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

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

NK Cells and Innate-Like T Cells After Autologous Hematopoietic Stem Cell Transplantation in Multiple Sclerosis.

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system, in which autoreactive T and B cells play important roles. Other lymphocytes such as NK cells and innate-like T cells appear to be involved as well. To name a few examples, CD56bright NK cells were described as an immunoregulatory NK cell subset in MS while innate-like T cells in MS were described in brain lesions and with proinflammatory signatures. Autologous hematopoietic stem cell transplantation (aHSCT) is a procedure used to treat MS. This procedure includes hematopoietic stem/progenitor cell (HSPC) mobilization, then high-dose chemotherapy combined with anti-thymocyte globulin (ATG) and subsequent infusion of the patients own HSPCs to reconstitute a functional immune system. aHSCT inhibits MS disease activity very effectively and for long time, presumably due to elimination of autoreactive T cells. Here, we performed multidimensional flow cytometry experiments in peripheral blood lymphocytes of 27 MS patients before and after aHSCT to address its potential influence on NK and innate-like T cells. After aHSCT, the relative frequency and absolute numbers of CD56bright NK cells rise above pre-aHSCT levels while all studied innate-like T cell populations decrease. Hence, our data support an enhanced immune regulation by CD56bright NK cells and the efficient reduction of proinflammatory innate-like T cells by aHSCT in MS. These observations contribute to our current understanding of the immunological effects of aHSCT in MS.

Nine-year follow up after hematopoietic stem cell transplantation in five multiple sclerosis patients.

Multiple sclerosis (MS) is an immune-mediated disease of the central nervous system. Its treatment has focused on inflammation control as early as possible to avoid disability. Autologous hematopoietic stem cell transplantation (AHSCT) has been used for treating MS since 1996, with recent decisive results regarding benefits in long-term efficacy. Five patients followed up at an MS center in Belo Horizonte, Brazil, who had relapsing-remitting MS with high disease activity, underwent AHSCT between 2009 and 2011. They were evaluated clinically, with magnetic resonance imaging, and by the EDSS every six months after transplantation, up to July 2018. The patients were four women and one man, with ages ranging from 25-50 years, and time since disease onset ranging from 4-17 years at the time of the procedure. Four patients improved, one patient was stabilized, and all patients were free of disease activity after 5-9 years. Through improving patient selection and decreasing the time from disease onset, AHSCT could stop epitope spreading and disease progression. Despite multiple other therapeutic choices being approved for relapsing-remitting MS, AHSCT continues to be a treatment to consider for aggressive MS disease.

Nine-year follow up after hematopoietic stem cell transplantation in five multiple sclerosis patients / Nove anos de seguimento após transplante autólogo de células tronco hematopoiéticas em cinco pacientes com esclerose múltipla

ABSTRACT Multiple sclerosis (MS) is an immune-mediated disease of the central nervous system. Its treatment has focused on inflammation control as early as possible to avoid disability. Autologous hematopoietic stem cell transplantation (AHSCT) has been used for treating MS since 1996, with recent decisive results regarding benefits in long-term efficacy. Five patients followed up at an MS center in Belo Horizonte, Brazil, who had relapsing-remitting MS with high disease activity, underwent AHSCT between 2009 and 2011. They were evaluated clinically, with magnetic resonance imaging, and by the EDSS every six months after transplantation, up to July 2018. The patients were four women and one man, with ages ranging from 25-50 years, and time since disease onset ranging from 4-17 years at the time of the procedure. Four patients improved, one patient was stabilized, and all patients were free of disease activity after 5-9 years. Through improving patient selection and decreasing the time from disease onset, AHSCT could stop epitope spreading and disease progression. Despite multiple other therapeutic choices being approved for relapsing-remitting MS, AHSCT continues to be a treatment to consider for aggressive MS disease.

RESUMO A esclerose múltipla é uma doença imunomediada do sistema nervoso central. Seu tratamento tem sido focado no controle da inflamação o mais cedo possível para evitar incapacidade. O transplante autólogo de células tronco hematopoiéticas (TACTH) vem sendo usado para tratar esclerose múltipla desde 1996, e recentes resultados foram decisivos a respeito do benefício na eficácia a longo prazo. Cinco pacientes seguidos num centro de esclerose múltipla de Belo Horizonte, Brasil, que apresentavam forma clínica remitente recorrente com alta atividade de doença foram submetidos a esse tratamento de 2009 a 2011. Após o transplante foram avaliados clinicamente e com ressonância magnética, e escala de EDSS, a cada seis meses até julho de 2018. Os pacientes eram quatro mulheres e um homem, com idade entre 25 e 50 anos e tempo de doença variando de 4 a 17 anos na época do procedimento. Quatro pacientes melhoraram após a primeira avaliação e um manteve-se estável. Todos os pacientes permaneceram sem evidência de doença clínica ou radiológica de 5 a 9 anos após. Com uma seleção cada vez mais criteriosa de pacientes o TACTH pode interromper a disseminação do epítopo e controlar a progressão da doença. Apesar de várias outras opções terapêuticas aprovadas para esclerose múltipla o TACTH continua a ser uma forma de tratamento a ser considerada em casos de doença muito agressiva.

Efficacy and Safety of Extracranial Vein Angioplasty in Multiple Sclerosis: A Randomized Clinical Trial.

Importance: Chronic cerebrospinal venous insufficiency (CCSVI) is characterized by restricted venous outflow from the brain and spinal cord. Whether this condition is associated with multiple sclerosis (MS) and whether venous percutaneous transluminal angioplasty (PTA) is beneficial in persons with MS and CCSVI is controversial. Objective: To determine the efficacy and safety of venous PTA in patients with MS and CCSVI. Design, Setting, and Participants: We analyzed 177 patients with relapsing-remitting MS; 62 were ineligible, including 47 (26.6%) who did not have CCSVI on color Doppler ultrasonography screening. A total of 115 patients were recruited in the study timeframe. All patients underwent a randomized, double-blind, sham-controlled, parallel-group trial in 6 MS centers in Italy. The trial began in August 2012 and concluded in March 2016; data were analyzed from April 2016 to September 2016. The analysis was intention to treat. Interventions: Patients were randomly allocated (2:1) to either venous PTA or catheter venography without venous angioplasty (sham). Main Outcomes and Measures: Two primary end points were assessed at 12 months: (1) a composite functional measure (ie, walking control, balance, manual dexterity, postvoid residual urine volume, and visual acuity) and (2) a measure of new combined brain lesions on magnetic resonance imaging, including the proportion of lesion-free patients. Combined lesions included T1 gadolinium-enhancing lesions plus new or enlarged T2 lesions. Results: Of the included 115 patients with relapsing-remitting MS, 76 were allocated to the PTA group (45 female [59%]; mean [SD] age, 40.0 [10.3] years) and 39 to the sham group (29 female [74%]; mean [SD] age, 37.5 [10.6] years); 112 (97.4%) completed follow-up. No serious adverse events occurred. Flow restoration was achieved in 38 of 71 patients (54%) in the PTA group. The functional composite measure did not differ between the PTA and sham groups (41.7% vs 48.7%; odds ratio, 0.75; 95% CI, 0.34-1.68; P = .49). The mean (SD) number of combined lesions on magnetic resonance imaging at 6 to 12 months were 0.47 (1.19) in the PTA group vs 1.27 (2.65) in the sham group (mean ratio, 0.37; 95% CI, 0.15-0.91; P = .03: adjusted P = .09) and were 1.40 (4.21) in the PTA group vs 1.95 (3.73) in the sham group at 0 to 12 months (mean ratio, 0.72; 95% CI, 0.32-1.63; P = .45; adjusted P = .45). At follow-up after 6 to 12 months, 58 of 70 patients (83%) in the PTA group and 22 of 33 (67%) in the sham group were free of new lesions on magnetic resonance imaging (odds ratio, 2.64; 95% CI, 1.11-6.28; P = .03; adjusted P = .09). At 0 to 12 months, 46 of 73 patients (63.0%) in the PTA group and 18 of 37 (49%) in the sham group were free of new lesions on magnetic resonance imaging (odds ratio, 1.80; 95% CI, 0.81-4.01; P = .15; adjusted P = .30). Conclusion and Relevance: Venous PTA has proven to be a safe but largely ineffective technique; the treatment cannot be recommended in patients with MS. Trial Registration: clinicaltrials.gov Identifier: NCT01371760.

Long-term follow-up more than 10 years after HSCT: a monocentric experience.

BACKGROUND: Autologous hematopoietic stem cell transplantation (aHSCT) is used in aggressive relapsing and progressive multiple sclerosis (MS). The multicentre studies and case series reported have relatively short follow-up. AIM: To evaluate long-term effect and safety of HSCT in MS. MATERIALS AND METHODS: Patients referred to the MS centre of Cagliari and undergoing HSCT were included. Variations in relapses and EDSS before and after HSCT were evaluated by Wilcoxon test. A descriptive analysis was made for other clinical data. RESULTS: Nine patients (female 6, males 3; 5 relapsing-remitting, 2 secondary progressive, 1 primary progressive, and 1 progressive relapsing) performed HSCT (1999-2006). The median follow-up was 11 years (11-18). Eight patients underwent aHSCT, seven using a low intensity conditioning regimen, and one an intermediate intensity. The primary progressive underwent allogeneic HSCT, due to onco hematological disease. The relapses number decreased in the 2 years following the procedure compared to the two preceding years (p = 0.041). New relapses or disease progressions were observed after a range of 7 (low intensity regimen)-118 (intermediate intensity) months. At last follow-up, the EDSS was stable in two patients, improved in two, and worse in five (maximum 2 EDSS in one patient). Six patients showed new lesions, and seven gadolinium-enhancing on brain MRI after a mean of 23.3 and 19.8 months, respectively. Two serious adverse events were reported: melanoma, and progressive multifocal leukoencephalopathy. CONCLUSIONS AND DISCUSSION: Our results confirm in a long follow-up the efficacy of HSCT in reducing relapses and disability progression. The risk/benefit profile is better for intermediate intensity regimens.

Patient-Reported Benefits of Extracranial Venous Therapy: British Columbia CCSVI Registry.

Objective Chronic cerebrospinal venous insufficiency (CCSVI) has been hypothesized to be a risk factor for multiple sclerosis (MS). Venoplasty has been proposed as a treatment for CCSVI. The aim of our study was to gain a better understanding of the "real-world" safety and longitudinal effectiveness of venoplasty Methods: British Columbia residents who self-reported having had venoplasty and consented to participate in the study were interviewed and followed for up to 24 months post-therapy using standardized structured questionnaires Results: Participants reported procedure-related complications (11.5%) and complications within the first month after the procedure (17.3%). Initially, more than 40% of participants perceived that the venoplasty had had positive effects on their health conditions, such as fatigue, numbness, balance, concentration/memory and mobility. However, this improvement was not maintained over time Conclusions: Follow-up patient-reported outcomes indicated that the initial perception of the positive impact of venoplasty on the health conditions of MS patients was not sustained over time. In addition, venoplasty was not without associated morbidity.

High-dose immunosuppressive therapy and autologous hematopoietic cell transplantation for relapsing-remitting multiple sclerosis (HALT-MS): a 3-year interim report.

IMPORTANCE: Most patients with relapsing-remitting (RR) multiple sclerosis (MS) who receive approved disease-modifying therapies experience breakthrough disease and accumulate neurologic disability. High-dose immunosuppressive therapy (HDIT) with autologous hematopoietic cell transplant (HCT) may, in contrast, induce sustained remissions in early MS. OBJECTIVE: To evaluate the safety, efficacy, and durability of MS disease stabilization through 3 years after HDIT/HCT. DESIGN, SETTING, AND PARTICIPANTS: Hematopoietic Cell Transplantation for Relapsing-Remitting Multiple Sclerosis (HALT-MS) is an ongoing, multicenter, single-arm, phase 2 clinical trial of HDIT/HCT for patients with RRMS who experienced relapses with loss of neurologic function while receiving disease-modifying therapies during the 18 months before enrolling. Participants are evaluated through 5 years after HCT. This report is a prespecified, 3-year interim analysis of the trial. Thirty-six patients with RRMS from referral centers were screened; 25 were enrolled. INTERVENTIONS: Autologous peripheral blood stem cell grafts were CD34+ selected; the participants then received high-dose treatment with carmustine, etoposide, cytarabine, and melphalan as well as rabbit antithymocyte globulin before autologous HCT. MAIN OUTCOMES AND MEASURES: The primary end point of HALT-MS is event-free survival defined as survival without death or disease activity from any one of the following outcomes: (1) confirmed loss of neurologic function, (2) clinical relapse, or (3) new lesions observed on magnetic resonance imaging. Toxic effects are reported using National Cancer Institute Common Terminology Criteria for Adverse Events. RESULTS: Grafts were collected from 25 patients, and 24 of these individuals received HDIT/HCT. The median follow-up period was 186 weeks (interquartile range, 176-250) weeks). Overall event-free survival was 78.4% (90% CI, 60.1%-89.0%) at 3 years. Progression-free survival and clinical relapse-free survival were 90.9% (90% CI, 73.7%-97.1%) and 86.3% (90% CI, 68.1%-94.5%), respectively, at 3 years. Adverse events were consistent with expected toxic effects associated with HDIT/HCT, and no acute treatment-related neurologic adverse events were observed. Improvements were noted in neurologic disability, quality-of-life, and functional scores. CONCLUSIONS AND RELEVANCE: At 3 years, HDIT/HCT without maintenance therapy was effective for inducing sustained remission of active RRMS and was associated with improvements in neurologic function. Treatment was associated with few serious early complications or unexpected adverse events.

The omohyoid muscle entrapment of the internal jugular vein. A still unclear pathogenetic mechanism.

OBJECTIVES: To evaluate the role of the omohyoid muscle anatomic variants as a possible reversible cause of internal jugular vein extrinsic compression. METHOD: We describe a chronic cerebro-spinal venous insufficiency patient, who presented a omohyoid muscle entrapment of the internal jugular vein, confirmed by both magnetic resonance venography and ultrasound investigation. A omohyoid muscle surgical transection together with a patch angioplasty was performed. RESULTS: The surgical procedure led to both IJV flow restoration and neurological improvement. CONCLUSIONS: The omohyoid muscle compression on the internal jugular vein seems to be a possible cause of venous obstruction, but several anatomical and patho-physiological aspects need further investigations. Such picture might cause balloon venous angioplasty inefficacy and needs to be preoperatively considered.

T-cell responses after haematopoietic stem cell transplantation for aggressive relapsing-remitting multiple sclerosis.

Autologous haematopoietic stem cell transplantation (HSCT) for relapsing-remitting multiple sclerosis is a potentially curative treatment, which can give rise to long-term disease remission. However, the mode of action is not yet fully understood. The aim of the study was to evaluate similarities and differences of the CD4(+) T-cell populations between HSCT-treated patients (n = 12) and healthy controls (n = 9). Phenotyping of memory T cells, regulatory T (Treg) cells and T helper type 1 (Th1) and type 17 (Th17) cells was performed. Further, T-cell reactivity to a tentative antigen, myelin oligodendrocyte glycoprotein, was investigated in these patient populations. Patients treated with natalizumab (n = 15) were included as a comparative group. White blood cells were analysed with flow cytometry and T-cell culture supernatants were analysed with magnetic bead panel immunoassays. HSCT-treated patients had similar levels of Treg cells and of Th1 and Th17 cells as healthy subjects, whereas natalizumab-treated patients had lower frequencies of Treg cells, and higher frequencies of Th1 and Th17 cells. Cells from HSCT-treated patients cultured with overlapping peptides from myelin oligodendrocyte glycoprotein produced more transforming growth factor-ß1 than natalizumab-treated patients, which suggests a suppressive response. Conversely, T cells from natalizumab-treated patients cultured with those peptides produced more interleukin-17 (IL-17), IL-1 and IL-10, indicating a Th17 response. In conclusion, we demonstrate circumstantial evidence for the removal of autoreactive T-cell clones as well as development of tolerance after HSCT. These results parallel the long-term disease remission seen after HSCT.

Changes of cine cerebrospinal fluid dynamics in patients with multiple sclerosis treated with percutaneous transluminal angioplasty: a case-control study.

PURPOSE: To investigate characteristics of cine phase contrast-calculated cerebrospinal fluid (CSF) flow and velocity measures in patients with relapsing-remitting (RR) multiple sclerosis (MS) receiving standard medical treatment who had been diagnosed with chronic cerebrospinal venous insufficiency (CCSVI) and underwent percutaneous transluminal angioplasty (PTA). MATERIALS AND METHODS: This case-controlled, magnetic resonance (MR) imaging-blinded study included 15 patients with RR MS who presented with significant stenoses (≥50% lumen reduction on catheter venography) in the azygous or internal jugular veins. Eight patients underwent PTA in addition to medical therapy immediately following baseline assessments (case group) and seven had delayed PTA after 6 months of medical therapy alone (control group). CSF flow and velocity measures were quantified over 32 phases of the cardiac cycle by a semiautomated method. Outcomes were compared between groups at baseline and at 6 and 12 months of the study by mixed-effect model analysis. RESULTS: At baseline, no significant differences in CSF flow or velocity measures were detected between groups. At month 6, significant improvement in flow (P<.001) and velocity (P = .013) outcomes were detected in the immediate versus the delayed group, and persisted to month 12 (P = .001 and P = .021, respectively). Within-group flow comparisons from baseline to follow-up showed a significant increase in the immediate group (P = .033) but a decrease in the delayed group (P = .024). Altered CSF flow and velocity measures were associated with worsening of clinical and MR outcomes in the delayed group. CONCLUSIONS: PTA in patients with MS with CCSVI increased CSF flow and decreased CSF velocity, which are indicative of improved venous parenchyma drainage.

Efficacy and safety of venous angioplasty of the extracranial veins for multiple sclerosis. Brave dreams study (brain venous drainage exploited against multiple sclerosis): study protocol for a randomized controlled trial.

BACKGROUND: Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system with a disabling progressive course. Chronic cerebrospinal venous insufficiency (CCSVI) has recently been described as a vascular condition characterized by restricted venous outflow from the brain, mainly due to blockages of the internal jugular and azygos veins. Despite a wide variability among studies, it has been found to be associated with MS. Data from a few small case series suggest possible improvement of the clinical course and quality of life by performing percutaneous balloon angioplasty (PTA) of the stenotic veins. STUDY DESIGN AND METHODS: This is a multicenter, randomized, parallel group, blinded, sham-controlled trial to assess the efficacy and safety of PTA. Participants with relapsing remitting MS or secondary progressive MS and a sonographic diagnosis of CCSVI will be enrolled after providing their informed consent. Each participant will be centrally randomized to receive catheter venography and PTA or catheter venography and sham PTA. Two primary end points with respect to efficacy at 12 months are (1) a combined end point obtained through the integration of five functional indicators, walking, balance, manual dexterity, bladder control, and visual acuity, objectively measured by instruments; and (2) number of new brain lesions measured by T2-weighted MRI sequences. Secondary end points include annual relapse rate, change in Expanded Disability Status Scale score, proportion of patients with zero, one or two, or more than two relapses; fatigue; anxiety and depression; general cognitive state; memory/attention/calculus; impact of bladder incontinence; and adverse events. Six hundred seventy-nine patients will be recruited. The follow-up is scheduled at 12 months. Patients, treating neurologists, trained outcome assessors, and the statistician in charge of data analysis will be masked to the assigned treatment. DISCUSSION: The study will provide an answer regarding the efficacy of PTA on patients' functional disability in balance, motor, sensory, visual and bladder function, cognitive status, and emotional status, which are meaningful clinical outcomes, beyond investigating the effects on inflammation. In fact, an important part of patients' expectations, sustained and amplified by anecdotal data, has to do precisely with these functional aspects. TRIAL REGISTRATION: Clinicaltrials.gov NCT01371760.

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

BACKGROUND: Over recent years numerous patients with severe forms of multiple sclerosis (MS) refractory to conventional therapies have been treated with intense immunosuppression followed by autologous haematopoietic stem cell transplantation (AHSCT). The clinical outcome and the toxicity of AHSCT can be diverse, depending on the various types of conditioning protocols and on the disease phase. OBJECTIVES: To report the Italian experience on all the consecutive patients with MS treated with AHSCT with an intermediate intensity conditioning regimen, named BEAM/ATG, in the period from 1996 to 2008. METHODS: Clinical and magnetic resonance imaging outcomes of 74 patients were collected after a median follow-up period of 48.3 (range = 0.8-126) months. RESULTS: Two patients (2.7%) died from transplant-related causes. After 5 years, 66% of patients remained stable or improved. Among patients with a follow-up longer than 1 year, eight out of 25 subjects with a relapsing-remitting course (31%) had a 6-12 months confirmed Expanded Disability Status Scale improvement > 1 point after AHSCT as compared with one out of 36 (3%) patients with a secondary progressive disease course (p = 0.009). Among the 18 cases with a follow-up longer than 7 years, eight (44%) remained stable or had a sustained improvement while 10 (56%), after an initial period of stabilization or improvement with median duration of 3.5 years, showed a slow disability progression. CONCLUSIONS: This study shows that AHSCT with a BEAM/ATG conditioning regimen has a sustained effect in suppressing disease progression in aggressive MS cases unresponsive to conventional therapies. It can also cause a sustained clinical improvement, especially if treated subjects are still in the relapsing-remitting phase of the disease.

FOXP3 gene expression in multiple sclerosis patients pre- and post mesenchymal stem cell therapy.

Multiple Sclerosis (MS) is an inflammatory demyelinating and neurodegenerative disorder of the central nervous system (CNS), which mainly affects young adults. Activated T lymphocytes promote the neuro-inflammatory cascade of MS by secreting pro-inflammatory cytokines and play a significant role in its pathogenesis. T lymphocytes may trigger the inflammation, which in turn leads to axonal loss and neurodegeneration observed in the course of MS. Currently, there is no cure for MS, however, one of the most promising neuroprotective research tools consists of the use of bone marrow derived mesenchymal stem cells (MSC). This method promotes immune system regulation and possibly induces neurological repair and re-myelination of the damaged axons. Recent studies have shown that MSC exert an immune regulatory function and induce T regulatory-cell proliferation, therefore, it may serve as a potentially useful treatment for immune-mediated diseases such as MS. In this pilot study a group of MS patients underwent MSC therapy and we assayed the expression of an X-linked transcription factor, FoxP3, as a specific marker of T Regulatory cells in peripheral blood, prior to and after the treatment. Using q RT-PCR for measurement of expression of FoxP3 by peripheral blood mononuclear cells, we found that in all subjects, except for one, the expression of FoxP3 at 6 months after intrathecal injection of MSC was significantly higher than the levels prior to treatment. Such significant enhanced expression of FoxP3 associated with clinical stability. Findings from this pilot study further support the potential of bone marrow derived MSC for treatment of MS patients.

Safety and feasibility of autologous bone marrow cellular therapy in relapsing-progressive multiple sclerosis.

In this phase I study, we assessed the safety and feasibility of intravenous, autologous bone marrow (BM) cell therapy, without immunosuppressive preconditioning, in six patients with clinically definite, relapsing-progressive multiple sclerosis (MS). Assessment of efficacy was a secondary objective and employed clinical disability rating scales, multimodal evoked potential (MMEP) recordings, and magnetic resonance imaging (MRI) scans. Cells were harvested, filtered and infused intravenously in a day-case procedure that was well tolerated by patients and was not associated with any serious adverse events (AEs). Over a period of 12 months after the therapy, clinical disability scores showed either no change (Extended Disability Status Score, EDSS) or improvement (MS impact scale-29, MSIS-29), and MMEPs showed neurophysiological improvement. MRI scans did not show any significant changes over a post-therapy period of 3 months. The lack of serious adverse effects and the suggestion of a beneficial effect in this small sample of patients with progressive disease justify conducting a larger phase II/III study to make a fuller assessment of the efficacy of mobilization of autologous BM in patients with MS.

Surgical excision of CNS-draining lymph nodes reduces relapse severity in chronic-relapsing experimental autoimmune encephalomyelitis.

Despite lack of classical lymphatic vessels in the central nervous system (CNS), cells and antigens do reach the CNS-draining lymph nodes. These lymph nodes are specialized to mediate mucosal immune tolerance, but can also generate T- and B-cell immunity. Their role in multiple sclerosis and experimental autoimmune encephalomyelitis (EAE) therefore remains elusive. We hypothesized that drainage of CNS antigens to the CNS-draining lymph nodes is vital for the recurrent episodes of CNS inflammation. To test this, we surgically removed the superficial cervical lymph nodes, deep cervical lymph nodes, and the lumbar lymph nodes prior to disease induction in three mouse EAE models, representing acute, chronic, and chronic-relapsing EAE. Excision of the CNS-draining lymph nodes in chronic-relapsing EAE reduced and delayed the relapse burden and EAE pathology within the spinal cord, which suggests initiation of CNS antigen-specific immune responses within the CNS-draining lymph nodes. Indeed, superficial cervical lymph nodes from EAE-affected mice demonstrated proliferation against the immunizing peptide, and the deep cervical lymph nodes, lumbar lymph nodes, and spleen demonstrated additional proliferation against other myelin antigen epitopes. This indicates that intermolecular epitope spreading occurs and that CNS antigen-specific immune responses are differentially generated within the different CNS-draining lymphoid organs. Proliferation of splenocytes from lymphadenectomized and sham-operated mice against the immunizing peptide was similar. These data suggest a role for CNS-draining lymph nodes in the induction of detrimental immune responses in EAE relapses, and conclusively demonstrate that the tolerance-inducing capability of cervical lymph nodes is not involved in EAE.