Bone marrow mesenchymal stem cells from healthy donors and sporadic amyotrophic lateral sclerosis patients

Effect of mesenchymal stromal cell transplantation on long-term survival in amyotrophic lateral sclerosis

BACKGROUND AIMS

Thanks to their immunomodulatory, tissue-protective and regenerative properties, mesenchymal stromal cells (MSCs) are a promising approach for amyotrophic lateral sclerosis (ALS); however, trials are limited and few follow-up studies have been published. This post-hoc analysis aims to describe the potential long-term effects of MSCs in ALS, analyzing data from two phase 1 clinical trials in ALS patients conducted by our group in 2002 and 2006.

METHODS

We conducted two consecutive phase 1 prospective, open, pilot clinical trials, enrolling a total of 19 ALS patients. We followed patients for the duration of the disease. For each patient, we used the European Network to Cure ALS (ENCALS) survival prediction model to retrospectively calculate the expected survival at diagnosis. We then compared the predicted disease duration with the observed survival, analyzing patients at a single-patient level.

RESULTS

Using the ENCALS model, we predicted short survival in one patient, intermediate survival in three patients, long survival in three patients and very long survival in 12 patients. The difference between predicted and observed survival for the whole group was significant and demonstrated a mean predicted survival of 70.79 months (standard deviation [SD], 27.53) and a mean observed survival of 118.8 months (SD, 89.26) (P = 0.016). Based on the monthly ALS Functional Rating Scale-Revised progression rate (median, 0.64/month), we considered 10 of 19 patients slow progressors and nine of 19 patients fast progressors. Of the slow progressors, eight of 10 (80%) had significantly increased disease duration compared with predicted, and only two (20%) had decreased estimated disease duration. By contrast, five of nine (55%) fast progressors had increased disease duration, whereas four (45%) had decreased disease duration. To date, four patients are still alive.

CONCLUSIONS

The current study represents the first very long-term analysis of survival as an effect of MSC focal transplantation in the central nervous system of ALS patients, demonstrating that MSC transplantation could potentially slow down ALS progression and improve survival. Due to the interindividual variability in clinical course, at the current state of our knowledge, we cannot generalize the results, but these data provide new insights for planning the next generation of efficacy MSC clinical trials in ALS.

Cell therapy in ALS: An update on preclinical and clinical studies

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by the loss of motor neurons and neuromuscular impairment leading to complete paralysis, respiratory failure and premature death. The pathogenesis of the disease is multifactorial and noncell-autonomous involving the central and peripheral compartments of the neuromuscular axis and the skeletal muscle. Advanced clinical trials on specific ALS-related pathways have failed to significantly slow the disease. Therapy with stem cells from different sources has provided a promising strategy to protect the motor units exerting their effect through multiple mechanisms including neurotrophic support and excitotoxicity and neuroinflammation modulation, as evidenced from preclinical studies. Several phase I and II clinical trial of ALS patients have been developed showing positive effects in terms of safety and tolerability. However, the modest results on functional improvement in ALS patients suggest that only a coordinated effort between basic and clinical researchers could solve many problems, such as selecting the ideal stem cell source, identifying their mechanism of action and expected clinical outcomes. A promising approach may be stem cells selected or engineered to deliver optimal growth factor support at multiple sites along the neuromuscular pathway. This review covers recent advances in stem cell therapies in animal models of ALS, as well as detailing the human clinical trials that have been done and are currently undergoing development.

Storage of Mutant Human SOD1 in Non-Neural Cells from the Type-1 Amyotrophic Lateral Sclerosis ratG93A Model Correlated with the Lysosomes' Dysfunction

Herein, we explored the impact of the lysosome dysfunction during the progression of Amyotrophic Lateral Sclerosis type-1 (ALS1). We conducted the study in non-neural cells, primary fibroblasts (rFFFs), and bone marrow-mesenchymal stem cells (rBM-MSCs), isolated from the animal model rat^G93A for ALS1 at two stages of the disease: Pre-symptomatic-stage (ALS1-PreS) and Terminal-stage (ALS1-EndS). We documented the storage of human mutant Superoxide Dismutase 1, SOD1^G93A (SOD1*) in the lysosomes of ALS1-rFFFs and ALS1-rBM-MSCs and demonstrated the hallmarks of the disease in non-neural cells as in rat^G93A-ALS1-tissues. We showed that the SOD1* storage is associated with the altered glycohydrolases and proteases levels in tissues and both cell types from ALS1-PreS to ALS1-EndS. Only in ALS1-rFFFs, the lysosomes lost homeostasis, enlarge drastically, and contribute to the cell metabolic damage. Contrariwise, in ALS1-rBM-MSCs, we found a negligible metabolic dysfunction, which makes these cells’ status similar to WT. We addressed this phenomenon to a safety mechanism perhaps associated with an enhanced lysosomal autophagic activity in ALS1-rBM-MSCs compared to ALS1-rFFFs, in which the lysosomal level of LC3-II/LC3I was comparable to that of WT-rFFFs. We suggested that the autophagic machinery could balance the storage of SOD1* aggregates and the lysosomal enzyme dysfunction even in ALS1-EndS-stem cells.

Mesenchymal Stem Cells as a Gene Delivery Tool: Promise, Problems, and Prospects

The cell-based approach in gene therapy arises as a promising strategy to provide safe, targeted, and efficient gene delivery. Owing to their unique features, as homing and tumor-tropism, mesenchymal stem cells (MSCs) have recently been introduced as an encouraging vehicle in gene therapy. Nevertheless, non-viral transfer of nucleic acids into MSCs remains limited due to various factors related to the main stakeholders of the process (e.g., nucleic acids, carriers, or cells). In this review, we have summarized the main types of nucleic acids used to transfect MSCs, the pros and cons, and applications of each. Then, we have emphasized on the most efficient lipid-based carriers for nucleic acids to MSCs, their main features, and some of their applications. While a myriad of studies have demonstrated the therapeutic potential for engineered MSCs therapy in various illnesses, optimization for clinical use is an ongoing challenge. On the way of improvement, genetically modified MSCs have been combined with various novel techniques and tools (e.g., exosomes, spheroids, 3D-Bioprinting, etc.,) aiming for more efficient and safe applications in biomedicine.

Mesenchymal Stem Cells: A Potential Therapeutic Strategy for Neurodegenerative Diseases

Neurodegenerative disease is a kind of chronic, progressive nervous system disease characterized by neuron degeneration or apoptosis. Current treatments cannot prevent the development of the disease. Possible alternative treatments include cell therapy, especially with the use of mesenchymal stem cells (MSCs). MSCs are pluripotent stem cells with capacities for self-renewal and multidirectional differentiation. MSCs may serve as a reliable source of neural cells for potential cell replacement therapy or regenerative medicine treatment. Here, we summarized the therapeutic mechanisms of MSCs and how they can contribute to the development of treatments for neurodegenerative diseases.

Mesenchymal Stem Cells: The Past Present and Future

The biomedical applications of mesenchymal stem cells (MSCs) have gained expanding attention over the past three decades. MSCs are easily obtained from various tissue types (e.g. bone marrow, fat, cord blood, etc.), are capable of self-renewal, and could be induced to differentiate into several cell lineages for countless biomedical applications. In addition, when transplanted, MSCs are not detected by immune surveillance, thus do not lead to graft rejection. Moreover, they can home towards affected tissues and induce their therapeutic effect in a cell-base and/or a cell-free manner. These properties, and many others, have made MSCs appealing therapeutic cell candidates (for cell and/or gene therapy) in myriad clinical conditions. However, similar to any other therapeutic tool, MSCs still have their own limitations and grey areas that entail more research for better understanding and optimization. Herein, we present a brief overview of various pre-clinical/clinical applications of MSCs in regenerative medicine and discuss limitations and future challenges.

Stem Cell Transplantation for Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a motor neuronal degeneration disease, in which the death of motor neurons causes lost control of voluntary muscles. The consequence is weakness of muscles with a wide range of disabilities and eventually death. Most patients died within 5 years after diagnosis, and there is no cure for this devastating neurodegenerative disease up to date. Stem cells, including non-neural stem cells and neural stem cells (NSCs) or neural progenitor cells (NPCs), are very attractive cell sources for potential neuroprotection and motor neuron replacement therapy which bases on the idea that transplant-derived and newly differentiated motor neurons can replace lost motor neurons to re-establish voluntary motor control of muscles in ALS. Our recent studies show that transplanted NSCs or NPCs not only survive well in injured spinal cord, but also function as neuronal relays to receive regenerated host axonal connection and extend their own axons to host for connectivity, including motor axons in ventral root. This reciprocal connection between host neurons and transplanted neurons provides a strong rationale for neuronal replacement therapy for ALS to re-establish voluntary motor control of muscles. In addition, a variety of new stem cell resources and the new methodologies to generate NSCs or motor neuron-specific progenitor cells have been discovered and developed. Together, it provides the basis for motor neuron replacement therapy with NSCs or NPCs in ALS.

Mesenchymal Stem Cells: A Potential Therapeutic Approach for Amyotrophic Lateral Sclerosis?

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by the degeneration of both upper and lower motor neurons. Patients show both motor and extra-motor symptoms. A cure is not available at this time, and the disease leads to death within 3-5 years, mainly due to respiratory failure. Stem cell therapy is arising as a new promising approach for the treatment of neurodegenerative disorders. In particular, mesenchymal stem cells (MSCs) seem the most suitable type of stem cells, thanks to their demonstrated beneficial effects in different experimental models, to the easy availability, and to the lack of ethical problems. In this review, we focused on the studies involving ALS rodent models and clinical trials in order to understand the potential beneficial effects of MSC transplantation. In different ALS rodent models, the administration of MSCs induced a delay in disease progression and at least a partial recovery of the motor function. In addition, clinical trials evidenced the feasibility and safety of MSC transplantation in ALS patients, given that no major adverse events were recorded. However, only partial improvements were shown. For this reason, more studies and trials are needed to clarify the real effectiveness of MSC-based therapy in ALS.

Immunomodulatory Properties of Bone Marrow Mesenchymal Stem Cells from Patients with Amyotrophic Lateral Sclerosis and Healthy Donors

Pathogenesis of amyotrophic lateral sclerosis (ALS) involves several mechanisms resulting in a shift from a neuroprotective to a neurotoxic immune reaction. A promising tool for ALS treatment is represented by mesenchymal stem cells (MSCs), which possess both regenerative potential and immunomodulatory properties. In this study, we aimed to compare the immunomodulatory properties of MSCs isolated from the bone marrow of patients suffering from ALS and healthy donors. Moreover, the influence of proinflammatory cytokines on the immunoregulatory functions of MSCs was also evaluated. We found that MSCs from ALS patients and healthy donors comparably affected mitogen-stimulated peripheral blood mononuclear cells and reduced the percentage of T helper (Th)1, Th17 and CD8⁺CD25⁺ lymphocytes. These MSCs also equally increased the percentage of Th2 and CD4⁺FOXP3⁺ T lymphocytes. On the other hand, MSCs from ALS patients decreased more strongly the production of tumour necrosis factor-α than MSCs from healthy donors, but this difference was abrogated in the case of MSCs stimulated with cytokines. Significant differences between cytokine-treated MSCs from ALS patients and healthy donors were detected in the effects on the percentage of CD8⁺CD25⁺ and CD4⁺FOXP3⁺ T lymphocytes. In general, treatment of MSCs with cytokines results in a potentiation of their effects, but in the case of MSCs from ALS patients, it causes stagnation or even restriction of some of their immunomodulatory properties. We conclude that MSCs from ALS patients exert comparable immunomodulatory effects to MSCs from healthy donors, but respond differently to stimulation with proinflammatory cytokines. Graphical Abstract Treatment of mesenchymal stem cells (MSCs) with cytokines results in a potentiation of their effects, but in the case of MSCs from amyotrophic lateral sclerosis (ALS) patients, it causes stagnation (an equal reduction of the percentage of CD8⁺CD25⁺ T lymphocytes) or even restriction (no increase of proportion of CD4⁺FOXP3⁺ T lymphocytes) of some of their immunomodulatory properties. It means that MSCs from ALS patients exert comparable immunomodulatory effects to MSCs from healthy donors, but respond differently to stimulation with proinflammatory cytokines.

Characterisation of mesenchymal stem cells from patients with amyotrophic lateral sclerosis

AIMS

Mesenchymal stem cells (MSCs) have recently been tested in clinical trials to treat severe diseases, including amyotrophic lateral sclerosis (ALS). Since autologous MSCs are frequently used for therapy, we aimed to evaluate the possible influence of the disease on characteristics and function of these cells.

METHODS

MSCs were isolated from the bone marrow of patients with ALS and compared with MSCs from healthy controls (HC). The cells were tested for phenotype, growth properties, differentiation ability, metabolic activity, secretory potential, expression of genes for immunomodulatory molecules and for the ability to regulate proliferation of mitogen-stimulated peripheral blood leucocytes. MSCs from patients with ALS and HC were either unstimulated or treated with proinflammatory cytokines for 24 hours before testing.

RESULTS

MSCs isolated from patients with ALS have a higher differentiation potential into adipocytes, express elevated levels of mRNA for interleukin-6, but produce less hepatocyte growth factor than MSCs from HC. On the other hand, there were no significant differences between MSCs from patients with ALS and HC in the expression of phenotypic markers, growth properties, metabolic activity, osteogenic differentiation potential and immunoregulatory properties.

CONCLUSIONS

The results suggest that, in spite of some differences in cytokine production, MSCs from patients with ALS can be useful as autologous cells in therapy of ALS.

Stemness Characteristics of Periodontal Ligament Stem Cells from Donors and Multiple Sclerosis Patients: A Comparative Study

Multiple sclerosis (MS) is the most prevalent and progressive autoimmune disease that affects the central nervous system, and currently, no drug is available for the treatment. Stem cell therapy has received substantial attention in MS treatment. Recently, we demonstrated the immunosuppressive effects of mesenchymal stem cells derived from neural crest-originated human periodontal ligament tissue (hPDLSCs) in an in vivo model of MS. In the present study, we comparatively investigated the stemness properties of hPDLSCs derived from healthy donors and relapsing-remitting MS patients. Stem cell marker expression, cell proliferation, and differentiation capacity were studied. We found that both donor- and MS patient-derived hPDLSCs at early passage 2 showed similar expression of surface antigen markers and cell proliferation rate. Significant level of osteogenic, adipogenic, chondrogenic, and neurogenic differentiation capacities was observed in both donor- and MS patient-derived hPDLSCs. Interestingly, these cells maintained the stemness properties even at late passage 15. Senescence markers p16 and p21 expression was considerably enhanced in passage 15. Our results propose that hPDLSCs may serve as simple and potential autologous stem cell niche, which may help in personalized stem cell therapy for MS patients.

Advances, challenges and future directions for stem cell therapy in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative condition where loss of motor neurons within the brain and spinal cord leads to muscle atrophy, weakness, paralysis and ultimately death within 3–5 years from onset of symptoms. The specific molecular mechanisms underlying the disease pathology are not fully understood and neuroprotective treatment options are minimally effective.

In recent years, stem cell transplantation as a new therapy for ALS patients has been extensively investigated, becoming an intense and debated field of study. In several preclinical studies using the SOD1^G93A mouse model of ALS, stem cells were demonstrated to be neuroprotective, effectively delayed disease onset and extended survival. Despite substantial improvements in stem cell technology and promising results in preclinical studies, several questions still remain unanswered, such as the identification of the most suitable and beneficial cell source, cell dose, route of delivery and therapeutic mechanisms. This review will cover publications in this field and comprehensively discuss advances, challenges and future direction regarding the therapeutic potential of stem cells in ALS, with a focus on mesenchymal stem cells. In summary, given their high proliferation activity, immunomodulation, multi-differentiation potential, and the capacity to secrete neuroprotective factors, adult mesenchymal stem cells represent a promising candidate for clinical translation. However, technical hurdles such as optimal dose, differentiation state, route of administration, and the underlying potential therapeutic mechanisms still need to be assessed.

The use of mesenchymal stem cells (MSCs) for amyotrophic lateral sclerosis (ALS) therapy – a perspective on cell biological mechanisms

Recent clinical trials of mesenchymal stem cells (MSCs) transplantation have demonstrated procedural safety and clinical proof of principle with a modest indication of benefit in patients with amyotrophic lateral sclerosis (ALS). While replacement therapy remained unrealistic, the clinical efficacy of this therapeutic option could be potentially enhanced if we could better decipher the mechanisms underlying some of the beneficial effects of transplanted cells, and work toward augmenting or combining these in a strategic manner. Novel ways whereby MSCs could act in modifying disease progression should also be explored. In this review, I discuss the known, emerging and postulated mechanisms of action underlying effects that transplanted MSCs may exert to promote motor neuron survival and/or to encourage regeneration in ALS. I shall also speculate on how transplanted cells may alter the diseased environment so as to minimize non-neuron cell autonomous damages by immune cells and astrocytes.

Drugs in clinical development for the treatment of amyotrophic lateral sclerosis

INTRODUCTION

Amyotrophic Lateral Sclerosis (ALS) is a fatal motor neuron progressive disorder for which no treatment exists to date. However, there are other investigational drugs and therapies currently under clinical development may offer hope in the near future. Areas covered: We have reviewed all the ALS ongoing clinical trials (until November 2016) and collected in Clinicaltrials.gov or EudraCT. We have described them in a comprehensive way and have grouped them in the following sections: biomarkers, biological therapies, cell therapy, drug repurposing and new drugs. Expert opinion: Despite multiple obstacles that explain the absence of effective drugs for the treatment of ALS, joint efforts among patient's associations, public and private sectors have fueled innovative research in this field, resulting in several compounds that are in the late stages of clinical trials. Drug repositioning is also playing an important role, having achieved the approval of some orphan drug applications, in late phases of clinical development. Endaravone has been recently approved in Japan and is pending in USA.

Regenerative capacity of autologous stem cell transplantation in elderly: a report of biomedical outcomes

The occurrence of chronic diseases such as neurological, metabolic and cardiovascular degenerative disorders increases with age. Cell therapy is an emerging approach to the treatment of these conditions. Of particular interest is the application of autologous stem cells because it eliminates post-transplantation immune rejection and there are less ethical concerns associated with their use. The regenerative capacity of stem cells harvested from elderly people is however controversial. In this review, we analyze if self-renewal potential, differentiation capability and expression of stemness genes in stem cells collected from elderly patients validate their application in clinical trials and examine the results.

The secretome of periodontal ligament stem cells from MS patients protects against EAE

Manipulation of stem cells or stem cells-derived secretome has emerged as a novel alternative therapeutic option for multiple sclerosis (MS). Here we show that human periodontal ligament stem cells (hPDLSCs)-derived conditioned medium (hPDLSCs-CM) and purified exosomes/microvesicles (hPDLSCs-EMVs) obtained from Relapsing Remitting (RR)-MS patients and healthy donors block experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, by inducing anti-inflammatory and immunosuppressive effects in spinal cord and spleen, and reverse disease progression by restoring tissue integrity via remyelination in the spinal cord. We show that hPDLSCs-CM and hPDLSCs-EMVs reduce pro-inflammatory cytokines IL-17, IFN-γ, IL-1β, IL-6, TNF-α, and induce anti-inflammatory IL-10. In addition, apoptosis related STAT1, p53, Caspase 3, and Bax expressions were attenuated. Our findings unravel the immunosuppressive effects of hPDLSCs-CM and hPDLSCs-EMVs in EAE mice, and suggest simple alternative autologous source for patient-customized cell-free targeting treatment in MS patients.

Conditioned medium of periodontal ligament mesenchymal stem cells exert anti-inflammatory effects in lipopolysaccharide-activated mouse motoneurons

Conditioned medium derived from mesenchymal stem cells (MSCs) shows immunomodulatory and neuroprotective effects in preclinical models. Given the difficulty to harvest MSCs from bone marrow and adipose tissues, research has been focused to find alternative resources for MSCs, such as oral-derived tissues. Recently, we have demonstrated the protective effects of MSCs obtained from healthy human periodontal ligament tissue (hPDLSCs) in murine experimental autoimmune encephalomyelitis model. In the present in vitro study, we have investigated the immunomodulatory and neuroprotective effects of conditioned medium obtained from hPDLSCs of Relapsing Remitting- Multiple sclerosis (RR-MS) patients on NSC34 mouse motoneurons stimulated with lipopolysaccharide (LPS). Immunocytochemistry and western blotting were performed. Increased level of TLR4 and NFκB, and reduced level of IκB-α were observed in LPS-stimulated motoneurons, which were modulated by pre-conditioning with hPDLSC-conditioned medium. Inflammatory cytokines (TNF-α, IL-10), neuroprotective markers (Nestin, NFL 70, NGF, GAP43), and apoptotic markers (Bax, Bcl-2, p21) were modulated. Moreover, extracellular vesicles of hPDLSC-conditioned medium showed the presence of anti-inflammatory cytokines IL-10 and TGF-β. Our results demonstrate the immunosuppressive properties of hPDLSC-conditioned medium of RR-MS patients in motoneurons subjected to inflammation. Our findings warrant further preclinical and clinical studies to elucidate the autologous therapeutic efficacy of hPDLSC-conditioned medium in neurodegenerative diseases.

Characterization of mesenchymal stem cells in sheep naturally infected with scrapie

Mesenchymal stem cells (MSCs) can be infected with prions and have been proposed as in vitro cell-based models for prion replication. In addition, autologous MSCs are of interest for cell therapy in neurodegenerative diseases. To the best of our knowledge, the effect of prion diseases on the characteristics of these cells has never been investigated. Here, we analysed the properties of MSCs obtained from bone marrow (BM-MSCs) and peripheral blood (PB-MSCs) of sheep naturally infected with scrapie — a large mammal model for the study of prion diseases. After three passages of expansion, MSCs derived from scrapie animals displayed similar adipogenic, chondrogenic and osteogenic differentiation ability as cells from healthy controls, although a subtle decrease in the proliferation potential was observed. Exceptionally, mesenchymal markers such as CD29 were significantly upregulated at the transcript level compared with controls. Scrapie MSCs were able to transdifferentiate into neuron-like cells, but displayed lower levels of neurogenic markers at basal conditions, which could limit this potential .The expression levels of cellular prion protein (PrPC) were highly variable between cultures, and no significant differences were observed between control and scrapie-derived MSCs. However, during neurogenic differentiation the expression of PrPC was upregulated in MSCs. This characteristic could be useful for developing in vitro models for prion replication. Despite the infectivity reported for MSCs obtained from scrapie-infected mice and Creutzfeldt–Jakob disease patients, protein misfolding cyclic amplification did not detect PrPSc in BM- or PB-MSCs from scrapie-infected sheep, which limits their use for in vivo diagnosis for scrapie.

Stem cell therapy for amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the loss of motor neurons. Currently, no effective therapy is available to treat ALS, except for Riluzole, which has only limited clinical benefits. Stem-cell-based therapy has been intensively and extensively studied as a potential novel treatment strategy for ALS and has been shown to be effective, at least to some extent. In this article, we will review the current state of research on the use of stem cell therapy in the treatment of ALS and discuss the most promising stem cells for the treatment of ALS.

Plasma Derived From Human Umbilical Cord Blood Modulates Mitogen-Induced Proliferation of Mononuclear Cells Isolated From the Peripheral Blood of ALS Patients

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by degeneration of motor neurons in the spinal cord and brain. This disease clinically manifests as gradual muscular weakness and atrophy leading to paralysis and death by respiratory failure. While multiple interdependent factors may contribute to the pathogenesis of ALS, increasing evidence shows the possible presence of autoimmune mechanisms that promote disease progression. The potential use of plasma derived from human umbilical cord blood (hUCB) as a therapeutic tool is currently in its infancy. The hUCB plasma is rich in cytokines and growth factors that are required for growth and survival of cells during hematopoiesis. In this study, we investigated the effects of hUCB plasma on the mitogen-induced proliferation of mononuclear cells (MNCs) isolated from the peripheral blood of ALS patients and apoptotic activity by detection of caspase 3/7 expression of the isolated MNCs in vitro. Three distinct responses to phytohemagglutinin (PHA)-induced proliferation of MNCs were observed, which were independent of age, disease duration, and the ALS rating scale: Group I responded normally to PHA, Group II showed no response to PHA, while Group III showed a hyperactive response to PHA. hUCB plasma attenuated the hyperactive response (Group III) and potentiated the normal response in Group I ALS patients, but did not alter that of the nonresponders to PHA (Group II). The elevated activity of caspase 3/7 observed in the MNCs from ALS patients was significantly reduced by hUCB plasma treatment. Thus, study results showing different cell responses to mitogen suggest alteration in lymphocyte functionality in ALS patients that may be a sign of immune deficiency in the nonresponders and autoimmunity alterations in the hyperactive responders. The ability of hUCB plasma to modulate the mitogen cell response and reduce caspase activity suggests that the use of hUCB plasma alone, or with stem cells, may prove useful as a therapeutic in ALS patients.

Concise review: Stem cell therapies for amyotrophic lateral sclerosis: recent advances and prospects for the future

Amyotrophic lateral sclerosis (ALS) is a lethal disease involving the loss of motor neurons. Although the mechanisms responsible for motor neuron degeneration in ALS remain elusive, the development of stem cell-based therapies for the treatment of ALS has gained widespread support. Here, we review the types of stem cells being considered for therapeutic applications in ALS, and emphasize recent preclinical advances that provide supportive rationale for clinical translation. We also discuss early trials from around the world translating cellular therapies to ALS patients, and offer important considerations for future clinical trial design. Although clinical translation is still in its infancy, and additional insight into the mechanisms underlying therapeutic efficacy and the establishment of long-term safety are required, these studies represent an important first step toward the development of effective cellular therapies for the treatment of ALS.

Mesenchymal stem cell therapy for the treatment of amyotrophic lateral sclerosis: signals for hope?

Based on the distinctive cellular, molecular and immunomodulatory traits of mesenchymal stem cells (MSC), it has been postulated that these cells may play a critical role in regenerative medicine. In addition to the participation of MSC in the repair of mesodermal-derived tissues (bone, cartilage), robust data have suggested that MSC may also play a reparative role in conditions involving damage of cells of ectodermal origin. The above content has been supported by the capability of MSC to differentiate into neuron-like cells as well as by a competence to generate a ‘neuroprotective’ environment. In turn, several preclinical studies have put forward the concept that MSC therapy may represent an option for the treatment of several neurological disorders and injuries, including amyotrophic lateral sclerosis. We expect that the above foundations, which have inspired this review, may result in the founding of an effective and/or palliative therapy for amyotrophic lateral sclerosis.

Human mesenchymal stromal cell transplantation modulates neuroinflammatory milieu in a mouse model of amyotrophic lateral sclerosis

BACKGROUND AIMS

Mesenchymal stromal cells (MSCs), after intraparenchymal, intrathecal and endovenous administration, have been previously tested for cell therapy in amyotrophic lateral sclerosis in the SOD1 (superoxide dismutase 1) mouse. However, every administration route has specific pros and cons.

METHODS

We administrated human MSCs (hMSCs) in the cisterna lumbaris, which is easily accessible and could be used in outpatient surgery, in the SOD1 G93A mouse, at the earliest onset of symptoms. Control animals received saline injections. Motor behavior was checked starting from 2 months of age until the mice were killed. Animals were killed 2 weeks after transplantation; lumbar motoneurons were stereologically counted, astrocytes and microglia were analyzed and quantified after immunohistochemistry and cytokine expression was assayed by means of real-time polymerase chain reaction.

RESULTS

We provide evidence that this route of administration can exert strongly positive effects. Motoneuron death and motor decay were delayed, astrogliosis was reduced and microglial activation was modulated. In addition, hMSC transplantation prevented the downregulation of the anti-inflammatory interleukin-10, as well as that of vascular endothelial growth factor observed in saline-treated transgenic mice compared with wild type, and resulted in a dramatic increase in the expression of the anti-inflammatory interleukin-13.

CONCLUSIONS

Our results suggest that hMSCs, when intracisternally administered, can exert their paracrine potential, influencing the inflammatory response of the host.

The past, present and future of stem cell clinical trials for ALS

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disorder that is characterized by progressive degeneration of motor neurons in the cortex, brainstem and spinal cord. This leads to paralysis, respiratory insufficiency and death within an average of 3 to 5 years from disease onset. While the genetics of ALS are becoming more understood in familial cases, the mechanisms underlying disease pathology remain unclear and there are no effective treatment options. Without understanding what causes ALS it is difficult to design treatments. However, in recent years stem cell transplantation has emerged as a potential new therapy for ALS patients. While motor neuron replacement remains a focus of some studies trying to treat ALS with stem cells, there is more rationale for using stem cells as support cells for dying motor neurons as they are already connected to the muscle. This could be through reducing inflammation, releasing growth factors, and other potential less understood mechanisms. Prior to moving into patients, stringent pre-clinical studies are required that have at least some rationale and efficacy in animal models and good safety profiles. However, given our poor understanding of what causes ALS and whether stem cells may ameliorate symptoms, there should be a push to determine cell safety in pre-clinical models and then a quick translation to the clinic where patient trials will show if there is any efficacy. Here, we provide a critical review of current clinical trials using either mesenchymal or neural stem cells to treat ALS patients. Pre-clinical data leading to these trials, as well as those in development are also evaluated in terms of mechanisms of action, validity of conclusions and rationale for advancing stem cell treatment strategies for this devastating disorder.

Neural induction with neurogenin 1 enhances the therapeutic potential of mesenchymal stem cells in an amyotrophic lateral sclerosis mouse model

Amyotrophic lateral sclerosis (ALS) is characterized by progressive dysfunction and degeneration of motor neurons in the central nervous system (CNS). In the absence of effective drug treatments for ALS, stem cell treatment has emerged as a candidate therapy for this disease. To date, however, there is no consensus protocol that stipulates stem cell types, transplantation timing, or frequency. Using an ALS mouse model carrying a high copy number of a mutant human superoxide dismutase-1 (SOD1)(G93A) transgene, we investigated the effect of neural induction on the innate therapeutic potential of mesenchymal stem cells (MSCs) in relation to preclinical transplantation parameters. In our study, the expression of monocyte chemoattractant protein-1 (MCP-1) was elevated in the ALS mouse spinal cord. Neural induction of MSCs with neurogenin 1 (Ngn1) upregulated the expression level of the MCP-1 receptor, CCR2, and enhanced the migration activity toward MCP-1 in vitro. Ngn1-expressing MSCs (MSCs-Ngn1) showed a corresponding increase in tropism to the CNS after systemic transplantation in ALS mice. Notably, MSCs-Ngn1 delayed disease onset if transplanted during preonset ages,whereas unprocessed MSCs failed to do so. If transplanted near the onset ages, a single treatment with MSCs-Ngn1 was sufficient to enhance motor functions during the symptomatic period (15–17 weeks), whereas unprocessed MSCs required repeated transplantation to achieve similar levels of motor function improvement. Our data indicate that systemically transplanted MSCs-Ngn1 can migrate to the CNS and exert beneficial effects on host neural cells for an extended period of time through paracrine functions, suggesting a potential benefit of neural induction of transplanted MSCs in long-term treatment of ALS.

Transplantation of mesenchymal stem cells in ALS

Amyotrophic lateral sclerosis (ALS) is a devastating incurable, neurodegenerative disease that targets motor neurons (MNs) in the primary motor cortex, brainstem, and spinal cord, leading to muscle atrophy, paralysis, and death due to respiratory failure within 2-5 years. Currently, there is no cure for ALS. The development of a therapy that can support or restore MN function and attenuate toxicity in the spinal cord provides the most comprehensive approach for treating ALS. Mesenchymal stem cells might be suitable for cell therapy in ALS because of their immunomodulatory and protective properties. In this review, the authors discuss the major challenges to the translation of in vitro and animal studies of MSCs therapy in the clinical setting.

Transplantation of human adipose tissue-derived stem cells delays clinical onset and prolongs life span in ALS mouse model

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that selectively affects motor neurons in the cortex, brain stem, and spinal cord. The precise pathogenic mechanism remains unknown, and there is currently no effective therapy. We evaluated the therapeutic effects of human adipose tissue-derived stem cells (ASCs) in an animal model of ALS. Human abdominal subcutaneous fat tissues were obtained by simple liposuction from donors, and ASCs were isolated from the fat stromal vascular fraction. ASCs were found to differentiate into adipocytes, chondrocytes, osteocytes, and neurons. SOD1G93A ALS mice were divided into three groups: sham, intravenous (IV), and intracerebroventricular (ICV) groups. Human ASCs were transplanted in the ALS mice at 70 postnatal days before the appearance of clinical symptoms. Behavior of transplanted animals was assessed by rotarod test, paw grip endurance (PaGE), and reflex index. Mice in every group were sacrificed after 4 weeks posttransplantation. Transplanted ASCs were identified in the lumbar spinal cords with an antihuman mitochondria antibody and cell type-specific markers for neurons or astrocytes. Delayed onset of clinical symptoms (26 days) and extended survival of animals (24 days) were observed in ALS mice transplanted with ASCs via ICV route. ASCs were found to secrete high levels of neurotrophic factors such as NGF, BDNF, IGF-1, and VEGF. Reduction of apoptotic cell death by these factors was confirmed in cultured CNS cells and in the ALS spinal cord. These results indicate that transplantation of ASCs in ALS mice provides neuroprotective effects by production of cytokines/growth factors, delays disease progression, and prolongs the life span of ALS mice.

Mesenchymal stem/stromal cells: a new ''cells as drugs'' paradigm. Efficacy and critical aspects in cell therapy

Mesenchymal stem cells (MSCs) were first isolated more than 50 years ago from the bone marrow. Currently MSCs may also be isolated from several alternative sources and they have been used in more than a hundred clinical trials worldwide to treat a wide variety of diseases. The MSCs mechanism of action is undefined and currently under investigation. For in vivo purposes MSCs must be produced in compliance with good manufacturing practices and this has stimulated research on MSCs characterization and safety. The objective of this review is to describe recent developments regarding MSCs properties, physiological effects, delivery, clinical applications and possible side effects.

Characterization of the secretome of human tooth germ stem cells (hTGSCs) reveals neuro-protection by fine-tuning micro-environment

Bone-marrow-derived mesenchymal stem cells (MSCs) demonstrate neuro-protective effects in several disease models. By producing growth-factors, cytokines and chemokines, they promote survival of neurons in damaged brain areas. Alternative MSC sources, such as human tooth germ stem cells (hTGSCs), have been investigated for their neuro-protective properties. They ameliorate effects of neuro-toxic agents by paracrine mechanisms, however these secreted bio-active molecules are not yet characterized. Therefore, the current study aimed to provide a detailed analysis of the secretome of hTGSCs. Brain cells were exposed to various toxic materials, including Alzheimer's β-amyloid peptide (β-AP) and 6-hydroxy-dopamine (6-OHDA). When co-cultured with hTGSCs, the activity of a number of anti-oxidant enzymes (catalase, glutathione-s-transferase, glutathione-peroxidase, superoxide-dismutase) was increased and neuronal death/apoptosis was subsequently reduced. The composition of the secreted bio-active materials is influenced by various pre-existing factors such as oxygen and glucose deprivation and the age of cells (passage number). This report reveals for the first time that the neuro-protective secretome of hTGSCs and the micro-environment of cells have a mutual and dynamic impact on one another.

Cell therapy with autologous mesenchymal stem cells-how the disease process impacts clinical considerations

The prospective clinical use of multipotent mesenchymal stromal cells (MSCs) holds enormous promise for the treatment of a large number of degenerative and age-related diseases. In particular, autologous MSCs isolated from bone marrow (BM) are considered safe and have been extensively evaluated in clinical trials. Nevertheless, different efficacies have been reported, depending on the health status and age of the donor. In addition, the biological functions of BM-MSCs from patients with various diseases may be impaired. Furthermore, medical treatments such as long-term chemotherapy and immunomodulatory therapy may damage the BM microenvironment and affect the therapeutic potential of MSCs. Therefore, a number of practical problems must be addressed before autologous BM-MSCs can be widely applied with higher efficiency in patients. As such, this review focuses on various factors that directly influence the biological properties of BM-MSCs, and we discuss the possible mechanisms of these alterations.

Patient-derived stem cells: pathways to drug discovery for brain diseases

The concept of drug discovery through stem cell biology is based on technological developments whose genesis is now coincident. The first is automated cell microscopy with concurrent advances in image acquisition and analysis, known as high content screening (HCS). The second is patient-derived stem cells for modeling the cell biology of brain diseases. HCS has developed from the requirements of the pharmaceutical industry for high throughput assays to screen thousands of chemical compounds in the search for new drugs. HCS combines new fluorescent probes with automated microscopy and computational power to quantify the effects of compounds on cell functions. Stem cell biology has advanced greatly since the discovery of genetic reprograming of somatic cells into induced pluripotent stem cells (iPSCs). There is now a rush of papers describing their generation from patients with various diseases of the nervous system. Although the majority of these have been genetic diseases, iPSCs have been generated from patients with complex diseases (schizophrenia and sporadic Parkinson’s disease). Some genetic diseases are also modeled in embryonic stem cells (ESCs) generated from blastocysts rejected during in vitro fertilization. Neural stem cells have been isolated from post-mortem brain of Alzheimer’s patients and neural stem cells generated from biopsies of the olfactory organ of patients is another approach. These “olfactory neurosphere-derived” cells demonstrate robust disease-specific phenotypes in patients with schizophrenia and Parkinson’s disease. HCS is already in use to find small molecules for the generation and differentiation of ESCs and iPSCs. The challenges for using stem cells for drug discovery are to develop robust stem cell culture methods that meet the rigorous requirements for repeatable, consistent quantities of defined cell types at the industrial scale necessary for HCS.

Differentiation of CD133+ stem cells from amyotrophic lateral sclerosis patients into preneuron cells

Improvements in quality of life and life expectancy have been observed in amyotrophic lateral sclerosis (ALS) patients transplanted with CD133(+) stem cells into their frontal motor cortices. However, questions have emerged about the capacity of cells from these patients to engraft and differentiate into neurons. The objective of this work was to evaluate the in vitro capacity of CD133(+) stem cells from 13 ALS patients to differentiate into neuron lineage. Stem cells were obtained through leukapheresis and cultured in a control medium or a neuroinduction medium for 2-48 hours. Expression of neuronal genes was analyzed by reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemical techniques. Fluorescence microscopy demonstrated that CD133(+) stem cells from ALS patients incubated for 48 hours in a neuroinduction medium increased the detection of neuronal proteins such as nestin, β-tubulin III, neuronal-specific enolase, and glial fibrillary acidic protein. RT-PCR assays demonstrated an increase in the expression of β-tubulin III, nestin, Olig2, Islet-1, Hb9, and Nkx6.1. No correlation was found between age, sex, or ALS functional scale and the CD133(+) stem cell response to the neuroinduction medium. We conclude that CD133(+) stem cells from ALS patients, like the stem cells of healthy subjects, are capable of differentiating into preneuron cells.

Promise(s) of mesenchymal stem cells as an in vitro model system to depict pre-diabetic/diabetic milieu in WNIN/GR-Ob mutant rats

Background

Development of model systems have helped to a large extent, in bridging gap to understand the mechanism(s) of disease including diabetes. Interestingly, WNIN/GR-Ob rats (Mutants), established at National Centre for Laboratory Animals (NCLAS) of National Institute of Nutrition (NIN), form a suitable model system to study obesity with Type 2 diabetes (T2D) demonstrating several secondary complications (cataract, cardiovascular complications, infertility, nephropathy etc). The present study has been carried out to explore the potent application(s) of multipotent stem cells such as bone marrow mesenchymal stem cells (BM-MSCs), to portray features of pre-diabetic/T2D vis-à-vis featuring obesity, with impaired glucose tolerance (IGT), hyperinsulinemia (HI) and insulin resistance (IR) seen with Mutant rats akin to human situation.

Methodology/Principal Findings

Primary cultures of BM-MSCs (third passage) from Mutants, its lean littermate (Lean) and parental control (Control) were characterized for: proliferation markers, disease memory to mark obesity/T2D/HI/IR which included phased gene expression studies for adipogenic/pancreatic lineages, inflammatory markers and differentiation ability to form mature adipocytes/Insulin-like cellular aggregates (ILCAs). The data showed that BM-MSCs from Mutant demonstrated a state of disease memory, depicted by an upregulated expression of inflammatory markers (IL-6, TNFα); increased stem cell recruitment (Oct-4, Sox-2) and proliferation rates (CD90+/CD29+, PDA, ‘S’ phase of cell cycle by FACS and BrdU incorporation); accelerated preadipocyte induction (Dact-1, PPARγ2) with a quantitative increase in mature adipocyte formation (Leptin); ILCAs, which were non-responsive to high glucose did confer the Obese/T2D memory in Mutants. Further, these observations were in compliance with the anthropometric data.

Conclusions

Given the ease of accessibility and availability of MSCs, the present study form the basis to report for the first time, application of BM-MSCs as a feasible in vitro model system to portray the disease memory of pre-clinical/T2D with IR - a major metabolic disorder of global concern.

Olfactory ensheathing cell neurorestorotherapy for amyotrophic lateral sclerosis patients: benefits from multiple transplantations

Our previous series of studies have proven that olfactory ensheathing cell (OEC) transplantation appears to be able to slow the rate of clinical progression after OEC transplantation in the first 4 months and cell intracranial (key points for neural network restoration, KPNNR) and/or intraspinal (impaired segments) implants provide benefit for patients (including both the bulbar onset and limb onset subtypes) with amyotrophic lateral sclerosis (ALS). Here we report the results of cell therapy in patients with ALS on the basis of long-term observation following multiple transplants. From March of 2003 to January of 2010, 507 ALS patients received our cellular treatment. Among them, 42 patients underwent further OEC therapy by the route of KPNNR for two or more times (two times in 35 patients, three times in 5 patients, four times in 1 patient, and five times in 1 patient). The time intervals are 13.1 (6-60) months between the first therapy and the second one, 15.2 (8-24) months between the second therapy and the third one, 16 (6-26) months between the third therapy and the fourth one, and 9 months between the fourth therapy and the fifth time. All of the patients exhibited partial neurological functional recovery after each cell-based administration. Firstly, the scores of the ALS Functional Rating Scale (ALS-FRS) and ALS Norris Scale increased by 2.6 + 2.4 (0-8) and 4.9 + 5.2 (0-20) after the first treatment, 1.1 + 1.3 (0-5) and 2.3 + 2.9 (0-13) after the second treatment, 1.1 + 1.5 (0-4), and 3.4 + 6.9 (0-19) after the third treatment, 0.0 + 0.0 (0-0), and 2.5 + 3.5 (0-5) after the fourth treatment, and 1 point after the fifth cellular therapy, which were evaluated by independent neurologists. Secondly, the majority of patients have achieved improvement in electromyogram (EMG) assessments after the first, second, third, and fourth cell transplantation. After the first treatment, among the 42 patients, 36 (85.7%) patients' EMG test results improved, the remaining 6 (14.3%) patients' EMG results showed no remarkable change. After the second treatment, of the 42 patients, 30 (71.4%) patients' EMG results improved, 11 (26.2%) patients showed no remarkable change, and 1 (2.4%) patient became worse. After the third treatment, out of the 7 patients, 4 (57.1%) patients improved, while the remaining 3 (42.9%) patients showed no change. Thirdly, the patients have partially recovered their breathing ability as demonstrated by pulmonary functional tests. After the first treatment, 20 (47.6%) patients' pulmonary function ameliorated. After the second treatment, 18 (42.9%) patients' pulmonary function improved. After the third treatment, 2 (28.6%) patients recovered some pulmonary function. After the fourth and fifth treatment, patients' pulmonary function did not reveal significant change. The results show that multiple doses of cellular therapy definitely serve as a positive role in the treatment of ALS. This repeated and periodic cell-based therapy is strongly recommended for the patients, for better controlling this progressive deterioration disorder.

Stem cell therapy for the spinal cord

Injury and disease of the spinal cord are generally met with a poor prognosis. This poor prognosis is due not only to the characteristics of the diseases but also to our poor ability to deliver therapeutics to the spinal cord. The spinal cord is extremely sensitive to direct manipulation, and delivery of therapeutics has proven a challenge for both scientists and physicians. Recent advances in stem cell technologies have opened up a new avenue for the treatment of spinal cord disease and injury. Stem cells have proven beneficial in rodent models of spinal cord disease and injury. In these animal models, stem cells have been shown to produce their effect by the dual action of cell replacement and the trophic support of the factors secreted by these cells. In this review we look at the main clinical trials involving stem cell transplant into the spinal cord, focusing on motor neuron diseases and spinal cord injury. We will also discuss the major hurdles in optimizing stem cell delivery methods into the spinal cord. We shall examine current techniques such as functional magnetic resonance imaging guidance and cell labeling and will look at the current research striving to improve these techniques. With all caveats and future research taken into account, this is a very exciting time for stem cell transplant into the spinal cord. We are only beginning to realize the huge potential of stem cells in a central nervous system setting to provide cell replacement and trophic support. Many more trials will need to be undertaken before we can fully exploit the attributes of stem cells.

Investigation of Telomerase/Telomeres system in Bone Marrow Mesenchymal Stem Cells derived from IPF and RA-UIP

OBJECTIVE

Idiopathic Pulmonary Fibrosis and Rheumatoid Arthritis associated usual interstitial pneumonia seem to have the same poor outcome as there is not an effective treatment. The aim of the study is to explore the reparative ability of bone marrow mesenchymal stem cells by evaluating the system telomerase/telomeres and propose a novel therapeutic approach.

METHODS

BM-MSCs were studied in 6 IPF patients, 7 patients with RA-UIP and 6 healthy controls. We evaluated the telomere length as well as the mRNA expression of both components of telomerase (human telomerase reverse transcriptase, h-TERT and RNA template complementary to the telomeric loss DNA, h-TERC).

RESULTS

We found that BM-MSCs from IPF, RA-UIP cases do not present smaller telomere length than the controls (p = 0.170). There was no significant difference regarding the expression of both h-TERT and h-TERC genes between patients and healthy controls (p = 0.107 and p = 0.634 respectively).

CONCLUSIONS

We demonstrated same telomere length and telomerase expression in BM-MSCs of both IPF and RA-UIP which could explain similarities in pathogenesis and prognosis. Maintenance of telomere length in these cells could have future implication in cell replacement treatment with stem cells of these devastating lung disorders.

The functional deficiency of bone marrow mesenchymal stromal cells in ALS patients is proportional to disease progression rate

Amyotrophic lateral sclerosis (ALS) is caused by motor neuron death. The relationship between the prognosis of ALS patients and the function of their bone marrow mesenchymal stromal cells (BM-MSCs) is unclear. We designed this study to assess the correlation between the progression rate of the ALS Functional Rating Scale-revised version (ΔFS), which is reported to predict prognosis, and the pluripotency and trophic factor secreting capacity of ALS patients' BM-MSCs. We evaluated ΔFS in 23 ALS patients and isolated BM-MSCs from those patients and five healthy people. Levels of Nanog, Oct-4, and Nestin mRNA were examined to evaluate pluripotency, and levels of BDNF, ECGF1, bFGF-2, HGF, IGF-1, PGF, TGF-1β, SDF-1α, GDNF, VEGF, and ANG mRNA were examined to assess trophic factor secreting capacity. In addition, we measured the protein levels of Nanog, Oct-4, Nestin, SDF-1α, ANG, bFGF-2, VEGF, IGF-1, GDNF, and BDNF. mRNA levels of Nanog, Oct-4, ECGF1, bFGF-2, HGF, IGF-1, PGF, TGF-1β, SDF-1α, GDNF, VEGF, and ANG were negatively correlations with ΔFS. However, those of Nestin and BDNF were not significantly correlated with ΔFS. Similarly, Nanog, Oct-4, SDF-1α, ANG, bFGF-2, VEGF, IGF-1, and GDNF protein levels had a significant negative correlation with ΔFS. Results indicate that the pluripotency and trophic factor secreting capacity of the BM-MSCs of ALS patients are reduced in proportion to a poorer prognosis. We therefore suggest that healthy allogeneic BM-MSCs might be a better option for cell therapy in ALS patients.

Mesenchymal stromal cell transplantation in amyotrophic lateral sclerosis: a long-term safety study

BACKGROUND AIMS

Mesenchymal stem cells/marrow stromal cells (MSC) represent a promising tool for stem cell-based clinical trials in amyotrophic lateral sclerosis (ALS). We present the results of long-term monitoring of 19 ALS patients enrolled in two phase I clinical trials of autologous MSC transplantation.

METHODS

Nineteen patients (11 male and eightfemale) with ALS were enrolled in two consecutive phase I clinical trials. The patients were followed-up for 6-9 months and then treated with autologous MSC isolated from bone marrow and implanted into the dorsal spinal cord with a surgical procedure. The patients were monitored regularly before and after transplantation with clinical, psychological and neuroradiologic assessments every 3 months, at the tertiary referral ALS center in Novara (Italy), until death.

RESULTS

Follow-up brain magnetic resonance imaging (MRI) revealed no structural changes (including tumor formation) relative to the baseline throughout the follow-up. There was no deterioration in the psychosocial status and all patients coped well. No clear clinical benefits were detected in these patients but the recruitment and selection of appropriate patients into larger trials will be needed to test the efficacy of the treatment.

CONCLUSIONS

This study is the first to show the safety of MSC transplantation in the central nervous system during a follow-up of nearly 9 years, and is in support of applying MSC-based cellular clinical trials to neurodegenerative disorders.

Intracellular reactive oxygen species are required for directional migration of resident and bone marrow-derived hepatic pro-fibrogenic cells

BACKGROUND & AIMS

Liver fibrogenesis is sustained by myofibroblast-like cells originating from hepatic stellate cells (HSC/MFs), portal fibroblasts or bone marrow-derived cells, including mesenchymal stem cells (MSCs). Herein, we investigated the mechanistic role of intracellular generation of reactive oxygen species (ROS) and redox-sensitive signal transduction pathways in mediating chemotaxis, a critical profibrogenic response for human HSC/MFs and for MSC potentially engrafting chronically injured liver.

METHODS

Intracellular generation of ROS and signal transduction pathways were evaluated by integrating morphological and molecular biology techniques. Chemokinesis and chemotaxis were evaluated by wound healing assay and modified Boyden's chamber assay, respectively. Additional in vivo evidence was obtained in human specimens from HCV-related cirrhosis.

RESULTS

Human MSCs and HSC/MFs migrate in response to a panel of polypeptide chemoattractants and extracellularly generated superoxide anion. All polypeptides induced a NADPH-oxidase-dependent intracellular rise in ROS, resulting in activation of ERK1/2 and JNK1/2. Moreover, menadione or 2,3-dimethoxy-1,4-naphthoquinone, which generate intracellular superoxide anion or hydrogen peroxide, respectively, induced ERK1/2 and JNK1/2 activation and migration. JNK1 activation was predominant for migration as shown by specific silencing. Finally, activation of ERK1/2 and JNK1/2 was found in extracts obtained from HSC/MFs during the course of an oxidative stress-mediated model of liver injury and phosphorylated JNK1/2 isoforms were detected in α-smooth muscle actin-positive myofibroblasts lining fibrotic septa in human cirrhotic livers.

CONCLUSIONS

Intracellular generation of ROS, through activation of specific signaling pathways, is a critical event for directional migration of HSC/MFs and MSCs.

Olfactory ensheathing cell transplantation into spinal cord prolongs the survival of mutant SOD1(G93A) ALS rats through neuroprotection and remyelination

Amyotrophic lateral sclerosis (ALS) is a progressively fatal, incurable, neurodegenerative disorder. In this study, we investigated whether olfactory ensheathing cells (OEC) transplantation could provide protection to motor neurons and enable remyelination in mutant SOD1(G93A) transgenic rats with ALS. Seventy-two rats were divided into four groups: SOD1(G93A) rats (n = 20); medium+SOD1(G93A) rats (n = 20); OECs+SOD1(G93A) rats (n = 24); and another eight wild-type rats were used as controls. About 5 μL (1 × 10(5)) OECs in DF12 medium was injected into the dorsal funiculus of the thoracic spinal cord at a predetermined depth. Survival analysis revealed a significant increase in the survival time in OEC+SOD1(G93A) rats. Body weight records and inclined board test showed a significant difference between OEC+SOD1(G93A) and SOD1(G93A) from the onset at 7 days to 11 days (P < 0.05). Four weeks following transplantation, motor neuron counts in the ventral horn of the spinal cord noted a significant motor neuron loss in SOD1(G93A) rats when compared with wild-type rats (P < 0.001), and much less neuronal loss and collapse was noted in OEC+SOD1(G93A) rats when compared with SOD1(G93A) rats(P < 0.001); immunohistochemistry and Western blot analysis of choline acetyltransferase supported the motor neuron count. Images of confocal microscope indicated that the transplanted OECs had survived for more than 4 weeks and migrated 4.2 mm through the spinal cord. Evidence of remyelination of transplanted OEC was captured with triple fluorescence labeling of green fluorescent protein, neurofilament, and myelin basic protein and was further confirmed by Western blot analysis of MPB. In conclusion, the transplanted OECs could serve as a source of neuroprotection and remyelination to modify the ALS microenvironment.

Mesenchymal stem cells and potential applications in treating ocular disease

Mesenchymal stem cells (MSCs) are remarkable in stem cell biology. Not only do they have significant tissue regeneration potential, but more recently their paracrine effects (either innate or through genetic augmentation) have become increasingly recognized as useful therapeutic approaches. In particular, clinical roles for MSC therapy in neuroprotection and immune suppression are likely to emerge. These therapeutic effects will be particularly advantageous in work on neurological tissues, because MSC-based molecular therapy could overcome some of the difficulties of long-term drug delivery to tissues, such as the eye, which are relatively inaccessible to systemic delivery (for example due to the blood retina barrier). MSC therapy is, therefore, poised for significant impact in ocular molecular therapeutics, particularly for chronic diseases, such as retinal degeneration, glaucoma, and uveitis. Other molecular and tissue regeneration effects of MSCs are also likely to have impact in the management of ocular surface disease and oculoplastics.

New therapeutic targets for amyotrophic lateral sclerosis

INTRODUCTION

Amyotrophic lateral sclerosis (ALS) is one of the most devastating neurological disorders, affecting approximately half a million people worldwide. Currently there is no cure or prevention for ALS. Although ALS is a rare condition, it places a tremendous socioeconomic burden on patients, family members, caregivers and health systems.

AREAS COVERED

The review examines the mechanisms that may contribute to motor neuron degeneration in ALS, among which oxidative damage, glutatamate excitoxicity, mitochondrial dysfunction, impaired axonal transport, apoptotic cell death, growth factor deficiency, glial cell pathology and abnormal RNA metabolism are potential targets for ALS treatment. The article provides an overview of clinical trials performed to date in attempts to treat ALS with regard to molecular mechanisms and pathways they act on. It also discusses new trials based on recently developed molecular biology techniques.

EXPERT OPINION

Despite significant effectiveness of several potential therapeutics observed in preclinical trials, the results were not translatable to patients with ALS. The development of effective treatments of ALS strictly depends on understanding the primary cause of the disease. This goal will only be achieved when we identify the trigger point for motor neuron death in ALS.

Stem cell research in cell transplantation: sources, geopolitical influence, and transplantation

If the rapidly progressing field of stem cell research reaches its full potential, successful treatments and enhanced understanding of many diseases are the likely results. However, the full potential of stem cell science will only be reached if all possible avenues can be explored and on a worldwide scale. Until 2009, the US had a highly restrictive policy on obtaining cells from human embryos and fetal tissue, a policy that pushed research toward the use of adult-derived cells. Currently, US policy is still in flux, and retrospective analysis does show the US lagging behind the rest of the world in the proportional increase in embryonic/fetal stem cell research. The majority of US studies being on either a limited number of cell lines, or on cells derived elsewhere (or funded by other sources than Federal) rather than on freshly isolated embryonic or fetal material. Neural, mesenchymal, and the mixed stem cell mononuclear fraction are the most commonly investigated types, which can generally be classified as adult-derived stem cells, although roughly half of the neural stem cells are fetal derived. Other types, such as embryonic and fat-derived stem cells, are increasing in their prominence, suggesting that new types of stem cells are still being pursued. Sixty percent of the reported stem cell studies involved transplantation, of which over three quarters were allogeneic transplants. A high proportion of the cardiovascular systems articles were on allogeneic transplants in a number of different species, including several autologous studies. A number of pharmaceutical grade stem cell products have also recently been tested and reported on. Stem cell research shows considerable promise for the treatment of a number of disorders, some of which have entered clinical trials; over the next few years it will be interesting to see how these treatments progress in the clinic.

Characterization of in vitro expanded bone marrow-derived mesenchymal stem cells from patients with multiple sclerosis

Recent studies have investigated the potential of autologous bone marrow-derived mesenchymal stem cells (MSCs) as a therapy for multiple sclerosis. Whether MSCs from individuals with multiple sclerosis are functionally and/or phenotypically abnormal has received less attention. Through our Phase I clinical trial, SIAMMS, we were able to isolate and characterize MSCs from individuals with multiple sclerosis. The objective of the study was to demonstrate that MSCs from individuals with multiple sclerosis show no significant differences from MSCs derived from individuals without multiple sclerosis. MSCs were isolated from bone marrow aspirates from four SIAMMS participants. We were also able to isolate MSCs from bone marrow obtained during a total hip replacement operation on an individual with multiple sclerosis. Control MSCs were isolated from bone marrow acquired during total hip replacement operations on five individuals without MS. MSCs were characterized using standard criteria: plastic adherence, differentiation along adipogenic/osteogenic/chondrogenic lineages, and expression of specific cell surface antigens. We also determined their proliferation potential. MSCs from individuals with multiple sclerosis and individuals without multiple sclerosis were similar in proliferation, differentiation potential and cell surface antigen expression. This has relevance to scientific studies investigating the therapeutic potential of autologous MSCs which primarily utilize MSCs from individuals without multiple sclerosis, and relevance to clinical studies extrapolating from these scientific findings.