harmful chemical or physical agents. Using an intrautero electroporation-mediated reporter assay and transgenic reporter mice, we are able to identify neurons that survive prenatal exposure to harmful agents but remain vulnerable in postnatal life. This system may provide a powerful tool for exploring the pathogenesis and treatment of multiple disorders caused by exposure to environmental stress before symptoms become manifested, exacerbated, and/or irreversible.

Background Intravenous infusion of mesenchymal stem cells (MSCs) derived from adult bone marrow elicits functional recovery in rat stroke models and clinical studies in patients are ongoing. Brain derived neurotrophic factor (BDNF) is a neurotrophic factor produced by MSCs and may contribute to their therapeutic efficacy. The purpose of the current study was to determine if BDNF is elevated in infarcted brain and in which compartment of blood (plasma or serum) after intravenous MSC infusion in a middle cerebral artery occlusion (MCAO) model in the rat. Methods In rats, a permanent middle cerebral artery occlusion (MCAO) was induced by intraluminal vascular occlusion with a microfilament and MSCs were intravenously administered 6 h after right MCAO induction. Enzyme-linked immunosorbent assay (ELISA) analysis of brain, serum and plasma BDNF were performed after the MSC infusion following the MCAO induction. Lesion volume was assessed using magnetic resonance imaging. Functional outcome was assessed using the Limb Placement Test. Results Infused MSCs reduced lesion volume and elicited functional improvement compared to the vehicle infused group. ELISA analysis of the MSC treated group revealed an increase BDNF levels in the infarcted hemisphere of the brain and plasma, but not in serum. The MSC group showed a greater increase in BDNF levels than sham control. In the MSC group, the expression of increased plasma BDNF levels correlated with increased brain BDNF levels. Conclusions These results support the hypothesis that BDNF levels in plasma, but not serum, may be more appropriate to detect circulating BDNF in vivo following MSC infusion in a cerebral infarction rat model of ischemic stroke. Further, plasma BDNF might reflect in vivo functional viability of infused MSCs after stroke.

Background Although spinal cord injury (SCI) is a major cause of disability, current therapeutic options remain limited. Recent progress in cellular therapy with mesenchymal stem cells (MSCs) has provided improved function in animal models of SCI. We investigated the safety and feasibility of intravenous infusion of MSCs for SCI patients and assessed functional status after MSC infusion. Methods In this phase 2 study of intravenous infusion of autologous MSCs cultured in auto-serum, a single infusion of MSCs under Good Manufacturing Practice (GMP) production was delivered in 13 SCI patients. In addition to assessing feasibility and safety, neurological function was assessed using the American Spinal Injury Association Impairment Scale (ASIA), International Standards for Neurological and Functional Classification of Spinal Cord (ISCSCI-92). Ability of daily living was assessed using Spinal Cord Independence Measure (SCIM-III). The study protocol was based on advice provided by the Pharmaceuticals and Medical Devices Agency in Japan. The trial was registered with the Japan Medical Association (JMA-IIA00154). Results No serious adverse events were associated with MSC injection. There was neurologic improvement based on ASIA grade in 12 of the 13 patients at six months post-MSC infusion. Five of six patients classified as ASIA A prior to MSC infusion improved to ASIA B (3/6) or ASIA C (2/6), two ASIA B patients improved to ASIA C (1/2) or ASIA D (1/2), five ASIA C patients improved and reached a functional status of ASIA D (5/5). Notably, improvement from ASIA C to ASIA D was observed one day following MSC infusion for all five patients. Assessment of both ISCSCI-92, SCIM-III also demonstrated functional improvements at six months after MSC infusion, compared to the scores prior to MSC infusion in all patients. Conclusion While we emphasize that this study was unblinded, and does not exclude placebo effects or a contribution of endogenous recovery or observer bias, our observations provide evidence supporting the feasibility, safety and functional improvements of infused MSCs into patients with SCI.

Arteriovenous malformations (AVMs) are congenital abnormal vessels that shunt blood directly from the arterial to the venous system without a capillary bed. The underlying pathology of AVMs is not fully understood. The objective of the study was to determine the association between the expression patterns of tissue factor (TF) and interleukin-6 (IL-6) in AVMs with clinical and pathological findings. Eighteen cases of sporadic AVM with operative specimens were included in this study. The expression of messenger RNA (mRNA) of TF and IL-6 was assayed, and association with clinical factors was investigated. The distribution of TF and IL-6 was examined with immunofluorescence. The mRNA expression of TF was significantly higher in AVM specimens than in control tissues (P = 0.002) and significantly higher in the symptomatic group than in the asymptomatic group (P = 0.037). The mRNA expression of IL-6 was likewise significantly higher in AVM specimens than in control tissues (P = 0.038). Examination of immunostained sections indicated that TF+ cells were also positive for IL-6 and were distributed around normal endothelial cells and pericytes. Moreover, TF+/IL-6+ cells also expressed CD31, vascular endothelial growth factor receptor 2 (VEGFR2), and platelet-derived growth factor receptor beta (PDGFR-beta). These results suggest that TF is elevated in AVMs and that it mediates symptomatic events. IL-6 is associated with the angiogenic activity of TF, and both are present in the same abnormal endothelial cells and pericytes. These factors may have interactive effects and may serve in a prognostic role for AVMs.

Ischemic spinal cord injury (iSCI) is a devastating complication of aortic surgery, with few strategies for prevention. Intravenous infusion of mesenchymal stem cells (MSCs) for iSCI has been shown to provide functional improvement through protection of gray matter. The purpose of this study was to investigate additional mechanisms which may exert therapeutic efficacy in iSCI. Severe iSCI was created to occlude the descending aorta, which was cross-clamped 5 mm distal to the left subclavian artery for 16 min. One day after iSCI induction, iSCI rats were randomized into two groups: one received intravenous infusion of MSCs (MSC-group), the other received vehicle (no cells; vehicle-group). Locomotor function and in vivo MRI were recorded. HE, Nissl and toluidine blue stainings, immunohistochemical analysis, diffusion tensor imaging (DTI), and the assessment of blood-spinal cord barrier (BSCB) stability were performed. MSC treated animals exhibited gradual improvement in hind-limb locomotor function during the 4-week study period; however the vehicle-treated group displayed persistent motor deficits. In the MSC-treated group we observed the protection of white and gray matter volume reduction of axonal and neuronal loss or degeneration and preservation of microvasculature including BSCB function. Intravenous infusion of MSCs may provide therapeutic efficacy to improve functional outcomes in a rat model of severe iSCI via protection of white and gray matter.

Recurrence is inevitable in glioblastomas (GBMs) and requires multifactorial processes. One of the factors that cause recurrence is the strong migratory capacity of GBM cells. We recently reported that actin, alpha, cardiac muscle 1 (ACTC1) could serve as a marker to detect GBM migration in clinical cases.This study aimed to clarify whether the knockdown of highly expressed ACTC1 can inhibit the migratory capacity of cells in the GBM cell line.ACTC1 expression was examined using immunocytochemistry and droplet digital polymerase chain reaction. The motility of GBM cells that were either treated with siRNA to knock down ACTC1 or untreated were investigated using a time-lapse study in vitro.The relatively high ACTC1 expression was confirmed in a GBM cell line, i.e., U87MG. The ACTC1 expression in U87MG cells was significantly inhibited by ACTC1-siRNA (p 0.05). A cell movement tracking assay using time-lapse imaging demonstrated the inhibition of U87MG cell migration by ACTC1 knockdown. The quantitative cell migration analysis demonstrated that the distance traversed during 72 h was 3607 ± 458 (median ± SD) μm by untreated U87MG cells and 3570 ± 748 μm by negative control siRNA-treated cells. However, the distance migrated by ACTC1-siRNA-treated cells during 72 h was significantly shorter (1265 ± 457 μm, p 0.01) than the controls.ACTC1 knockdown inhibits U87MG cell migration.

OBJECTIVEIntravenous infusion of mesenchymal stem cells (MSCs) derived from adult bone marrow improves behavioral function in rat models of cerebral infarction. Although clinical studies are ongoing, most studies have focused on the acute or subacute phase of stroke. In the present study, MSCs derived from bone marrow of rats were intravenously infused 8 weeks after the induction of a middle cerebral artery occlusion (MCAO) to investigate whether delayed systemic injection of MSCs improves functional outcome in the chronic phase of stroke in rats.METHODSEight weeks after induction of the MCAO, the rats were randomized and intravenously infused with either MSCs or vehicle. Ischemic volume and behavioral performance were examined. Blood-brain barrier (BBB) integrity was assessed by quantifying the leakage of Evans blue into the brain parenchyma after intravenous infusion. Immunohistochemical analysis was also performed to evaluate the stability of the BBB.RESULTSMotor recovery was better in the MSC-treated group than in the vehicle-treated group, with rapid improvement (evident at 1 week post-infusion). In MSC-treated rats, reduced BBB leakage and increased microvasculature/repair and neovascularization were observed.CONCLUSIONSThese results indicate that the systemic infusion of MSCs results in functional improvement, which is associated with structural changes in the chronic phase of cerebral infarction, including in the stabilization of the BBB.

OBJECTIVEMorbidity and mortality in patients with posterior circulation stroke remains an issue despite advances in acute stroke therapies. The intravenous infusion of mesenchymal stem cells (MSCs) elicits therapeutic efficacy in experimental supratentorial stroke models. However, since there are few reliable animal models of ischemia in the posterior circulation, the therapeutic approach with intravenous MSC infusion has not been tested. The objective of this study was to test the hypothesis that intravenously infused MSCs provide functional recovery in a newly developed model of brainstem infarction in rats.METHODSBasilar artery (BA) occlusion (BAO) was established in rats by selectively ligating 4 points of the proximal BA with 10-0 nylon monofilament suture. The intravenous infusion of MSCs was performed 1 day after BAO induction. MRI and histological examinations were performed to assess ischemic lesion volume, while multiple behavioral tests were performed to evaluate functional recovery.RESULTSThe MSC-treated group exhibited a greater reduction in ischemic lesion volume, while behavioral testing indicated that the MSC-infused group had greater improvement than the vehicle group 28 days after the MSC infusion. Accumulated infused MSCs were observed in the ischemic brainstem lesion.CONCLUSIONSInfused MSCs may provide neuroprotection to facilitate functional outcomes and reduce ischemic lesion volume as evaluated in a newly developed rat model of persistent BAO.

Introduction We evaluated the potential preventive effects and mechanisms of intravenously preloaded mesenchymal stem cells (MSCs) for erectile dysfunction (ED) in a cavernous nerve (CN) injury model. Methods Male Sprague–Dawley (SD) rats were used for this study. Rats were randomized into two groups. One group was intravenously preloaded with MSCs (1.0 × 106 cells in 1 mL total fluid volume) and the other was infused with medium alone (1 mL Dulbecco's modified Eagle's medium [DMEM]) for sham control, respectively. Crushed CN injury was induced immediately after infusion. The surgeon was blind to the experimental conditions (MSC or medium). Main Outcome Measures To assess erectile function, we measured the intracavernous pressure (ICP) and arterial pressure (AP) at 1 hour and 2 weeks after CN injury. After measuring the initial ICP/AP of pre-injury (normal) male SD rats, they were randomized into the two groups and infused with MSCs or medium. PKH26-labelled MSCs were used for tracking. To investigate the mRNA expression levels of neurotrophins in the major pelvic ganglia (MPG), we performed real-time quantitative real-time polymerase chain reaction. Results The reduction of ICP/AP and area under the curve of ICP (ICP-AUC) in the MSC group was significantly lower than in the DMEM group (P Conclusion Intravenous preload of MSCs before a CN injury may prevent or reduce experimental ED.

Large animal and primate models of spinal cord injury (SCI) are being increasingly utilized for the testing of novel therapies. While these represent intermediary animal species between rodents and humans and offer the opportunity to pose unique research questions prior to clinical trials, the role that such large animal and primate models should play in the translational pipeline is unclear. In this initiative we engaged members of the SCI research community in a questionnaire and round-table focus group discussion around the use of such models. Forty-one SCI researchers from academia, industry, and granting agencies were asked to complete a questionnaire about their opinion regarding the use of large animal and primate models in the context of testing novel therapeutics. The questions centered around how large animal and primate models of SCI would be best utilized in the spectrum of preclinical testing, and how much testing in rodent models was warranted before employing these models. Further questions were posed at a focus group meeting attended by the respondents. The group generally felt that large animal and primate models of SCI serve a potentially useful role in the translational pipeline for novel therapies, and that the rational use of these models would depend on the type of therapy and specific research question being addressed. While testing within these models should not be mandatory, the detection of beneficial effects using these models lends additional support for translating a therapy to humans. These models provides an opportunity to evaluate and refine surgical procedures prior to use in humans, and safety and bio-distribution in a spinal cord more similar in size and anatomy to that of humans. Our results reveal that while many feel that these models are valuable in the testing of novel therapies, important questions remain unanswered about how they should be used and how data derived from them should be interpreted.

Intravenous infusion of mesenchymal stem cells (MSCs) has been shown to reduce the severity of experimental spinal cord injury (SCI), but mechanisms are not fully understood. One important consequence of SCI is damage to the microvasculature and disruption of the blood spinal cord barrier (BSCB). In the present study we induced a contusive SCI at T9 in the rat and studied the effects of intravenous MSC infusion on BSCB permeability, microvascular architecture and locomotor recovery over a 10 week period. Intravenously delivered MSCs could not be identified in the spinal cord, but distributed primarily to the lungs where they survived for a couple of days. Spatial and temporal changes in BSCB integrity were assessed by intravenous infusions of Evans blue (EvB) with in vivo and ex vivo optical imaging and spectrophotometric quantitation of EvB leakage into the parenchyma. SCI resulted in prolonged BSCB leakage that was most severe at the impact site but disseminated extensively rostral and caudal to the lesion over 6 weeks. Contused spinal cords also showed an increase in vessel size, reduced vessel number, dissociation of pericytes from microvessels and decreases in von Willebrand factor (vWF) and endothelial barrier antigen (EBA) expression. In MSC-treated rats, BSCB leakage was reduced, vWF expression was increased and locomotor function improved beginning 1 week post-MSC infusion, i.e., 2 weeks post-SCI. These results suggest that intravenously delivered MSCs have important effects on reducing BSCB leakage which could contribute to their therapeutic efficacy.

Background SERPINA1 plays an anti-inflammatory role in protecting tissues from proteolytic mechanisms. SERPINA1 is positive in gliomas by immunohistochemical analysis; however, the role of SERPINA1, including the relationship with prognosis, has been uncertain. In recent years, digital polymerase chain reaction (PCR) has provided ultra-sensitive assessment of messenger RNA expression from formalin-fixed paraffin-embedded (FFPE) tissues. Objective In this study, we quantitatively determined the expression of SERPINA1 in high-grade gliomas (HGGs) using digital PCR, and we analyzed its relationship with prognosis. Methods Twenty-nine FFPE surgical samples from patients with HGGs (7 of World Health Organization [WHO] grade III and 22 of WHO grade IV), and human glioblastoma cell lines, U87 and U118, were used for analysis. A qualitative assessment using immunostaining and quantitative assessment using digital PCR were performed to assess the expression of SERPINA1. Results The expression of SERPINA1 was demonstrated in glioma tissues and glioblastoma multiforme cell lines by immunostaining. Digital PCR analysis showed that SERPINA1 was expressed in 14.3% and 63.6% of the tissues from patients with grade III and grade IV HGG, respectively (P = 0.035). The median overall survival of 38.8 months in the low SERPINA1 expression group was longer than that of 15.3 months in the high expression group (P = 0.030). Conclusions The frequency and the amount of SERPINA1 expression were higher in grade IV than in grade III HGGs. The high expression of SERPINA1 indicates a poor prognosis of HGGs.