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Objective: Mitoxantrone is an antineoplastic agent also used for the treatment of multiple sclerosis (MS). However, despite its efficacy, few data are available on its mechanism of action. The current study was designed to evaluate the short-term (1 month) and long-term (12 months) in vivo effects of mitoxantrone on pro- and anti-inflammatory cytokine production by the peripheral blood mononuclear cells (PBMC) of secondary progressive MS patients., Methods: Eighteen patients with secondary progressive MS underwent mitoxantrone therapy (at a dose of 12 mg/m(2) once every 3 months) over a 1-year period. Blood samples were obtained at baseline, after 1 month and after 12 months of treatment. The production of cytokines in the PBMC was measured by enzyme-linked immunosorbent assay., Results: There were no significant effects of mitoxantrone on proinflammatory cytokines [interleukin (IL) 6 and IL-12p40] and anti-inflammatory cytokines (IL-10 and transforming growth factor-beta) in our patients. Patients who showed no signs of therapeutic response were characterized by a higher basal PBMC production of IL-6 compared with that of the responding patients (p < 0.05) and mitoxantrone reduced this production after 12 months of treatment (p < 0.05). In the responding patients, IL-10 was significantly increased by mitoxantrone after 12 months of treatment (p < 0.05)., Conclusion: These findings provide additional information useful in the selection of the patient population suitable for mitoxantrone treatment and suggest that most probably the therapeutic action of mitoxantrone in MS is not entirely mediated by its immunosuppressant effects.

Leptin is a peptide hormone which acts on cells of immune system by influencing the production of cytokines. Serum leptin levels and cytokine production by peripheral blood mononuclear cells (PBMC) were measured in 18 secondary progressive multiple sclerosis (SPMS) patients under IFN-beta-1b treatment. There were no overall effects on leptin, interleukin-6 (IL-6), IL-10 and IL-12 p40 after 2, 6 and 12 months of treatment. However, leptin and IL-6 decreased after 6 and 12 months of treatment in 12 patients who did not show progression of disability. Thus, our pilot data show that the beneficial effect of IFN-beta on some SPMS patients might be associated with the reduced levels of leptin and reduced IL-6 production by PBMC.

Antibodies against myelin oligodendrocyte antigens have been found in the immunoreactive brain lesions of Multiple Sclerosis (MS) patients. Recently it has been proposed that these antibodies can be used as a prognostic marker in the course of disease. However, the serum levels of these autoantibodies during different phases of disease activity or after an immunomodulatory therapy have been poorly investigated. In this study the serum levels of anti-myelin oligodendrocyte glycoprotein (MOG) (directed against the epitopes 1-26 and 15-40) and anti-myelin basic protein (MBP) antibodies were sequentially measured in the same MS patient either in relapse or remission phases. We found that MS patients in the relapse phase had higher serum anti-MOG (peptides 1-26 and 15-40) and anti-MBP antibody levels than controls. In addition, the levels of anti-MOG 1-26 were also elevated during the relapse as compared with the remission phase but no significant changes were found in the levels of anti-MOG 15-40 of anti-MBP antibodies. We also evaluated the effect of interferon-beta (beta) therapy on anti-myelin antibodies. 1-year of interferon-beta treatment did not induce any changes in the levels of anti-MOG and anti-MBP antibodies. In conclusion, these data indicate that the use of peripheral levels of autoantibodies against MOG and MBP as marker of multiple sclerosis might be complicated by the phase of disease activity and by the epitope of the MOG protein used.

Leptin, a hormone synthesized mainly by adipocytes, can modulate the immune response and seems to be involved in the induction of experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis (MS). However, the possible role of leptin in MS pathogenesis has not yet been elucidated. In this study we investigated the effect of leptin on cytokine production by peripheral blood mononuclear cells (PBMCs) of MS patients (either in the acute or in the stable phase of the disease) and healthy controls. We also analyzed leptin effects on cytokine production by monocytes in relapsing MS patients. Our data showed that leptin induced tumor necrosis factor-alpha, interleukin-6, and interleukin-10 production by PBMCs of patients in an acute phase of disease but not in patients in a stable phase or in healthy controls. Moreover, we found no effect of leptin in monocytes from relapsing MS patients. Therefore we conclude that leptin may modulate the MS inflammatory process during relapses.

The role of leptin was investigated in relapsing-remitting multiple sclerosis (MS). Control and MS patients showed comparable baseline serum leptin levels. During the first year of IFNbeta-1a treatment, leptin significantly decreased since 2 months after starting therapy in 11 patients who had no relapses. A significant decrease in IL12/IL10 ratio was observed in this group of patients only after 1 year of treatment. An increase of leptin was observed before the first clinical exacerbation in 13 relapsing patients. Leptin may play a pathogenic role in MS and can be a useful marker of disease activity and response to therapy.