Autologous hematopoietic stem cell transplantation suppresses Gd-enhanced MRI activity in MS

Cell-based experimental strategies for myelin repair in multiple sclerosis

Multiple sclerosis (MS) is an autoimmune demyelinating disorder of the central nervous system (CNS), diagnosed at a mean age of 32 years. CNS glia are crucial players in the onset of MS, primarily involving astrocytes and microglia that can cause/allow massive oligodendroglial cells death, without immune cell infiltration. Current therapeutic approaches are aimed at modulating inflammatory reactions during relapsing episodes, but lack the ability to induce very significant repair mechanisms. In this review article, different experimental approaches based mainly on the application of different cell types as therapeutic strategies applied for the induction of myelin repair and/or the amelioration of the disease are discussed. Regarding this issue, different cell sources were applied in various experimental models of MS, with different results, both in significant improvements in remyelination and the reduction of neuroinflammation and glial activation, or in neuroprotection. All cell types tested have advantages and disadvantages, which makes it difficult to choose a better option for therapeutic application in MS. New strategies combining cell-based treatment with other applications would result in further improvements and would be good candidates for MS cell therapy and myelin repair.

Stem Cell Therapy in Neuroimmunological Diseases and Its Potential Neuroimmunological Complications

Background: Since the 1990s, transplantations of hematopoietic and mesenchymal stem cells (HSCT and MSCT) and dendritic cell (DCT) have been investigated for the treatment of neurological autoimmune disorders (NADs). With the growing number of transplanted patients, awareness of neuroimmunolgical complications has increased. Therefore, an overview of SCT for the most common NADs and reports of secondary immunity after SCT is provided. Methods: For this narrative review, a literature search of the PubMed database was performed. A total of 86 articles reporting on different SCTs in NADs and 61 articles dealing with immune-mediated neurological complications after SCT were included. For multiple sclerosis (MS), only registered trials and phase I/II or II studies were considered, whereas all available articles on other disorders were included. The different transplantation procedures and efficacy and safety data are presented. Results: In MS patients, beneficial effects of HSCT, MSCT, and DCT with a decrease in disability and stabilization of disease activity have been reported. These effects were also shown in other NADs mainly in case reports. In seven of 132 reported patients with immune-mediated neurological complications, the outcome was fatal. Conclusions: Phase III trials are ongoing for MS, but the role of SCT in other NADs is currently limited to refractory patients due to occasional serious complications.

Cell-based drug delivery systems and their in vivo fate

Cell-based drug delivery systems (DDSs) have received attention recently because of their unique biological properties and self-powered functions, such as excellent biocompatibility, low immunogenicity, long circulation time, tissue-homingcharacteristics, and ability to cross biological barriers. A variety of cells, including erythrocytes, stem cells, and lymphocytes, have been explored as functional vectors for the loading and delivery of various therapeutic payloads (e.g., small-molecule and nucleic acid drugs) for subsequent disease treatment. These cell-based DDSs have their own unique in vivo fates, which are attributed to various factors, including their biological properties and functions, the loaded drugs and loading process, physiological and pathological circumstances, and the body's response to these carrier cells, which result in differences in drug delivery efficiency and therapeutic effect. In this review, we summarize the main cell-based DDSs and their biological properties and functions, applications in drug delivery and disease treatment, and in vivo fate and influencing factors. We envision that the unique biological properties, combined with continuing research, will enable development of cell-based DDSs as friendly drug vectors for the safe, effective, and even personalized treatment of diseases.

The current standing of autologous haematopoietic stem cell transplantation for the treatment of multiple sclerosis

Autologous haematopoietic stem cell transplantation (aHSCT) is gaining traction as a valuable treatment option for patients affected by severe multiple sclerosis (MS), particularly the relapsing–remitting form. We describe the current literature in terms of clinical trials, observational and retrospective studies, as well as immune reconstitution following transplantation, with a focus on the conditioning regimens used for transplantation. The evidence base predominantly consists of non-randomised, uncontrolled clinical trials or data from retrospective or observational cohorts, i.e. very few randomised or controlled trials. Most often, intermediate-intensity conditioning regimens are used, with promising results from both myeloablative and lymphoablative strategies, as well as from regimens that are low and high intensity. Efficacy of transplantation, which is likely secondary to immune reconstitution and restored immune tolerance, is, therefore, not clearly dependent on the intensity of the conditioning regimen. However, the conditioning regimen may well influence the immune response to transplantation. Heterogeneity of conditioning regimens among studies hinders synthesis of the articles assessing post-aHSCT immune system changes. Factors associated with better outcomes were lower Kurtzke Expanded Disability Status Scale, relapsing–remitting MS, younger age, and shorter disease duration at baseline, which supports the guidance for patient selection proposed by the European Society for Blood and Marrow Transplantation. Interestingly, promising outcomes were described for patients with secondary progressive MS by some studies, which may be worth taking into account when considering treatment options for patients with active, progressive disease. Of note, a significant proportion of patients develop autoimmune disease following transplantation, with alemtuzumab-containing regimens associated with the highest incidence.

Immune Reconstitution Following Autologous Hematopoietic Stem Cell Transplantation for Multiple Sclerosis: A Review on Behalf of the EBMT Autoimmune Diseases Working Party

Multiple sclerosis (MS) is a central nervous system (CNS) disorder, which is mediated by an abnormal immune response coordinated by T and B cells resulting in areas of inflammation, demyelination, and axonal loss. Disease-modifying treatments (DMTs) are available to dampen the inflammatory aggression but are ineffective in many patients. Autologous hematopoietic stem cell transplantation (HSCT) has been used as treatment in patients with a highly active disease, achieving a long-term clinical remission in most. The rationale of the intervention is to eradicate inflammatory autoreactive cells with lympho-ablative regimens and restore immune tolerance. Immunological studies have demonstrated that autologous HSCT induces a renewal of TCR repertoires, resurgence of immune regulatory cells, and depletion of proinflammatory T cell subsets, suggesting a "resetting" of immunological memory. Although our understanding of the clinical and immunological effects of autologous HSCT has progressed, further work is required to characterize the mechanisms that underlie treatment efficacy. Considering that memory B cells are disease-promoting and stem-like T cells are multipotent progenitors involved in self-regeneration of central and effector memory cells, investigating the reconstitution of B cell compartment and stem and effector subsets of immunological memory following autologous HSCT could elucidate those mechanisms. Since all subjects need to be optimally protected from vaccine-preventable diseases (including COVID-19), there is a need to ensure that vaccination in subjects undergoing HSCT is effective and safe. Additionally, the study of vaccination in HSCT-treated subjects as a means of evaluating immune responses could further distinguish broad immunosuppression from immune resetting.

The use of patient-specific stem cells in different autoimmune diseases

Autoimmune diseases are developed when the immune system mistakenly attacks the body’s cells. These inflammatory disorders can be inherited or triggered by external forces, such as type 1 diabetes, which is caused by the immune system's destruction of pancreatic beta cells. So far, stem cells such as hESC and iPSC have been used to treat autoimmune disorders such as type 1 diabetes, rheumatoid arthritis (RA), multiple sclerosis (MS), and systemic lupus erythematosus (SLE), although these procedures have certain ethical concerns. On the other hand, bone marrow-derived mesenchymal stem cells (BM-MSC) are thought to be the best source of stem cells. Later, it was shown that mesenchymal stem cells produced from autologous adipose tissues have a great potential for producing huge volumes of stem cells. In-vitro and in-vivo investigations using autologous hematopoietic stem cells and autologous mesenchymal stem cells have been carried out on various rodent and human models, while clinical trials for inflammatory diseases such as multiple sclerosis and diabetes mellitus have yielded promising results. We attempted to summarise the usage of diverse stem cells in the therapy of various autoimmune disorders in this review. Shortly, we expect that the use of autologous stem cells will provide a new perspective on the treatment of autoimmune disorders.

Autologous Haematopoietic Stem Cell Transplantation in Active Multiple Sclerosis: a Real-world Case Series

OBJECTIVE

to examine outcomes in people with multiple sclerosis (PwMS) treated with autologous hematopoietic stem cell transplantation (AHSCT) in a real-world setting.

METHODS

retrospective cohort study on PwMS treated with AHSCT at two centers in London, UK, consecutively between 2012 and 2019 who had ≥ 6 months of follow-up or died at any time. Primary outcomes were survival free of MS relapses, MRI new lesions and worsening of expanded disability status scale (EDSS). Adverse events rates were also examined.

RESULTS

the cohort includes 120 PwMS; 52% had progressive MS (primary or secondary) and 48% had relapsing-remitting MS (RRMS). At baseline, the median expanded disability status scale (EDSS) was 6.0; 90% of the evaluable cases showed MRI activity in the 12 months preceding AHSCT. Median follow-up after AHSCT was 21 months (range 6-85). MS relapse-free survival was 93% at 2 years and 87% at 4 years after AHSCT. No new MRI lesions were detected in 90% of subjects at 2 years and 85% at 4 years. EDSS progression-free survival (PFS) was 75% at 2 years and 65% at 4 years. EBV reactivation and monoclonal paraproteinemia were associated with worse PFS. There were 3 transplant-related deaths within 100 days (2.5%), all following fluid overload and cardiac or respiratory failure.

CONCLUSIONS

efficacy outcomes of AHSCT in this real-world cohort are similar to those reported in more stringently selected clinical trial populations, although the risks may be higher.

CLASSIFICATION OF EVIDENCE

this study is rated Class IV because of the uncontrolled, open-label design.

Gene and cell therapy and nanomedicine for the treatment of multiple sclerosis: bibliometric analysis and systematic review of clinical outcomes

INTRODUCTION

Continuous improvement in cellular and molecular biology has led to the development of diverse advanced therapies. These include cell therapy and gene therapy, among others. Nanomedicine can also be used for therapeutic purposes.

AREAS COVERED

The author carried out a bibliometric analysis to find out about the biomedical literature in these therapies applied to multiple sclerosis (MS) and its chronological evolution, from a quantitative and qualitative point of view. After this, articles which were identified as clinical trials were retrieved full-text and examined for further evaluation of their evidence-based level according to the CASP scale. In the bibliometric analysis the authors retrieved 2,791 studies, from which 2,405 were about cell therapy, 194 about gene therapy and 192 about nanomedicine; scientific production in these areas has been progressive and growing in terms of quantity and quality. In the systematic review 39 trials were retrieved, all of them about cell therapy, which had relevant sample sizes. The average of scientific-quality was good or very good (about 9/11 points).

EXPERT OPINION

There is a class I evidence supporting the effectiveness of cell therapy as safe therapeutic option in multiple sclerosis with health benefits in the medium and long term.

Haematopoietic Stem Cell Transplantation for Multiple Sclerosis: Current Status

Autologous haematopoietic stem cell transplantation (AHSCT) is a treatment option for aggressive forms of multiple sclerosis (MS) that has been derived from haematological indications and repurposed for treatment of refractory autoimmune diseases. In the present review, a search for clinical studies on AHSCT was performed on the PubMed website and ClinicalTrials.gov databases. Papers were selected according to the following criteria: text written in English language, publication date between 2014 and August 2019, and reports including more than five patients. Prospective randomised and uncontrolled trials and retrospective case series were reviewed to examine the safety and efficacy of the procedure. Treatment protocols, pathological data and economic aspects of AHSCT were also succinctly covered. Growing evidence suggests that long-term suppression of inflammatory activity with stabilization or improvement of disability can be achieved in a high proportion of properly selected patients. More sophisticated outcome measures recently adopted, including effect on brain atrophy and disease biomarkers, are giving further insight into the effectiveness of transplant. The risks of the procedure have decreased to levels that can be considered acceptable for treatment of individuals with aggressive forms of MS. Careful selection of patients with an expected good benefit/risk profile, which is maximal when AHSCT is performed in early phases of the disease, and the expertise of transplant centres are critical to the success of treatment. Higher efficacy of AHSCT than with conventional treatments has recently been demonstrated by one randomised trial and further evidence is awaited from ongoing and planned trials comparing AHSCT with the most effective disease-modifying therapeutic agents.

[Indications and follow-up for autologous hematopoietic stem cell transplantation in multiple sclerosis: Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) in association with the Francophone Society of Multiple Sclerosis]

The Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) organized the 8th allogeneic hematopoietic stem cell transplantation clinical practices harmonization workshop series in September 2017 in Lille, France. In this article we give the indications of autologous stem cell transplantation in multiple sclerosis as well as recommendations regarding post-transplant follow-up of patients under the hospice of the SFGM-TC and the Francophone Society of Multiple Sclerosis.

Intense immunosuppression followed by autologous haematopoietic stem cell transplantation as a therapeutic strategy in aggressive forms of multiple sclerosis

In the majority of relapsing multiple sclerosis patients, the disease can be quite easily controlled by already available, approved therapies. There are, however, some aggressive cases who continue to have clinical and magnetic resonance imaging (MRI) activity in spite of the treatment. These are the cases who may now receive benefit from intense immunosuppression followed by autologous haematopoietic stem cell transplantation (aHSCT). In this review, we describe the method and the rationale of aHSCT, the more recently published studies that demonstrate its efficacy in selected multiple sclerosis cases, the problems related to safety and the transplant-related mortality risk of the procedure. A description of the ideal patient who can take advantage of aHSCT is outlined and, finally, the ongoing studies which are near to completion or are close to starting are briefly reported.

Autologous haematopoietic stem cell transplantation for treatment of multiple sclerosis

Autologous haematopoietic stem cell transplantation (AHSCT) is a multistep procedure that enables destruction of the immune system and its reconstitution from haematopoietic stem cells. Originally developed for the treatment of haematological malignancies, the procedure has been adapted for the treatment of severe immune-mediated disorders. Results from ∼20 years of research make a compelling case for selective use of AHSCT in patients with highly active multiple sclerosis (MS), and for controlled trials. Immunological studies support the notion that AHSCT causes qualitative immune resetting, and have provided insight into the mechanisms that might underlie the powerful treatment effects that last well beyond recovery of immune cell numbers. Indeed, studies have demonstrated that AHSCT can entirely suppress MS disease activity for 4-5 years in 70-80% of patients, a rate that is higher than those achieved with any other therapies for MS. Treatment-related mortality, which was 3.6% in studies before 2005, has decreased to 0.3% in studies since 2005. Current evidence indicates that the patients who are most likely to benefit from and tolerate AHSCT are young, ambulatory and have inflammatory MS activity. Clinical trials are required to rigorously test the efficacy, safety and cost-effectiveness of AHSCT against highly active MS drugs.

Cell Therapy for Multiple Sclerosis

Cell therapy is considered a promising potential treatment for multiple sclerosis, perhaps particularly for the progressive form of the disease for which there are currently no useful treatments. Over the past two decades or more, much progress has been made in understanding the biology of MS and in the experimental development of cell therapy for this disease. Three quite distinct forms of cell therapy are currently being pursued. The first seeks to use stem cells to replace damaged myelin-forming oligodendrocytes within the CNS; the second aims, in effect, to replace the individual's misfunctioning immune system, making use of haematopoietic stem cells; and the third seeks to utilise endogenous stem cell populations by mobilisation with or without in vitro expansion, exploiting their various reparative and neuroprotective properties. In this article we review progress in these three separate areas, summarising the experimental background and clinical progress thus far made.

Long-term systemic lupus erythematosus disease control after allogeneic bone marrow transplantation

Systemic lupus erythematosus (SLE), a disorder of the immune system, is potentially curable by allogeneic bone marrow transplantation (alloBMT). Until recently, alloBMT was limited by donor availability and toxicity. Reduced intensity conditioning (RIC) combined with post-transplantation cyclophosphamide (PTCy) has improved the availability and safety of alloBMT permitting its exploration in severe-refractory autoimmune illnesses. We report the six-year follow-up of a young female whose refractory SLE-associated nephrosis resolved after RIC alloBMT with PTCy.

Autologous stem cell transplantation as rescue therapy in malignant forms of multiple sclerosis

Malignant forms of multiple sclerosis (MS) represent a limited group of very aggressive demyelinating diseases, which rapidly progress to severe disability leading often to life-threatening conditions. On these clinical entities, currently available therapies for MS are not very effective. Recently, it has been demonstrated that intense immunosuppression followed by autologous stem cell transplantation (ASCT) can affect the clinical course of individuals with severe MS and completely abrogate the inflammatory activity detected by magnetic resonance imaging (MRI). We report on the treatment with intense immune ablation followed by ASCT of three patients with malignant MS whose clinical course indicated a dramatically poor prognosis. This procedure succeeded in halting the rapidly worsening course of disease. The effect was long lasting, as demonstrated by a sustained efficacy over a two-year period in two subjects and 12 months in the third case. In addition, a striking effect on inflammation-related MRI findings was obtained. These results support a role for intense immunosuppression followed by ASCT as treatment in rapidly evolving malignant MS cases unresponsive to conventional therapies.

Discordant functional and inflammatory parameters in multiple sclerosis patients after autologous haematopoietic stem cell transplantation

This article describes outcomes in four patients with advanced multiple sclerosis up to two years after autologous haematopoietic stem cell transplantation using a total-body irradiation-based preparative regimen. MRI and C SF analyses demonstrated clear suppression of the inflammatory processes. The results demonstrate however, a dissociation of inflammation parameters and functional disability findings raising questions about optimal future stem cell transplantatio n strategies for this disease.

Current Science of Regenerative Medicine with Stem Cells

Regenerative medicine with stem cells holds great hope for the treatment of degenerative disease. The medical potential of embryonic stem cells remains relatively untapped at this point, and significant scientific hurdles remain to be overcome before these cells might be considered safe and effective for uses in patients. Meanwhile, adult stem cells have begun to show significant capabilities of their own in repair of damaged tissues, in both animal models and early patient trials.

Low intensity lympho-ablative regimen followed by autologous hematopoietic stem cell transplantation in severe forms of multiple sclerosis: A MRI-based clinical study

BACKGROUND

Autologous hematopoietic stem cell transplantation (AHSCT) has been successfully used to treat aggressive forms of multiple sclerosis (MS) that are unresponsive to approved therapies. In the last years, in view of the risk of mortality related to the procedure, the utilization of low-intensity conditioning regimens has been considered.

OBJECTIVE

To report magnetic resonance imaging (MRI) and clinical data in a small cohort of patients treated with a low-intensity lympho-ablative regimen, followed by AHSCT.

METHODS

Seven patients affected by relapsing-remitting MS (RRMS) underwent AHSCT, with cyclophosphamide 120 mg/kg in 2 days as the conditioning regimen; and were then followed with serial MRI evaluations until 36 months, with clinical evaluations until 60 months.

RESULTS

The mean number of gadolinium (Gd)-enhancing lesions significantly decreased after treatment, but a complete suppression of inflammatory activity was not obtained. No deaths occurred, but every patient developed adverse events, although not severe. After 5 years of follow-up, two patients remained stable, one patient markedly improved and four patients had a mild progression of the disease. Only one patient experienced a relapse after treatment.

CONCLUSION

A low-intensity conditioning regimen with AHSCT has a profound effect on MRI inflammation and relapses, but is not able to completely abrogate MRI activity and disease progression of aggressive RRMS.

Comparison of neurophysiological and MRI findings of patients with multiple sclerosis using oligoclonal band technique

Background

The correlation of oligoclonal bands (OCBs) and intrathecal IgG synthesis are not yet clear in multiple sclerosis (MS).

Purpose

In this study, we investigated the OCB situation and IgG index, cranial and cervical magnetic resonance imaging (MRI) findings and also compared visual evoked potentials (VEP) and somatosensorial evoked potentials (SEP) in order to better understand the OCB pattern and pathogenesis.

Methods

Retrospective study included 40 patients (19 male, 21 female, mean age 29 ± 4,24) with precise MS diagnosis according to McDonald criteria.

Result

Sixteen of the patients were OCB negative, and 24 patients were positive. The different between the OCB situation and number of plaques in cranial and cervical MRI, atrophy, oedema and contrast material retention were insignificant. The different between the OCB situation and VEP and SEP were insignificant.

Conclusion

These laboratory findings are all specific, all developing via independent mechanisms and are not related to each other during the silence periods of patients.

Multiple sclerosis and cancer: when two wrongs make a right?

INTRODUCTION

Current treatments for multiple sclerosis (MS) remain partially successful, with certain patients remaining treatment resistant. A recent treatment, known as 'immunoablation' has been used in severe cases of adult MS with promising results. However, due to its high risk and reservation for severe or refractory cases, its full potential remains unknown.

METHODS

We report the case of MM, a 14-year-old boy diagnosed with MS and a concurrent diagnosis of Hodgkin's lymphoma.

RESULTS

After receiving aggressive chemotherapy (immunoablation) for Hodgkin's lymphoma, MM's MS symptoms appear to have remitted, and he has remained progression- and disease activity-free for over six years.

DISCUSSION

This case study will focus on MM's cognitive and behavioural development over this time, but will also discuss treatment implications raised by this rare case.

The influence of disease duration, clinical course, and immunosuppressive therapy on the synthesis of intrathecal oligoclonal IgG bands in multiple sclerosis

We investigated the impact of disease duration, clinical course and immunosuppressive therapy on intrathecal IgG synthesis in multiple sclerosis (MS). Cerebrospinal fluid (CSF) was obtained twice, 8-10 years apart, from 20 MS patients and 26 healthy controls, and from 22 MS patients before and after two years of mitoxantrone treatment. The oligoclonal IgG band patterns changed in 15 patients at long-term follow-up, but were only influenced in 4 patients by mitoxantrone therapy. The CSF B-cell-regulating chemokine CXCL13 correlated with intrathecal IgG production suggesting a B-cell-dependence of intrathecal IgG synthesis in MS.

Diminished Th17 (not Th1) responses underlie multiple sclerosis disease abrogation after hematopoietic stem cell transplantation

OBJECTIVE

To define changes in phenotype and functional responses of reconstituting T cells in patients with aggressive multiple sclerosis (MS) treated with ablative chemotherapy and autologous hematopoietic stem cell transplantation (HSCT).

METHODS

Clinical and brain magnetic resonance imaging measures of disease activity were monitored serially in patients participating in the Canadian MS HSCT Study. Reconstitution kinetics of immune-cell subsets were determined by flow cytometry, whereas thymic function was assessed using T-cell receptor excision circle analyses as well as flow cytometry measurements of CD31+ recent thymic emigrants (RTEs). Functional assays were performed to track central nervous system-autoreactive antigen-specific T-cell responses, and the relative capacity to generate Th1, Th17, or Th1/17 T-cell responses.

RESULTS

Complete abrogation of new clinical relapses and new focal inflammatory brain lesions throughout the 2 years of immune monitoring following treatment was associated with sustained decrease in naive T cells, in spite of restoration of both thymic function and release of RTEs during reconstitution. Re-emergence as well as in vivo expansion of autoreactive T cells to multiple myelin targets was evident in all patients studied. The reconstituted myelin-specific T cells exhibited the same Th1 and Th2 responses as preablation myelin-reactive T cells. In contrast, the post-therapy T-cell repertoire exhibited a significantly diminished capacity for Th17 responses.

INTERPRETATION

Our results indicate that diminished Th17 and Th1/17 responses, rather than Th1 responses, are particularly relevant to the abrogation of new relapsing disease activity observed in this cohort of patients with aggressive MS following chemoablation and HSCT.

Hematopoietic stem cell transplantation for systemic lupus erythematosus

Two streams of research are at the origin of the utilization of hematopoietic stem cell transplantation (HSCT) for severe autoimmune diseases (SADs). The allogeneic approach came from experimental studies on lupus mice, besides clinical results in coincidental diseases. The autologous procedure was encouraged by researches on experimental neurological and rheumatic disorders. At present the number of allogeneic HSCT performed for human SADs can be estimated to not over 100 patients, and the results are not greatly encouraging, considering the significant transplant-related mortality (TRM) and the occasional development of a new autoimmune disorder and/or relapses notwithstanding full donor chimerism. Autologous HSCT for refractory SLE has become a major target. Severe cases have been salvaged, TRM is low and diminishing, and prolonged clinical remissions are obtainable. Two types of immune resetting have been established, "re-education" and regulatory T cell (Tregs) normalization. Allogeneic HSCT for SLE seems best indicated for patients with disease complicated by an oncohematologic malignancy. Autologous HSCT is a powerful salvage therapy for otherwise intractable SLE. The duration of remission in uncertain, but a favorable response to previously inactive treatments is a generally constant feature. The comparison with new biological agents, or the combination of both, are to be ascertained.

[Stem cell-based treatment of neurologic diseases]

Therapeutic strategies based on stem cells are being increasingly used to treat a wide range of neurological diseases. Although these strategies were initially designed to replace dead cells in injured tissue, the potential of stem cells to migrate, secrete trophic factors, and immunomodulate allows their therapeutic use as a vehicle for gene therapy, as in Parkinson's disease, or as immunomodulators and neuroprotectors in diseases such as multiple sclerosis. This review will focus on current clinical and experimental evidence on the treatment of neurological disorders with strategies based on stem cells.

Autologous hematopoietic stem cell transplantation for autoimmune disease--is it now ready for prime time?

Current systemic therapies are rarely curative for patients with severe life-threatening forms of autoimmune disease (AID). During the past 15 years, autologous hematopoietic stem cell transplantation (HCT) has been demonstrated to cure some patients with severe AID refractory to all other available therapies, and thus AID has become an emerging indication for cell therapy. The sustained clinical effects after autologous HCT are better explained by qualitative change in the reconstituted immune repertoire rather than transient depletion of immune cells. Since 1996, more than 1300 AID patients have been registered by the European Group for Blood and Marrow Transplantation (EBMT) and almost 500 patients by the Center for International Blood and Marrow Transplant Research (CIBMTR). Autologous HCT is most commonly performed for patients with multiple sclerosis (MS) or systemic sclerosis (SSc). Systemic lupus, Crohn's disease, type I diabetes, and juvenile idiopathic arthritis are other common indications. Allogeneic transplants are still considered too toxic for use in AID, except for cases of immune cytopenia. Although biologic therapies have been effective at controlling the manifestations of the disease, they require continuous administration, thus raising questions about their increasing costs, morbidity, and mortality related to prolonged therapy. Perhaps it is a reasonable time to ask, "Is autologous HCT for severe AID now ready for prime time?" Yet, the paucity of controlled studies, the short-term toxicities, and the upcoming availability of second-generation biologic and targeted immunotherapies argues that perhaps HCT for AID should be still limited to clinical trials. In this article, we focus on the results of autologous HCT for MS and SSc because these are the two most commonly transplanted diseases. The promising data that is emerging may establish these diseases as standard indications for HCT.

Long-term efficacy of autologous haematopoietic stem cell transplantation in multiple sclerosis at a single institution in China

Autologous haematopoietic stem cell transplantation (AHSCT) is a promising treatment for multiple sclerosis (MS) patients who have not adequately responded to conventional therapies. We retrospectively evaluated the safety and long-term clinical outcome of AHSCT in MS patients in China. Twenty-five patients with various types of MS were treated with AHSCT. Peripheral blood stem cells were derived by leukapheresis after mobilized with granulocyte colony-stimulating factor. Then CD34+ cell selection of the graft was performed and anti-thymocyte globulin was given for T-cell depletion, with the conditioning regimen BEAM adopted and early and late toxicities recorded. Long-term responses were evaluated by the expanded disability status scale (EDSS), progression-free survival and gadolinium-enhanced magnetic resonance imaging scans. 10, 7 and 8 patients experienced neurological improvement, stabilization and progression, respectively. The median EDSS scores observed over 1-year follow-up after transplantation (5.5-7.0) were consistently lower than the baseline (8.0). The progression-free survival rate was 74, 65 and 48% at 3, 6 and 9 years post-transplant. 58% cases (7/12) had active lesions at baseline and all turned to inactive status in the years of follow-up. 25% cases (3/12) experienced progression after transplantation but had no active lesions in MRI over the whole follow-up period. 17% cases (2/12) without active lesions at baseline progressed active lesions in MRI. The major early toxicity resulted in fever and late toxicity caused transplantation-related mortality due to severe pneumonia and varicella-zoster virus hepatitis, respectively. AHSCT is a feasible treatment for severe MS and its long-term efficacy is favorable.

Autologous haematopoietic stem cell transplantation with an intermediate intensity conditioning regimen in multiple sclerosis: the Italian multi-centre experience

BACKGROUND

Over recent years numerous patients with severe forms of multiple sclerosis (MS) refractory to conventional therapies have been treated with intense immunosuppression followed by autologous haematopoietic stem cell transplantation (AHSCT). The clinical outcome and the toxicity of AHSCT can be diverse, depending on the various types of conditioning protocols and on the disease phase.

OBJECTIVES

To report the Italian experience on all the consecutive patients with MS treated with AHSCT with an intermediate intensity conditioning regimen, named BEAM/ATG, in the period from 1996 to 2008.

METHODS

Clinical and magnetic resonance imaging outcomes of 74 patients were collected after a median follow-up period of 48.3 (range = 0.8-126) months.

RESULTS

Two patients (2.7%) died from transplant-related causes. After 5 years, 66% of patients remained stable or improved. Among patients with a follow-up longer than 1 year, eight out of 25 subjects with a relapsing-remitting course (31%) had a 6-12 months confirmed Expanded Disability Status Scale improvement > 1 point after AHSCT as compared with one out of 36 (3%) patients with a secondary progressive disease course (p = 0.009). Among the 18 cases with a follow-up longer than 7 years, eight (44%) remained stable or had a sustained improvement while 10 (56%), after an initial period of stabilization or improvement with median duration of 3.5 years, showed a slow disability progression.

CONCLUSIONS

This study shows that AHSCT with a BEAM/ATG conditioning regimen has a sustained effect in suppressing disease progression in aggressive MS cases unresponsive to conventional therapies. It can also cause a sustained clinical improvement, especially if treated subjects are still in the relapsing-remitting phase of the disease.

Promising treatments of tomorrow for multiple sclerosis

The therapeutic options for multiple sclerosis are rapidly expanding. What was once seen as a disease with little hope for treatment is now a target of rapid drug development. Current therapies have demonstrated efficacy in limiting the impact of the disease, but none is fully effective in all patients. However, promising new treatments are on the horizon. In this review we will discuss potential novel immunomodulating drugs that are in advanced stages of investigation; these drugs include monoclonal antibodies, chimeric molecules, and oral therapies. The use of hematopoietic stem cells will also be discussed and, in addition, we will look farther ahead at possible novel targets for the development of new immunomodulatory or neuroprotective pharmaceuticals.

Fat-saturated post gadolinium T1 imaging of the brain in multiple sclerosis

BACKGROUND

Magnetic resonance imaging (MRI) is of vital importance in the diagnosis and follow-up of patients with multiple sclerosis (MS). Imaging sequences better demonstrating enhancing lesions can help in detecting active MS plaques.

PURPOSE

To evaluate the role of fat-saturated gadolinium-enhanced T1-weighted (T1W) images of the brain in MS and to assess the benefit of performing this additional sequence in the detection of enhancing lesions.

MATERIAL AND METHODS

In a prospective study over a six-month period, 70 consecutive patients with clinically diagnosed MS were enrolled. These constituted 14 male and 56 female patients between the ages of 21 and 44 years. All the patients underwent brain MRIs on a 1.5 Tesla Magnet. Gadolinium-enhanced T1 images with and without fat saturation were compared and results were recorded and analyzed using a conspicuity score and McNemar test.

RESULTS

There were a total of 157 lesions detected in 70 patients on post-contrast T1W fat-saturated images compared with 139 lesions seen on the post-contrast T1W fast spin-echo (FSE) images. This was because 18 of the lesions (11.5%) were only seen on the fat-saturated images. In addition, 15 lesions were more conspicuous on the fat saturation sequence (9.5%). The total conspicuity score obtained, including all the lesions, was 2.24 +/-0.60 (SD). Using the two-tailed McNemar test for quantitative analysis, the P value obtained was <0.0001.

CONCLUSION

T1W fat-saturated gadolinium-enhanced images show better lesion enhancement than T1W images without fat saturation.

Autologous hematopoietic stem cell transplantation in autoimmune diseases

The term 'autoimmune diseases' encompasses a spectrum of diseases whose clinical manifestations and, possibly, biological features vary widely. The results of conventional treatment are considered unsatisfactory in aggressive forms, with subsets of patients having short life expectancies. Relying on wide experimental evidence and more feeble clinical data, some research groups have used autologous hematopoietic stem cell transplantation (HSCT) in the most disabling autoimmune diseases with the aim of resetting the patient's immune system. Immunoablative conditioning regimens are preferred over their myeloablative counterparts, and some form of in vivo and/or ex vivo T-cell depletion is generally adopted. Despite 15 years' experience, published controlled clinical trials are still lacking, with the evidence so far available coming from pilot studies and registry surveys. In multiple sclerosis, clinical improvement, or at least lasting disease stabilization, can be achieved in the majority of the patients; nevertheless, the worst results are observed in patients with progressive disease, where no benefit can be expected from conventional therapy. Concerning rheumatologic diseases, wide experience has been acquired in systemic sclerosis, with long-term improvements in cutaneous disease being frequently reported, although visceral involvement remains unchanged at best. Autografting has proved to be barely effective in rheumatoid arthritis and quite toxic in juvenile idiopathic arthritis, whereas it leads to clinical remission and the reversal of visceral impairment in the majority of patients with systemic lupus erythematosus. A promising indication is Crohn's disease, in which long-term endoscopic remission is frequently observed. Growing experience with autologous HCST in autoimmune diseases has progressively reduced concerns about transplant-related mortality and secondary myelodysplasia/leukemia. Therefore, a sustained complete remission seems to be within the reach of autografting in some autoimmune diseases; in others, the indications, risks and benefits of autografting need to be better defined. Consequently, the search for new drugs should also be encouraged.

Lights and shadows of cyclophosphamide in the treatment of multiple sclerosis

Cyclophosphamide (cy) is an alkylating agent used to treat malignancies and immune-mediated inflammatory nonmalignant processes. It has been used as a treatment in cases of worsening multiple sclerosis (MS). Cy is currently used for patients whose disease is not controlled by beta-interferon or glatiramer acetate as well as those with rapidly worsening MS. The most commonly used regimens involve outpatient IV pulse therapy given with or without corticosteroids every 4 to 8 weeks. Side effects include nausea, headache, alopecia, pain, male and women infertility, bladder toxicity, and risk of malignancy. Previous studies suggest that cy is effective in patients in the earlier stages of disease, where inflammation predominates over degenerative processes. Given that early inflammatory events appear to correlate with later disability, a major question is whether strong anti-inflammatory drugs, such as cy, will have an impact on later degenerative changes if given early in the disease to halt inflammation.

A preliminary result of treatment of neuromyelitis optica with autologous peripheral hematopoietic stem cell transplantation

Autologous peripheral hematopoietic stem cell transplantation (APHSCT) was performed to treat a patient with neuromyelitis optica. We observed that the patient achieved clinical remission after APHSCT during 12 months of follow-up. The patient improved on the expanded disability status scale neurologic assessment and the Scripps neurologic rating scale worksheet scores on follow-up examination compared with baseline. The MRI abnormalities on T1WI and T2WI improved. The postpartum maternal blood helper T (CD3+CD4+ T cell) and the CD4+/CD8+ ratio were decreased, and the cytotoxic T (CD3+CD8+ T) cell increased. This shows that APHSCT in this patient with neuromyelitis optica appears to reduce the frequency of attacks with improvement in disability. However, a larger study with more patients and a longer follow-up would be required to assess the encouraging preliminary results.

Evidence for acute neurotoxicity after chemotherapy

OBJECTIVE

Chronic neurotoxicity is a recognized long-term complication following chemotherapy in a range of diseases. Neurotoxicity adversely affects patients' quality of life. The objective of this study is to examine whether there is evidence of acute neurotoxicity.

METHODS

This prospective study included patients with secondary progressive multiple sclerosis (SPMS-BMT, n = 14) and hematological malignancies (HM-BMT, n = 17) receiving chemotherapy as preconditioning for bone marrow transplant. The control groups included SPMS patients matched for demographic and clinical data (SPMS-PL, n = 14) and healthy controls (n = 14). Neurodegeneration was assessed at baseline and longitudinally (months 1, 2, 3, 6, 9, 12, 24, and 36), combining a clinical scale for disability (Expanded Disability Status Scale [EDSS]), a serum protein biomarker for neurodegeneration (neurofilaments, NfH-SMI35), and brain atrophy measures (magnetic resonance imaging).

RESULTS

Disability progression was significantly more acute and severe following chemotherapy compared to placebo. Immediately after starting chemotherapy, serum NfH-SMI35 levels increased in 79% (p < 0.0001) of SPMS-BMT patients and 41% (p < 0.01) of HM-BMT patients compared to 0% of SPMS-PL patients or healthy controls. In SPMS-BMT serum NfH-SMI35 levels were > 100-fold higher 1 month after chemotherapy (29.73ng/ml) compared to baseline (0.28ng/ml, p < 0.0001). High serum NfH-SMI35 levels persisting for at least 3 months were associated with sustained disability progression on the EDSS (p < 0.05). Brain atrophy rates increased acutely in SPMS-BMT (-2.09) compared to SPMS-PL (-1.18, p < 0.05).

INTERPRETATION

Neurotoxicity is an unwanted acute side effect of aggressive chemotherapy.

New approaches in the management of multiple sclerosis

Multiple sclerosis (MS) is a central nervous system chronic inflammatory disease that is characterized by an extensive and complex immune response. Scientific advances have occurred in immunology, pathophysiology, and diagnostic and clinical assessment tools, and recent discovery of unique therapeutic targets has spurred numerous Phase II and Phase III clinical trials. Reductions in MS relapse rates and improvements in T₂ or gadolinium-enhancing lesion burdens have been reported from Phase III trials that include fingolimod, alemtuzumab, cladribine, and rituximab. Promising Phase II trial data exist for teriflunomide, daclizumab, laquinimod, and fumarate. The optimism created by these favorable findings must be tempered with evaluation of the adverse effect profile produced by these new agents. Given the discovery of progressive multifocal leukoencephalopathy with the use of natalizumab, ongoing vigilance for rare and life-threatening reactions due to new agents should be paramount. Patients with MS often experience difficulty with ambulation, spasticity, and cognition. Recent clinical trial data from two Phase III dalfampridine-SR trials indicate certain patients receive benefits in ambulation. This article provides an overview of data from clinical trials of newer agents of potential benefit in MS.

Therapeutic approaches to multiple sclerosis: an update on failed, interrupted, or inconclusive trials of immunomodulatory treatment strategies

Multiple sclerosis (MS) continues to be a therapeutic challenge, and much effort is being made to develop new and more effective immune therapies. Particularly in the past decade, neuroimmunologic research has delivered new and highly effective therapeutic options, as seen in the growing number of immunotherapeutic agents and biologics in development. However, numerous promising clinical trials have failed to show efficacy or have had to be halted prematurely because of unexpected adverse events. Some others have shown results that are of unknown significance with regard to a reliable assessment of true efficacy versus safety. For example, studies of the highly innovative monoclonal antibodies that selectively target immunologic effector molecules have not only revealed the impressive efficacy of such treatments, they have also raised serious concerns about the safety profiles of these antibodies. These results add a new dimension to the estimation of risk-benefit ratios regarding acute or long-term adverse effects. Therapeutic approaches that have previously failed in MS have indicated that there are discrepancies between theoretical expectations and practical outcomes of different compounds. Learning from these defeats helps to optimize future study designs and to reduce the risks to patients. This review summarizes trials on MS treatments since 2001 that failed or were interrupted, attempts to analyze the underlying reasons for failure, and discusses the implications for our current view of MS pathogenesis, clinical practice, and design of future studies. In order to maintain clarity, this review focuses on anti-inflammatory therapies and does not include studies on already approved and effective disease-modifying therapies, albeit used in distinct administration routes or under different paradigms. Neuroprotective and alternative treatment strategies are presented elsewhere.

Autologous haematopoietic stem-cell transplantation in multiple sclerosis: benefits and risks

Autologous haematopoietic stem-cell transplantation has been evaluated over the last years as a possible new therapeutic strategy in severe forms of multiple sclerosis unresponsive to the approved therapies. Up to now, more than 400 patients have been treated and numerous are the phase I and phase II studies which addressed the feasibility of this treatment, the efficacy, side effects and transplant-related mortality. The clinical response is strongly related to the intensity of the conditioning regimen utilized as well as to the phase of the disease course in which the therapy is carried out. Rapidly evolving multiple sclerosis with a relapsing-remitting clinical course and MRI signs of activity are the cases that can take more advantage. The risk of mortality, which dropped in the last years to 2-3%, is still the main problem of this powerful therapy.

The therapeutic potential of mesenchymal stem cell transplantation as a treatment for multiple sclerosis: consensus report of the International MSCT Study Group

Current therapies for multiple sclerosis effectively reduce inflammation, but do little in terms of repair to the damaged central nervous system. Cell-based therapies may provide a new strategy for bolstering regeneration and repair through neuro-axonal protection or remyelination. Mesenchymal stem cells modulate pathological responses in experimental autoimmune encephalitis, alleviating disease, but also stimulate repair of the central nervous system through the release of soluble factors. Autologous and allogeneic mesenchymal stem cells have been safely administered to individuals with hemato-oncological diseases and in a limited number of patients with multiple sclerosis. It is therefore reasonable to move mesenchymal stem cells transplantation into properly controlled human studies to explore their potential as a treatment for multiple sclerosis. Since it is likely that the first such studies will probably involve only small numbers of patients in a few centers, we formed an international panel comprising multiple sclerosis neurology and stem cell experts, as well as immunologists. The aims were to derive a consensus on the utilization of mesenchymal stem cells for the treatment of multiple sclerosis, along with protocols for the culture of the cells and the treatment of patients. This article reviews the consensus derived from our group on the rationale for mesenchymal stem cell transplantation, the methodology for generating mesenchymal stem cells and the first treatment protocol for multiple sclerosis patients.

Hematopoietic stem cell transplantation in multiple sclerosis

Intensive immunosuppresion followed by hematopoietic stem cell transplantation (HSCT) has been suggested as potential treatment in severe forms of multiple sclerosis (MS). Since 1995 ca. 400 patients have been treated with HSCT. Stabilization or improvement occurred in almost 70% of cases at least for 3 years post-transplant. Magnetic resonance revealed the capacity of autologous HSCT to suppress or markedly reduce gadolinium-enhancing lesions. The progression of brain atrophy declined after two years post-HSCT. The profound immunological changes following autologous HSCT may result in restoration of self-tolerance. Relatively young patients with active inflammatory lesions of relatively short duration and rapidly progressive disease, but still low disability scores, unresponsive to conventional therapy seem the best candidates for transplantation. Transplant-related mortality was 6% in the first EBMT report and 5.3% in the second one. No deaths were reported since 2001. Very high-intensity conditioning regimen is associated with higher risk of toxicity without significant increase in efficacy. The effects of transplantation and transplantation-related morbidity are dependent on patient-selection, time of transplantation and conditioning regimens used.This review is a comprehensive study of the results obtained in several single-center and multicenter studies. Patient characteristics, transplantations steps, toxicity and clinical outcome have been monitored and compared.

Immuno-therapeutic potential of haematopoietic and mesenchymal stem cell transplantation in MS

In the last few years there has been extraordinary progress in the field of stem cell research. Two types of stem cells populate the bone marrow: haematopoietic stem/progenitor cells (HSC) and mesenchymal stem cells (MSC). The capacity of HSC to repopulate the blood has been known and exploited therapeutically for at least four decades. Today, haematopoietic stem cell transplantation (HSCT) holds a firm place in the therapy of some haematological malignancies, and a potential role of HSCT for treatment of severe autoimmune diseases has been explored in small-scale clinical studies. Multiple sclerosis (MS) is the noncancerous immune mediated disease for which the greatest number of transplants has been performed to date. The results of clinical studies are double-faced: on the one hand, HSCT has demonstrated powerful effects on acute inflammation, arresting the development of focal CNS lesions and clinical relapses; on the other hand, the treatment did not arrest chronic worsening of disability in most patients with secondary progressive MS, suggesting limited or no beneficial effects on the chronic processes causing progressive disability. MSC are a more recent addition to the range of experimental therapies being developed to treat MS. While interest in MSC usage was originally raised by their potential capacity to differentiate into different cell lineages, recent work showing their interesting immunological properties has led to a revised concept, envisioning their utilization for immuno-modulatory purposes. In this review we will summarize the current clinical and experimental evidence on HSC and MSC and outline some key questions warranting further investigation in this exciting research area.

Autologous haematopoietic stem-cell transplantation in multiple sclerosis

Intense immunosuppression followed by autologous haematopoietic stem-cell transplantation has been assessed over the past few years as a possible new therapeutic strategy in severe forms of multiple sclerosis. Pioneering studies began in 1995, and since then, more than 400 patients worldwide have been treated with this procedure. Small uncontrolled studies show that about 60-70% of treated cases do not progress in the follow-up period of at least 3 years. Transplant-related mortality, which was 5-6% in the first reported series, has reduced in the past 5 years to 1-2%. Relapses dramatically decrease and inflammatory MRI activity is almost completely suppressed. Autologous haematopoietic stem-cell transplantation is associated with qualitative immunological changes in the blood, suggesting that, beyond its immunosuppressive potential, it could also have some beneficial effect for the resetting of the immune system. Patients with severe, rapidly worsening multiple sclerosis who are unresponsive to approved therapies could be candidates for this treatment, but its clinical efficacy has still to be shown in large, prospective, controlled studies.