Immunological study of IFNbeta-1a-treated and untreated multiple sclerosis patients: clarifying IFNbeta mechanisms and establishing specific dendritic cell immunotherapy

Modulating acute neuroinflammation in intracerebral hemorrhage: the potential promise of currently approved medications for multiple sclerosis

The secondary inflammatory injury following intracerebral hemorrhage (ICH) results in increased morbidity and mortality. White blood cells have been implicated as critical mediators of this inflammatory injury. Currently, no medications have been clinically proven to ameliorate or beneficially modulate inflammation, or to improve outcomes by any mechanism, following ICH. However, other neuroinflammatory conditions, such as multiple sclerosis, have approved pharmacologic therapies that modulate the inflammatory response and minimize the damage caused by inflammatory cells. Thus, there is substantial interest in existing therapies for neuroinflammation and their potential applicability to other acute neurological diseases such as ICH. In this review, we examined the mechanism of action of twelve currently approved medications for multiple sclerosis: alemtuzumab, daclizumab, dimethyl fumarate, fingolimod, glatiramer acetate, interferon beta-1a, interferon beta-1b, mitoxantrone, natalizumab, ocrelizumab, rituximab, teriflunomide. We analyzed the existing literature pertaining to the effects of these medications on various leukocytes and also with emphasis on mechanisms of action during the acute period following initiation of therapy. As a result, we provide a valuable summary of the current body of knowledge regarding these therapies and evidence that supports or refutes their likely promise for treating neuroinflammation following ICH.

Evaluation of protective effect of IL-22 and IL-12 on cutaneous leishmaniasis in BALB/c mice

OBJECTIVE

To investigate the protective effect of IL-22 and IL-12 on cutaneous leishmaniasisin BALB/c mice.

METHODS

The protective effect of IL-22 and IL-12 on cutaneous leishmanias in BALB/c mice was evaluated by measurement of IL-4, INF-γ, total IgG, IgG1 and IgG2a after challenge with Leishamania major. Clinical evaluations were performed by measurement of lesion diameter, and survival rate of the mice.

RESULTS

In week 27 post infection, the mortality rates for control groups were 100%. While the survival rates for the IL-12, IL-12 + IL-22, and IL-22(5 ng/g) groups were 100%. The size of lesions decreased in the presence IL-22 (5 ng/g) of mice weight, which was statistically significant in comparison with other groups (P<0.05). Mean of total IgG, IgG1 and IgG2a for IL-22 (5 ng/g) group was more than other groups. In IL-22 group (5 ng/g), INF-γ production was significantly higher than other groups and IL-4 was significantly lower than other groups.

CONCLUSIONS

The results obtained indicate the effectiveness of IL-22 and its effect on IL-12 in protection of cutaneous leishmaniasis.

Combined exercise training reduces IFN-γ and IL-17 levels in the plasma and the supernatant of peripheral blood mononuclear cells in women with multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disorder in which lymphocytic infiltration mediated mainly by pro-inflammatory cytokines. In this study, we examined the effect of combined exercise training on the levels of IFN-γ, IL-4 and IL-17 in the plasma and the supernatant of peripheral blood lymphocytes in women with multiple sclerosis. Expanded Disability Status Scale (EDSS), VO(2)max, muscle strength, and balance tests were obtained at baseline and post-treatment follow-up. Combined exercises training was designed for 24 sessions during 8 weeks. Each session was started with 5 min warm-up and was followed by 10 min stretch training, 20 min aerobic exercises and 20 min resistance-endurance training. The disability score was significantly decreased in test MS subjects after 8 weeks combined exercise training. Muscle strength and balance were increased significantly after the training program in test group. In this study, plasma, and peripheral blood mononuclear cell (PBMC) IL-17 and IFN-γ production was significantly decreased after 8 weeks combined training. Our findings suggest that combined training has useful anti-inflammatory effects by decrease in PBMC and plasma IL-17 production.

The role of dendritic cells in CNS autoimmunity

Multiple sclerosis (MS) is a chronic immune-mediated, central nervous system (CNS) demyelinating disease. Clinical and histopathological features suggest an inflammatory etiology involving resident CNS innate cells as well as invading adaptive immune cells. Encephalitogenic myelin-reactive T cells have been implicated in the initiation of an inflammatory cascade, eventually resulting in demyelination and axonal damage (the histological hallmarks of MS). Dendritic cells (DC) have recently emerged as key modulators of this immunopathological cascade, as supported by studies in humans and experimental disease models. In one such model, experimental autoimmune encephalomyelitis (EAE), CNS microvessel-associated DC have been shown to be essential for local antigen recognition by myelin-reactive T cells. Moreover, the functional state and compartmental distribution of DC derived from CNS and associated lymphatics seem to be limiting factors in both the induction and effector phases of EAE. Moreover, DC modulate and balance the recruitment of encephalitogenic and regulatory T cells into CNS tissue. This capacity is critically influenced by DC surface expression of co-stimulatory or co-inhibitory molecules. The fact that DC accumulate in the CNS before T cells and can direct T-cell responses suggests that they are key determinants of CNS autoimmune outcomes. Here we provide a comprehensive review of recent advances in our understanding of CNS-derived DC and their relevance to neuroinflammation.

The role of regulatory T cells in multiple sclerosis

The dysregulation of inflammatory responses and of immune self-tolerance is considered to be a key element in the autoreactive immune response in multiple sclerosis (MS). Regulatory T (T(REG)) cells have emerged as crucial players in the pathogenetic scenario of CNS autoimmune inflammation. Targeted deletion of T(REG) cells causes spontaneous autoimmune disease in mice, whereas augmentation of T(REG)-cell function can prevent the development of or alleviate variants of experimental autoimmune encephalomyelitis, the animal model of MS. Recent findings indicate that MS itself is also accompanied by dysfunction or impaired maturation of T(REG) cells. The development and function of T(REG) cells is closely linked to dendritic cells (DCs), which have a central role in the activation and reactivation of encephalitogenic cells in the CNS. DCs and T(REG) cells have an intimate bidirectional relationship, and, in combination with other factors and cell types, certain types of DCs are capable of inducing T(REG) cells. Consequently, T(REG) cells and DCs have been recognized as potential therapeutic targets in MS. This Review compiles the current knowledge on the role and function of various subsets of T(REG) cells in MS and experimental autoimmune encephalomyelitis. We also highlight the role of tolerogenic DCs and their bidirectional interaction with T(REG) cells during CNS autoimmunity.

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.

Type I Interferons Attenuate T Cell Activating Functions of Human Mast Cells by Decreasing TNF-α Production and OX40 Ligand Expression While Increasing IL-10 Production

Recent studies have demonstrated that mast cells not only mediate inflammatory reactions in type I allergy but also play an important role in adaptive immunity. In the present study, we investigated the effects of interferon-alpha, which shares the same receptor as IFN-beta, on human cord blood-derived mast cells. Mast cells produced TNF-alpha, and IL-10, and expressed OX40 ligand upon activation by crosslinking of FcepsilonRI. When treated with interferon-alpha, TNF-alpha production was decreased while IL-10 and TGF-beta productions were increased. Furthermore, flow cytometric analysis revealed that interferon-alpha downregulated expression OX40 ligand on mast cells which is crucial for mast cell-T cell interaction. We confirmed that the viability of mast cells was not affected by interferon-alpha treatment. Accordingly, interferon-alpha-treated mast cells induced lower levels of CD4+ T cell proliferation compared with those without interferon-alpha treatment. These results suggest that type I interferons suppress T cell immune responses through their regulatory effects on mast cells.

CD30 antigen and multiple sclerosis: CD30, an important costimulatory molecule and marker of a regulatory subpopulation of dendritic cells, is involved in the maintenance of the physiological balance between TH1/TH2 immune responses and tolerance. The role of IFNbeta-1a in the treatment of multiple sclerosis

OBJECTIVES

The immunological effect of CD30 on dendritic cells (DCs) was examined in a comparative study of patients with relapsing-remitting multiple sclerosis (RRMS). The patients were divided into two groups on the basis of interferon (IFN)beta-1a treatment: IFNbeta-1a-treated patients and untreated patients. We have already shown that CD30 is a marker of cells involved in the regulation of the balance between TH1 and TH2 immune responses and so the aim of this study was to confirm this role in DCs and, consequently, to clarify the immunopathological mechanisms of MS and the causes of immunosuppressive drug failure.

METHODS

We studied network interactions between soluble (s) CD30 and TH1/TH2 cytokines in the supernatants of CD14+-derived immature DC (IDC) and DC cultures from treated and untreated patients. Network interactions between the sCD30 and cytokines in IDC and DC supernatants were also evaluated in relation to TH1/TH2 cytokine serum levels.

RESULTS

Our overall results show that CD30 is expressed on IDCs and DCs, indicating an immunological role in resting and activated physiological conditions. This role would appear to be the regulation of the resting and activated physiological balance between the TH1/TH2 immune functions as abnormal increases in sCD30 levels result in impaired regulation. Further studies are undoubtedly required to clarify this situation. IFNbeta-1a treatment was found to determine a fall in sCD30 levels, leading to the restoration of the normal functional selection of IDCs from progenitor cells and the regulation of the TH1/TH2 network balance. However, IFNbeta-1a treatment may also be responsible for the in vivo suppression of CD30-mediated TH1-DC functions in immune activation. TH1-DC functions are involved in the induction of T-regulatory cells for the physiological deletion of self-aggressive cells.

CONCLUSION

We conclude that CD30 is an important costimulatory molecule and marker of a regulatory subpopulation of DCs which induces and modulates immune cells involved in the maintenance of the physiological balance between TH1/TH2 immune responses and tolerance. Elucidating the mechanisms restoring DC and T-regulatory cell function could lead to more effective therapy and strategies for the prevention and treatment of immunopathological conditions such as autoimmunity, transplant rejection, allergy and tumors.