Myelin basic protein and S-100 antigen in cerebrospinal fluid of patients with multiple sclerosis in the acute phase

S100B Impairs Oligodendrogenesis and Myelin Repair Following Demyelination Through RAGE Engagement

Increased expression of S100B and its specific receptor for advanced glycation end products (RAGE) has been described in patients with multiple sclerosis (MS), being associated with an active demyelinating process. We previously showed that a direct neutralization of S100B reduces lysophosphatidylcholine (LPC)-induced demyelination and inflammation using an ex vivo demyelinating model. However, whether S100B actions occur through RAGE and how oligodendrogenesis and remyelination are affected are not clarified. To evaluate the role of the S100B–RAGE axis in the course of a demyelinating insult, organotypic cerebellar slice cultures (OCSC) were demyelinated with LPC in the presence or absence of RAGE antagonist FPS-ZM1. Then, we explored the effects of the S100B–RAGE axis inhibition on glia reactivity and inflammation, myelination and neuronal integrity, and on oligodendrogenesis and remyelination. In the present study, we confirmed that LPC-induced demyelination increased S100B and RAGE expression, while RAGE antagonist FPS-ZM1 markedly reduced their content and altered RAGE cellular localization. Furthermore, FPS-ZM1 prevented LPC-induced microgliosis and astrogliosis, as well as NF-κB activation and pro-inflammatory cytokine gene expression. In addition, RAGE antagonist reduced LPC-induced demyelination having a beneficial effect on axonal and synaptic protein preservation. We have also observed that RAGE engagement is needed for LPC-induced oligodendrocyte (OL) maturation arrest and loss of mature myelinating OL, with these phenomena being prevented by FPS-ZM1. Our data suggest that increased levels of mature OL in the presence of FPS-ZM1 are related to increased expression of microRNAs (miRs) associated with OL differentiation and remyelination, such as miR-23a, miR-219a, and miR-338, which are defective upon LPC incubation. Finally, our electron microscopy data show that inhibition of the S100B–RAGE axis prevents axonal damage and myelin loss, in parallel with enhanced functional remyelination, as observed by the presence of thinner myelin sheaths when compared with Control. Overall, our data implicate the S100B–RAGE axis in the extent of myelin and neuronal damage, as well as in the inflammatory response that follows a demyelinating insult. Thus, prevention of RAGE engagement may represent a novel strategy for promoting not only inflammatory reduction but also neuronal and myelin preservation and/or remyelination, improving recovery in a demyelinating condition as MS.

Research and progress on biomarkers of neuromyelitis optica spectrum disorders

Neuromyelitis optica spectrum disorders (NMOSD) are a demyelinating disorder of the central nervous system based on the involvement of the optic nerve and/or spinal cord. The disease is characterized by high recurrence and disability. NMOSD is mainly diagnosed by AQP4-IgG and MOG-IgG. However, there are still some patients with negative or undetermined double-antibody, and AQP4-IgG and MOG-IgG cannot indicate the clinical disease activity. Therefore, it is urgent to explore interesting biomarkers in serum and cerebrospinal fluid to promote early clinical diagnosis and/or as a target for diagnosis and treatment. This article summarized the research progress in serum and cerebrospinal fluid biomarkers of astrocytes, neurons, myelin sheath, and other damage after the onset of NMOSD. Besides the value of microglial activation-related proteins in the diagnosis and treatment of NMOSD was prospected, so as to promote the research progress of NMOSD.

Central nervous system: a modified immune surveillance circuit?

Immune surveillance in the central nervous system (CNS) was considered impossible because: (i) the brain parenchyma is separated from the blood circulation by the blood-brain barrier (BBB); (ii) the brain lacks lymphatic drainage and (iii) the brain displays low major histocompatibility complex class II (MHCII) expression. In this context, the BBB prevents entry of immune molecules and effector cells to the CNS. The absence of lymphatic vessels avoids CNS antigens from reaching the lymph nodes for lymphocyte presentation and activation. Finally, the low MHCII expression hinders effective antigen presentation and re-activation of T cells for a competent immune response. All these factors limit the effectiveness of the afferent and efferent arms necessary to carry out immune surveillance. Nevertheless, recent evidence supports that CNS is monitored by the immune system through a modified surveillance circuit; this work reviews these findings.

A lack of association between elevated serum levels of S100B protein and autoimmunity in autistic children

BACKGROUND

S100B is a calcium-binding protein that is produced primarily by astrocytes. Increased serum S100B protein levels reflect neurological damage. Autoimmunity may have a role in the pathogenesis of autism in some patients. Autoantibodies may cross the blood-brain barrier and combine with brain tissue antigens, forming immune complexes and resulting in neurological damage. We are the first to investigate the relationship between serum levels of S100B protein, a marker of neuronal damage, and antiribosomal P protein antibodies in autistic children.

METHODS

Serum S100B protein and antiribosomal P antibodies were measured in 64 autistic children in comparison to 46 matched healthy children.

RESULTS

Autistic children had significantly higher serum S100B protein levels than healthy controls (P < 0.001). Children with severe autism had significantly higher serum S100B protein than patients with mild to moderate autism (P = 0.01). Increased serum levels of antiribosomal P antibodies were found in 40.6% of autistic children. There were no significant correlations between serum levels of S100B protein and antiribosomal P antibodies (P = 0.29).

CONCLUSIONS

S100B protein levels were elevated in autistic children and significantly correlated to autistic severity. This may indicate the presence of an underlying neuropathological condition in autistic patients. Antiribosomal P antibodies may not be a possible contributing factor to the elevated serum levels of S100B protein in some autistic children. However, further research is warranted to investigate the possible link between serum S100B protein levels and other autoantibodies, which are possible indicators of autoimmunity to central nervous system in autism.

The S100B protein in biological fluids: more than a lifelong biomarker of brain distress

S100B is a calcium-binding protein concentrated in glial cells, although it has also been detected in definite extra-neural cell types. Its biological role is still debated. When secreted, S100B is believed to have paracrine/autocrine trophic effects at physiological concentrations, but toxic effects at higher concentrations. Elevated S100B levels in biological fluids (CSF, blood, urine, saliva, amniotic fluid) are thus regarded as a biomarker of pathological conditions, including perinatal brain distress, acute brain injury, brain tumors, neuroinflammatory/neurodegenerative disorders, psychiatric disorders. In the majority of these conditions, high S100B levels offer an indicator of cell damage when standard diagnostic procedures are still silent. The key question remains as to whether S100B is merely leaked from injured cells or is released in concomitance with both physiological and pathological conditions, participating at high concentrations in the events leading to cell injury. In this respect, S100B levels in biological fluids have been shown to increase in physiological conditions characterized by stressful physical and mental activity, suggesting that it may be physiologically regulated and raised during conditions of stress, with a putatively active role. This possibility makes this protein a candidate not only for a biomarker but also for a potential therapeutic target.

Repeated intrathecal triamcinolone acetonide administration in progressive multiple sclerosis: a review

At the present time, anti-inflammatory, immunomodulatory, or immunosuppressive treatments of multiple sclerosis (MS) are mainly effective in the early phases of the disease but are of less advantage in progressive phases. Current therapeutic strategies of both primary and secondary progressive MS are rare. One alternative may be intrathecal application of triamcinolone acetonide (TCA). Number of papers deal with advantages and disadvantages of intrathecal administration in MS. Former trials lacked detailed selection of MS patients, with small sample sizes, low steroid dosages, and only a small number of intrathecal administration of short acting steroids. The present paper summarizes recent trials performed following a different treatment regime. They were conducted in patients with progressive MS suffering mainly from spinal symptoms and documented a significant improvement of EDSS and walking distance (WD). Intrathecal TCA administration is a proposal to take into account as one therapy option in patients with a progressive clinical course and predominantly spinal symptoms.

Role of intraspinal steroid application in patients with multiple sclerosis

Clinical trials on patients with progressive multiple sclerosis (MS) have shown no clear evidence of an effective symptomatic treatment with improving disability. Immunomodulatory compounds efficaciously reduce the relapse rate. Numerous earlier papers exist on the pros and cons and/or on the efficacy of intrathecal administration of differing dosages of various conventional released steroids. Furthermore, this treatment approach was nearly abondoned owing to a debate on side effects and a missing proven superiority over intravenous systemic high dosage steroid administration. However, recent open-label studies in progressive MS patients with predominant spinal symptomatology investigated the repeated intraspinal application of the sustained-release compound triamcinolone acetonide (TCA). A distinct improvement of walking distance and MS scores in the short term and stabilization of this beneficial effect after repeat TCA application every 6-12 weeks was found. Moreover, patients with a relapse with acute onset of painful sensations showed a marked pain improvement after repeated TCA application following prior unsuccessful treatment with intravenous steroids. The available data from open studies ask for the performance of a randomized clinical trial, comparing intravenous with intrathecal steroid administration, to confirm the higher efficacy of the more invasive therapy with repeated lumbar puncture.

Cerebrospinal fluid biomarkers in multiple sclerosis

In patients with multiple sclerosis (MS) intensive efforts are directed at identifying biomarkers in bodily fluids related to underlying disease mechanisms, disease activity and progression, and therapeutic response. Besides MR imaging parameters cerebrospinal fluid (CSF) biomarkers provide important and specific information since changes in the CSF composition may reflect disease mechanisms inherent to MS. The different cellular and protein-analytical methods of the CSF and the recommended standard of the diagnostic CSF profile in MS are described. A brief update on possible CSF biomarkers that might reflect key pathological processes of MS such as inflammation, demyelination, neuroaxonal loss, gliosis and regeneration is provided.

Cerebrospinal fluid biomarkers of neurodegeneration in chronic neurological diseases

Chronic neurological diseases (CND) like amyotrophic lateral sclerosis (ALS), dementia or multiple sclerosis (MS) share a chronic progressive course of disease that frequently leads to the common pathological pathway of neurodegeneration, including neuroaxonal damage, apoptosis and gliosis. There is an ongoing search for biomarkers that could support early diagnosis of CND and help to identify responders to interventions in therapeutic treatment trials. Cerebrospinal fluid (CSF) is a promising source of biomarkers in CND, since the CSF compartment is in close anatomical contact with the brain interstitial fluid, where biochemical changes related to CND are reflected. We review recent advances in CSF biomarkers research in CND and thereby focus on markers associated with neurodegeneration.

Cerebrospinal fluid brain specific proteins in relation to nitric oxide metabolites during relapse of multiple sclerosis

This study investigated the cerebrospinal fluid (CSF) levels of ferritin, S100B as biomarkers for glial activation and NfH(SM135)--a biomarker of axonal damage--in relation to nitric oxide (NO) metabolites: nitrate and nitrite (NOx) during acute multiple sclerosis (MS) relapse. Thirty-four relapsing-remitting MS (RR-MS) patients during acute relapse and 12 controls were enrolled. Patients were assessed on Expanded Disability Status Scale (EDSS) and underwent lumbar puncture within two weeks following relapse. Twenty patients were available for further follow-up and were assessed on EDSS 6-8 weeks since the relapse onset. The CSF NOx (P<0.0001), NfH(SM135) (P=0.01) and S100B (P=0.009) but not ferritin (P>0.05) were significantly raised in MS group. There was a significant correlation between CSF ferritin and S100B in RR-MS group (P=0.004). CSF NOx did not correlate with S100B and ferritin in study groups. RR-MS patients with detectable NfH(SM135) levels had higher NOx compared with subjects having undetectable NfH(SM135) (P=0.03). In the follow-up study, raised baseline levels of NOx (P=0.016) or NfH(SM135) (P=0.04) inversely correlated with the clinical recovery grade expressed as relative EDSS change between baseline and follow-up. In conclusion, NO metabolites were increased and because of their correlation with a biomarker of axonal degeneration (neurofilaments) and a measure for clinical disability (EDSS), relapse-related nitrosative stress is likely to be relevant to the development of sustained disability in an individual patient.

Astrocytic activation in relation to inflammatory markers during clinical exacerbation of relapsing-remitting multiple sclerosis

The study aimed to assay the cerebrospinal fluid (CSF) levels of protein S100B, a biomarker of astrocyte activation in relation to kynurenic acid (KYNA) and nitric oxide (NO) metabolites, nitrate/nitrite (NOx) concentrations in acute relapse multiple sclerosis (MS) patients. Twenty relapsing-remitting MS (RR-MS) patients and 10 controls were enrolled. RR-MS patients were assessed on the expanded disability status scale (EDSS) and underwent lumbar puncture. The CSF KYNA, NOx and S100B levels were significantly higher in RR-MS group compared to controls (p = 0.01, 0.001, 0.04, respectively). There was a significant correlation between CSF S100B and KYNA (p = 0.01) but not NOx (p > 0.05) in RR-MS. CSF KYNA, NOx or S100B concentrations did not correlate with disease characteristics of MS patients. Our study suggests the activation of the kynurenine pathway leading to the increase of neuroprotective KYNA in the CSF of MS patients during acute relapse what contrasts with chronic phases of the disease.

Repeat intrathecal triamcinolone acetonide application is beneficial in progressive MS patients

Available immunomodulatory and conventional steroid treatment regimens provide a limited symptomatic benefit for patients with progressive multiple sclerosis (MS). We performed an open trial on the short-term efficacy of repeated intrathecal application of the sustained release steroid triamcinolone acetonide (TCA) in 27 progressive MS patients. Six TCA administrations, performed every third day, reduced the Expanded Disability Status Scale (EDSS) score [initial: 5.4+/-1.3, 3-7.5 (mean+/-SD, range); end: 4.9+/-1.1; 2.5-6.5; P<0.001] and significantly increased the walking distance and speed in particular after the fourth TCA injection. Concomitantly serially determined cerebrospinal fluid (CSF) markers of cell injury, neuron-specific enolase, total tau-protein, S-100, and beta-amyloid did not significantly change within the interval of TCA treatment. No serious side effects appeared. We conclude that repeat intrathecal injection of 40 mg TCA provides a substantial benefit in progressive MS patients with predominant spinal symptoms and does not alter CSF markers of neuronal cell injury.

Serum S100B in primary progressive multiple sclerosis patients treated with interferon-beta-1a

S100B belongs to a family of calcium-binding proteins implicated in intracellular and extracellular regulatory activities. This study of serum S100B in primary progressive multiple sclerosis (PPMS) is based on data obtained from a randomized, controlled trial of Interferon beta-1a in subjects with PPMS. The key questions were whether S100B levels were associated with either disability or MRI findings in primary progressive MS and whether Interferon beta-1a has an effect on their S100B levels. Serial serum S100B levels were measured using an ELISA method. The results demonstrated that serum S100B is not related to either disease progression or MRI findings in subjects with primary progressive MS given Interferon beta-1a. Furthermore there is no correlation between S100B levels and the primary and secondary outcome measures.

S100B in brain damage and neurodegeneration

S100B is a calcium-binding peptide produced mainly by astrocytes that exert paracrine and autocrine effects on neurons and glia. Some knowledge has been acquired from in vitro and in vivo animal experiments to understand S100B's roles in cellular energy metabolism, cytoskeleton modification, cell proliferation, and differentiation. Also, insights have been gained regarding the interaction between S100B and the cerebral immune system, and the regulation of S100B activity through serotonergic transmission. Secreted glial S100B exerts trophic or toxic effects depending on its concentration. At nanomolar concentrations, S100B stimulates neurite outgrowth and enhances survival of neurons during development. In contrast, micromolar levels of extracellular S100B in vitro stimulate the expression of proinflammatory cytokines and induce apoptosis. In animal studies, changes in the cerebral concentration of S100B cause behavioral disturbances and cognitive deficits. In humans, increased S100B has been detected with various clinical conditions. Brain trauma and ischemia is associated with increased S100B concentrations, probably due to the destruction of astrocytes. In neurodegenerative, inflammatory and psychiatric diseases, increased S100B levels may be caused by secreted S100B or release from damaged astrocytes. This review summarizes published findings on S100B regarding human brain damage and neurodegeneration. Findings from in vitro and in vivo animal experiments relevant for human neurodegenerative diseases and brain damage are reviewed together with the results of studies on traumatic, ischemic, and inflammatory brain damage as well as neurodegenerative and psychiatric disorders. Methodological problems are discussed and perspectives for future research are outlined.

Are there indicators of remyelination in blood or CSF of multiple sclerosis patients?

Knowing the mechanisms and the times of remyelination is not only an intriguing scientific challenge but it has also important consequences on the therapeutic approach to multiple sclerosis (MS). The neural-cell adhesion molecule (N-CAM) shows tempting suggestions about its possible involvement in reparative mechanisms, and, finally, in remyelination. In fact, its levels progressively increase in the cerebrospinal fluid (CSF) of acute MS patients, paralleling the progressive clinical improvement after the attack. Some information is also given about the ciliary neurotrophic factor (CNTF), whose CSF levels were found to be increased in MS patients who were recovering from an acute exacerbation.

Cerebrospinal fluid markers in multiple sclerosis: an overview

Cerebrospinal fluid (CSF), with its protein markers, is a formidable material for investigating the relationships among the various cell types involved during the initial phase of plaque formation, or, successively, in the remyelination process. Its analysis may give definite help in better focusing on therapeutic objectives and therapeutic tools. Therefore, the possible use of CSF MBP, S-100, GFAP, N-CAM, NGF, and CNTF in pathogenetic studies and in clinical follow-up is critically reviewed. The need for correct interpretation of the data, for uniformity and reliability of the analytical methods, and for easy access to them is stressed. CSF examination and MRI should not be considered as alternative tools, or in competition, but should be used together, to take the maximum advantage of their individual possibilities.

Cerebrospinal fluid analysis differentiates between relapsing-remitting and secondary progressive multiple sclerosis

OBJECTIVES

To find whether CSF analysis may differentiate between relapsing-remitting and secondary progressive multiple sclerosis.

METHODS

In 17 patients with relapsing-remitting and 16 patients with secondary progressive multiple sclerosis, all without current or recent relapses, albumin CSF: peripheral blood ratio, mononuclear cell number, CD4+, CD8+, and B1+ subsets, CD4+:CD8+ ratio, IgG, IgG index, IgM, IgM index, complement components C3 and C4, and C3 and C4 indices, myelin basic protein, neuron specific enolase, S100, and lactate were determined. For each measure the statistical distance measure D2 was calculated. For computation of a discriminant score variables with a P value< or =0.15 were included (two sided univariate t test). These were albumin CSF: peripheral blood ratio, mononuclear cell number, IgM, IgM index, C3, C4, neuron specific enolase, S100, and lactate. Simultaneous distributions of the variables were compared between both groups (multivariate t test) and a discriminant score was computed (linear discriminant analysis).

RESULTS

The discriminant score allocated all 14 relapsing-remitting patients to the relapsing-remitting group (positive score) and 12 of 13 secondary progressive patients to the secondary progressive group (negative score). One secondary progressive patient was allocated to the relapsing-remitting group.

CONCLUSIONS

Patients with relapsing-remitting or secondary progressive multiple sclerosis differ in CSF profile and CSF analysis may help to differentiate between relapsing-remitting and secondary progressive multiple sclerosis.

A specific and sensitive ELISA for measuring S-100b in cerebrospinal fluid

A sensitive, simple and specific sandwich ELISA for S-100b is described. This method involves the binding of a monoclonal anti-S-100b antibody to the wall of a microtitre plate. This capture antibody is subsequently incubated with S-100b standard, control or patient sample in the form of cerebrospinal fluid (CSF). After incubation, the microtitre plate is washed and horseradish peroxidase-labelled polyclonal anti-S-100b is added (detector antibody). The amount of detector antibody bound to the microtitre plate is proportional to the amount of S-100b in the sample. The assay has a lower limit of detection of 0.04 ng/ml and shows < 0.006% reactivity with the closely related polypeptide S-100a. The assay has a mean within-batch precision of 9.3 and 5.6% at S-100b concentrations of 0.38 and 0.8 ng/ml, respectively. The between batch precision is 8.9 and 8.1% at S-100b concentrations of 0.12 and 0.34 ng/ml, respectively. The recovery of S-100b from CSF spiked with 0.5 ng/ml was 94% with a CV of 8.5%. The assay may be completed in less than 5 h using precoated microtitre plates, thus lending itself to routine use in clinical laboratories. Using this ELISA, 154 CSF samples were analysed and 19% of samples were found to have elevated levels. The highest levels were found in patients with cerebral haemorrhage or central nervous system malignancy. S-100b concentrations from individuals without evidence of neurological disease were found to be less than 0.4 ng/ml. Only 5% of patients with multiple sclerosis were found to have elevated CSF S-100b concentrations. Serial CSF samples taken from a patient with an infected in-dwelling shunt showed a dramatic decline, suggesting that S-100b is rapidly cleared.

Cerebrospinal neuron-specific enolase, S-100 and myelin basic protein in neurological disorders

In this study levels of neuron-specific enolase (NSE), S-100 protein (S-100) and myelin basic protein (MBP) in cerebrospinal fluid (CSF) of children and adults with distinct neurological disorders were examined. A previous study from our department demonstrated age related reference values for these brain-specific proteins in CSF. The median concentration level of the 3 proteins in 17 different neurological disease groups versus the reference group was compared. Significantly higher MBP values were observed in patients with multiple sclerosis (MS), cerebrovascular accident (CVA), metabolic disorder and infection. Furthermore, significantly higher values were demonstrated for S-100 in CVA and for NSE in metabolic diseases. In CVA, the NSE and S-100 values were significantly related with MBP values, whereas in MS the NSE and S-100 were not related with MBP values.

Cerebrospinal fluid markers in neurological disorders

Cerebrospinal fluid (CSF) markers are a useful tool for determining disease progression or activity in some neurological disorders which need parameters both for evaluating treatments and investigating pathobiological evolution in research-oriented follow-up. A number of CSF proteins are reviewed with data on biological properties, analytical methods, clinical usefulness of: myelin basic protein, S-100 protein, glial fibrillary acidic protein, neural-cell adhesion molecule, neuron-specific enolase and others.

Four year double-blind controlled study of levamisole in multiple sclerosis

41 patients with definite multiple sclerosis (MS) in the stationary phase entered this four year double-blind levamisole-placebo controlled study. 22 patients were treated with levamisole, 150 or 200 mg once a week for a 4 year period, and other 19 with placebo with the same schedule. Patients were put in one of the two groups at random. The treatment was then stopped for those patients who presented a clear exacerbation before the end of the 4 year trial period, and these cases have been considered as negative. Of the group treated with levamisole 8 patients presented an exacerbation during the observation period, and 14 did not. The group treated with placebo presented 14 subjects who had exacerbations and 5 patients who did not. The difference between the two groups was statistically significant. This study demonstrates that levamisole significantly reduced the number of MS patients with acute relapse during the 4 year period of treatment. Nevertheless, not all patients were free from relapse: that could probably suggest that different immunopathological backgrounds may underlie what we usually call MS.

Autoimmunity in demyelinating diseases

Demyelinative diseases of the CNS and peripheral nervous system can be distinguished on the basis of primary mediation by antibody or T lymphocytes (or failure of the T-cell-mediated response) and on the basis of chronicity. The principal mechanisms are autoimmunization to myelin antigens after actual immunization with tissue or infection with cross-reactive viruses or, alternatively, persistent infection of the nervous system (viral or spirochetal) with an associated immune response to the pathogen.