Regulatory effects of interferon-β on osteopontin and interleukin-17 expression in multiple sclerosis

Biomarkers of Postpartum Depression: A Narrative Review

Postpartum depression (PPD) is a disorder that impairs the formation of the relationship between mother and child, and reduces the quality of life for affected women to a functionally significant degree. Studying markers associated with PPD can help in early detection, prevention, or monitoring treatment. The purpose of this paper is to review biomarkers linked to PPD and to present selected theories on the pathogenesis of the disease based on data from biomarker studies. The complex etiology of the disorder reduces the specificity and sensitivity of markers, but they remain a valuable source of information to help clinicians. The biggest challenge of the future will be to translate high-tech methods for detecting markers associated with postpartum depression into more readily available and less costly ones. Population-based studies are needed to test the utility of potential PPD markers.

An integrated cytokine and kynurenine network as the basis of neuroimmune communication

Two of the molecular families closely associated with mediating communication between the brain and immune system are cytokines and the kynurenine metabolites of tryptophan. Both groups regulate neuron and glial activity in the central nervous system (CNS) and leukocyte function in the immune system, although neither group alone completely explains neuroimmune function, disease occurrence or severity. This essay suggests that the two families perform complementary functions generating an integrated network. The kynurenine pathway determines overall neuronal excitability and plasticity by modulating glutamate receptors and GPR35 activity across the CNS, and regulates general features of immune cell status, surveillance and tolerance which often involves the Aryl Hydrocarbon Receptor (AHR). Equally, cytokines and chemokines define and regulate specific populations of neurons, glia or immune system leukocytes, generating more specific responses within restricted CNS regions or leukocyte populations. In addition, as there is a much larger variety of these compounds, their homing properties enable the superimposition of dynamic variations of cell activity upon local, spatially limited, cell populations. This would in principle allow the targeting of potential treatments to restricted regions of the CNS. The proposed synergistic interface of 'tonic' kynurenine pathway affecting baseline activity and the superimposed 'phasic' cytokine system would constitute an integrated network explaining some features of neuroimmune communication. The concept would broaden the scope for the development of new treatments for disorders involving both the CNS and immune systems, with safer and more effective agents targeted to specific CNS regions.

Emerging Biomarkers of Multiple Sclerosis in the Blood and the CSF: A Focus on Neurofilaments and Therapeutic Considerations

INTRODUCTION

Multiple Sclerosis (MS) is the most common immune-mediated chronic neurodegenerative disease of the central nervous system (CNS) affecting young people. This is due to the permanent disability, cognitive impairment, and the enormous detrimental impact MS can exert on a patient's health-related quality of life. It is of great importance to recognise it in time and commence adequate treatment at an early stage. The currently used disease-modifying therapies (DMT) aim to reduce disease activity and thus halt disability development, which in current clinical practice are monitored by clinical and imaging parameters but not by biomarkers found in blood and/or the cerebrospinal fluid (CSF). Both clinical and radiological measures routinely used to monitor disease activity lack information on the fundamental pathophysiological features and mechanisms of MS. Furthermore, they lag behind the disease process itself. By the time a clinical relapse becomes evident or a new lesion appears on the MRI scan, potentially irreversible damage has already occurred in the CNS. In recent years, several biomarkers that previously have been linked to other neurological and immunological diseases have received increased attention in MS. Additionally, other novel, potential biomarkers with prognostic and diagnostic properties have been detected in the CSF and blood of MS patients.

AREAS COVERED

In this review, we summarise the most up-to-date knowledge and research conducted on the already known and most promising new biomarker candidates found in the CSF and blood of MS patients.

DISCUSSION

the current diagnostic criteria of MS relies on three pillars: MRI imaging, clinical events, and the presence of oligoclonal bands in the CSF (which was reinstated into the diagnostic criteria by the most recent revision). Even though the most recent McDonald criteria made the diagnosis of MS faster than the prior iteration, it is still not an infallible diagnostic toolset, especially at the very early stage of the clinically isolated syndrome. Together with the gold standard MRI and clinical measures, ancillary blood and CSF biomarkers may not just improve diagnostic accuracy and speed but very well may become agents to monitor therapeutic efficacy and make even more personalised treatment in MS a reality in the near future. The major disadvantage of these biomarkers in the past has been the need to obtain CSF to measure them. However, the recent advances in extremely sensitive immunoassays made their measurement possible from peripheral blood even when present only in minuscule concentrations. This should mark the beginning of a new biomarker research and utilisation era in MS.

Plasma IL-17A levels in patients with late-life depression

Objective:

A consistent body of research has confirmed that patients with major depressive disorder (MDD) have increased concentrations of pro-inflammatory cytokines, including IL-6, TNF-α, IL-1β, the soluble IL-2 receptor, and C-reactive protein, compared to controls; however, there is limited information on IL-17A in MDD. Moreover, information about IL-17A in older populations, i.e., patients with late-life depression (LLD), is conspicuously missing from the literature. The purpose of this study was to investigate the role of IL-17A in LLD.

Methods:

A convenience sample of 129 individuals, 74 with LLD and 55 non-depressed controls, were enrolled in this study. The Mann-Whitney U test was used to compare plasma IL-17A levels between LLD and controls subjects, and Spearman’s rank order correlation was used to investigate correlation of these levels with clinical, neuropsychological, and cognitive assessments.

Results:

Plasma IL-17A levels were not statistically different between LLD patients and controls (p = 0.94). Among all subjects (LLD + control), plasma IL-17A did not correlate significantly with depressive symptoms (rho = -0.009, p = 0.92) but a significant correlation was observed with cognitive assessments (rho = 0.22, p = 0.01).

Conclusion:

Our findings do not support an association between plasma IL-17A levels and LLD. Nevertheless, IL-17A may be associated with cognitive impairment in LLD patients. If this finding is confirmed in future longitudinal studies, modulation of the T-helper 17 cell (T_h17) immune response may be a treatment target for cognitive impairment in this population.

Plasma Levels of IL-23 and IL-17 before and after Antidepressant Treatment in Patients with Major Depressive Disorder

OBJECTIVE

Cytokines are believed to have a role in the pathophysiology of major depression. The alteration in levels of pro-inflammatory cytokines [interleukin 1β (IL-1β), IL-2, IL-6, IL-12, interferon γ, and tumor necrosis factor α] in major depression supports the cytokine hypothesis of this illness. IL-23 and IL-17 are also pro-inflammatory cytokines, but few studies have focused on their role in major depression. This study investigated the potential role of the IL-23 and IL-17 axis in major depression.

METHODS

Plasma IL-23 and IL-17 levels were measured in 26 major depressive disorder (MDD) patients before and after 6-week treatment with antidepressants; these levels were measured in 28 age- and sex-matched normal controls. Depression severity was assessed using the Hamilton Depression Rating Scale (HDRS). IL-23 and IL-17 plasma levels were estimated using quantitative enzyme-linked immunosorbent assay.

RESULTS

Pre-treatment plasma levels of IL-23 and IL-17 in MDD patients were not significantly different from those of normal controls. In MDD patients, IL-23 and IL-17 levels after 6 weeks of antidepressant treatment were not different from the baseline levels. There was no significant correlation between changes in the cytokine levels and changes in the HDRS scores representing the severity of depression.

CONCLUSION

The present study does not support a potential involvement of IL-23 and IL-17 axis in major depression. Replication and extension using a larger sample are required.

Plasma osteopontin levels are associated with disease activity in the patients with multiple sclerosis and neuromyelitis optica

Osteopontin (OPN) up-regulates pro-inflammatory cytokines from both T helper type 1 and T helper type 17 cell pathways. We measured plasma OPN levels in Japanese multiple sclerosis (MS) and neuromyelitis optica (NMO) patients to investigate its value as a potential biomarker of disease activity. In NMO patients, plasma OPN levels were significantly higher than those in healthy individuals, being equivalent to those in MS patients. In both NMO and MS patients, OPN levels were significantly higher during relapse compared with remission. There was also a significant positive correlation between Expanded Disability Status Scale of Kurzke scores and plasma OPN levels in both NMO and MS patients, and plasma OPN levels were significantly higher in patients with secondary progressive MS compared with those with relapsing-remitting MS. Diagnostic sensitivity and specificity of plasma OPN for MS and NMO during the relapse phase were 100% and 50%, respectively (cut-off point: 31.3ng/ml). Thus, elevated plasma OPN levels could be a potential biomarker for not only MS but also NMO. These are the first results to suggest that plasma OPN in NMO patients may be a useful marker, playing an important role in inflammation, disease activity, and disease progression, as well as MS.

Vitamin D supplementation for patients with multiple sclerosis treated with interferon-beta: a randomized controlled trial assessing the effect on flu-like symptoms and immunomodulatory properties

BACKGROUND

Flu-like symptoms (FLS) are common side effects of interferon beta (IFN-β) treatment in patients with Multiple Sclerosis (PwMS) and are associated with post-injection cytokine surge. We hypothesized that vitamin D3 supplementation would ameliorate FLS by decreasing related serum cytokines' levels.

METHODS

In a randomized, double blind study of 45 IFNβ-treated PwMS, 21 patients were assigned to 800 IU of vitamin D3 per day (low dose), while 24 patients received 4,370 IU per day (high dose) for one year. FLS were assessed monthly by telephonic interviews. Serum levels of 25-hydroxy-D (25-OH-D), calcium, PTH, IL-17, IL-10 and IFN-γ were measured periodically. EDSS, relapses, adverse events and quality of life (QoL) were documented.

RESULTS

25-OH-D levels increased to a significantly higher levels and PTH levels decreased in the high dose group. There was no significant change in FLS. IL-17 levels were significantly increased in the low dose group, while patients receiving high dose vitamin D had a heterogeneous IL-17 response. No significant differences in relapse rate, EDSS, QoL, serum IL-10 and IFNγ were found. Hypercalcemia or other potential major adverse events were not observed.

CONCLUSION

Vitamin D supplementation to IFN-β treated PwMS, at the doses used, seems safe and associated with dose-dependent changes in IL-17 serum levels, while not affecting IFN-β related FLS.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT01005095.

Longitudinal interferon-β effects in multiple sclerosis: differential regulation of IL-10 and IL-17A, while no sustained effects on IFN-γ, IL-4 or IL-13

BACKGROUND

Recent studies in experimental models and in vitro indicate lowering of IL-17/Th17 as an important mechanism of interferon-beta (IFN-β) treatment in multiple sclerosis (MS).

MATERIAL AND METHODS

In this longitudinal study of MS patients (n=25), spontaneous and myelin antigen-induced secretion of IL-4, IFN-γ and IL-10 (ELISPOT), mitogen stimulated secretion of IL-13 and IL-17A (ELISA) and circulating cytokine levels (Luminex) were recorded at inclusion and after 1.5, 3, 6 and 12months of IFN-β treatment.

RESULTS

Early changes were noted for IL-4, while after one year of treatment the only recorded significant effects were a decrease in secreted IL-17A levels and an increase in IL-10 secreting cells. While IL-17A levels tended to be higher in non-responders (n=8), the decrease in IL-17A levels seemed to be more pronounced in responders (n=17) showing significantly lower IL-17A levels after one year as compared with non-responders.

CONCLUSION

IFN-β treatment seems to mainly affect IL-17/IL-10-associated pathways rather than the IFN-γ/IL-4 axis.

Blockade of osteopontin reduces alloreactive CD8+ T cell-mediated graft-versus-host disease

Graft-versus-host disease (GVHD), a life-threatening complication after allogeneic hematopoietic stem cell transplantation, is caused by alloreactive donor T cells that trigger host tissue damage. The inflammatory environment inside recipients is critical for GVHD pathogenesis, but the underpinning mechanisms remain elusive. Using mouse model of human GVHD, we demonstrate osteopontin (OPN), a potent proinflammatory cytokine, plays an important role in regulating activation, migration, and survival of alloreactive T cells during GVHD. OPN was significantly elevated after irradiation and persisted throughout the course of GVHD. Blockade of OPN attenuated GVHD with reduced accumulation of donor T cells in recipient organs. Amelioration was the result of migration and survival suppression caused by anti-OPN treatment on donor-derived T cells for 2 reasons. First, OPN promoted the migration and infiltration of naive and alloreactive CD8(+) T cells into host organs. Second, it also facilitated activation and viability of donor-derived CD8(+) T cells via synergizing with T-cell receptor/CD3 signaling. Finally, anti-OPN treatment retained graft-versus-leukemia effect of alloreactive CD8(+) T cells. This study demonstrates, to our knowledge for the first time, the critical effect of OPN in the initiation and persistence of CD8(+) T cell-mediated GVHD and validates OPN as a potential target in GVHD prevention.