Doralina G. Brum

Brazilian experience with two conditioning regimens in patients with multiple sclerosis: BEAM/horse ATG and CY/rabbit ATG

Studies have shown that autologous hematopoietic SCT (HSCT) can be used as an intensive immunosuppressive therapy to treat refractory patients and to prevent the progression of multiple sclerosis (MS). This is a prospective multicentric Brazilian MS trial comparing two conditioning regimens: BEAM/horse ATG and CY/rabbit ATG. Most (80.4%) of the 41 subjects in the study had the secondary progressive MS subtype and the mean age was 42 years. The baseline EDSS score in 58.5% of the subjects was 6.5 and 78% had a score of 6.0 or higher, respectively. The complication rate during the intra-transplantation period was 56% for all patients: 71.4% of the patients in the BEAM/hATG group and 40% in the CY/rATG group (P=0.04). Three subjects (7.5%) died of cardiac toxicity, sepsis and alveolar hemorrhage, all of them in the BEAM/ATG group. EFS was 58.54% for all patients: 47% in the BEAM/hATG group and 70% in the CY/rATG group (P=0.288). In conclusion, the CY/rATG regimen seems to be associated with similar outcome results, but presented less toxicity when compared with the BEAM/hATG regimen. Long-term follow-up would be required to fully assess the differences in therapeutic effectiveness between the two regimens.

Increased plasma levels of brain derived neurotrophic factor (BDNF) after multiple sclerosis relapse

Brain derived neurotrophic factor (BDNF) has been related to neuroprotection in a series of central nervous system diseases, although its role in multiple sclerosis (MS) was only partially investigated. In this work, we aimed to evaluate the plasma levels of BDNF from 29 MS patients and 24 control subjects. MS patients had decreased levels of BDNF in comparison with healthy controls. BDNF levels increased significantly after MS relapse. Our results provide some evidence for the involvement of BDNF in the pathogenesis of MS and suggest a role for this neurotrophin during the recovery of acute demyelinating inflammatory lesion.

miR-15a and 16-1 are downregulated in CD4+ T cells of multiple sclerosis relapsing patients.

ABSTRACT The pathology of relapsing–remitting multiple sclerosis (RR-MS) is largely attributed to activated autoreactive effector T lymphocytes. The influence of microRNAs on the immune response has been shown to occur in different pathways of lymphocyte differentiation and function. Here, the expression of the miRNAs miR-15a/16-1 in PBMC, CD4+, and CD8+ from RR-MS patients has been investigated. BCL2, a known miR-15a/16-1 target, has also been analyzed. The results have shown that miR-15a/16-1 is downregulated in CD4+ T cells, whereas BCL2 is highly expressed in RR-MS patients only. Our data suggest that miR-15a/16-1 can also modulate the BCL2 gene expression in CD4+ T cells from RR-MS patients, thereby affecting apoptosis processes.

Association of the HLA-DRB1⁎15 allele group and the DRB1⁎1501 and DRB1⁎1503 alleles with multiple sclerosis in White and Mulatto samples from Brazil

Multiple sclerosis (MS) is a multifactorial inflammatory disease that primarily affects the central nervous system. Genes and environmental factors probably interact in MS susceptibility and outcome; however, their roles have not been elucidated yet. The evaluation of the HLA-DRB1 gene in the Brazilian population is of particular interest in evidencing the behavior of HLA-DRB1 alleles in a highly admixed population inserted in an environment of low MS prevalence. The present results suggest that a given HLA-DRB1 allele may exhibit different behaviors, i.e. confer resistance or susceptibility, in response to the environmental and/or genetic (ethnic) backgrounds that characterize a sampled population.

Bone marrow mesenchymal stromal cells isolated from multiple sclerosis patients have distinct gene expression profile and decreased suppressive function compared with healthy counterparts.

Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease of the central nervous system, due to an immune reaction against myelin proteins. Multipotent mesenchymal stromal cells (MSCs) present immunosuppressive effects and have been used for the treatment of autoimmune diseases. In our study, gene expression profile and in vitro immunomodulatory function tests were used to compare bone marrow-derived MSCs obtained from MS patients, at pre- and postautologous hematopoietic stem cell transplantation (AHSCT) with those from healthy donors. Patient MSCs comparatively exhibited i) senescence in culture; ii) similar osteogenic and adipogenic differentiation potential; iii) decreased expression of CD105, CD73, CD44, and HLA-A/B/C molecules; iv) distinct transcription at pre-AHSCT compared with control MSCs, yielding 618 differentially expressed genes, including the downregulation of TGFB1 and HGF genes and modulation of the FGF and HGF signaling pathways; v) reduced antiproliferative effects when pre-AHSCT MSCs were cocultured with allogeneic T-lymphocytes; vi) decreased secretion of IL-10 and TGF-β in supernatants of both cocultures (pre- and post-AHSCT MSCs); and vii) similar percentages of regulatory cells recovered after MSC cocultures. The transcriptional profile of patient MSCs isolated 6 months posttransplantation was closer to pre-AHSCT samples than from healthy MSCs. Considering that patient MSCs exhibited phenotypic changes, distinct transcriptional profile and functional defects implicated in MSC immunomodulatory and immunosuppressive activity, we suggest that further MS clinical studies should be conducted using allogeneic bone marrow MSCs derived from healthy donors. We also demonstrated that treatment of MS patients with AHSCT does not reverse the transcriptional and functional alterations observed in patient MSCs.

Matrix metalloproteinase-9 genotypes and haplotypes are associated with multiple sclerosis and with the degree of disability of the disease

Multiple sclerosis (MS) is an autoimmune disease causing severe neurological disability. This study was carried out in order to determine whether the MMP-9 C(-1562)T and (CA)(13-25) polymorphisms are associated with MS. A total of 165 patients (92 whites/73 mulattos) and 191 controls (96 whites/95 mulattos) were enrolled in the study. While no difference in C(-1562)T polymorphism was observed between MS and healthy subjects, (CA)(n) genotypes and alleles were associated with MS. Moreover, the haplotypes are not associated with MS but seem to be relevant to the clinical status of MS. Thus the (CA)(n) polymorphism may contribute to MS susceptibility, but C(-1562)T and (CA)(n) haplotypes may modulate disease severity.

The impact of diagnostic criteria for neuromyelitis optica in patients with MS: a 10-year follow-up of the South Atlantic Project.

Background: It is recognized that there is a particular geographic and ethnic distribution of neuromyelitis optica (NMO) among Caucasian and non-Caucasian populations. Objective: To review the diagnoses of patients whom were enrolled in the South Atlantic Project, a Brazilian multiple sclerosis (MS) survey performed from 1995–1998, and to identify NMO and MS case frequencies. Methods: We reviewed the data from a 10-year follow-up of MS patients. To apply the current diagnostic criteria, the neurologists were asked to collect clinical and laboratory data from the medical records of study patients treated from 1999–2009. Results: The spectrum of inflammatory demyelinating disease in 322 patients (67% white; 33% African-Brazilian) was: 49 (15%) with NMO; 14 (4%) with NMO syndromes; 10 (3%) with acute disseminated encephalomyelitis (ADEM); one isolated tumefactive brain lesion; 249 (77%) with MS (151 with relapsing–remitting MS (RRMS), 70 with secondary progressive MS (SPMS) and 27 with primary progressive MS (PPMS)). Disability was more severe in NMO and PPMS. One-third of the NMO patients had died. Conclusions: The frequency of NMO was 6.8% in São Paulo and 20.5% in Rio de Janeiro, and mainly seen in persons of African descent, which strengthens the hypothesis of there being an ethnic association of this disease. We recommend that epidemiological studies on MS that were performed previously be reviewed again, to ensure more accurate diagnoses.

Evaluation of Serum Levels of Chemokines during Interferon-β Treatment in Multiple Sclerosis Patients

Background: The molecules that provide access to activated T cells in the CNS, including chemokines, have been considered to be a crucial step in the pathogenesis of multiple sclerosis (MS).Aims: In this study, we investigated serial serum chemokine levels in patients with relapsing-remitting MS over 1 year and the association of these chemokine levels with treatment regimens, lesions on MRI and patients’ characteristics.Methods: Serum CXCL9, CXCL10, CCL2, CCL4 and CCL5 levels were evaluated using ELISA every 2 months for a year in 28 healthy controls and 28 MS patients during their treatment with interferon (IFN)-β. Patients under-went MRI and were evaluated using the Expanded Disability Status Scale (EDSS) at the first and final evaluations.Results: CXCL10 serum levels were higher in MS patients compared with controls, were positively correlated with T2 lesions on MRI and were slightly increased during relapses. Treatment with IFNβ-1a or IFNβ-1b was associated with increased CXCL10 levels when evaluated more than 36 hours after subcutaneous injection. The CXCL9 levels were higher after MS relapse. There was significant variability in CCL4 and CCL5 levels in the serial evaluations, associated with gender and treatment. CCL2 levels were higher in treated MS patients than healthy controls, particularly among those patients with a stable form of the disease.Conclusion: Serum is a feasible resource for searching for an immunological marker in MS. Peripheral chemokine levels correlated in different ways with IFNβ therapy and with disease and patient characteristics.Clinical trial registration number: ISRCTN45526724.

European Ancestry Predominates in Neuromyelitis Optica and Multiple Sclerosis Patients from Brazil

Background Neuromyelitis optica (NMO) is considered relatively more common in non-Whites, whereas multiple sclerosis (MS) presents a high prevalence rate, particularly in Whites from Western countries populations. However, no study has used ancestry informative markers (AIMs) to estimate the genetic ancestry contribution to NMO patients. Methods Twelve AIMs were selected based on the large allele frequency differences among European, African, and Amerindian populations, in order to investigate the genetic contribution of each ancestral group in 236 patients with MS and NMO, diagnosed using the McDonald and Wingerchuck criteria, respectively. All 128 MS patients were recruited at the Faculty of Medicine of Ribeirão Preto (MS-RP), Southeastern Brazil, as well as 108 healthy bone marrow donors considered as healthy controls. A total of 108 NMO patients were recruited from five Neurology centers from different Brazilian regions, including Ribeirão Preto (NMO-RP). Principal Findings European ancestry contribution was higher in MS-RP than in NMO-RP (78.5% vs. 68.7%) patients. In contrast, African ancestry estimates were higher in NMO-RP than in MS-RP (20.5% vs. 12.5%) patients. Moreover, principal component analyses showed that groups of NMO patients from different Brazilian regions were clustered close to the European ancestral population. Conclusions Our findings demonstrate that European genetic contribution predominates in NMO and MS patients from Brazil.

Immunological correlates of favorable long-term clinical outcome in multiple sclerosis patients after autologous hematopoietic stem cell transplantation

High dose immunosuppression followed by autologous hematopoietic stem cell transplantation (AHSCT) induces prolonged clinical remission in multiple sclerosis (MS) patients. However, how patient immune profiles are associated with clinical outcomes has not yet been completely elucidated. In this study, 37 MS patients were assessed for neurological outcomes, thymic function and long-term immune reconstitution after AHSCT. Patients were followed for a mean (SD) of 68.5 (13.9) months post-transplantation and were retrospectively clustered into progression- and non-progression groups, based on Expanded Disease Status Scale (EDSS) outcomes at last visit. After AHSCT, both patient groups presented increased regulatory T-cell subset counts, early expansion of central- and effector-memory CD8(+)T-cells and late thymic reactivation. However, the non-progression group presented early expansion of PD-1(+)CD8(+)T-cells and of PD-1-expressing CD19(+) B-cells. Here, we suggest that along with increased numbers of regulatory T-cell subsets, PD-1 inhibitory signaling is one possible immunoregulatory mechanism by which AHSCT restores immune tolerance in MS patients.