We studied repeated cerebrospinal fluids of patients with Devic’s neuromyelitis optica (NMO) and multiple sclerosis (MS). Variations of oligoclonal bands (OBs) had opposite trends in the two groups. In MS, O Bs were detected in 399 of 411 patients (97%) and never disappeared. In NMO, O Bs were detected in three of 11 patients (27%) and always disappeared. The hypothesis that NMO and MS follow distinct patho genetic pathways is supported by our findings, which can be useful for the differentiatio n of NMO from MS.

To propose a simple tool for early prediction of unfavourable long term evolution of multiple sclerosis (MS). A Bayesian model allowed us to calculate, within the first year of disease and for each patient, the Bayesian Risk Estimate for MS (BREMS) score that represents the risk of reaching secondary progression (SP). The median BREMS scores were higher in 158 patients who reached SP within 10 years compared with 1087 progression free patients (0.69 vs 0.30; p<0.0001). The BREMS value was related to SP risk in the whole cohort (p<0.0001) and in the subgroup of 535 patients who had never been treated with immune therapies, thus reasonably representing the natural history of the disease (p<0.000001). The BREMS score may be useful both to identify patients who are candidates for early or for more aggressive therapies and to improve the design and analysis of clinical therapeutic trials and of observational studies.

Background: Some environmental factors have been already associated to increased risk of multiple sclerosis (MS), but it is plausible that additional factors might play a role.Objective: To investigate in MS patients the relationship between inflammatory activity, detected by brain magnetic resonance imaging (MRI) with gadolinium (Gd), and air pollution, namely, particulate matters with diameter less than 10 μm (PM₁₀).Methods: We analyzed from 52 remitting MS patients 226 brain MRIs, 34% with (Gd+MRI) and 66% without (Gd-MRI) T1-Gd-enhancing lesions. Daily recording of PM₁₀in the 30 days before MRI examination was obtained by monitors depending on the residence of subjects.Results: PM₁₀levels in the 5, 10, 15, 20, and 25 days before brain MRIs were higher (plus 16%, 21%, 24%, 25%, and 21%, respectively) with reference to Gd+MRI versus Gd-MRI. There was a significant association between Gd+MRI and PM₁₀levels ( p = 0.013), independent of immune therapies, smoker status, and season. In patients who had two repeated MRIs with opposite outcomes (Gd-MRI and Gd+MRI), PM₁₀levels were strongly higher in concurrence with Gd+MRI ( p < 0.0001).Conclusion: Our findings suggest that air pollution may be a risk factor for MS favoring inflammatory exacerbations.

Multiple Sclerosis (MS) displays a heterogeneous clinical onset and progression, which are mostly unpredictable, but demyelination of the central nervous system (CNS) leads to substantial deficits of sensory, motor, autonomic, and neurocognitive functions. Considering all genetic studies on MS, including the advanced genome-wide association studies, the risk linked to HLA alleles remains the highest among other susceptibility genetic variants. However, given the genetic variability of HLA alleles in different ethnic groups, we conducted a systematic review of reviews and meta-analyses aiming at summarizing all the results on the association between MS and HLA class II genes. We systematically searched meta-analyses and systematic reviews dealing with MS and HLA in all ethnicities. From 154 records, we included 5 articles collecting HLA data from 15,232 MS patients and 24,194 ethnically matched controls. DRB1∗15 (OR ranging from 1.39 in Chinese Han to 2.59 in Caucasians) and DQB1∗06:02 (OR ranging from 1.91 in Caucasians to 2.49 in Colombian) alleles confer an increased risk for MS transethnically (Caucasians, Chinese, South Americans, Carribeans, Middle Easterners, Japanese, and North Africans). DRB1∗01, DRB1∗09, DRB1∗11, DRB1∗12, and DRB1∗16 alleles were protective, in agreement with the type of amino-acidic (aa) residues (ranging from position 9 to 90) included in pockets 1, 4, 6, 7, and 9, which are most involved in peptide presentation. Changes in aa residues affect the capability of HLA molecules in binding myelin peptides. DQB1∗06:02 risk allele seems to be the most interesting target as humanized mice expressing only DQB1∗06:02 develop MS-like disease mediated by autoimmune reactions against myelin oligodendrocytic basic protein that stabilizes the myelin. Our summary of results from a high number of patients and controls suggests that allelic variants from both DQB1 and DRB1 genes are equally involved in MS susceptibility/protection transethnically.

Objective: Air pollution has been recently identified as a risk factor for multiple sclerosis. Aim of this study was to investigate the immunological mechanism underlying the clinical association between air pollution, namely exposure to particulate matter 10 (PM10), and inflammatory activity of multiple sclerosis (MS)Methods: Daily recording of PM10 was obtained by monitors depending on the residence of subjects. Expression of molecules involved in activation, adhesion, and migration of T lymphocytes were tested by flow cytometry in 57 MS patients and 19 healthy controls. We next assessed in vitro the effect of PM10 on expression of C-C chemokine receptors 6 (CCR6) by peripheral blood mononuclear cells (PBMCs), on cytokine production by monocyte-derived dendritic cells (mdDC), and on T cell polarization in PBMC/mdDC mixed cultures.Results: We identified a significant correlation between mean PM10 levels and expression of CCR6 CD4+ T circulating cells in MS patients. This was paralleled by the observation in vitro of a higher level of CCR6 expression on PBMC following treatment with increased doses of particulate matter. Moreover, in mdDC cultures, particulate matter induced the secretion by mdDC of Th17 polarizing IL1 beta, IL6, and IL23 and, in mdDC/PBMC mixed cultures, enhanced generation of IL17-producing T cells.Conclusions: Ex vivo and in vitro studies support the pro-inflammatory role of PM in MS, by upregulating expression of CCR6 on circulating CD4+ T cells and inducing in innate immune cells the production of Th17 polarizing cytokines. Therefore, we speculate that in MS respiratory exposure to PM10 may induce the production in the lung of autoreactive Th17 lymphocytes and boost their migratory properties through the blood-brain barrier.