Ernesto Roldán

Intrathecal synthesis of oligoclonal IgM against myelin lipids predicts an aggressive disease course in MS

Oligoclonal IgM bands restricted to cerebrospinal fluid are an unfavorable prognostic marker in MS, the most common demyelinating disease of the CNS. We have attempted to identify the B cell subpopulation responsible for oligoclonal IgM secretion and the specificity of these bands. In addition, we explored the relationship between specificity and disease evolution. Intrathecal B cell subpopulations present in 29 MS patients with oligoclonal IgM bands and 52 without them were analyzed. A considerable increase in CD5(+) B lymphocytes was found in patients with oligoclonal IgM bands. These cells mostly secrete IgM antibodies recognizing nonproteic molecules. We also studied whether oligoclonal IgM bands present in cerebrospinal fluid of 53 MS patients were directed against myelin lipids. This was the case in most patients, with phosphatidylcholine being the most frequently recognized lipid. Disease course of 15 patients with oligoclonal IgM against myelin lipids and 33 patients lacking them was followed. Patients with anti-lipid IgM suffered a second relapse earlier, had more relapses, and showed increased disability compared with those without anti-lipid IgM. The presence of intrathecal anti-myelin lipid IgM antibodies is therefore a very accurate predictor of aggressive evolution in MS.

Intrathecal IgM synthesis is a prognostic factor in multiple sclerosis.

Intrathecal IgM synthesis (ITMS) predicts a worse evolution in the first stages of multiple sclerosis (MS). The aim of this study was the follow‐up of a group of relapsing‐remitting MS patients for a longer time to evaluate whether the ITMS implies a poor prognosis. Oligoclonal IgM bands were performed in 29 MS patients followed up from 5 to 16 years. Time to conversion to secondary‐progressive MS (SPMS), time elapsed to reach a disability of 6 in the Expanded Disability Status Scale (EDSS), percentage of patients with a benign MS, and changes in EDSS score were evaluated. During the follow‐up, 70.8% of patients with ITMS converted to SPMS. None of the patients without ITMS did. At the end of the study, 63.6% of patients with ITMS had reached EDSS 6, whereas none of the patients lacking ITMS reached values above EDSS 3. When patients with benign MS were analyzed, 82% lacked ITMS. All patients with a nonbenign MS had ITMS. At the end of the study, the mean EDSS score was 4.64 in patients with ITMS and 1.31 in those without. The presence of oligoclonal IgM bands in cerebrospinal fluid is an unfavorable prognostic marker in MS. Ann Neurol 2003;53:000–000

Human small-intestinal epithelium contains functional natural killer lymphocytes

BACKGROUND & AIMS CD3(-) non-T lymphocytes constitute the second most abundant lymphoid subset in the human small-bowel epithelium, and these CD3(-) intraepithelial lymphocytes are virtually absent in active celiac disease. Phenotypically, they resemble natural killer cells and have been termed natural killer-like intraepithelial lymphocytes. Because of the limited availability of appropriate human samples, functional studies have not yet been reported, and it is not yet clear whether these are true natural killer cells. METHODS We used magnetic bead-based purification and flow cytometry to study several aspects of normal human small-bowel natural killer-like intraepithelial lymphocytes: intracellular cytokine content (basally and after activation); ability to lyse natural killer-sensitive K562 target cells; and expression of perforins, Fas ligand, and other functional markers. RESULTS CD3(-) intraepithelial lymphocytes cultured in interleukin-2 showed a higher lymphokine-activated killer activity than CD3(+) intraepithelial lymphocytes (48%-83% lysis exerted by CD3(-) intraepithelial lymphocytes at an effector-target cell ratio of 2:1 vs. 8%-18% by CD3(+) intraepithelial lymphocytes). Perforin content correlated with this lytic potential (75% +/- 4% in CD3(-) vs. 5% +/- 4% in CD3(+) intraepithelial lymphocytes). Both CD3(-) and CD3(+) cells displayed a type I cytokine profile (interferon-gamma > tumor necrosis factor-alpha > interleukin-2; undetectable interleukin-4 and interleukin-10). In addition to their activated phenotype, subsets of natural killer-like intraepithelial lymphocytes expressed CD8alphaalpha and intracellular CD3epsilon chain, showing the existence of heterogeneity within this cell lineage. CONCLUSIONS This is the first demonstration of functional natural killer cells within the human gut epithelium. These cells might play an important role in innate mucosal immunity (host defense and tumor surveillance) and tolerance.

Intrathecal IgM synthesis predicts the onset of new relapses and a worse disease course in MS.

BackgroundThe authors have recently described that intrathecal IgM synthesis (ITMS) correlates with a higher disability in patients with clinically definite MS (CDMS). ObjectiveTo follow-up a group of patients with MS in the initial stages of the disease to evaluate if the presence of ITMS correlates with a worse evolution. Methods Oligoclonal IgM bands were performed in 22 patients with MS with a mean of 1.14 months of evolution. Patients were followed for a period ranging from 6 to 36 months (mean, 21.4 months). During follow-up, time to conversion to CDMS, number of relapses, and changes in Expanded Disability Status Scale (EDSS) score were evaluated. ResultsPatients were divided into two groups according to the presence (Group 1, 10 patients) or absence (Group 2, 12 patients) of ITMS. No clinical differences were observed between the groups at inclusion in the study. During the follow-up, the probability of conversion to CDMS was greater in Group 1 (90% of the patients had converted to CDMS after 8 months of follow-up) than in Group 2 (51% of patients had converted to CDMS after 36 months of follow-up) (p = 0.0001). Patients from Group 1 had more relapses (mean, 2.0) than those from Group 2 (mean, 0.58) (p = 0.02). At the end of the study, patients from Group 1 had higher EDSS scores (mean, 1.70) than those from Group 2 (mean, 0.79) (p = 0.02). ConclusionThe presence of oligoclonal IgM bands in CSF can be a prognostic marker in the early phases of MS.

Intrathecal IgM synthesis in neurologic diseases: Relationship with disability in MS

Abstract—The authors studied the intrathecal IgM synthesis (ITMS) in paired sera and CSF samples from 65 patients with MS, 28 with CNS infection, 40 with other neurologic diseases and eight control subjects. ITMS was found in 30 patients with MS and in 20 with CNS infection, but not in patients with other neurologic diseases or in control subjects. In infectious samples, the ITMS is likely a primary response. In MS group, it was associated with higher Expanded Disability Status Scale index (p = 0.017).

Influence of oligoclonal IgM specificity in multiple sclerosis disease course

Oligoclonal IgM bands (OCMB) against myelin lipids predict an aggressive multiple sclerosis (MS) course. However, the clinical significance of OCMB without lipid specificity, present in other MS patients, remains unknown. We describe here a characterization of these antibodies and study their role in MS progression. Fifty-four MS patients showing CSF-restricted OCMB were included in this study at disease onset and followed-up during 61.1 ± 2.7 months. The specificity of OCMB and the CSF B-cell profile were investigated. A second CSF IgM study was performed in a group of eight patients. Thirty-eight patients showed OCMB against myelin lipids (M+L+) and other sixteen had OCMB lacking this specificity (M+L-). The CD5+ B cell subpopulation, responsible for most persistent IgM responses, was considerably higher in M+L+ than in M+L- patients (3.3 ± 0.6% versus 0.8 ± 0.2, P = 0.009). In addition, M+L+ bands persisted during disease course, while M+L- disappeared during follow-up. M+L+ patients suffered more relapses (4.2 ± 0.6 versus 1.6 ± 0.3, P = 0.002) and reached higher disability (EDSS score of 2.2 ± 0.2 versus 1.2 ± 0.2, P = 0.02) than M+L- group. These data corroborate that anti-lipid OCMB associate with an aggressive MS course and show that OCMB that do not recognize myelin lipids represent a transient immune response related to a more benign disease course. Multiple Sclerosis 2008; 14: 183—187. http://msj.sagepub.com

Immunological Markers of Optimal Response to Natalizumab in Multiple Sclerosis

OBJECTIVE To explore cell subsets and molecules that changed specifically in patients with multiple sclerosis (MS) who had an optimal response to natalizumab. Natalizumab is a monoclonal antibody that inhibits the migration of activated immune cells to the central nervous system. It shows high efficacy in modifying the natural history of MS and induces freedom of disease activity in about 40% of treated patients with MS. DESIGN Prospective study of intrathecal immunoglobulin synthesis and cerebrospinal fluid lymphocyte subsets in patients with MS before and 1 year after beginning treatment with natalizumab. We monitored clinical and magnetic resonance imaging activity during a median time of 2 years. SETTING Two tertiary hospitals from the Spanish National Health Service. PATIENTS A total of 23 patients with MS. MAIN OUTCOME MEASURES The differences between patients free of disease activity and patients with active disease during treatment. RESULTS Of the 23 patients, 10 (43.5%) remained free of disease activity during follow-up. The remaining 13 patients (56.5%) had relapses or new lesions despite natalizumab therapy. We did not find differences in demographic variables or clinical data between both groups prior to natalizumab therapy. All patients showed a decrease in cerebrospinal fluid CD4(+) cells regardless of their response to treatment. Conversely, only patients free of disease activity showed a decrease in local IgM and, to a lesser extent, in IgG synthesis. They also showed lower percentages of B cells, particularly of CD5(+) and plasmablast subsets that virtually disappeared after treatment with natalizumab. CONCLUSION These data indicate that inhibition of intrathecal antibody synthesis is associated with a complete therapeutic response to natalizumab in patients with aggressive MS.

Immunological mechanisms that associate with oligoclonal IgM band synthesis in multiple sclerosis

We described previously that multiple sclerosis (MS) patients with oligoclonal IgM against myelin lipids (M+) develop an aggressive disease. Our aim was to assess possible mechanisms regulating the production of these antibodies. We studied B cell subsets in 180 patients with MS, and 69 with other neurological diseases. M+ MS patients showed a moderate increase of CD5(+) B-cell percentage in peripheral blood and a considerable augment of these cells in cerebrospinal fluid (CSF) that correlated with intrathecal IgM production. The appearance of CD5(+) B cells into the central nervous system (CNS) was related to increased CXCL13 and TNF-alpha levels in CSF. Moreover, the presence of oligoclonal IgM associated with a SNP at position -376 of the TNF-alpha promoter. These results help to elucidate the B lymphocytes responsible for intrathecal IgM secretion in MS and the origin of this abnormal B-cell response in patients with aggressive MS.

Increased peripheral blood CD5+ B cells predict earlier conversion to MS in high-risk clinically isolated syndromes

Clinically isolated syndrome patients (CIS) with oligoclonal IgG bands (OCGB) are at high risk for clinically definite multiple sclerosis (MS). However, the outcome for individual patients is unpredictable and the search for reliable blood markers predicting early conversion to multiple sclerosis (MS) has clinical relevance. CD5+ B cells (CD5+Bc) are involved in some autoimmune diseases. This study investigated whether high blood CD5+Bc percentage can predict CIS conversion to MS. Fifty-five consecutive CIS showing OCGB were prospectively studied. Every patient underwent a brain MRI study and a flow cytometry analysis of CD5+Bc percentage. Conversion to MS was studied during follow-up. The CD5+Bc percentage was assessed in 40 controls and a cut-off value of 3.5% (mean + 2 SD) was calculated. A blood CD5+Bc percentage above this value predicted earlier conversion to MS in the whole group (hazard ratio [HR]: 3.40; 95% confidence interval [CI]: 1.69–6.68; p = 0.0005) and in CIS patients fulfilling three or more Barkhof–Tintoré criteria plus OCGB, who showed higher risk for MS (HR: 3.79; 95% CI: 1.86–15.32; p = 0.0018). Multivariate analysis also showed a predictive value for high blood CD5+Bc count (HR: 4.3; 95% CI: 1.9–9.5; p < 0.0001). It was concluded that high percentages of CD5+Bc independently associate with increased risk of early conversion to MS in CIS patients with OCGB and Barkhof–Tintoré criteria.

Natural killer cell subsets in cerebrospinal fluid of patients with multiple sclerosis

Changes in blood natural killer (NK) cells, important players of the immune innate system, have been described in multiple sclerosis (MS). We studied percentages and total cell counts of different effector and regulatory NK cells in cerebrospinal fluid (CSF) of MS patients and other neurological diseases to gain clearer knowledge of the role of these cells in neuroinflammation. NK cell subsets were assessed by flow cytometry in CSF of 85 consecutive MS patients (33 with active disease and 52 with stable MS), 16 with other inflammatory diseases of the central nervous system (IND) and 17 with non‐inflammatory neurological diseases (NIND). MS patients showed a decrease in percentages of different CSF NK subpopulations compared to the NIND group. However, absolute cell counts showed a significant increase of all NK subsets in MS and IND patients, revealing that the decrease in percentages does not reflect a real reduction of these immune cells. Remarkably, MS patients showed a significant increase of regulatory/effector (CD56bright/CD56dim) NK ratio compared to IND and NIND groups. In addition, MS activity associated with an expansion of NK T cells. These data show that NK cell subsets do not increase uniformly in all inflammatory neurological disease and suggest strongly that regulatory CD56bright and NK T cells may arise in CSF of MS patients as an attempt to counteract the CNS immune activation characteristic of the disease.