Guidelines for autologous blood and marrow stem cell transplantation in multiple sclerosis: a consensus report written on behalf of the European Group for Blood and Marrow Transplantation and the European Charcot Foundation. BMT-MS Study Group

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.

Autologous bone marrow transplantation for the treatment of multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system and represents one of the leading causes of neurologic disability in young adults. Current treatments for MS have shown limited efficacy in patients with either a progressive or an aggressive disease course. Hematopoietic stem cell transplantation (HSCT) has been proposed to control or even cure refractory cases of MS. Indeed, HSCT is able to temporarily eradicate the autoreactive cells and to reset the aberrant immune response to self-antigens. In the last decade, owing to the growing experience in selecting the most appropriate patients to transplant and the recent advances in chemotherapeutic and support regimens, the transplant-related mortality of autologous HSCT in MS patients dropped down to 1,3 % and the progression-free survival ranges from 47 % to 100 %. Altogether, these data support autologous HSCT as a possible second-line therapy for refractory MS.

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.

Induction of antigen-specific tolerance through hematopoietic stem cell-mediated gene therapy: the future for therapy of autoimmune disease?

Based on the principle that immune ablation followed by HSC-mediated recovery purges disease-causing leukocytes to interrupt autoimmune disease progression, hematopoietic stem cell transplantation (HSCT) has been increasingly used as a treatment for severe autoimmune diseases. Despite clinically-relevant outcomes, HSCT is associated with serious iatrogenic risks and is suitable only for the most serious and intractable diseases. A further limitation of autologous HSCT is that relapse rates can be high, suggesting disease-causing leukocytes are incompletely purged or the environmental and genetic determinants that drive disease remain active. Incorporation of antigen-specific tolerance approaches that synergise with autologous HSCT could reduce or prevent relapse. Further, by reducing the requirement for highly toxic immune-ablation and instead relying on antigen-specific tolerance, the clinical utility of HSCT could be significantly diversified. Substantial progress has been made exploring HSCT-mediated induction of antigen-specific tolerance in animal models but studies have focussed on primarily on prevention of autoimmune diseases. However, as diagnosis of autoimmune disease is often not made until autoimmune disease is well developed and populations of autoantigen-specific pathogenic effector and memory T cells have become well established, immunotherapies must be developed to address effector and memory T-cell responses which have traditionally been considered the key impediment to immunotherapy. Here, focusing on T-cell mediated autoimmune diseases we review progress made in antigen-specific immunotherapy using HSCT-mediated approaches, induction of tolerance in effector and memory T cells and the challenges for progression and clinical application of antigen-specific 'tolerogenic' HSCT therapy.

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.

Clinical outcome of autologous peripheral blood stem cell transplantation in opticospinal and conventional forms of secondary progressive multiple sclerosis in a Chinese population

To evaluate clinical outcomes of autologous peripheral blood stem cell transplantation (APBCST) between opticospinal multiple sclerosis (OSMS) and conventional multiple sclerosis (CMS) during disease progressive stage in a Chinese population. Thirty-six secondary progressive MS patients, among whom 21 were with OSMS and 15 with CMS, underwent APBSCT and were followed up for an average of 48.92 months (range, 10-91 months). Peripheral blood stem cells were obtained by leukapheresis after mobilization with granulocyte colony-stimulating factor. Modified BEAM conditioning regimen (Tiniposide, melphalan, carmustin, and cytosine arabinoside) were administered. Outcomes were evaluated using the expanded disability status scale (EDSS). No maintenance treatment was administered if there was no disease progression. No treatment-related mortality occurred. Among the 36 patients, one OSMS patient dropped during the follow-up. Among the 22 relapse-free patients, 20 were with continuous neurological improvement without any relapse events, and two remained in neurologically stable states. Among the 13 relapse patients, seven had experienced of neurological relapse, but with no progression during the follow-up period; and six experienced neurological deterioration after transplantation and needed further immunosuppressant treatment. The confirmed relapse-free survival rate was 62.9% and progression-free survival rate was 83.3% after 91 months according to Kaplan and Meier survival curves. Eleven of the 20 OSMS patients (55%) and two of the 15 CMS patients (13.3%) stayed in disease active group (P = 0.014). For the 20 OSMS patients, the overall EDSS score decreased significantly after transplantation (P = 0.016), while visual functions had no significant improvement (P = 0.716). Progressive OSMS has a higher relapse rate than CMS following APBSCT.

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.

The contribution of hematopoietic stem cells to beta-cell replacement

Hemopoietic stem cells (HSCs) are commonly used for curing malignant and nonmalignant hematopoiesis disorders. In recent years, HSC potential giving rise to multilineage progeny has been reported. This issue, together with their availability and number, has made them ideal candidates for beta-cell replacement in diabetic patients. HSC capacity to differentiate to insulin-producing cells has been at the center of debate for the past 5 years and it now seems that their role could more likely be that of helper cells able to facilitate survival or stimulate proliferation of endogenous beta cells. In addition, clinical studies are ongoing about the possible use of HSCs to stop autoimmune destruction at the onset of diabetes or to induce tolerance through microchimerism in pancreatic islet transplantation.

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.

[Use of mitoxantrone in early multiple sclerosis with malignant disease course. Observational study in 30 patients with clinical and MRI outcomes after one year]

INTRODUCTION

In an observational multicenter study, we analyzed retrospectively 30 patients with malignant form of multiple sclerosis (MS) treated with mitoxantrone the year following the first neurological event.

METHODS

The 30 patients were selected according to Weinshenker criteria of malignant MS (either a "catastrophic" relapse or a quickly aggressive form). We compared clinical and MRI findings the year before with the year following mitoxantrone onset treatment: annualized relapse rates (ARR), EDSS score and percentage of patients with gadolinium enhancing lesions on MRI.

RESULTS

A total of 87 relapses were observed in the 5.7 months before and 10 during the year following onset of mitoxantrone treatment. The ARR decreased by 95% (6.0+/-2 before and 0.3+/-0.7 after). Twenty-four patients (80%) were relapse-free one year after onset of mitoxantrone treatment. The EDSS score improved in 87% of MS patients and the mean EDSS decreased by 1.9. Ninety-seven percent had at least gadolinium enhancing lesions before the start of mitoxantrone treatment as compared to 17% after.

CONCLUSION

In our experience, mitoxantrone had a rapid and strong impact on the malignant forms of MS with a short disease duration. In this MS subgroup, mitoxantrone should be considered as an early treatment option.

Autologous umbilical cord blood infusion for type 1 diabetes

OBJECTIVE

The physical, emotional, and economic costs of type 1 diabetes (T1D) mandate continued efforts to develop effective strategies to prevent or reverse the disease. Herein, we describe the scientific and therapeutic rationale underlying efforts utilizing umbilical cord blood (UCB) as a therapy for ameliorating the progression of this autoimmune disease.

MATERIALS AND METHODS

We recently embarked on a pilot study to document the safety and potential efficacy of autologous UCB infusion in subjects with T1D. Under this protocol, patients recently diagnosed with the disease and for whom autologous cord blood is stored, undergo infusion. Studies are performed before infusion and every 3 to 6 months postinfusion for immunologic and metabolic assessment. To date, 15 autologous infusions have been performed.

RESULTS

Preliminary observations suggest that autologous cord blood transfusion is safe and provides some slowing of the loss of endogenous insulin production in children with T1D. Mechanistic studies demonstrate that umbilical cord blood contains highly functional populations of regulatory T cells (Treg) and that increased Treg populations may be found in the peripheral blood of subjects more than 6 months after cord blood infusion. We provide the rationale for cord blood-based therapies, a summary of our initial protocol, and plans for future studies designed to explore the potential of cord blood-derived regulatory T cells to treat T1D.

CONCLUSIONS

Prolonged follow-up and additional mechanistic efforts are urgently needed to determine if umbilical cord blood-derived stem cells can be used as part of safe and effective therapies for T1D.

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.

Emerging therapies for multiple sclerosis

This review examines the mode of action, safety profile and clinical efficacy of some of the most promising new therapeutic strategies for multiple sclerosis. Autologous hematopoietic stem cell transplantation can regenerate a new and tolerant immune system and is a potentially effective rescue therapy in a subset of patients with aggressive forms of MS refractory to approved immunomodulatory and immunosuppressive agents. High-dose cyclophosphamide without stem cell support is suggested to induce prolonged remissions through similar immunological mechanisms with less toxicity. Fingolimod (FTY720) is a novel oral immunomodulating agent that acts through preventing lymphocyte recirculation from lymphoid organs. Monoclonal antibody therapy has provided scientists and clinicians the opportunity to rationally direct the therapeutic intervention against specific molecules. Targeting molecules of the immune system such as CD52 (alemtuzumab), CD25 (daclizumab), VLA-4 (natalizumab) and CD20 (rituximab) have resulted in potent immunomodulatory effects through sometimes unpredicted mechanisms. The potential of immunoglobulins to induce remyelination in the CNS is being investigated in an attempt to develop therapies promoting tissue repair and functional recovery. The evidence supporting the potential of these emerging immunotherapies suggests that strong progress is being made in the development of effective cures for multiple sclerosis.

Resetting the adaptive immune system after autologous stem cell transplantation: lessons from responses to vaccines

Autologous stem cell transplantation (ASCT) to treat autoimmune diseases (AID) is thought to reset immunological memory directed against autoantigens. This hypothesis can only be studied indirectly because the exact nature of the pathogenetic autoantigens is unknown in most AID. Therefore, 19 children with juvenile idiopathic arthritis (JIA) or systemic lupus erythematodes (SLE) and 10 adults with multiple sclerosis (MS) were vaccinated with the T-cell-dependent neoantigen rabies and the recall antigen tetanus toxoid after, respectively before, bone marrow harvest. Both vaccinations were repeated after ASCT. All except two of the responders mounted a primary antibody response to rabies after revaccination, and 44% of the responders mounted a primary antibody response to tetanus boost after ASCT. These data show that immunological memory to a neoantigen is lost in most patients with AID after immunoablative pretreatment; however, memory to a recall antigen boosted before bone marrow harvest is only lost in part of the patients. Disease progression was arrested in all patients with JIA/SLE except one, but only in a minority of MS patients. Clinical outcome on a per case basis was not associated with the profile of the immune response toward the vaccination antigens after ASCT.

Autologous Haematopoietic Stem Cell Transplantation for the Treatment of Multiple Sclerosis

Introduction: Autologous haematopoietic stem cell transplantation (auto-HSCT) has been performed for severe multiple sclerosis (MS) refractory to standard therapy with increasing frequency worldwide. However, experience in Asia employing this modality in MS has been limited. In this review, we explored the pathophysiology of autoimmunity and the underlying rationale for auto-HSCT in treating autoimmune diseases including MS, as well as existing published pre-clinical and clinical data. We aimed thereby to better understand the utility of treating MS with auto-HSCT and the feasibility of this procedure in Singapore. Methods: A Medline search was performed with the terms “haematopoietic stem cell transplantation”, “multiple sclerosis” and “autoimmune diseases” from 1996 to 2005. Both original papers and review articles were considered. Main Findings: The majority of publications were from Europe or the United States and most clinical series from single centres had relatively small numbers of patients. Worldwide, the number of patients reported has been less than 300 since 1997. Existing data support the feasibility and promise of this procedure and ongoing Phase III trials may serve to confirm this initial experience. Conclusion: Pre-clinical and early clinical data support the rationale for immunoablative therapy for autoimmune disorders. Auto-HSCT for severe MS is a feasible procedure and can be safely performed in centres with experience managing HSCT patients. Key words: Autoimmunity, Induction of tolerance, Progressive multiple sclerosis

Autologous hematopoietic stem cell transplantation for very active relapsing-remitting multiple sclerosis: report of two cases

Autologous hematopoietic stem cell transplantation (AHSCT) has been proposed as a rescue treatment in multiple sclerosis (MS) patients not responding to first- or second-line therapies. To date, most of the treated cases had a secondary progressive disease course. However, patients with high inflammatory activity, but no secondary progression of the disease, could be candidates to take greater advantage of AHSCT. In this paper, we report two cases with very active, relapsing-remitting (RR) MS, who underwent AHSCT, and obtained a dramatic resolution to disease activity.

Autologous hematopoietic stem cell transplantation for progressive multiple sclerosis: report of efficacy and safety at three yr of follow up in 21 patients

OBJECTIVE

To observe the efficacy and toxicity of autologous hematopoietic stem cell transplantation (HSCT) in progressive multiple sclerosis (PMS).

METHODOLOGY

Twenty-one patients with PMS were treated with autologous HSCT. Stem cells were mobilized with cyclophosphamide (CY) and granulocyte colony-stimulating factor. After conditioning regimen of CY and total body irradiation or BEAM, stem cells were reinfused. CD34+ cell selection of the graft was performed and anti-thymocyte globulin was given for T-cell depletion. The probabilities of confirmed progression-free survival and disease activity-free survival were used to assess the efficacy and the adverse experiences were recorded to detect the toxicities.

RESULTS

The median follow-up time was 42 (6-65) months. The probabilities of confirmed progression-free survival and the disease activity-free survival were 75% and 33.3%, respectively. The principal adverse events included allergy, infection, elevation of liver enzymes, transient neurologic deterioration and depression. Two patients died of severe pneumonia and varicella-zoster virus hepatitis, at 4.5 and 15 months post-transplant, respectively.

CONCLUSIONS

Autologous HSCT seems beneficial to PMS. However, more patients and longer follow up would be required to assess the risk/benefit ratio.

Autologous peripheral blood stem cell transplantation for severe multiple sclerosis

We describe the results of a clinical trial to evaluate the feasibility and toxicity of autologous hematopoietic stem cell transplantation (auto-HSCT) for patients with progressive multiple sclerosis (MS). Fifteen patients (all patients with secondary progressive MS) were enrolled. The median expanded disability status scale (EDSS) score at baseline was 6.0 (range, 4.5-7.5). Peripheral blood stem cells were obtained by leukapheresis after mobilization with granulocyte colony-stimulating factor. In 9 patients, CD34+ cell selection was performed with a CliniMACS cell selection system, and 6 patients accepted infusion of unmodified peripheral blood stem cells. The modified BEAM (carmustine, teniposide, cytarabine, and melphalan) was the sole conditioning regimen used. The adverse effects included infections, mucositis, transient hepatotoxicity, and diarrhea. Three patients had flares of neurologic deterioration during mobilization, 8 patients had the same manifestation during transplantation, and 2 patients had similar flares within 3 months of transplantation. Six patients experienced continuous neurologic improvement after transplantation, 5 patients experienced neurologic progression, and 4 patients had stabilization of their disease. The confirmed progression-free rate was 63.8% at 49 months. The results of lymphocyte purging were no better than for no purging. Auto-HSCT proved to be safe and beneficial for some MS patients. Further studies are needed to establish the merit of this procedure for MS patients.

Intense T cell depletion followed by autologous bone marrow transplantation for severe multiple sclerosis

BACKGROUND

Certain stem cell transplantation procedures might slow down inflammatory pathology in multiple sclerosis (MS).

AIMS

To halt disease progression in aggressive MS by a bone marrow transplantation (BMT) protocol aimed at maximum T cell suppression.

METHODS

Autologous BMT was performed in 14 patients with rapid secondary progressive MS (median EDSS score at baseline, 6; median disease duration, five years). To accomplish rigorous T cell ablation, a strong conditioning protocol was chosen--cyclophosphamide, total body irradiation, and antithymocyte globulin. To minimise the possibility of reinfusing mature T cells in the graft, bone marrow, not peripheral blood, was used as the CD34+ stem cell source.

RESULTS

Median follow up was 36 months (range, 7-36). Post-transplant haemopoietic recovery was successful in all patients. Early toxicity included Epstein-Barr virus related post-transplantation lymphoproliferative disorder. Longterm effects were development of antithyroid antibodies (three) and myelodysplastic syndrome (one). One patient died of progressive disease five years after transplantation. Treatment failure, defined by EDSS increase sustained for six months or more, was seen in nine patients and stabilisation or improvement in five. Other clinical parameters generally showed the same outcome. No gadolinium enhanced lesions were seen on post-treatment magnetic resonance imaging, in either cerebral or spinal cord scans. However, cerebrospinal fluid oligoclonal bands remained positive in most cases.

CONCLUSIONS

This strong immunosuppressive regimen did not prevent clinical progression in patients with aggressive secondary MS. The lack of efficacy, together with some serious side effects, does not favour the use of similar rigorous T cell depleting protocols in the future.

Multiple sclerosis: long-term remission after a high dose of cyclophosphamide

The objective of this case report is to document the possibility that immunoablative doses of cyclophosphamide may provide a long-term remission of multiple sclerosis (MS). We report the case of a 48-year-old woman with definite MS diagnosed in 1994 who has been in complete remission since a dose of 3800 mg of cyclophosphamide was accidentally given intravenously in early 1997. For 7 years there have been no signs of disease activity on history, physical examination, or on high-quality magnetic resonance imaging (MRI) with appropriate contrast-enhancement methodology. This case includes information on the possibility that less aggressive chemotherapy than that used with stem cell transplantation may be effective in the long-term control of MS.

Autologous haematopoietic-stem-cell transplantation for multiple sclerosis

Intense immunosuppression followed by autologous haematopoietic-stem-cell transplantation (HSCT) is being assessed as a potential treatment for patients with severe multiple sclerosis (MS). The treatment was developed from research that showed autologous HSCT was as effective as allogeneic HSCT in the treatment of experimental autoimmune encephalomyelitis. The treatment is thought to eradicate the defective immune system, and the infused haematopoietic stem cells reconstitute an immune system that is more tolerant to the nervous system. About 250 patients with MS have been treated with autologous HSCT as part of phase I and phase II open trials. Autologous HSCT seems feasible in MS and assessment with clinical and MRI measures suggests it induces a profound and long-lasting suppression of inflammation. The course of MS seems to be stabilised after autologous HSCT, especially in ambulatory patients with evidence of active disease. Autologous HSCT deserves further study in randomised controlled trials.

High-dose immunosuppression and autologous hematopoietic stem cell rescue for severe multiple sclerosis

Multiple sclerosis is a relatively common and seriously disabling disease of autoimmune pathogenesis, for which there is currently no cure. Available therapies include immunomodulating agents and standard-dose immunosuppressants, which may be helpful but are not curative. Recently, studies in animal models have indicated that control of autoimmune disease can be obtained by high-dose immunosuppression followed by hematopoietic stem cell transplantation (rescue). Autologous transplants for severe and refractory multiple sclerosis were proposed in 1997 and have been performed ever since in selected patients and in the context of phase I/II trials. To date, more than 200 patients have been treated worldwide, and similar results were obtained in different centers: high-dose therapy suppresses inflammation in the brain to a degree superior to any other conventional therapy and seems to delay significantly clinical disease progression. There is, however, a procedure-related mortality risk of 1.5-5%, requiring careful patient selection before transplant. The treatment should be reserved for patients having high chance of response, i.e., young patients with low disability scores but rapidly progressing disease, having inflammatory rather than neurodegenerative changes in the central nervous system. The mechanism of action of transplantation is unclear. The initial concept of immune ablation by high-dose therapy and reconstitution of normal immunity from transplant-derived lymphocyte progenitors has given way to the concept of "resetting" the immune system and of bringing the disease to a lower level of activity. One could also speculate on a tissue repair effect, given the ability of human hematopoietic stem cells to migrate also into the central nervous system. The clinical effect of transplantation remains to be demonstrated in a randomized study. The Autoimmune Disease Working Party of the European Group for Blood and Marrow Transplantation has launched such a trial, comparing transplantation to the currently best available therapy, i.e., mitoxantrone, and in about 5 years we should know whether transplantation offers more than the benefit of a transient immunosuppressive effect.

Autologous hemopoietic stem cell transplantation in the treatment of multiple sclerosis: rationale and clinical experience

Based on the encouraging results of transplantation in animals with experimental autoimmune encephalomyelitis (EAE), small-scale phase I/II trials of autologous hematopoietic stem cell transplantation (autoHSCT) were initiated in 1995 for the treatment of severe cases of multiple sclerosis (MS). More than 200 patients with treatment-resistant multiple sclerosis have been transplanted so far, mainly in Europe and the USA. The results of these studies appear promising in terms of impact on MRI disease parameters and, to a lesser extent, clinical stabilization or even improvement. Despite concerns raised by the morbidity and mortality noted in the initial pilot studies, a controlled, randomized, phase III trial of autoHSCT against the best currently available treatment, i.e., mitoxantrone, seems justified and is under way.

Haematopoietic stem cell transplantation for autoimmune disorders: the American perspective

The hypothesis that haematopoietic stem cell transplantation (HSCT) might be useful in treating refractory autoimmune diseases (AID) was suggested by studies in animal models and by the improvement of concurrent autoimmune diseases in patients who had undergone transplantation for haematological disorders. This concept has now been tested in a substantial number of phase I/II clinical trials of autologous HSCT. These early results are promising, even in patients who have failed on multiple standard therapies for AID. Transplantation-related toxicity has decreased with growing experience in the application of this procedure, better patient selection and the modification of treatment protocols. Randomized trials currently under way or under consideration should clarify the role of HSCT in patients with autoimmune disorders.

Stem cell transplantation for multiple sclerosis: What is the evidence?

Experimental and clinical observations have indicated that high-dose immunosuppression followed by autologous stem cell transplantation (ASCT) can induce remissions in severe, refractory, autoimmune diseases including multiple sclerosis (MS), a T cell-mediated autoimmune disorder against CNS myelin components, causing severe chronic disability. Control of the disease is unsatisfactory in most of the patients, especially those with rapidly evolving relapsing-remitting course and those with chronic progressive disease. The rationale for treating autoimmune diseases with ASCT is based on the immunosuppressive and immunomodulating effects of ASCT which may shift the immunological balance towards disease quiescence, a hypothesis supported by the results of ASCT in animal models of MS and by clinical observations in MS patients transplanted for concurrent malignancies. A number of phase I-II studies of ASCT in patients with active MS, conducted worldwide since 1995, and a comprehensive analysis of 85 patients, recently reported by the European Group for Blood and Marrow Transplantation (EBMT), have shown the feasibility of the method, a prominent anti-inflammatory effect on magnetic resonance imaging (MRI) disease, and a possible clinical benefit for active and refractory cases. The impact on MRI disease parameters appears superior with ASCT than with conventional therapies but the clinical results, in terms of stabilization of disease and prevention of disability, need to be validated in prospective, controlled trials. The procedure is also associated with a transplant-related mortality risk, of about 5% in high-risk cases, i.e., in older patients, those with high disability scores, those receiving strong myeloablative conditioning regimens and those undergoing intensive in vivo or ex vivo T cell-depletion. Therefore, it could be recommended for the treatment of a chronic, non-lethal, disease like MS only if it proved superior to standard therapies. A randomized trial is now launched by the EBMT to compare ASCT to mitoxantrone, currently regarded as one of the best available treatments, in properly selected patients having high chance of response at minimal mortality risk.

Hematopoietic stem cell transplantation for autoimmune diseases in developing countries: current status and future prospectives

In this paper we present preliminary results of hematopoietic stem cell transplantation for autoimmune diseases in Brazil and China. Chinese experience transplanting lupus is significant and the Brazilian experience with several autoimmune diseases is growing. We discuss peculiar conditions in developing countries which could affect the results, and future prospectives for the organization of phase III randomized trials in those countries.

Treatment of refractory myasthenia: "rebooting" with high-dose cyclophosphamide

Patients with myasthenia gravis (MG) who do not respond to conventional immunotherapeutic agents, or cannot tolerate their side effects, are considered "refractory." Ablation of the immune system followed by bone marrow transplant has been shown to cure experimental MG in rats. It is now known that immunoablative treatment with high-dose cyclophosphamide does not damage hematopoietic "stem cells," permitting repopulation of the immune system without bone marrow transplant. Recent evidence indicates that this treatment can induce durable remissions in autoimmune diseases. We treated three myasthenic patients, for whom treatment with thymectomy, plasmapheresis, and conventional immunotherapeutic agents failed, by using high-dose cyclophosphamide (50mg/kg/day intravenously for 4 days) followed by granulocyte colony stimulating factor. All three patients tolerated the treatment well and have had marked improvement in myasthenic weakness, permitting reduction of immunosuppressive medication to minimal levels. Acetylcholine receptor (AChR) antibody levels decreased in two AChR antibody-positive patients, and anti-MuSK antibody levels decreased in one "AChR antibody-negative" patient. The patients have been followed for up to 3.5 years, with no recurrence of symptoms. High-dose cyclophosphamide treatment appears to be an effective and safe treatment for selected patients with refractory MG. Further follow-up of these and additional patients will be needed to determine whether the benefit is durable.

Consenso expandido do BCTRIMS para o tratamento da esclerose múltipla: I. As evidências para o uso de imunossupressores, plasmaférese e transplante autólogo de células tronco

O tratamento da esclerose múltipla (EM) com imunossupressores teve início na década de 60. As observações laboratoriais e clínicas de que a doença tinha um caráter inflamatório induziu os clínicos a utilizarem medicamentos citostáticos e imunossupressores. Foram assim incorporados ao arsenal terapêutico da EM as drogas utilizadas em outras doenças inflamatórias sistêmicas como a artrite reumatóide e o lupus eritematoso sistêmico. As drogas imunossupressoras mais utilizadas são a ciclofosfamida, azatioprina e o metotrexate. A ciclosporina e a cladribina foram utilizadas mais recentemente para o controle da EM na forma recorrente-remitente (RR). O mitoxantrone foi aprovado pelo FDA em 2000 para as formas mais agressivas, tanto RR, como secundariamente progressiva (SP) ou primariamente progressiva (PP). Outras formas de tratamento como plasmaférese e transplante autólogo de células tronco (TACT), foram inseridas neste arsenal terapêutico com suas características específicas e para casos especiais.

Differentiation of multiple sclerosis subtypes: implications for treatment

There has been tremendous progress in the immunomodulatory treatment of multiple sclerosis (MS) during recent years. With the introduction of interferon-beta, glatiramer acetate and mitoxantrone (recently registered for MS in the US), there are at least three therapeutic strategies that have proven effective in large phase III studies. However, not all patients with MS respond well to treatment with these drugs. This may largely be a consequence of disease heterogeneity. From a clinical perspective, patients with different disease courses show different treatment responses. Patients with relapsing-remitting MS are more likely to respond to immunomodulatory therapy than those with a progressive disease course. Studies of patients with secondary progressive MS have yielded inconsistent results and, so far, there has been no positive phase III study of immunomodulatory therapy in patients with primary progressive MS. Pathological evidence indicates that subtyping based on clinical findings alone does not reflect actual disease heterogeneity. In a large series of biopsy and autopsy specimens, at least four subtypes could be identified with respect to oligodendrocyte/myelin pathology and immunopathology. As long as the only method of identifying subtypes of disease is histopathology, differential therapy will remain a future goal. Thus, there is an urgent need for in vivo markers of immunopathogenesis in an individual patient that would allow treatment to be specifically directed towards a given pathological focus. However, at least from a theoretical point of view, some therapeutic approaches appear very attractive. Plasmapheresis and/or intravenous immunoglobulins could most plausibly be the best approach for the immunopathological subtype of MS, which is characterised by antibody and complement deposition next to demyelinated axons, in order to remove antibodies. The subtype of MS that is associated with heavy macrophage activation, T cell infiltration and expression of inflammatory mediator molecules, including tumour necrosis factor-alpha, may be most likely to respond to immunomodulation with interferon-beta or glatiramer acetate. There are other subtypes of MS in which viral infection or oligodendrocyte degeneration, rather than autoimmunity, appear to play a role. It is possible that these could benefit from antiviral therapy, oligodendrocyte protection or oligodendrocyte transplantation, although therapies based on these latter approaches have yet to be developed.

Multiple sclerosis

Multiple sclerosis is the prototype inflammatory autoimmune disorder of the central nervous system and, with a lifetime risk of one in 400, potentially the most common cause of neurological disability in young adults. As with all complex traits, the disorder results from an interplay between as yet unidentified environmental factors and susceptibility genes. Together, these factors trigger a cascade of events, involving engagement of the immune system, acute inflammatory injury of axons and glia, recovery of function and structural repair, post-inflammatory gliosis, and neurodegeneration. The sequential involvement of these processes underlies the clinical course characterised by episodes with recovery, episodes leaving persistent deficits, and secondary progression. The aim of treatment is to reduce the frequency, and limit the lasting effects, of relapses, relieve symptoms, prevent disability arising from disease progression, and promote tissue repair. Despite limited success in each of these categories, everyone touched by multiple sclerosis looks for a better dividend from applying an improved understanding of the pathogenesis to clinical management.

Stem cell transplantation in multiple sclerosis: multiple choices and multiple challenges

Multiple sclerosis (MS) is generally considered as an autoimmune disease of the central nervous system. This concept has led to the idea that profound immunosuppression followed by transplantation of stem cell grafts would stop, or at least slow down, disease activity. Supported by the positive effects of hematopoietic stem cell transplantation (HSCT) on experimental autoimmune encephalomyelitis and by anecdotal reports on the beneficial effect of HSCT on MS patients with concomitant malignant disease, HSCT programs for MS have been initiated worldwide. At this stage, it is impossible to draw general conclusions from the preliminary data reported and therefore overenthusiastic expectations should be tempered. The follow-up periods are too short the groups are too small, the selected patients and protocols too heterogeneous, and publication bias on positive results cannot be excluded. However, there is ample evidence that HSCT is a technically feasible approach in MS, not more dangerous than in the hemato-oncological diseases. For every step in the HSCT procedure, there are many different options. The time has come for a systematic analysis of the safety and efficacy associated with the different methodologies.

Stem cell transplantation for autoimmune diseases

Much progress has been made in the field of haemopoietic stem cell transplants (HSCTs) for severe autoimmune disorders. Theoretical considerations, animal data and anecdotal evidence suggested some time ago that intensive immunoablation followed by autologous HSCT could restore normal immune reactivity in patients with severe autoimmune disorders. Based on a concept statement issued in 1995, two European societies, the European League Against Rheumatism (EULAR) and the European Group for Blood and Marrow Transplantation (EBMT) began collecting phase I/II trial data in an international collaborative network. Sufficient information from more than 350 patients allows a preliminary assessment with level three evidence. Autologous HSCTs can induce remissions in all disease categories tested so far. Remissions can be transient or durable. HSCTs are associated with significant morbidity and mortality. Treatment-related mortality (TRM) is near 10% at 1 year and is associated with the intensity of the conditioning and the stage of the disease at the time of transplant. Marked interdisease differences exist. There are few data available in haematological autoimmune diseases, more in systemic sclerosis (SSc), systemic lupus erythematosus (SLE), juvenile idiopathic arthritis (JIA) and multiple sclerosis (MS). Patient selection has been recognized as a crucial element from the phase I-II trials. Patients with advanced disease, severely compromised organ function or irreversible organ damage should not be considered as candidates for HSCT. Prospective randomized studies should now determine the value of HSCT compared to standard therapy. Such trials are ongoing for patients with systemic sclerosis (ASTIS trial--Autologous Stem Cell Transplantation International Scleroderma Trial) or are planned for patients with multiple sclerosis (ASTIMS trial--Autologous Stem Cell Transplantation International Multiple Sclerosis Trial) and rheumatoid arthritis (ASTIRA trial--Autologous Stem Cell Transplantation International Rheumatoid Arthritis Trial). More phase II data are needed for other indications such as SLE and JIA.

Stem cells in the aetiopathogenesis and therapy of rheumatic disease

Animal models of autoimmune disease and case reports of patients with these diseases who have been involved in bone marrow transplants have provided important data implicating the haemopoietic stem cell in rheumatic disease pathogenesis. Animal and human examples exist for both cure and transfer of rheumatoid arthritis, systemic lupus erythematosus (SLE) and other organ-specific diseases using allogeneic haemopoietic stem cell transplantation. This would suggest that the stem cell in these diseases is abnormal and could be cured by replacement of a normal stem cell although more in vitro data are required in this area. Given the morbidity and increased mortality in some patients with severe autoimmune diseases and the increasing safety of autologous haemopoietic stem cell transplantation (HSCT), pilot studies have been conducted using HSCT in rheumatic diseases. It is still unclear whether an autologous graft will cure these diseases but significant remissions have been obtained which have provided important data for the design of randomized trials of HSCT versus more conventional therapy. Several trials are now open to accrual under the auspices of the European Bone Marrow Transplant Group/European League Against Rheumatism (EBMT/EULAR) registry. Future clinical and laboratory research will need to document the abnormalities of the stem cell of a rheumatic patient because new therapies based on gene therapy or stem cell differentiation could be apllied to these diseases. With increasing safety of allogeneic HSCT it is not unreasonable to predict cure of some rheumatic diseases in the near future.

Kinetics of PBPC mobilization by cyclophosphamide, as compared with that by epirubicin/paclitaxel followed by G-CSF support: implications for optimal timing of PBPC harvest

BACKGROUND

Limited information is available on the mobilization kinetics of autologous PBPCs after induction with various chemotherapy regimens. With PBPC mobilization in patients with breast cancer used as a model for chemotherapy-induced PBPC recruitment, the kinetics of progenitor cells mobilized either with cyclophosphamide (CY) or epirubicin/paclitaxel (EPI-TAX) followed by the administration of G-CSF was compared.

STUDY DESIGN AND METHODS

The study included a total of 86 patients with breast cancer (stage II-IV) receiving either CY (n = 39) or EPI-TAX (n = 47), both followed by G-CSF support. The progenitor cell content in peripheral blood and apheresis components was monitored by flow cytometric enumeration of CD34+ cells. PBPC collection was started when the threshold of >20 x 10(6) CD34+ cells per L of peripheral blood was reached.

RESULTS

The PBPC collection was begun a median of 9 days after the administration of EPI-TAX followed by G-CSF support, as compared to a median of 13 days after mobilization with CY plus G-CSF. After treatment with CY, the total numbers of PBPCs peaked on Day 1 of apheresis, and they rapidly declined thereafter. In contrast, treatment with EPI-TAX followed by G-CSF administration led to a steady mobilization of CD34+ cells during leukapheresis. The difference in the mobilization patterns with CY and EPI-TAX resulted in a greater yield of CD34+ cells per L of processed blood volume. Compared to EPI-TAX, mobilization with CY required the overall processing of 30 percent less whole-blood volume to reach the target yield of > or = 10 x 10(6) CD34+ cells per kg of body weight. After a median of three apheresis procedures, however, both CY+G-CSF and EPI-TAX+G-CSF were equally effective in obtaining this target yield.

CONCLUSION

These results imply that specific PBPC mobilization as part of a given chemotherapy regimen should be taken into consideration before the planning of a PBPC harvest.

Autologous stem cell transplantation in progressive multiple sclerosis--an interim analysis of efficacy

Based on the good results of experimental transplantation in animal models of multiple sclerosis and of other autoimmune diseases, we have treated 24 patients suffering from chronic progressive multiple sclerosis with high-dose chemotherapy (BEAM regimen) followed by autologous blood stem cell rescue and antithymocyte globulin. Blood stem cells were mobilised with cyclophosphamide at 4g/m2 and G- (or GM-) CSF. In 9 cases, additional CD34+ cell-selection of the graft was performed. Here we update previously published results of this novel treatment, mainly with regard to clinical efficacy, as the median follow-up time has reached 40 months (range, 21-51). Infections were the principal toxicity early after the procedure, with death of a patient from aspergillosis 65 days post stem cell infusion. No serious late events occurred apart from a case of autoimmune thyroiditis that developed 11 months after transplant in a patient who had received a CD34+ cell-depleted graft. Mild and transient neurotoxicity was observed in 10 patients (42%), most probably associated with fever and infections. Eighteen patients (18/23; 78%) responded to the treatment, i.e., they were improved or stabilized, while five patients progressed, of which 4 had primary progressive disease. Of those improved or stabilised (18), 9 patients have maintained stable condition whereas 9 developed relapses or they slowly resumed progression, although their disability scores have not gotten worse than they were before transplantation. The probability of progression-free survival (compared to entry status) at 3 years is 92% for patients with secondary progressive disease and 39% for the primary progressive type. CD34+ cell-selection did not seem to yield better results except for a delay in progression or in relapse after transplantation. These results appear better than those achieved by any other treatment of progressive multiple sclerosis, including beta-interferon, but they need to be confirmed by other open or controlled studies in view of the well-known difficulty of judging objectively the effect of a treatment in patients with this disease.