IFN-beta1a and IFN-beta1b have different patterns of influence on cytokines

MicroRNAs: Potential Biomarkers of Disease Severity in Chronic Rhinosinusitis with Nasal Polyps

Background and Objectives: Chronic rhinosinusitis with nasal polyps (CRwNP) has multiple clinical presentations, and predictors of successful treatment are correlated to different parameters. Differentially expressed microRNAs in nasal polyps emerge as possible facilitators of precise endotyping in this disease. We aimed to evaluate the correlation between the clinical parameters of CRSwNP and two different microRNAs. Materials and Methods: The expression of miR-125b and miR-203a-3p in nasal polyps (n = 86) and normal nasal mucosa (n = 20) was determined through microarray analysis. Preoperative workup included CT scan, nasal endoscopy, blood tests, symptoms and depression questionnaires. Results: MiR-125b showed significant overexpression in NP compared to the normal nasal mucosa. miR-125b expression levels were positively and significantly correlated with blood eosinophilia (p = 0.018) and nasal endoscopy score (p = 0.021). Although high CT scores were related to miR-125b overexpression, the correlation did not reach statistical significance. miR-203a-3p was underexpressed in nasal polyps and was significantly underexpressed in CRSwNP patients with environmental allergies. Conclusions: Both miR-125b and miR-203a-3p are potential biomarkers in CRSwNP. miR-125b also correlates with the clinical picture, while miR-203a-3p could help identify an associated allergy.

Hematological Abnormalities in COVID-19 Disease: Association With Type I Interferon Pathway Activation and Disease Outcomes

Increased expression of interferon (IFN)-stimulated genes (ISGs) in peripheral blood, has been previously reported in viral infections, as well as in autoimmune disorders, in association with reduced leukocyte and platelet counts. Though cytopenias are common in patients with COVID-19 disease and predict severe outcomes, the underlying mechanisms have not been fully elucidated. In the current study, we aimed to determine the prevalence of hematological abnormalities in the setting of active COVID-19 infection and to explore whether they associate with disease outcomes and activation of type I IFN pathway. One-hundred-twenty-three consecutive SARS-CoV2 infected patients were included in the study. Clinical and laboratory parameters were recorded for all study participants. In 114 patients, total RNA was extracted from whole peripheral blood and subjected to real time PCR. The relative expression of three interferon stimulated genes (ISGs; IFIT1, MX-1, and IFI44) was determined and a type I IFN score reflecting peripheral type I IFN activity was calculated. The rates of anemia, leukopenia, and thrombocytopenia were 28.5, 14.6, and 24.4%, respectively. Among leukocytopenias, eosinopenia, and lymphopenia were the most prominent abnormalities being found in 56.9 and 43.1%, respectively. Of interest, patients with either eosinopenia and/or thrombocytopenia but no other hematological abnormalities displayed significantly increased peripheral type I IFN scores compared to their counterparts with normal/high eosinophil and platelet counts. While eosinopenia along with lymphopenia were found to be associated with increased risk for intubation and severe/critical disease, such an association was not detected between other hematological abnormalities or increased type I IFN scores. In conclusion, hematological abnormalities are commonly detected among patients with COVID-19 infection in association with severe disease outcomes and activation of the type I IFN pathway.

Gene expression of semaphorin-3A, semaphorin-7A, neuropilin-1, plexin-C1, and β1 integrin in treated-multiple sclerosis patients

OBJECTIVE

Recently, members of the semaphorin family have received major attention in various medical fields, especially autoimmunity. In this study, we selected semaphorin-3A (Sema3A), semaphorin-7A (Sema7A), and their receptors to determine the possible relationship between these molecules and multiple sclerosis (MS).

METHOD

We measured the gene expression of Sema3A, Sema7A, neuropilin-1 (NP-1), plexin-C1, and β1 integrin in the blood samples of relapsing-remitting multiple sclerosis (RRMS) patients, treated with high-dose interferon-β1a (IFN-β1a), low-dose IFN-β1a, IFN-β1b, and glatiramer acetate (GA) via quantitative real-time polymerase chain reaction (qRT-PCR) assay, and then, compared the results of treatment-naive patients with the healthy controls.

RESULTS

The gene expression of Sema3A (P = 0.02), NP-1 (P < 0.001), and plexin-C1 (P < 0.01) significantly decreased in the treatment-naive group, compared to the healthy controls. Sema3A significantly increased in all treated patients, compared to the treatment-naive patients (P < 0.001). However, expression of NP-1 (P < 0.001), plexin-C1 (P < 0.001), and β1 integrin (P < 0.05) only increased in patients receiving high-dose IFN-β1a, IFN-β1b, and GA. Expression of Sema7A increased in only two groups of patients treated with IFN-β1b (P < 0.001) and GA (P = 0.018), without any significant decrease in the treatment-naive group, compared to the healthy controls (P > 0.05).

CONCLUSION

Our findings confirm that the presence of Sema3A, Sema7A, and their receptors can play critical roles in the treatment of MS patients. Therefore, they can be potential target molecules for MS treatment in the future.

Enhanced Interferon-β Response Contributes to Eosinophilic Chronic Rhinosinusitis

Type I interferon (IFN-I, including IFN-α and IFN-β) response has been implicated in eosinophilic inflammation, in addition to antiviral function. This study aimed to investigate the role of IFN-I in the pathogenesis of eosinophilic chronic rhinosinusitis (ECRS). IFN-α, IFN-β, cytokine expression, and IFN-β cellular localization in the sinonasal tissue from control subjects and ECRS patients with nasal polyps (NP) were determined using real time-PCR, ELISA, and immunohistochemistry. ECRS was induced in wild-type (WT) and IFNAR1 knockout (Ifnar1^−/−) mice by intranasal challenge with Aspergillus protease and ovalbumin. Stromal cells cultured from NP tissue were stimulated by exogenous IFN-β, and their CCL11 production and IRF3, IRF7, STAT1, STAT2, and IRF9 gene and/or protein expression were measured. IFN-β, IL-5, IL-13, and CCL11 expression was higher in the NP tissue from ECRS patients, compared to the control group. IFN-β was highly colocalized with the CD11c+ cells in NP. IFN-β levels positively correlated with IL-5, IL-13, and CCL11 levels as well as the number of eosinophils in the NP tissue and CT score. The histological severity of ECRS, levels of IL-4, IL-5, IL-13, and CCL11 in the nasal lavage fluid, and total serum IgE levels were less in Ifnar1^−/− mice than in WT mice. CCL11 production, and STAT1 and STAT2 mRNA and STAT1, phospho-STAT1, and phospho-STAT2 protein expression were significantly increased by exogenous IFN-β in NP stromal cells. Our data suggest that IFN-β response was upregulated in ECRS and may play role in ECRS development. IFN-β may contribute to ECRS by enhancing CCL11 production. Thus, increased IFN-β response in the sinonasal mucosa may underlie ECRS pathogenesis.

Salivary IL-1ß as an Objective Measure for Fatigue in Multiple Sclerosis?

Background: The causes of fatigue in multiple sclerosis (MS) and other inflammatory disorders are not well understood. One possible cause that might explain fatigue in inflammatory disorders appears to be the immunological process itself, triggering neural activity that is experienced as fatigue.

Objectives: To investigate whether salivary IL-1ß concentration, associated with systemic inflammation, is related to subjective fatigue in MS.

Methods: 116 MS patients (62 relapsing remitting MS, 54 secondary progressive MS) and 51 healthy controls participated in this study. Salivary concentration of IL-1ß was determined using a commercially available enzyme-linked immunosorbent assay (ELISA) kit. Fatigue was assessed using various fatigue scales. We compared IL-1ß concentration between groups and performed regression analyses to investigate which variables best predict fatigue scores.

Results: We found that the IL-1ß concentration best predicts fatigue scores in relapsing remitting MS patients, even though the IL-1ß concentration did not differ significantly between relapsing remitting MS patients and healthy controls. Secondary progressive MS patients showed a somewhat elevated IL-1ß concentration compared to relapsing remitting MS patients and healthy controls. Furthermore, disease modifying treatment had a significant effect on the IL-1ß concentration, with treated patients showing a lower IL-1ß concentration than non-treated patients.

Conclusions: The present study points to a significant relation between the proinflammatory cytokine IL-1ß and fatigue in relapsing remitting MS patients. It also suggests a potential effect of disease modifying treatment on the peripheral IL-1ß concentration.

PI3K pathway inhibitors: potential prospects as adjuncts to vaccine immunotherapy for glioblastoma

Constitutive activation of the PI3K pathway has been implicated in glioblastoma (GBM) pathogenesis. Pharmacologic inhibition can both inhibit tumor survival and downregulate expression of programmed death ligand-1, a protein highly expressed on glioma cells that strongly contributes to cancer immunosuppression. In that manner, PI3K pathway inhibitors can help optimize GBM vaccine immunotherapy. In this review, we describe and assess the potential integration of various classes of PI3K pathway inhibitors into GBM immunotherapy. While early-generation inhibitors have a wide range of immunosuppressive effects that could negate their antitumor potency, further work should better characterize how contemporary inhibitors affect the immune response. This will help determine if these inhibitors are truly a therapeutic avenue with a strong future in GBM immunotherapy.

IFN-α/β receptor signaling promotes regulatory T cell development and function under stress conditions

Type I IFNs are a family of cytokines with antiviral and immunomodulatory properties. Although the antiviral effects of IFNs are well characterized, their immunomodulatory properties are less clear. To specifically address the effects of type I IFNs on T regulatory cells (Tregs), we studied mixed bone marrow chimeras between wild-type and IFN-α/β receptor (IFNAR) knockout (KO) mice, and heterozygous female mice expressing a Treg-specific deletion of the IFNAR. In these two models, IFNAR signaling promotes the development of the Treg lineage in the thymus and their survival in the periphery. IFNAR KO Tregs had a higher expression of the proapoptotic gene Bim and higher frequency of active caspase-positive cells. IFNAR KO Tregs from chimeric mice displayed a more naive phenotype, accompanied by lower levels of CD25 and phosphorylated STAT5. Therefore, in Tregs, IFNAR signaling may directly or indirectly affect phosphorylation of STAT5. In mixed chimeras with Scurfy fetal liver, Tregs derived from IFNAR KO bone marrow were unable to control T effector cell activation and tissue inflammation. Under stress conditions or in a competitive environment, IFNAR signaling may be required to maintain Treg homeostasis and function.

Formal modelling of toll like receptor 4 and JAK/STAT signalling pathways: insight into the roles of SOCS-1, interferon-β and proinflammatory cytokines in sepsis

Sepsis is one of the major causes of human morbidity and results in a considerable number of deaths each year. Lipopolysaccharide-induced sepsis has been associated with TLR4 signalling pathway which in collaboration with the JAK/STAT signalling regulate endotoxemia and inflammation. However, during sepsis our immune system cannot maintain a balance of cytokine levels and results in multiple organ damage and eventual death. Different opinions have been made in previous studies about the expression patterns and the role of proinflammatory cytokines in sepsis that attracted our attention towards qualitative properties of TLR4 and JAK/STAT signalling pathways using computer-aided studies. René Thomas' formalism was used to model septic and non-septic dynamics of TLR4 and JAK/STAT signalling. Comparisons among dynamics were made by intervening or removing the specific interactions among entities. Among our predictions, recurrent induction of proinflammatory cytokines with subsequent downregulation was found as the basic characteristic of septic model. This characteristic was found in agreement with previous experimental studies, which implicate that inflammation is followed by immunomodulation in septic patients. Moreover, intervention in downregulation of proinflammatory cytokines by SOCS-1 was found desirable to boost the immune responses. On the other hand, interventions either in TLR4 or transcriptional elements such as NFκB and STAT were found effective in the downregulation of immune responses. Whereas, IFN-β and SOCS-1 mediated downregulation at different levels of signalling were found to be associated with variations in the levels of proinflammatory cytokines. However, these predictions need to be further validated using wet laboratory experimental studies to further explore the roles of inhibitors such as SOCS-1 and IFN-β, which may alter the levels of proinflammatory cytokines at different stages of sepsis.

Effect of interferon beta-1a on B7.1 and B7.2 B-cell expression and its impact on T-cell proliferation

The effect of pharmacologically relevant doses of interferon (IFN) β-1a on B-cell expression of B7.1 and B7.2 was investigated. Culture of peripheral blood mononuclear cells with IFN β-1a 100 IU/mL decreased B-cell expression of B7.1 and increased B7.2 expression. Interleukin-10 in B cells was significantly enhanced by IFN β-1a. Anti-CD3 and anti-CD28 monoclonal antibody-mediated T-cell proliferations were partially suppressed in the presence of B cells pretreated with IFN β-1a. These data suggest that IFN β-1a and B cells can interact to play a beneficial role in the treatment of multiple sclerosis.

Interferon beta and glatiramer acetate therapy

Interferon beta and glatiramer acetate have been mainstays of treatment in relapsingremitting multiple sclerosis for two decades. Remarkable advances in our understanding of immune function and dysfunction as well as increasingly sophisticated clinical trial design have stemmed from efforts to better understand these drugs. In this chapter, we review the history of their development and elaborate on known and theorized mechanisms of action. We describe the pivotal clinical trials that have led to their widespread use. We evaluate the clinical use of the drugs including tolerability, side effects, and efficacy measures. Finally, we look to the future of interferon beta and glatiramer acetate in the context of an ever growing armamentarium of treatments for relapsing remitting multiple sclerosis.

Interferon-β1b increases Th2 response in neuromyelitis optica

A Japanese randomized controlled study showed that Interferon â (IFN-â1b) therapy is clinically effective in decreasing the frequency of attacks in multiple sclerosis (MS), even in optico-spinal MS (OSMS). However, recent studies have shown that IFN-â (IFN-â1a/IFN-â1b) treatment was not effective in neuromyelitis optica (NMO) patients and that the diminished benefit of IFN-â treatment in NMO may be due to different immune responses to IFN-â. We determined longitudinally the expression of CCR5, CXCR3 and CCR4 on CD4+ T and CD8+ T cells in the blood from patients with NMO and MS treated with IFN-â1b. During a 12-month period of IFN-â1b therapy, the annualized relapse rate decreased in MS patients but not in NMO patients. There was no significant difference in the expression of the chemokine receptors between NMO and MS at baseline. The percentages of CD4+CCR5+ and CD4+CXCR3+ T cells, representative of the Th1 response, were decreased in both NMO and MS after treatment. The percentage of CD4+CCR4+ T cells, representative of the Th2 response, was decreased in MS, but those for NMO was significantly increased compared with the pretreatment levels. Our results indicate that IFN-â1b-induced up-modulation of the Th2 response in NMO patients may be the source of differences in the therapeutic response to IFN-â1b therapy. In the present study, Th2 predominance is involved in the pathogenesis of NMO.

TH1/TH2 Cytokine profile in relapsing-remitting multiple sclerosis patients treated with Glatiramer acetate or Natalizumab

Background

The balance between T helper cells Th2- and Th1-related cytokines plays a key role in multiple sclerosis (MS). A shift from a Th1 towards a Th2 cytokine profile could have a beneficial effect on the clinical course of the disease. The objective of this study was to assess Th2/Th1 cytokine profile in relapsing-remitting MS (RRMS) patients receiving an immunosuppressive treatment with natalizumab (NAT), or an immunomodulatory treatment with glatiramer acetate (GA) after one year of treatment.

Methods

This was an observational cross-sectional study. All consecutive patients diagnosed with RRMS who had received GA or NAT for 12 months were included in the study. We determined serum levels of Th1 and Th2 cytokines (interleukin [IL]-1a, IL-1b, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-13, monocyte chemotactic protein [MCP]-1, tumor-necrosis factor [TNF]-α, interferon [IFN]-γ and granulocyte macrophage colony stimulating factor [GM-CSF]) by flow cytometry. Th2/Th1 bias was defined based on the ratio of IL-4, IL-5, IL-6 or IL-10 Th2 cytokines and proinflammatory INF-γ or TNF-α Th1 cytokines.

Results

Eleven patients under treatment with NAT and 12 patients treated with GA were evaluated. RRMS patients treated with NAT showed significantly higher levels of IL-6 (p < 0.05), MCP-1 (p < 0.01), and GM-CSF (p < 0.05) compared to GA patients after one year of treatment. A trend for increasing of IL-12p70, IL-1b, TNF- α and IFN- γ levels was also found in patients receiving NAT compared to GA patients. IL-4/IFN-γ, IFN-γ/TNF-α and IL-10/IFN-γ ratios as markers of Th2/Th1 ratio were significantly elevated in GA patients compared to those receiving NAT (p < 0.05).

Conclusion

In conclusion, our findings suggest that GA promotes a superior Th2-biased anti-inflammatory response as compared with NAT in the systemic circulation of RRMS patients. Future studies with larger cohorts will determine whether this immune Th2 shift in GA patients is associated with a beneficial effect on disease outcome.

Frequency and severity of headache is worsened by Interferon-β therapy in patients with multiple sclerosis

BACKGROUND

The relationship between multiple sclerosis (MS) and headache (HA) is not well known. It was reported that interferon-beta (IFNβ) could induce or worsen HA.

OBJECTIVE

To evaluate the impact of IFNβ treatment on HA and the relationship between HA and the various commercial preparations of IFNβ in mildly disabled patients with MS.

METHODS

A specific questionnaire was administered to 357 relapsing-remitting MS patients. Characteristics of HAs were considered, including the temporal relationships with IFNβ administration.

RESULTS

One hundred and seventeen patients were treated with weekly intramuscular injections of interferon IFNβ-1a (Avonex(®)), 84 with subcutaneous injections of IFNβ-1b (Betaferon(®)) every other day, 48 and 108 with three times weekly subcutaneous injections of IFNβ-1a (Rebif(®)) 22 mcg or IFNβ-1a (Rebif(®)) 44 mcg, respectively. Three hundred and fourteen patients were affected by HA, and among them, 219 patients suffered of pre-existing HA. In this latter group, 121 subjects (55%) noted a worsening of their HA after starting IFNβ therapy; this was more frequently reported by patients treated with Avonex(®) and Rebif(®) 44. Ninety-five patients experienced new HA.

CONCLUSION

IFNβ treatment could worsen HA in patients with pre-existing HA or cause the appearance of new HA. Among different IFNβ preparations, Rebif(®) 44 and Avonex(®) seemed to be more cephalalgic than the other drugs.

Overexpression of miR-125b, a novel regulator of innate immunity, in eosinophilic chronic rhinosinusitis with nasal polyps

RATIONALE

Eosinophilic chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) represents a hard-to-treat subtype of CRS.

OBJECTIVES

To determine the pattern of expression and biologic role of microRNAs (miRNAs) in CRS, particularly in eosinophilic CRSwNP.

METHODS

Global miRNA expression in sinonasal mucosa from controls, CRS without nasal polyps (CRSsNP), and patients with eosinophilic CRSwNP was compared using miRNA microarrays. MiR-125b expression was detected by means of quantitative reverse-transcriptase polymerase chain reaction. The cellular localization of miR-125b was determined by in situ hybridization. MiR-125b functional assays were performed on airway epithelial cells and mice. MiR-125b expression regulation was studied by tissue and cell culture.

MEASUREMENTS AND MAIN RESULTS

CRSsNP and eosinophilic CRSwNP exhibited distinct miRNA expression profiles. MiR-125b was specifically up-regulated in eosinophilic CRSwNP. MiR-125b was mainly expressed by sinonasal and bronchial epithelial cells. EIF4E-binding protein 1 (4E-BP1) was identified as a direct target of miR-125b. MiR-125b mimic or inhibitor enhanced or decreased IFN-α/β production elicited by dsRNA in vitro or in vivo, respectively. 4E-BP1 expression was decreased, whereas IFN regulatory factor-7 and IFN-β expression was increased, in eosinophilic CRSwNP. IFN-β mRNA levels positively correlated with IL-5 mRNA levels and eosinophil infiltration in sinonasal mucosa. IFN-β stimulated B cell-activating factor of the tumor necrosis factor family production in airway epithelial cells. miR-125b could be induced by lipopolysaccharide, dsRNA, and IL-10.

CONCLUSIONS

The up-regulated expression of miR-125b may enhance type I IFN expression through suppressing 4E-BP1 protein expression in airway epithelial cells, which potentially contributes to mucosal eosinophilia in eosinophilic CRSwNP.

Treatment with natalizumab in relapsing-remitting multiple sclerosis patients induces changes in inflammatory mechanism

Natalizumab is a widely accepted drug for the relapsing–remitting subtype of multiple sclerosis (RRMS). The present longitudinal exploratory study in RRMS patients analyzes the effects of natalizumab treatment on the levels of pro-inflammatory and anti-inflammatory cytokine protein levels and also the frequency and suppressor function of regulatory T cells. Flow cytometry was used to determine cytokines and regulatory T cell frequency while regulatory T cell suppressor function was assayed in vitro at different time-points after starting with natalizumab. Results showed serum levels of pro-inflammatory interferon gamma and interleukin (IL)-12p70, as well as anti-inflammatory IL-4 and IL-10, were elevated just a few hours or days after first IV infusion of natalizumab. Interestingly, other cytokines like IL-5 or IL-13 were also elevated while pro-inflammatory IL-17, IL-2, and IL-1β increased only after a long-term treatment, suggesting different immune mechanisms. In contrast, we did not observe any effect of natalizumab treatment on regulatory T cell frequency or activity. In conclusion, these results suggest natalizumab has other immunological effects beyond VLA-4 interaction and inhibition of CNS extravasation, the relevance of which is as yet unknown and warrants further investigation.

Clinical effects and tolerability of high-dose, high-frequency recombinant interferon beta-1a in patients with multiple sclerosis: maximizing therapy through long-term adherence

IMPORTANCE OF THE FIELD

High-dose, high-frequency IFN beta-1a in multiple sclerosis (MS) can prevent lesion formation, decrease the frequency/severity of relapses and delay progression of disability, with a proven safety profile. Rates of non-adherence are high. There are drugs under investigation that may have greater efficacy and different safety profiles from existing therapies.

AREAS COVERED IN THIS REVIEW

Evidence supporting the efficacy of IFN beta-1a, factors contributing to non-adherence, and strategies to combat non-adherence. It is hoped that these strategies, coupled with future advances in pharmacogenetics, might lead to better outcomes. The PubMed database was searched using the terms "multiple sclerosis" and "interferon beta-1a", for papers published between 1998 and 2010. Relevant manuscripts and pivotal papers from clinical trials were cited. Searches of abstracts from congresses were also performed to obtain recent findings.

WHAT THE READER WILL GAIN

An overview of early pivotal trials, comparative studies with other treatments, and recent studies assessing the development of this therapy.

TAKE HOME MESSAGE

Long-term treatment with IFN beta-1a has benefits in MS and a good safety profile. Although adherence outside of clinical trials can be poor, injection devices, better tolerated drug formulations and education regarding treatment expectations are some of the strategies employed to help patients to adhere to treatment in the hope of improving outcomes.

Influence of conjugated linoleic acid on the porcine immune response and morbidity: a randomized controlled trial

Background

Conjugated linoleic acid (CLA) has diverse influences on the immune response in different experimental models. In the present study we investigated the effect of CLA feeding on inflammatory and immune responses in a piglet model. We studied the duration of this effect and possible detrimental effects of CLA feeding. After 12 weeks of CLA and control supplementation and washout, animals were sacrificed and parenchymal organs were histologically examined.

Results

In activated peripheral mononuclear cells interferon-γ was significantly (p = 0.008) lower in the CLA group by the end of the feeding period. This effect disappeared as soon as supplementation was stopped. No differences were found in the tumour necrosis factor-α, interleukin-10 production, serum immunoglobulin-G levels and fat infiltration of the liver, except that fat storage cell infiltration was significantly (p < 0.04) higher in the CLA-fed group. The effect of time for interferon-γ, interleukin-10 and immunoglobulin-G levels was statistically significant.

Conclusion

At the end of the feeding period the interferon-γ response was depressed. However, the maturation of the piglet immune system in our young pig model probably outweighs the impact of CLA feeding on the immune response, even though liver fat storage cell infiltration, which plays an important role in liver regeneration, increased during CLA feeding of the piglets.

High-dose, high-frequency recombinant interferon beta-1a in the treatment of multiple sclerosis

BACKGROUND

There is at present no cure for multiple sclerosis (MS), and existing therapies are designed primarily to prevent lesion formation, decrease the rate and severity of relapses and delay the resulting disability by reducing levels of inflammation.

OBJECTIVE

The aim of this review was to assess the treatment of relapsing MS with particular focus on subcutaneous (s.c.) interferon (IFN) beta-1a.

METHOD

The literature on IFN beta-1a therapy of MS was reviewed based on a PubMed search (English-language publications from 1990) including its pharmacodynamics and pharmacokinetics, clinical efficacy in relapsing MS as shown in placebo-controlled studies and in comparative trials, efficacy in secondary progressive MS, safety and tolerability, and the impact of neutralizing antibodies.

CONCLUSION

The literature suggests that high-dose, high-frequency s.c. IFN beta-1a offers an effective option for treating patients with relapsing MS, with proven long-term safety and tolerability, and has a favourable benefit-to-risk ratio compared with other forms of IFN beta.

Effect of treatment with methylprednisolone on the serum levels of IL-12, IL-10 and CCL2 chemokine in patients with multiple sclerosis in relapse

OBJECTIVES

Interleukin-12 (IL-12), a proinflammatory cytokine produced by Th1 cells, and interleukin-10 (IL-10), a product of Th2 cells, are involved in the pathogenetic mechanisms of multiple sclerosis (MS). CCL2 chemokine expression is induced by Th2 cytokines and is decreased in MS relapse. The mechanisms responsible for the beneficial effects of IVmethylprednisolone in attacks are not clearly established and the duration of the effect of this treatment remains controversial.

PATIENTS AND METHODS

We measured by enzyme-like immunosorbent assay (ELISA) serum levels of IL-12, IL-10 and CCL2 before, 5 days and 1 month after the initiation of treatment with IVMP in 20 patients with MS in relapse.

RESULTS

A significant increase of IL-10 and decrease of CCL2 serum levels was observed (p=0.0028 and 0.045 respectively) five days after the onset of steroid treatment but not after one month. Steroid treatment had no influence in serum levels of IL-12.

CONCLUSIONS

The clinical improvement of our MS patients with relapse following the treatment with methylprednisolone may be associated with an immediate but not a long-term modification of serum levels of IL-10 and CCL2. IL-12 may not be influenced by steroid treatment.

Pharmacokinetics and pharmacodynamics of the interferon-betas, glatiramer acetate, and mitoxantrone in multiple sclerosis

Five disease-modifying agents are currently approved for long-term treatment of multiple sclerosis (MS), namely three interferon-beta preparations, glatiramer acetate, and mitoxantrone(1). Pharmacokinetics describes the fate of drugs in the human body by studying their absorption, distribution, metabolism and excretion. Pharmacodynamics is dedicated to the mechanisms of action of drugs. The understanding of the pharmacokinetics and pharmacodynamics of the approved disease-modifying agents against MS is of importance as it might contribute to the development of future derivatives with a potentially higher efficacy and a more favourable safety profile. This article reviews data thus far present both on the pharmacokinetics as well as on the putative mechanisms of action of the interferon-betas, glatiramer acetate, and mitoxantrone in the immunopathogenesis of MS.

Cytokine changes during interferon-beta therapy in multiple sclerosis: correlations with interferon dose and MRI response

We investigated serum (IL-10 and IL-12p70) and cellular cytokine levels (IL-10, IL-12p40, IL-12p70, IFN-gamma) in stimulated PBMC over 24 weeks in 15 relapsing-remitting multiple sclerosis (MS) patients randomized to receive once-weekly (qw) IFN-beta-1a 30 microg intramuscularly (IM) (n=8) or three-times-weekly (tiw) IFN-beta-1a 44 microg subcutaneously (SC) (n=7). Overall, IFN-beta treatment increased cellular IL-10 (p<0.01) levels and the ratios of cellular IL-10/IL-12p40 (p<0.01) and IL-10/IL-12p70 (p<0.02) while cellular IFN-gamma levels were reduced (p<0.01). Serum IL-10 levels were decreased in non-responders to therapy based on MRI-defined criteria (p<0.01) but did not change in responders over the course of treatment. In addition, non-responders demonstrated a decrease in serum IL-10/IL-12p70 ratio (p=0.031) and a decrease in cellular IL-12p70 (p<0.02). A decrease in cellular IFN-gamma was observed in responders (p=0.013). This is the first study that compares cytokine changes between the two IFN-beta regimes and demonstrates that serum IL-10 levels decrease in those patients who continue to have active MRI lesions while on interferon-beta therapy.

Interferon-beta mediates opposing effects on interferon-gamma-dependent Interleukin-12 p70 secretion by human monocyte-derived dendritic cells

Interferon-beta (IFN-beta) exposure during tumour necrosis factor-alpha (TNF-alpha)-induced human monocyte-derived dendritic cell (DC) maturation augments the capacity of DC to promote the generation of T helper 1 (Th1) cells, while IFN-beta exposure during naive Th cell stimulation inhibits Th1 cell generation (Nagai et al., J Immunol, 2003 171:5233-43). Investigating these contradictory outcomes of IFN-beta exposure, we find that isolated DC matured with both TNF-alpha and IFN-beta secrete more IL-12 p70 upon CD40L stimulation than DC matured with TNF-alpha alone. mAb blocking studies indicate that the basis for this enhanced IL-12 p70 production is augmentation of two successive CD40-dependent autocrine pathways in the DC: (1) a pathway in which low levels of IL-12 p70, IL-27, IL-18 and, possibly, IL-23 act to mediate autocrine induction of DC IFN-gamma secretion; and (2) an IFN-gamma-initiated autocrine pathway promoting optimal DC IL-12 p70 secretion. In contrast to the IL-12 p70 promoting effects of IFN-beta during DC maturation, IFN-beta pre-treatment before CD40L stimulation was found to inhibit IFN-gamma-mediated enhancement of DC IL-12 p70 secretion. Thus, IFN-beta exposure during TNF-alpha-mediated DC maturation may promote Th1 polarization by increasing DC IL-12 p70 secretion, through enhancement of autocrine-acting IFN-gamma production by the DC. Moreover, IFN-beta exposure during naive Th cell stimulation may inhibit Th1 cell generation by blocking the IFN-gamma-induced signals required for optimal CD40L-induced DC IL-12 p70 secretion. IFN-beta pre-treatment was also observed to inhibit CD40L-induced DC IL-23 secretion. Our findings may account for some of the beneficial effects of IFN-beta therapy in patients with relapsing remitting multiple sclerosis.

Long-term favorable response to interferon beta-1b is linked to cytokine deviation toward the Th2 and Tc2 sides in Japanese patients with multiple sclerosis

To address the immune mechanism of the long-term beneficial effects of interferon beta (IFN-beta), we measured the intracellular cytokine production patterns of IFN-gamma, IL-4 and IL-13 in peripheral blood CD4+ and CD8+ T cells, which previously displayed alterations during the early course of IFN-beta treatment, in 15 Japanese patients after long-term IFN-beta administration. The patients were treated with IFN-beta-1b 8 x 10(6) units given subcutaneously every other day for a mean period of 34.5 +/- 5.5 months (range: 26-43 months). During the follow-up period, 6 patients experienced 33 relapses, while the other 9 were relapse-free. The results revealed the following cytokine alterations: (1) type 2 cytokine, such as IL-4 and IL-13, were significantly increased in producing cell percentages in both CD4+ (p = 0.0356 and p = 0.0007, respectively) and CD8+ (p = 0.0231 and p = 0.0170, respectively) T cells while IFN-gamma, a representative type 1 cytokine, was significantly decreased in the absolute producing cell numbers (p = 0.0125 in CD4+ T cells and p = 0.0022 in CD8+ T cells) even after approximately 3 years of IFN-beta administration; (2) the intracellular IFN-gamma / IL-4 ratio tended to decrease in both CD4+ and CD8+ T cells (p = 0.0535 and p = 0.0783, respectively), reflecting a strong downmodulation of type 1 cytokine producing cells; and importantly (3) alterations such as the decreased intracellular IFN-gamma / IL-4 ratio in CD4+ T cells and increased percentage of CD8+ IL-13+ T cells compared with the pretreatment levels were only statistically significant in MS patients without relapse during IFN-beta therapy (p = 0.0152 and p = 0.0078, respectively). Therefore, we consider that cytokine deviation toward the Th2 and Tc2 sides is linked to a long-term favorable response to IFN-beta, while a higher intracellular IFN-gamma / IL-4 ratio is associated with treatment failure.

Mechanisms of action for treatments in multiple sclerosis: Does a heterogeneous disease demand a multi-targeted therapeutic approach?

The etiology of multiple sclerosis (MS) is incompletely understood, and evidence suggests there may be more than one underlying cause in this disorder. Furthermore, this complex and heterogeneous autoimmune disease shows a high degree of clinical variability between patients. Therefore, in the absence of a single therapeutic target for MS, it is difficult to apply conventional drug design strategies in the search for new treatments. We review the potential mechanisms of action of several effective therapies for MS that are currently available or in development. The effects of each treatment are described in terms of their actions on key processes in a five-step model of MS pathogenesis. Conventional immunosuppressants targeting intracellular ligands (e.g. mitoxantrone) have broad cytotoxic effects on B cells, T cells, and macrophages. This suppresses the pathogenic immune response in MS with high efficacy but is also associated with high toxicity, limiting the long-term use of these agents. Monoclonal antibodies (e.g. natalizumab and alemtuzumab) are a new generation of immunosuppressants that act on immune-cell surface ligands. These agents have narrower immunosuppressive actions and different safety profiles compared with conventional immunosuppressants. Immunomodulators (interferon-beta and glatiramer acetate), which shift the immune balance toward an anti-inflammatory response, are at the frontline of treatments for MS. Immunomodulators have targeted actions on the immune system, but affect a greater number of immunopathogenic processes than monoclonal antibodies. Given the inherent heterogeneity of MS, such treatments, which act at many levels of the disease, may achieve the best clinical results. Using our understanding of the interplay between mechanism of action and clinical effects in MS therapies may help us to better design and select new treatments for the future.