Autologous peripheral blood stem cell transplantation for severe multiple sclerosis

Exploring the therapeutic potential of autologous hematopoietic stem cell transplantation in progressive multiple sclerosis-a systematic review

BACKGROUND AND PURPOSE

The aim was to determine the value of autologous haematopoietic stem cell transplantation (aHSCT) as a therapeutic intervention for progressive multiple sclerosis (PMS) based on a systematic review of the current literature.

METHODS

All studies from the databases PubMed and Google Scholar published in English before February 2024 which provided individual data for PMS patients were systematically reviewed. PICO was defined as population (P), primary progressive MS and secondary progressive MS patients; intervention (I), treatment with aHSCT; comparison (C), none, disease-modifying therapy treated/relapsing-remitting MS cohorts if available; outcome (O), transplant-related mortality, progression-free survival (PFS) and no evidence of disease activity.

RESULTS

A total of 15 studies met the criteria including 665 patients with PMS (74 primary progressive MS, 591 secondary progressive MS) and 801 patients with relapsing-remitting MS as controls. PFS data were available for 647 patients. PMS patients showed more severe disability at baseline than relapsing-remitting MS patients. The average transplant-related mortality for PMS in 10 studies was 1.9%, with 10 deaths in 528 patients. PFS ranged from 0% to 78% in PMS groups 5 years after treatment initiation, demonstrating a high variability. No evidence of disease activity scores at 5 years ranged from 0% to 75%.

CONCLUSION

Based on the available data, aHSCT does not halt progression in people with PMS. However, there appears to be evidence of improved outcome in selected patients. Due to the heterogeneity of the available data, more comprehensive clinical trials assessing the efficacy of aHSCT across different patient groups are urgently needed to reduce variability and improve patient stratification.

Immunological outcomes of autologous hematopoietic stem cell transplantation for multiple sclerosis: a systematic review

Background

Autologous hematopoietic stem cell transplantation (AHSCT) is an extensive procedure that allows for the depletion of the immune system and its restoration from hemopoietic stem cells. The approach has been modified for the treatment of severe immune-mediated illnesses, including multiple sclerosis (MS), after being initially devised for the treatment of hematological malignancies.

Objective

This systematic review aims to determine and consolidate the information on the short-term and long-term immunological effects of AHSCT on the cellular level in MS patients.

Methods

The PubMed, Scopus, and Web of Science servers were used to conduct a systematic search in compliance with the PRISMA guidelines. The results were tabulated and analyzed.

Results

A total of 17 studies (10 clinical trials, 6 cohort studies, and 1 case-control study) were included in the final analysis, and 383 MS patients were analyzed. A significant decline in the cell count of CD4 T cells was reported when compared to the CD8 T cells, B cells, and NK cells. B cell count returned to baseline in 71.4% of the studies at the end of 6 months. The NK cell count was found to be above the baseline in 62.5% of studies.

Conclusion

AHSCT has been proven to be one of the most effective treatment modalities for MS in recent studies. However, debilitating complications due to immunological outcomes of the procedure have led to increased morbidity. Further research into this domain will help boost the success rate and efficacy of AHSCT.

Autologous Hematopoietic Stem-Cell Transplantation in Multiple Sclerosis: A Systematic Review and Meta-Analysis

INTRODUCTION

In 1995, the use of autologous hematopoietic stem-cell transplantation (AHSCT), which was previously used to treat hematological tumors, was introduced for severe autoimmune diseases such as multiple sclerosis (MS). AHSCT has proven its safety over the past few years due to technical advances and careful patient selection in transplant centers. While most studies have reported that AHSCT led to decreased Expanded Disability Status Scale (EDSS) scores, some patients reported increased EDSS scores following the procedure. Given the contradictory results, we aimed to conduct a comprehensive systematic review and meta-analysis to investigate the efficacy and safety of AHSCT.

METHODS

PubMed, Web of Science, and Scopus were searched in March 2022 using a predefined search strategy. We included cohort studies, clinical trials, case-control studies, and case series that investigated the efficacy or safety of AHSCT in patients with MS. PICO in the present study was defined as follows: problem or study population (P): patients with MS; intervention (I): AHSCT; comparison (C): none; outcome (O): efficacy and safety.

RESULTS

After a two-step review process, 50 studies with a total of 4831 patients with MS were included in our study. Our analysis showed a significant decrease in EDSS score after treatment (standardized mean difference [SMD]: -0.48, 95% CI -0.75, -0.22). Moreover, the annualized relapse rate was also significantly reduced after AHSCT compared to the pretreatment period (SMD: -1.58, 95% CI -2.34, -0.78). The pooled estimate of progression-free survival after treatment was 73% (95% CI 69%, 77). Furthermore, 81% of patients with MS who received AHSCT remained relapse-free (95% CI 76%, 86%). Investigating event-free survival, which reflects the absence of any disease-related event, showed a pooled estimate of 63% (95% CI 54%, 73%). Also, the MRI activity-free survival was 89% (95% CI 84%) among included studies with low heterogeneity. New MRI lesions seem to appear in nearly 8% of patients who underwent AHSCT (95% CI 4%, 12%). Our meta-analysis showed that 68% of patients with MS experience no evidence of disease activity (NEDA) after AHSCT (95% CI 59%, 77). The overall survival after transplantation was 94% (95% CI 91%, 96%). In addition, 4% of patients died from transplant-related causes (95% CI 2%, 6%).

CONCLUSION

Current data encourages a broader application of AHSCT for treating patients with MS while still considering proper patient selection and transplant methods. In addition, with increasing knowledge and expertise in the field of stem-cell therapy, AHSCT has become a safer treatment approach for MS.

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.

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.

A review of hematopoietic stem cell transplantation for autoimmune diseases: multiple sclerosis, systemic sclerosis and Crohn's disease. Position paper of the Brazilian Society of Bone Marrow Transplantation

Autoimmune diseases are an important field for the development of bone marrow transplantation, or hematopoietic stem cell transplantation. In Europe alone, almost 3000 procedures have been registered so far. The Brazilian Society for Bone Marrow Transplantation (Sociedade Brasileira de Transplantes de Medula Óssea) organized consensus meetings for the Autoimmune Diseases Group, to review the available literature on hematopoietic stem cell transplantation for autoimmune diseases, aiming to gather data that support the procedure for these patients. Three autoimmune diseases for which there are evidence-based indications for hematopoietic stem cell transplantation are multiple sclerosis, systemic sclerosis and Crohn's disease. The professional stem cell transplant societies in America, Europe and Brazil (Sociedade Brasileira de Transplantes de Medula Óssea) currently consider hematopoietic stem cell transplantation as a therapeutic modality for these three autoimmune diseases. This article reviews the evidence available.

Clinical neurorestorative cell therapies: Developmental process, current state and future prospective

Clinical cell therapies (CTs) for neurological diseases and cellular damage have been explored for more than 2 decades. According to the United States Food and Drug Administration, there are 2 types of cell categories for therapy, namely stem cell-derived CT products and mature/functionally differentiated cell-derived CT products. However, regardless of the type of CT used, the majority of reports of clinical CTs from either small sample sizes based on single-center phase 1 or 2 unblinded trials or retrospective clinical studies showed effects on neurological improvement and the ability to either partially or temporarily thwart the deteriorating cellular processes of the neurodegenerative diseases. There have been only a few prospective, multicenter, randomized, double- blind placebo-control clinical trials of CTs so far in this developing novel area that have shown negative results, and more clinical trials are needed. This will expand our knowledge in exploring the type of cells that yield promising results and restore damaged neurological structure and functions of the central nervous system based on higher level evidence-based medical data. In this review, we briefly introduce the developmental process, current state, and future prospective for clinical neurorestorative CT.

Clinical Cell Therapy Guidelines for Neurorestoration (IANR/CANR 2017)

Cell therapy has been shown to be a key clinical therapeutic option for central nervous system diseases or damage. Standardization of clinical cell therapy procedures is an important task for professional associations devoted to cell therapy. The Chinese Branch of the International Association of Neurorestoratology (IANR) completed the first set of guidelines governing the clinical application of neurorestoration in 2011. The IANR and the Chinese Association of Neurorestoratology (CANR) collaborated to propose the current version "Clinical Cell Therapy Guidelines for Neurorestoration (IANR/CANR 2017)". The IANR council board members and CANR committee members approved this proposal on September 1, 2016, and recommend it to clinical practitioners of cellular therapy. These guidelines include items of cell type nomenclature, cell quality control, minimal suggested cell doses, patient-informed consent, indications for undergoing cell therapy, contraindications for undergoing cell therapy, documentation of procedure and therapy, safety evaluation, efficacy evaluation, policy of repeated treatments, do not charge patients for unproven therapies, basic principles of cell therapy, and publishing responsibility.

Stem cell transplantation therapy for multifaceted therapeutic benefits after stroke

One of the exciting advances in modern medicine and life science is cell-based neurovascular regeneration of damaged brain tissues and repair of neuronal structures. The progress in stem cell biology and creation of adult induced pluripotent stem (iPS) cells has significantly improved basic and pre-clinical research in disease mechanisms and generated enthusiasm for potential applications in the treatment of central nervous system (CNS) diseases including stroke. Endogenous neural stem cells and cultured stem cells are capable of self-renewal and give rise to virtually all types of cells essential for the makeup of neuronal structures. Meanwhile, stem cells and neural progenitor cells are well-known for their potential for trophic support after transplantation into the ischemic brain. Thus, stem cell-based therapies provide an attractive future for protecting and repairing damaged brain tissues after injury and in various disease states. Moreover, basic research on naïve and differentiated stem cells including iPS cells has markedly improved our understanding of cellular and molecular mechanisms of neurological disorders, and provides a platform for the discovery of novel drug targets. The latest advances indicate that combinatorial approaches using cell based therapy with additional treatments such as protective reagents, preconditioning strategies and rehabilitation therapy can significantly improve therapeutic benefits. In this review, we will discuss the characteristics of cell therapy in different ischemic models and the application of stem cells and progenitor cells as regenerative medicine for the treatment of stroke.

The role of autologous haemopoietic stem cell transplantation in the treatment of autoimmune disorders

Autologous haemopoietic stem cell transplantation (HSCT) has been used for over 30 years for malignant haematological diseases, such as myeloma and lymphoma, with considerable success. More recently this procedure has been adopted as a form of high dose immunosuppression in selected patients with autoimmune diseases that are resistant to conventional therapies. Animal models have previously outlined the rationale and validity of HSCT in patients with these non-malignant, but in many cases, life-threatening conditions. Recent data have that deletion of putative autoreactive immune clones with reconstitution of a thymic driven, tolerant immune system occurs in HSCT for auto-immune patients. Two randomised control trials have confirmed that HSCT is superior to monthly cyclophosphamide in systemic sclerosis with a highly significant disease free and overall survival benefit demonstrated in the Autologous Stem cell Transplantation International Scleroderma trial. Over 2000 patients worldwide with autoimmune conditions have been treated with HSCT - the commonest indications being multiple sclerosis (MS) and systemic sclerosis. Encouraging relapse free survival of 70-80% at 4 years, in heavily pre-treated MS patients, has been demonstrated in Phase II trials. A Phase III trial in MS patients who have failed interferon is currently accruing patients. Future challenges include improvements in safety of HSCT, particularly in cardiac assessment of systemic sclerosis patients, cost-benefit analyses of HSCT compared to standard therapy and establishment of centres of excellence to continue to enhance the safety and benefit of this exciting new therapy.

Standard recommendations for the application of Chinese clinical cell therapy for neurorestoration (2012)

Cell therapy has been shown to be a promising alternative therapy for neurorestoration, and more than 30 different types of cells have been shown to possess some capability to restore lost or damaged neurological functions. Chinese physicians have successfully applied cell therapy to many neurological diseases and damages in the clinic and contributed to establish a discipline of neurorestoratology. To standardize the clinical procedures of cell therapy as one of the strategies for treating neurological disorders, the Chinese Branch of the International Association of Neurorestoratology (IANR) and the Preparatory Committee of Chinese Association of Neurorestoratology recently completed the Standard Recommendations (2012) for the Application of Chinese Clinical Cell Therapy for Neurorestoration. We hope these recommendations will guide clinical practice in applying cell therapy for neurorestoration, which will therein offer a reference for both Chinese and other countries' governments to make relevant official regulations. This manuscript is published as part of the International Association of Neurorestoratology (IANR) supplement issue of Cell Transplantation.

Hematopoietic stem cell therapy for multiple sclerosis: top 10 lessons learned

Reports from more than 600 hematopoietic stem cell transplants (HSCT) have appeared in the medical literature for the last 1 and one-half decades. The patient's own stem cells are harvested and stored temporarily while high doses of chemotherapy and biologics are used to destroy the auto-destructive immune system. The immune system is regenerated from the infused autologous hematopoietic stem cells. Increasing clinical experience has refined patient selection criteria and management in the peri-transplant period leading to a reduction in treatment-related complications. HSCT, when used to treat patients with aggressive highly active multiple sclerosis, can reduce or eliminate ongoing clinical relapses, halt further progression, and reduce the burden of disability in some patients, in the absence of chronic treatment with disease-modifying agents. The top 10 lessons learned from the growing experience using HSCT for the treatment of multiple sclerosis are discussed.

Stem cell therapy for multiple sclerosis: preclinical evidence beyond all doubt?

Stem cell transplantation holds great promise for restoration of neural function in various neurodegenerative disorders, including multiple sclerosis (MS). However, many questions remain regarding the true efficacy and precise mode of action of stem cell-based therapeutic approaches. Therefore, in this article, we will first discuss the ideal route and/or timing of stem cell-based therapies for experimental autoimmune encephalomyelitis (EAE), the most used preclinical animal model for MS. Next, we will provide an overview of the proposed mechanisms that contribute to the beneficial effects of stem cell transplantation observed during the treatment of rodent EAE. Reviews of current and past literature clearly demonstrate conceptual changes in the development of stem cell-based approaches for EAE/MS, leading to the identification of several major challenges to be tackled before (stem) cell therapy for rodent EAE can be safely and successfully translated to human therapy for MS.

A prospective, randomized, controlled trial of autologous haematopoietic stem cell transplantation for aggressive multiple sclerosis: a position paper

Background:

Haematopoietic stem cell transplantation (HSCT) has been tried in the last 15 years as a therapeutic option in patients with poor-prognosis autoimmune disease who do not respond to conventional treatments. Worldwide, more than 600 patients with multiple sclerosis (MS) have been treated with HSCT, most of them having been recruited in small, single-centre, phase 1–2 uncontrolled trials. Clinical and magnetic resonance imaging outcomes from case series reports or Registry-based analyses suggest that a major response is achieved in most patients; quality and duration of response are better in patients transplanted during the relapsing–remitting phase than in those in the secondary progressive stage.

Objectives:

An interdisciplinary group of neurologists and haematologists has been formed, following two international meetings supported by the European and American Blood and Marrow Transplantation Societies, for the purpose of discussing a controlled clinical trial, to be designed within the new scenarios of evolving MS treatments.

Conclusions:

Objectives of the trial, patient selection, transplant technology and outcome assessment were extensively discussed. The outcome of this process is summarized in the present paper, with the goal of establishing the background and advancing the development of a prospective, randomized, controlled multicentre trial to assess the clinical efficacy of HSCT for the treatment of highly active MS.

Autologous hematopoietic cell transplantation following high-dose immunosuppressive therapy for advanced multiple sclerosis: long-term results

The purpose of the study was to determine the long-term safety and effectiveness of high-dose immunosuppressive therapy (HDIT) followed by autologous hematopoietic cell transplantation (AHCT) in advanced multiple sclerosis (MS). Total body irradiation, cyclophosphamide, and antithymocyte globulin were followed by transplantation of autologous, CD34-selected peripheral blood stem cells (PBSC). Neurological examinations, brain MRIs and cerebrospinal fluid (CSF) for oligoclonal bands (OCB) were serially evaluated. Patients (n=26, mean EDSS=7.0, 17 secondary progressive, 8 primary progressive, 1 relapsing/remitting) were followed for a median of 48 months after HDIT followed by AHCT. The 72-month probability of worsening ≥ 1.0 EDSS point was 0.52 (95% CI, 0.30 to 0.75). Five patients had an EDSS at baseline of ≤ 6.0; four of these had not failed treatment at last study visit. OCB in CSF persisted with minor changes in the banding pattern. Four new or enhancing lesions were seen on MRI, all within 13 months of treatment. In this population with high baseline EDSS, a significant proportion of patients with advanced MS remained stable as long as 7 years after transplant. Non-inflammatory events may have contributed to neurological worsening after treatment. HDIT/AHCT may be more effective in patients with less advanced relapsing/remitting MS.

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.

Hematopoietic SCT for the treatment of multiple sclerosis

Multiple sclerosis (MS) is the leading autoimmune indication for autologous hematopoietic SCT (aHSCT). Patient selection criteria and transplant interventions have been refined through a series of cohort and registry studies. High- and low-intensity chemotherapy-based conditioning regimens have been used, creating trade-offs between toxicity and effectiveness. TBI has been associated with greater toxicity and poor outcomes. aHSCT stops MS relapses and lessens the disability in malignant MS, which otherwise rapidly incapacitates patients. Better responses occur in progressive MS earlier in the disease when it has a more inflammatory nature. aHSCT prevents further disability in many patients, but some actually recover from their infirmities. Current regimens and supportive care result in very low morbidity and mortality. MS patients experience unique complications in addition to the expected toxicities. Cytokines used alone for stem-cell mobilization may induce MS flares but are safe to be used in combination with steroids or cytotoxic agents. Urinary tract infections, herpes virus reactivation and an engraftment syndrome may occur early after aHSCT. Rarely secondary autoimmune diseases have been reported late after HSCT. Increasing experience in caring for patients with MS has reduced the frequency and severity of toxicity. Conceived as an opportunity to 'reboot' a tolerant immune system, aHSCT is successful in treating patients with MS that is refractory to conventional immunomodulatory drugs.

High-dose immunoablation with autologous haematopoietic stem cell transplantation in aggressive multiple sclerosis: a single centre 10-year experience

There are multiple sclerosis patients who suffer from an aggressive course of the disease with severe relapses and rapid accumulation of disability despite adequate treatment. In such cases high-dose immunoablation with autologous haematopoietic stem cell transplantation (ASCT) may be considered. Our objective was to report our experience with 26 multiple sclerosis patients treated with ASCT within the years 1998-2008. Twenty-six patients (Expanded Disability Status Scale 2.5-7.5 (median 6.0), multiple sclerosis duration 2-19 years (median 7)) with aggressive multiple sclerosis underwent autologous haematopoietic stem cell transplantation. Stem cells were mobilized by high-dose cyclophosphamide and granulocyte colony-stimulating factor, BEAM (carmustine, etoposide, cytarabine, melphalan) was used for immunoablation. Patients were evaluated at baseline and every six months post ASCT for adverse events and clinical outcome. Follow-up period was 11-132 months (median 66). Progression-free survival was calculated using the Kaplan- Meier method. At 3 and 6 years of follow-up 70.8% and 29.2% of patients respectively were free of progression. Patients with relapsing multiple sclerosis course, disease duration <5 years and age <35 years had a more favourable outcome. There was no death within 100 days after ASCT. We conclude that ASCT represents a viable and effective treatment option for aggressive multiple sclerosis.

Autologous stem cell transplantation in autoimmune and rheumatic diseases: from the molecular background to clinical applications

Autoimmune diseases have a multifactorial origin. Because of disturbances of the immune system, autoreactive T and B cells target self-antigens, leading to permanent organ damage. Despite novel therapeutic protocols, the disease course is chronic and in many instances the outcome is lethal. The efficacy of stem cell therapy has been observed in autoimmune animal models and in autoimmune diseases related to haematological abnormalities. Although the therapy is more than 30 years old, its broad spread has been delayed by the serious side-effects due to the conditioning treatments based on oncological protocols. Evaluation of the data of patients who have undergone autologous stem cell therapy reinforced the view that protocols used for conditioning treatments, mostly causing lymphoablation, and procedures carried out in specialist centres significantly reduced mortality, with an almost optimal therapeutical efficacy. New, multicentre investigations have been launched to compare the efficacy of various protocols. In this review, we summarize certain aspects of the molecular background of autologous stem cell transplantation and also depict the response to therapy in various autoimmune and rheumatic diseases.

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.

Autologous peripheral blood stem cell transplantation for chronic acquired demyelinating neuropathy

Six patients with chronic acquired demyelinating neuropathy (CADP) were treated with autologous peripheral blood stem cell transplantation (PBSCT). Two with polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes (POEMS) syndrome improved-improvement was sustained in one but relapsed and required repeat transplant in the other. Two of the three with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and one with an IgM paraprotein and antibodies to nerve improved--of the responders, one relapsed after 18 months and the other was in remission after 6 months. Four developed neutropenic septicemia and pneumonia. The role of PBSCT in CADP refractory to other treatment deserves further investigation but the serious adverse events and lack of sustained response in some patients emphasize the need for caution.

Early highly aggressive MS successfully treated by hematopoietic stem cell transplantation

Background

During the last 15 years, high-dose chemotherapy with autologous hematopoietic stem cell transplantation (HSCT) has globally been performed for severe multiple sclerosis (MS). Most patients have been in progressive phase with long disease duration. As a rule, treatment effect has been minor or moderate.

Patients

Since 2004, we have performed HSCT in nine young patients with “malignant” relapsing–remitting MS. Criteria for treatment were short duration of disease; very frequent, severe relapses; recent improvement periods indicating potential for recovery after strong immunosuppression.

Findings

Median age at treatment was 27 (range 9–34) years, MS duration 26 (4–100) months, and annualized relapse rate 10 (4–12). Median Disability Status Scale (extended disability status scale, EDSS) at HSCT was 7.0 (3.5–8.0). Median follow-up time April 2008 is 29 (23–47) months. Median EDSS improvement is 3.5 (1.0–7.0), clearly surpassing most previous reports. One patient relapsed mildly with rapid recovery 7 months after HSCT. All patients are otherwise stable, median EDSS being 2.0 (0–6.0). Before HSCT, 61 relapses occurred in 82 patient months; during follow-up, one relapse in 289 patient months.

Conclusion

This small series of patients with “malignant” relapsing–remitting MS suggests HSCT to be an effective treatment option for this relatively rare disease course. It further suggests that future criteria for HSCT in MS should be close to the present ones.

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.

Autologous and allogeneic hematopoietic stem cell transplantation for Multiple Sclerosis: perspective on mechanisms of action

Multiple Sclerosis (MS) is a frequent demyelinating immune-mediated disease of the central nervous system (CNS) that affects principally young adults and leads to severe physical and cognitive impairment. The current standard treatment makes use of the immune modulators beta-interferon, glatiramer acetate and natalizumab, or immunosuppressants such as mitoxantrone. However, these agents are only partially effective and in a number of patients fail to achieve satisfactory disease control. Autologous hematopoietic stem cell transplantation (HSCT) is being explored in the treatment of severe MS as a means of delivering high-dose immunosuppression followed by 'rescue' of the immuno-hematopoietic system with autologous HSC. The potential therapeutic benefit is based on the concept of so-called 'resetting' the immune system. The use of allogeneic HSCT as a possible therapeutic approach for severe MS is inspired by case reports of MS patients that underwent allogeneic HSCT for a concomitant hematological malignancy, and subsequently is supported by data from rodent models of MS. Allogeneic HSCT may offer specific therapeutic effects, such as the replacement of the autoreactive immune compartment by healthy allogeneic cells and the development of a graft-versus-autoimmunity (GVA) effect. Here, we review the currently available experimental and clinical evidence to support the role of autologous and allogeneic HSCT in MS.

Stem cell transplantation in Multiple Sclerosis: Safety and Ethics

Stem cell therapy is considered a promising strategy aiming at neuronal and glial cell replacement or neuroprotection in neurological diseases affecting the brain and spinal cord. Multiple Sclerosis (MS), characterized by inflammation-induced destruction of the myelin sheath surrounding axons leading to conduction deficits and variability of clinical signs, is not an exception. MS is considered an autoimmune disease and, in the last few years, an intense immunodepletion followed by autologous hematopoietic-stem-cell transplant (HSCT) is being assessed as potential therapeutical strategy for severe patients unresponsive to the immunomodulatory and immunosuppressive treatment. Partially supported by evidence in animal models and by anecdotal reports on the beneficial effects on MS patients with concomitant malignant diseases, HSCT programs for MS have been initiated worldwide and follow-up data are accumulating. A Consensus Meeting has been held in Milano (1998) providing a document that defined criteria for patient selection, transplantation procedures, and outcome evaluations. Nowadays the high number of patients already treated allows us to draw initial conclusions related to clinical efficacy. After careful monitoring of the available data and improvement of the procedure, safety seems not to be anymore an issue. Ethics of HSCT deserve, on the contrary, a profound evaluation: the procedure is a multistep process with manifold options, each step with different ethical implications. Even more difficult appears the definition of the MS patient selection criteria for HSCT. The informed consensus needs to be exhaustive for the full comprehension of a complex procedure. In conclusion, although HCST is today an established therapeutical option for MS patients, safety and ethical issues need to be further clarified.

Enhancing effect of IL-1alpha on neurogenesis from adult human mesenchymal stem cells: implication for inflammatory mediators in regenerative medicine

Mesenchymal stem cells (MSCs) are mesoderm-derived cells, primarily resident in adult bone marrow. MSCs show lineage specificity in generating specialized cells such as stroma, fat, and cartilage. MSCs express MHC class II and function as phagocytes and APCs. Despite these immune-enhancing properties, MSCs also exert veto functions and show evidence for allogeneic transplantation. These properties, combined with ease in isolation and expansion, demonstrate MSCs as attractive candidates for tissue repair across allogeneic barriers. MSCs have also been shown to transdifferentiate in neuronal cells. We have reported expression of the neurotransmitter gene, Tac1, in MSC-derived neuronal cells, with no evidence of translation unless cells were stimulated with IL-1alpha. This result led us to question the potential role of immune mediators in the field of stem cell therapy. Using Tac1 as an experimental model, IL-1alpha was used as a prototypical inflammatory mediator to study functions on MSC-derived neuronal cells. Undifferentiated MSCs and those induced to form neurons were studied for their response to IL-1alpha and other proinflammatory cytokines using production of the major Tac1 peptide, substance P (SP), as readout. Although IL-1alpha induced high production of SP, a similar effect was not observed for all tested cytokines. The induced SP was capable of reuptake via its high-affinity NK1R and was found to stabilize IL-1R mRNA. IL-1alpha also enhanced the rate of neurogenesis, based on expression of neuronal markers and cRNA microarray analyses. The results provide evidence that inflammatory mediators need to be considered when deciding the course of MSC transplantation.