Cytokines in multiple sclerosis: methodological aspects and pathogenic implications

The level of cytokines in tears as a novel indicator of demyelinating diseases

INTRODUCTION

A novel research objective is to identify new molecules in more readily accessible biological fluids that could be used in the diagnosis of multiple sclerosis (MS) and other demyelinating disorders.

AIM

To compare the level of selected cytokines in tears between patients with MS or other demyelinating disorder and healthy controls.

MATERIAL AND METHODS

84 patients with diagnosed MS during remission or with other demyelinating disease of the CNS and 70 healthy controls were enrolled in the study. Tears were collected without any stimulation and stored till the day of assessment. The concentration of selected cytokines was measured by the Bio-Plex Pro Human cytokine screening panel 27 cytokines assay according to the manufacturer's instructions. Statistical analysis was performed with Statistica 13.

RESULTS

IL-1b level was significantly lower in the study group compared to the control group [3,6 vs 8.71, p < 0.001]. The same pattern was observed for IL-6 [3,1 vs 5.26, p = 0.027] and IL-10 [1,7 vs 10.92, p < 0.001] (Table 1). In the study group, IL-1RA (p = 0.015), IL-5 (p = 0.04), IL-9 (p = 0.014), and IL-15 (p = 0.037) showed significant correlations with age. In the total sample, IL-1Ra (p = 0.016) and IFN-g (p = 0.041) were significantly correlated with age, while in the control group, IL-8 (p = 0.09), MIP-1a (p = 0.009), and RANTES (p = 0.031) showed significant correlations.

CONCLUSIONS

Our results show that MS and other demyelination diseases lead to decrease in the overall level of cytokines in tears. Further research is needed to determine the role of tear fluid in the assessment of demyelinating disorders like MS.

IL-6 and TNF-α responses to acute and regular exercise in adult individuals with multiple sclerosis (MS): a systematic review and meta-analysis

Background

In both the general population and people with multiple sclerosis (PwMS), physical exercise is associated with improved mental well-being. Moreover, there is evidence of the possible protection of physical activity against disease progression in multiple sclerosis (MS). However, the question arises if acute or regular exercise has any impact on the immune system in PwMS. To answer this question, we performed a systematic review and meta-analysis on both plasma and serum cytokine levels (IL-6 and TNF-α) before and after acute and regular exercise among PwMS and compared to healthy controls.

Method

We performed an online search via PubMed, EMBASE, SCOPUS, Web of Science, and Cochrane Library till September 2021 to identify original studies on IL-6 and TNF-α changes after acute and regular exercise in PwMS and controls. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), 11 original studies were included in the meta-analysis. Sensitivity analyses were used to identify the origins of heterogeneity. R 4.0.4 was used to perform the meta-analysis of IL-6 and TNF-α levels before and after acute and regular exercise in PwMS, compared to controls. This study does not qualify for a clinical trial number.

Results

IL-6 levels did neither increase nor decrease after acute and regular exercise in PwMS, and compared to controls (pre- vs. post-intervention: Standardized Mean Difference (SMD) -0.09, 95% CI [−0.29; 0.11], p-value = 0.37, PwMS vs. Control: SMD −0.08, 95% CI [−0.33; 0.16], p-value = 0.47). In PwMS, TNF-α levels decreased after regular exercise and when TNF-α levels of both acute and regular exercise were pooled (pre- vs. post-intervention: SMD −0.51, 95% CI [-0.91; 0.11], p-value = 0.01, PwMS vs. Control: SMD −0.23, 95% CI [−0.66; 0.18], p-value = 0.26). TNF-α levels did neither increase nor decrease after acute and regular exercise in PwMS, when compared to controls.

Conclusion

This systematic review and meta-analysis show that exercise does not lead to significant changes in peripheral levels of IL-6 in PwMS in contrast to the observed response in healthy subjects and other medical contexts. However, regular exercise had a specific anti-inflammatory effect on blood TNF-α levels in PwMS. It remains to be investigated why PwMS display this different exercise-induced pattern of cytokines.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40001-022-00814-9.

Prevalence of sea, seb, sec, sed, and tsst-1 genes of Staphylococcus aureus in nasal carriage and their association with multiple sclerosis

Background

Microbial superantigens might initiate or exacerbate autoimmune responses against particular tissues, organs or systems. This study aimed to examine the prevalence of sea, seb, sec, sed, and tsst-1 genes of Staphylococcus aureus in nasal carriage and their association with multiple sclerosis (MS).

Methods

Nasal swabs were collected from 150 MS patients and 150 healthy individuals (control group) to isolate S. aureus and investigate their superantigen genes (sea, seb, sec, sed and tsst-1) using PCR.

Results

A total of 300 participants were enrolled in the study, matched for age and gender (150 patients in the MS group and 150 in the control group). The prevalence of S. aureus colonization in MS patients and control groups was 42% and 23.3%, respectively. There was a statistically significant association between S. aureus colonization and MS disease (p<0.001; odds ratio 2.4; 95% confidence interval 1.4-3.9). No significant association was observed between the presence of S. aureus harboring sea, seb, sec, sed and tsst-1 genes with MS disease.

Conclusion

The rate of S. aureus nasal carriage is higher in patients with MS. Our study's results suggest that further investigation into whether there is a connection between MS and nasal exposure to staphylococcal superantigens is warranted.

Impact of Exercise on Innate Immunity in Multiple Sclerosis Progression and Symptomatology

Multiple Sclerosis (MS), an idiopathic progressive immune-mediated neurological disorder of the central nervous system (CNS), is characterized by recurrent episodes of inflammatory demyelination and consequent axonal deterioration. It accounts for functional deterioration and lasting disability among young adults. A body of literature demonstrates that physical activity counteracts fatigue and depression and may improve overall quality of life in MS patients. Furthermore, much data indicates that exercise ameliorates chronic neuroinflammation and its related pathologies by tipping cytokine profiles toward an anti-inflammatory signature. Recent data has focused on the direct impact of exercise training on the innate immune system by targeting toll-like receptors (TLRs), signaling pattern recognition receptors that govern the innate immune response, shedding light on the physiological role of TLRs in health and disease. Indeed, TLRs continue to emerge as players in the neuroinflammatory processes underpinning MS. This review will highlight evidence that physical activity and exercise are potential immunomodulatory therapies, targeting innate signaling mechanism(s) to modulate MS symptom development and progression.

Resistant Strains of Enterotoxigenic Staphylococcus aureus; Unknown Risk for Multiple Sclerosis Exacerbation

Background:

Despite all advances in neurological sciences, there are unknown aspects in the epidemiology of multiple sclerosis (MS). Based on this hypothesis, the enterotoxigenic strains of Staphylococcus aureus (S. aureus) are possible risk factors for exacerbations of MS.

Objectives:

The present study was carried out to investigate the role of resistant strains of enterotoxigenic S. aureus in MS exacerbation.

Materials and Methods:

Two-hundred nasal swab samples were collected from non-MS (n = 80), MS stable (n = 60) and MS exacerbation (n = 60) groups. Samples were cultured and those that were S. aureus-positive were analyzed for the presence of enterotoxins, using polymerase chain reaction (PCR). Antimicrobial susceptibility was performed using disk diffusion method.

Results:

Ninety out of 200 nasal samples (45%) were positive for S. aureus. The highest levels of nasal colonization were seen in MS exacerbation group (68.33%). The most commonly detected enterotoxins were sea (30%), sec (15.55%) and seb (11.11%). There were significant differences between S. aureus colonization and type of samples (P = 0.026) and, also, between type of samples and prevalence of enterotoxins (P = 0.022). The highest levels of enterotoxigenic genes were seen in MS exacerbation group. The S. aureus strains had the highest levels of resistance against tetracycline (80%), ampicillin (72.22%), methicillin (66.66%), erythromycin (66.66%), oxacillin (63.33%), trimethoprim-sulfamethoxazole (61.11%) and cotrimoxazole (55.55%).

Conclusions:

Our findings should raise awareness about the role of sea and sec enterotoxins, in resistant strains of S. aureus, as a risk factor for MS exacerbation. It is better to keep MS patients away from polluted environments of hospitals and health centers.

Stimulated PBMC-produced IFN-γ and TNF-α are associated with altered relapse risk in multiple sclerosis: results from a prospective cohort study

BACKGROUND

Altered reactivity of peripheral blood mononuclear cells (PBMC) and their production of cytokines may affect multiple sclerosis (MS) clinical course. We assessed the relationship of stimulated PBMC-produced IFN-γ, TNF-α, IL-4 and IL-10 in modulating relapse risk using a prospective cohort with established relapsing-remitting MS.

METHODS

Cytokine production from PBMCs taken in summer and winter was measured by ELISA. Predictors of cytokines assessed by multilevel mixed-effects linear regression. Predictors of relapse assessed by survival analysis.

RESULTS

Increasing IFN-γ was associated with increasing relapse risk, while increasing TNF-α reduced relapse risk after adjusting for IFN-γ. IL-10 and IL4 were not consistently associated with relapse risk. IFN-γ's effects on relapse were greatly attenuated by immunomodulatory therapies, by summer season and by higher serum vitamin D, whereas TNF-α's inverse association with relapse was only present in these circumstances. The TNF-α inverse association with relapse was only present among persons carrying the wild-type of the functional SNP rs1800693 in TNFRSF1A that has been previously associated with MS risk.

CONCLUSIONS

We found strong effects of IFN-γ and TNF-α on relapse risk, these differing by immunomodulatory therapy, season, and serum vitamin D, as well as by genotype. These results indicate altered reactivity of immune cells modulate MS disease.

Simultaneous presentation of acute disseminated encephalomyelitis (ADEM) and systemic lupus erythematosus (SLE) after enteroviral infection: can ADEM present as the first manifestation of SLE?

Central Nervous System (CNS) involvement of Systemic Lupus Erythematosus (SLE) includes a broad range of neuropsychiatric syndromes. Acute Disseminated Encephalomyelitis (ADEM) is a demyelinating CNS disorder characterized by encephalopathy and multifocal lesions predominantly involving the white matter on brain magnetic resonance imaging. ADEM associated with SLE has been only rarely reported. We report an unusual case of a 17-year-old girl who developed ADEM after enteroviral infection as the first manifestation of SLE. The authors emphasize that the patient's illness was preceded by enteroviral infection and that ADEM occurred before any other symptoms of SLE, which makes this case unique.

Effects of interferon β-1a and interferon β-1b monotherapies on selected serum cytokines and nitrite levels in patients with relapsing-remitting multiple sclerosis: a 3-year longitudinal study

OBJECTIVE

Interferon (IFN)β treatment is a mainstay of relapsing-remitting multiple sclerosis (RRMS) immunotherapy. Its efficacy is supposedly a consequence of impaired trafficking of inflammatory cells into the central nervous system and modification of the proinflammatory/antiinflammatory cytokine balance. However, the effects of long-term monotherapy using various IFNβ preparations on cytokine profiles and the relevance of these effects for the therapy outcome have not yet been elucidated.

METHODS

Changes were compared in serum levels of TNFα, IFNγ, interleukin (IL)-6, IL-10 and nitrite between RRMS patients given 3-year treatment with intramuscular IFNβ-1a (30 μg once a week) or subcutaneous IFNβ-1b (250 μg every other day). Only the data from patients who completed the 3-year study (n = 20 and n = 18, respectively) were analyzed.

RESULTS

Three-year IFNβ-1a or IFNβ-1b monotherapy reduced serum nitrite levels by 77 and 71%, respectively, lowered multiple sclerosis relapse annual rate by 70 and 71%, respectively, and significantly and similarly lowered Expanded Disability Status Scale scores in both study groups (by 0.9 on average). The two monotherapies showed little if any effect on cytokine levels and cytokine level ratios after the first year, but exerted diverging effects on these indices later on; the only exception was the IFNγ/IL-6 ratio that showed a monotonous rise in both study groups over the entire study period.

CONCLUSION

During long-term IFNβ monotherapy, the levels of the studied cytokines show no relevance to the course of RRMS and neurological status of patients, whereas there seems to be a link between these clinical indices and the activity of nitric oxide-mediated pathways.

Pain in experimental autoimmune encephalitis: a comparative study between different mouse models

BACKGROUND

Pain can be one of the most severe symptoms associated with multiple sclerosis (MS) and develops with varying levels and time courses. MS-related pain is difficult to treat, since very little is known about the mechanisms underlying its development. Animal models of experimental autoimmune encephalomyelitis (EAE) mimic many aspects of MS and are well-suited to study underlying pathophysiological mechanisms. Yet, to date very little is known about the sensory abnormalities in different EAE models. We therefore aimed to thoroughly characterize pain behavior of the hindpaw in SJL and C57BL/6 mice immunized with PLP139-151 peptide or MOG35-55 peptide respectively. Moreover, we studied the activity of pain-related molecules and plasticity-related genes in the spinal cord and investigated functional changes in the peripheral nerves using electrophysiology.

METHODS

We analyzed thermal and mechanical sensitivity of the hindpaw in both EAE models during the whole disease course. Qualitative and quantitative immunohistochemical analysis of pain-related molecules and plasticity-related genes was performed on spinal cord sections at different timepoints during the disease course. Moreover, we investigated functional changes in the peripheral nerves using electrophysiology.

RESULTS

Mice in both EAE models developed thermal hyperalgesia during the chronic phase of the disease. However, whereas SJL mice developed marked mechanical allodynia over the chronic phase of the disease, C57BL/6 mice developed only minor mechanical allodynia over the onset and peak phase of the disease. Interestingly, the magnitude of glial changes in the spinal cord was stronger in SJL mice than in C57BL/6 mice and their time course matched the temporal profile of mechanical hypersensitivity.

CONCLUSIONS

Diverse EAE models bearing genetic, clinical and histopathological heterogeneity, show different profiles of sensory and pathological changes and thereby enable studying the mechanistic basis and the diversity of changes in pain perception that are associated with distinct types of MS.

Exercise and disease progression in multiple sclerosis: can exercise slow down the progression of multiple sclerosis?

It has been suggested that exercise (or physical activity) might have the potential to have an impact on multiple sclerosis (MS) pathology and thereby slow down the disease process in MS patients. The objective of this literature review was to identify the literature linking physical exercise (or activity) and MS disease progression. A systematic literature search was conducted in the following databases: PubMed, SweMed+, Embase, Cochrane Library, PEDro, SPORTDiscus and ISI Web of Science. Different methodological approaches to the problem have been applied including (1) longitudinal exercise studies evaluating the effects on clinical outcome measures, (2) cross-sectional studies evaluating the relationship between fitness status and MRI findings, (3) cross-sectional and longitudinal studies evaluating the relationship between exercise/physical activity and disability/relapse rate and, finally, (4) longitudinal exercise studies applying the experimental autoimmune encephalomyelitis (EAE) animal model of MS. Data from intervention studies evaluating disease progression by clinical measures (1) do not support a disease-modifying effect of exercise; however, MRI data (2), patient-reported data (3) and data from the EAE model (4) indicate a possible disease-modifying effect of exercise, but the strength of the evidence limits definite conclusions. It was concluded that some evidence supports the possibility of a disease-modifying potential of exercise (or physical activity) in MS patients, but future studies using better methodologies are needed to confirm this.

Exercise in multiple sclerosis -- an integral component of disease management

Multiple sclerosis (MS) is the most common chronic inflammatory disorder of the central nervous system (CNS) in young adults. The disease causes a wide range of symptoms depending on the localization and characteristics of the CNS pathology. In addition to drug-based immunomodulatory treatment, both drug-based and non-drug approaches are established as complementary strategies to alleviate existing symptoms and to prevent secondary diseases. In particular, physical therapy like exercise and physiotherapy can be customized to the individual patient's needs and has the potential to improve the individual outcome. However, high quality systematic data on physical therapy in MS are rare. This article summarizes the current knowledge on the influence of physical activity and exercise on disease-related symptoms and physical restrictions in MS patients. Other treatment strategies such as drug treatments or cognitive training were deliberately excluded for the purposes of this article.

Staphylococcus aureus harbouring Enterotoxin A as a possible risk factor for multiple sclerosis exacerbations

BACKGROUND

Staphylococcus aureus may produce superantigens that can non-specifically activate CD4(+) cells to potentially target the myelin basic protein.

OBJECTIVE

This study examined the association between individuals with multiple sclerosis (MS) and colonization with S. aureus harbouring superantigens.

METHODS

Nasal swabs were collected from non-MS subjects and patients with MS who had not experienced a relapse in the past six months (MS stable group) and who had suffered a relapse within 30 days of study recruitment (MS exacerbation group). S. aureus was isolated from the anterior nares of participants following standard procedures and staphylococcal superantigen genes (sea, seb, and tsst-1) were detected using standard laboratory PCR techniques.

RESULTS

The study enrolled 204 patients, 80 in the non-MS and MS stable groups and 44 patients in the MS exacerbation group. Overall, 27.0% of patients were colonized with S. aureus with no significant differences identified between study groups. Amongst individuals colonized with S. aureus, the prevalence of sea was significantly greater in the MS exacerbation versus non-MS study group (p < 0.05; odds ratio 7.9; 95% confidence interval 1.2-49.5).

CONCLUSIONS

The ability to rapidly screen patients for the presence of S. aureus producing sea may serve as a useful marker of a potential MS exacerbation.

Animal models of multiple sclerosis--potentials and limitations

Experimental autoimmune encephalomyelitis (EAE) is still the most widely accepted animal model of multiple sclerosis (MS). Different types of EAE have been developed in order to investigate pathogenetic, clinical and therapeutic aspects of the heterogenic human disease. Generally, investigations in EAE are more suitable for the analysis of immunogenetic elements (major histocompatibility complex restriction and candidate risk genes) and for the study of histopathological features (inflammation, demyelination and degeneration) of the disease than for screening of new treatments. Recent studies in new EAE models, especially in transgenic ones, have in connection with new analytical techniques such as microarray assays provided a deeper insight into the pathogenic cellular and molecular mechanisms of EAE and potentially of MS. For example, it was possible to better delineate the role of soluble pro-inflammatory (tumor necrosis factor-α, interferon-γ and interleukins 1, 12 and 23), anti-inflammatory (transforming growth factor-β and interleukins 4, 10, 27 and 35) and neurotrophic factors (ciliary neurotrophic factor and brain-derived neurotrophic factor). Also, the regulatory and effector functions of distinct immune cell subpopulations such as CD4+ Th1, Th2, Th3 and Th17 cells, CD4+FoxP3+ Treg cells, CD8+ Tc1 and Tc2, B cells and γδ+ T cells have been disclosed in more detail. The new insights may help to identify novel targets for the treatment of MS. However, translation of the experimental results into the clinical practice requires prudence and great caution.

Multiple sclerosis: etiology and treatment strategies

OBJECTIVE

To review the etiology and treatment strategies for multiple sclerosis (MS).

DATA SOURCES

Published information on MS and targeted treatment strategies extending back to 1955. The search terms multiple sclerosis and pathology, prevalence, genetics, and each of the common symptoms of MS were used.

STUDY SELECTION

Seventy-two studies were reviewed based on level 1, 2, and 3 search strategies.

DATA EXTRACTION

Level 1 search strategy targeted evidence-based trials of large sample size (N > 100) with a randomized, double-blind, placebo-controlled design. A level 2 search targeted additional trials with some of the traits of evidence-based trials. A level 3 search compared key findings in reports of very small (N < 15) poorly designed trials with the results of well-designed trials.

DATA SYNTHESIS

MS affects each patient differently, making a definitive diagnosis and management of symptoms very difficult. Effective symptom management requires an interprofessional team approach.

CONCLUSION

Despite all the research dedicated to this disease, there is still no cure. The treatments currently available function at best only to slow the disease progression and mitigate symptoms. Using the skills and knowledge available from a team of health care professionals will help patients navigate the trials and tribulations that follow throughout a life with MS.

Anti-inflammatory cytokine gene therapy decreases sensory and motor dysfunction in experimental Multiple Sclerosis: MOG-EAE behavioral and anatomical symptom treatment with cytokine gene therapy

Multiple Sclerosis (MS) is an autoimmune inflammatory disease that presents clinically with a range of symptoms including motor, sensory, and cognitive dysfunction as well as demyelination and lesion formation in brain and spinal cord. A variety of animal models of MS have been developed that share many of the pathological hallmarks of MS including motor deficits (ascending paralysis), demyelination and axonal damage of central nervous system (CNS) tissue. In recent years, neuropathic pain has been recognized as a prevalent symptom of MS in a majority of patients. To date, there have been very few investigations into sensory disturbances in animal models of MS. The current work contains the first assessment of hind paw mechanical allodynia (von Frey test) over the course of a relapsing-remitting myelin oligodendrocyte glycoprotein induced experimental autoimmune encephalomyelitis (MOG-EAE) rat model of MS and establishes the utility of this model in examining autoimmune induced sensory dysfunction. We demonstrate periods of both decreased responsiveness to touch that precedes the onset of hind limb paralysis, and increased responsiveness (allodynia) that occurs during the period of motor deficit amelioration traditionally referred to as symptom remission. Furthermore, we tested the ability of our recently characterized anti-inflammatory IL-10 gene therapy to treat the autoimmune inflammation induced behavioral symptoms and tissue histopathological changes. This therapy is shown here to reverse inflammation induced paralysis, to reduce disease associated reduction in sensitivity to touch, to prevent the onset of allodynia, to reverse disease associated loss of body weight, and to suppress CNS glial activation associated with disease progression in this model.

Cytokine responses to acute and chronic exercise in multiple sclerosis

Regular exercise reduces functional loss associated with multiple sclerosis (MS). However, the impact of exercise on inflammatory mediators associated with disease activity remains relatively unexplored. The purpose of this study was to determine whether ambulatory MS subjects would respond similarly to aerobic cycle training compared with matched controls on circulating immune variables, interleukin (IL)-6, tumor necrosis factor (TNF)-α and interferon (IFN)-γ. Eleven MS and 11 non-MS control subjects (8 women and 3 men in both groups) matched in age, height, body mass, body fat, and peak O2 uptake completed the study. Subjects completed 30 min of cycle ergometry at 60% of peak O2 uptake, 3 day/wk for 8 wk. Plasma cytokine concentrations were determined before and after exercise at weeks 0, 4, and 8. MS and control subjects showed a similar cytokine responses to exercise. IL-6 at rest tended to decrease ( P = 0.08) with training in both groups. Resting plasma TNF-α tended to be higher in MS compared with controls throughout the study ( P = 0.08). MS subjects showed elevated resting TNF-α in MS at the end of the 8-wk program ( P = 0.04), whereas resting TNF-α remained unchanged in controls ( P > 0.05). Resting plasma IFN-γ at rest was elevated in MS subjects ( P = 0.008) and unchanged in controls at the end of the intervention ( P > 0.05). The response of plasma IL-6, TNF-α, and IFN-γ after a single bout of exercise was similar between MS and control subjects ( P > 0.05). Additional research to understand the impact of exercise on immune variables in MS is warranted.

Exercise and brain health--implications for multiple sclerosis: Part II--immune factors and stress hormones

Part I of this review addressed the possible modulatory role of exercise on neuronal growth factors to promote brain health in neurodegenerative diseases such as multiple sclerosis (MS), which is characterized by varied patterns of inflammation, demyelination and axonal loss. Part II presents evidence that supports the potential neuroprotective effect of exercise on the modulation of immune factors and stress hormones in MS. Many current therapies used to attenuate MS progression are mediated, at least in part, through alterations in the relative concentrations of pro- and anti-inflammatory cytokines. Exercise-induced alterations in local and systemic cytokine production may also benefit immune function in health and disease. Exercise immunomodulation appears to be mediated by a complex interaction of hormones, cytokines and neural factors that may favorably influence immune variables in MS. The promising interplay between exercise and brain health in MS deserves further investigation.

Differential regulation of cytokine production by PI3Kdelta in human monocytes upon acute and chronic inflammatory conditions

Deregulated production of cytokines, including IL-1beta, IL-6 and TNF plays an important role in chronic inflammation. Relevant to this condition, direct cellular contact with stimulated T cells is a potent inducer of cytokine production in human monocytes/macrophages. We previously demonstrated that PI3Ks regulate differential production of IL-1beta and its specific inhibitor secreted IL-1 receptor antagonist (sIL-1Ra) by human monocytes. Here we show that in contrast with PI3Kalpha, beta and gamma, PI3Kdelta accounts for most of the PI3K-dependent signaling ruling the production of IL-1beta, IL-6, TNF and sIL-1Ra in monocytes activated by cellular contact with stimulated T cells (mimicked by CHAPS-solubilized membranes of stimulated T cells, CE sHUT) and lipopolysaccharides (LPS); the latter stimuli being relevant to chronic/sterile and acute/infectious inflammation, respectively. Interestingly, PI3Kdelta activity dampened the production of pro-inflammatory cytokines in LPS-activated monocytes, but induced it in CE sHUT-activated cells. In both CE sHUT- and LPS-activated monocytes PI3Kdelta regulated cytokine transcript expression through the phosphorylation/inactivation of glycogen synthase kinase-3beta (GSK3beta). The blockade of GSK3beta displayed inverse effects to those of PI3Kdelta blockade. Thus, by displaying opposite functions in conditions mimicking chronic/sterile and acute/infectious inflammation, i.e., by repressing pro-inflammatory cytokine expression in LPS-activated monocytes but inducing such mediators in T cell contact-activated monocytes, PI3Kdelta represents a potential therapeutic target specific to chronic/sterile inflammatory conditions.

Synergistic immune responses induced by endogenous retrovirus and herpesvirus antigens result in increased production of inflammatory cytokines in multiple sclerosis patients

Human endogenous retroviruses (HERV) and herpesviruses are increasingly associated with the pathogenesis of the neurological inflammatory disease multiple sclerosis (MS). Herpesviruses are capable of HERV activation and simultaneous presence of HERV and herpesvirus antigens have a synergistic effect on cell-mediated immune responses, which tend to be higher in MS patients in comparison with healthy individuals. Here, we investigate whether these synergistic immune responses are reflected in changes in the production of proinflammatory cytokines. Using enzyme-linked immunosorbent assays (ELISAs), we have performed a comparative study between MS patients and healthy controls to investigate the production of interferon (IFN)-gamma, interleukin (IL) 2, or IL-10 as well as the balance between Th1 and Th2 responses in supernatants from peripheral blood mononuclear cells (PBMC) stimulated with HERV and herpes antigen combinations. We have found a significant disproportion in Th1/Th2 responses in PBMCs from MS patients caused by the joint presence of HERV and herpes antigens. The results also showed a significantly higher IFN-gamma production in cells from MS patients; additionally, this production correlated with the synergistic cell proliferations whereas we did not find such a correlation in healthy controls. Our findings suggest that the increased production of IFN-gamma and the induced imbalance in Th1/Th2 responses favouring the inflammatory reactions in MS patients may lead to progression of the disease.

Vasculitis and rheumatologic diseases may play role in the pathogenesis of acute disseminated encephalomyelitis (ADEM)

Acute disseminated encephalomyelitis (ADEM) is defined as a multifocal, monophasic, demyelinating, and inflammatory disease involving the central nervous system. It typically begins within 6 weeks of an antigenic challenge such as infection or immunization. Perivenous inflammation, edema and demyelination are the pathological hallmarks of ADEM. Reactivity of T-cells against myelin components such as myelin basic protein has been found in children with ADEM. The triggers for immune responses in ADEM are not known, but the two most widely accepted hypotheses are molecular mimicry and self-sensitization secondary to CNS infection. Inflammatory cytokines including tumor necrosis factor alpha (TNFalpha), interleukin 2 (IL2) and interferon gamma (INFgamma) are thought to be important in lesion formation in ADEM. Due to the active role of inflammatory cytokines in the pathogenesis of ADEM, any disease contributing to systemic formation of inflammatory cytokines can potentially be an etiologic factor for the initiation of ADEM. In vasculitis and rheumatologic diseases the number of T-cells, T helper type 1 cytokines and other inflammatory cytokines such as TNFalpha increase substantially. We present this hypothesis that in such setting of inflammation, adhesion molecules are up-regulated on the brain capillary endothelium by cytokines and other inflammatory mediators, altering the permeability of the brain blood barrier and so allowing for inflammatory cell migration. The migratory cells attack the basic myelin protein and the final result is the demyelination seen in ADEM. So we propose that vasculitis and rheumatologic diseases may play role in the pathogenesis of ADEM.

Cytokine responses to resistance training in people with multiple sclerosis

Exercise for individuals with multiple sclerosis (MS) has been shown to improve cardiovascular function, increase strength and endurance, and reduce fatigue. The impact of exercise on immune function in the disease, however, remains mostly unexplored. Ten female MS patients participated in an 8 week programme of twice-weekly progressive resistance training, with pre- and post-training assessment of serum concentrations of cytokines IL-2, IL-4, IL-6, IL-10, CRP, TNF-alpha and IFN-gamma. After training, IL-4, IL-10, CRP and IFN-gamma showed statistically reduced resting concentrations in blood, while TNF-alpha showed non-significant reductions and IL-2 and IL-6 remained unchanged. These results suggest that progressive resistance training may have an impact on cytokine concentrations in individuals with MS and should be confirmed in studies with stronger statistical power. The impact of these changes on overall immune function in MS and on disease status and prognosis remains to be determined.

The clinical importance of neutralizing antibodies in relapsing-remitting multiple sclerosis

BACKGROUND

Neutralizing antibodies (NAbs) develop in patients receiving interferon beta (IFN-beta) for multiple sclerosis (MS). Debate continues concerning the relevance of NAb development on treatment efficacy.

OBJECTIVE

To determine the incidence and clinical importance of NAbs in patients with relapsing-remitting MS (RRMS).

METHODS

A comprehensive literature review was conducted using PubMed (accessed from 1983 to June 2005), Cochrane MS Group trials register (accessed June 2005), MEDLINE (accessed 1983 to June 2005), and Toxnet (accessed June 2005) databases. NAb-induced changes in clinical efficacy and disease progression were evaluated according to the clinical guidelines established by the American Academy of Neurology.

RESULTS

Currently, there is no standardized assay to comparatively assess NAbs among different treatments. NAbs develop independent of age, sex, disease duration and progression index at the onset of treatment. The occurrence of NAbs varies from 2-45% depending on the treatment initiated. NAb+ patients demonstrate accelerated disease progression as confirmed by an approximate 1-point increase in the Expanded Disability Status Scale score. The odds of relapse during a NAb+ period are between 1.51 and 1.58 (p < 0.03) with the time to first relapse being shortened by an average of 244 days after 12 months of IFN-beta therapy. NAb+ patients experience an approximately four-fold increase (p = 0.009) in the median number of active T2 magnetic resonance imaging (MRI) lesions compared to NAb-negative patients (1.4 vs. 0.3 respectively, p < 0.01).

CONCLUSION

The induction of NAbs in IFN-beta treated patients reduce clinical effect and accelerate disease progression.

Proinflammatory cytokines and apoptosis following glutamate-induced excitotoxicity mediated by p38 MAPK in the hippocampus of neonatal rats

The proinflammatory cytokines TNF-alpha, IL-1beta, and IL-6 rise during neuronal damage and activate the apoptotic mitogen-activated protein kinase p38. We studied apoptosis, the levels of TNF-alpha, IL-1beta, and IL-6, and the cell type producing TNF-alpha in rats at 8, 10, and 14 days of age after neonatal exposure to glutamate, which induces neuronal damage. TNF-alpha production was significantly increased by glutamate, but inhibited by SB203580 (a p38 inhibitor). TNF-alpha, IL-1beta, and IL-6 mRNA levels increased, but SB203580 did not modify their expression. Thus, the p38 signaling pathway influences the expression of inflammatory genes and its inhibition may offer anti-inflammatory therapy.

Corticosteroids and Multiple Sclerosis: To Treat or Not to Treat?

Although a rare disease, multiple sclerosis (MS) has a high prevalence rate in Canada and affects many Canadians and their families. An autoimmune disease of the central nervous system, it results in the destruction of the myelin sheath that surrounds the nerve axons. High-dose IV steroid therapy is often used to treat an acute exacerbation in MS. Steroids have immunosuppressant effects that work to decrease the autoimmune pathology component of the disease and to reduce the inflammation around the nerve axon, thereby promoting closer contact of the damaged myelin and subsequently partially restoring adequate electrical nerve conduction to reduce symptoms.

The high prevalence rate of MS in Canada makes it vital for pharmacists to become more aware of the different aspects of the disease and how these relate to therapy. The pharmacist should be aware of the adverse effects and impact of high-dose IV steroids in MS patients. The purpose of this review is threefold: 1) to provide a better understanding of MS pathology; 2) to contribute a systematic review of steroids; and 3) to assist in the clinical decision-making process and in the counselling requirements for patients on high-dose steroids.

Leptin and its soluble receptor in plasma of patients suffering from remitting-relapsing multiple sclerosis (MS) In vitro effects of leptin on type-1 and type-2 cytokine secretion by peripheral blood mononuclear cells, T-cells and monocytes of MS patients

Leptin is synthesized by adipocytes to regulate appetite. Leptin has also been implicated in the pathogenesis of multiple sclerosis (MS) leading to speculation about a beneficial effect of fasting to autoimmune patients. We measured plasma leptin and its soluble receptor (OB-Rs) in 52 MS patients and 50 controls. We also cultured MS and control peripheral blood mononuclear cells (PBMC), T-cells and monocytes +/- recombinant leptin (rleptin), to assess leptin's direct effect on pro- and anti-inflammatory cytokine secretion. We found similar leptin and OB-Rs plasma levels between patients and controls. Untreated patients in the acute phase or in remission, or patients treated with methylprednisolone, had lower leptin levels than patients in the acute phase or in remission receiving IFN-beta. OB-Rs levels were low in patients refractory to IFN-beta but higher in patients receiving methylprednisolone or patients in remission receiving IFN-beta. PBMC from untreated patients in the acute phase, secreted spontaneously IFN-gamma, TNF-alpha and IL-10. IFN-gamma was contributed by T-cells, TNF-alpha and IL-10 primarily by monocytes and to a lesser extent by T-cells. The overall effect of rleptin on PBMC was a net increase in IL-10 production and a net reduction in IFN-gamma production. These results do not warrant a beneficial effect of fasting to MS patients.

In vitro modulation of the multiple sclerosis (MS)-associated retrovirus by cytokines: implications for MS pathogenesis

Multiple sclerosis (MS)-associated retrovirus (MSRV) is a component of the human endogenous retrovirus (HERV)-W family, with gliotoxic and superantigenic properties, related to MS clinical progression, and transactivated by viral agents. The authors studied MSRV modulation by cytokines involved in vivo in MS course, utilizing peripheral blood mononuclear cells from MSRV-positive and MRSV-negative individuals. Cultured cells from MSRV-negative subjects did not produce virus, whereas spontaneous MSRV release was detected in cultures from MSRV-positive donors; virus release was increased by interleukin (IL)-4 and IL-6 and, to a greater extent, by the detrimental cytokines interferon gamma and tumor necrosis factor (TNF)alpha. Interferon beta, used in MS therapy, inhibits MSRV release. A parallel between the effects of these cytokines on MSRV production in vitro and on MS disease in vivo is observed, which deserves further elucidations.