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The article presents the results of a clinical trial on use of the oral drug laquinimod, an immunomodulatory agent, to treat relapsing-remitting multiple sclerosis (MS). The international selection of patients is described, as is the study design and the evaluation of outcomes using magnetic resonance imaging to detect gladolinium-enhancing (GdE) brain lesions. Patients treated with laquinimod were found to have reductions in brain lesions over 36 weeks, and the drug was well tolerated by most subjects.

Background: There is no consensus method for determining progression of disability in patients with multiple sclerosis (MS) when each patient has had only a single assessment in the course of the disease., Methods: Using data from two large longitudinal databases, the authors tested whether cross-sectional disability assessments are representative of disease severity as a whole. An algorithm, the Multiple Sclerosis Severity Score (MSSS), which relates scores on the Expanded Disability Status Scale (EDSS) to the distribution of disability in patients with comparable disease durations, was devised and then applied to a collection of 9,892 patients from 11 countries to create the Global MSSS. In order to compare different methods of detecting such effects the authors simulated the effects of a genetic factor on disability., Results: Cross-sectional EDSS measurements made after the first year were representative of overall disease severity. The MSSS was more powerful than the other methods the authors tested for detecting different rates of disease progression., Conclusion: The Multiple Sclerosis Severity Score (MSSS) is a powerful method for comparing disease progression using single assessment data. The Global MSSS can be used as a reference table for future disability comparisons. While useful for comparing groups of patients, disease fluctuation precludes its use as a predictor of future disability in an individual.

Objective: To evaluate the rate of shedding of tumor necrosis factor (TNF) receptors (TNFRs) in MS patients., Background: It was previously suggested that TNF might play a significant role in the immunopathologic mechanism of MS. TNF mediates its biologic effects by interacting with two distinct receptors: TNFR-p55 and TNFR-p75. Both of these receptors exist in soluble and membrane-bound forms. Soluble receptors have been shown to influence TNF activity in vitro and in vivo and maintain balance between active, free TNF and inactive form of this cytokine bound to its soluble receptors., Methods: In the current study, the authors measured shedding of TNFRs from cell surface of peripheral blood mononuclear cells, peripheral blood lymphocytes, and monocytes in three groups of MS patients: relapsing-remitting in relapse, relapsing-remitting in remission, and chronic progressive., Results: The authors observed a significant distortion in generation of both soluble TNF receptors. Whereas the TNFR-p55 was shed at lower rate compared with healthy volunteers, the shedding of TNFR-p75 was significantly higher in MS patients., Conclusion: Disturbance in TNFR shedding might contribute to the distortion of a fine balance between circulating TNF and its natural inhibitors in MS.

Intracellular adhesion molecule-1 (ICAM-1) plays an important role in the cascade of adhesion events in the homing of inflammatory cells to the central nervous system (CNS) in experimental autoimmune encephalomyelitis (EAE) and in multiple sclerosis (MS). Two single-base ICAM-1 polymorphisms have been described, in exons 4 and 6, changing codons 241 and 469 in the ICAM-1 gene, respectively. Both polymorphisms result in amino acid changes and can potentially lead to different interactions of ICAM-1 with its ligands. To detect ICAM-1 gene polymorphisms in MS, we have developed a highly sensitive and site-specific, two-stage, nested polymerase chain reaction. Genomic DNA was extracted from blood cells of 79 MS patients and 68 control subjects. The results were confirmed by direct dideoxy chain termination sequencing. The frequency of exon 6 allele T was found to be significantly higher in MS patients than in controls (68% vs 49%). Most interesting, the frequency of exon 6 homozygote K469 was significantly higher in MS patients than in controls (53% vs 34%). Higher frequency of the K469 genotype was found to be independent of possible linkage with the previously described MS susceptibility factor, the HLA class II DR2 allele. In the present study, we have shown for the first time the ICAM-1 gene polymorphisms in MS. The results indicate increased frequency of ICAM-1 exon 6 allele T in MS patients, which may contribute to the MS genetics background.

Multiple sclerosis (MS) is a demyelinating disease in which an inflammatory cell infiltrate represents a characteristic pathologic feature of active lesions within the CNS. The possibility has been raised that cell-mediated immune mechanisms orchestrate the pathogenesis of MS. Cytokines play a particularly important role in cellular immune mechanisms. These soluble glycoproteins, nonimmunoglobulin in nature, act nonenzymatically to regulate immune cell function. A unique family of cytokines, the tumor necrosis factors (TNFs), demonstrate immunoregulatory activity but are also involved in the effector arm of cellular immune responses. Recently, studies both in vitro and in vivo have suggested a role for TNFs in the pathology of MS. This report summarizes data implicating TNFs in the mechanisms of MS and attempts to apply the anti-TNF approach in the future therapeutic strategy for this disease.

The effect of cytokines on astrocytes cultured from mature bovine brain was determined both in a serum-containing medium and in a chemically-defined medium. The results showed that in serum-free medium, human TNF and, to a lesser degree, IL-6 and lymphotoxin, were mitogenic for astrocytes. Increased uptake of [3H]thymidine could be detected within 36 h in vitro and its presence in astrocytes was confirmed by autoradiography. In contrast, neither IL-1 alpha nor IL-1 beta induced astrocyte proliferation in serum-free medium but showed some synergistic effect with serum after 72 h. The proliferative effect of TNF and IL-6 was confirmed by cell counting. None of the cytokines tested was toxic for astrocytes as measured by 51Cr release. No mitogenic effect for oligodendroglia, purified from the same source, was detected. The results support a role for products of activated inflammatory cells in the development of astrocyte proliferation that may contribute to the reactive gliosis found in white matter diseases of the central nervous system such as multiple sclerosis.

Recombinant human tumor necrosis factor (rhTNF) has been tested for its effect on myelinated cultures of mouse spinal cord tissue. As controls, recombinant human interferon gamma (rhIFN) and interleukin-2 (rhIL-2) were tested, as well as T-cell supernatants, antigalactocerebroside serum, and normal culture medium. It was found that rhTNF induced delayed-onset (18-24 hr) oligodendrocyte necrosis and a type of myelin dilatation peculiar to this system. Some nerve fibers progressed to demyelination by 72 hours. The myelin dilatation was not reversible by return to normal feeding solution for 3 days. In contrast, rhIFN, rhIL-2, T-cell supernatants, and normal medium had little or no effect on cultures. This mechanism differs from other immune-mediated mechanisms in that it appears that a physiological (not structural) demyelination occurs initially without overt destruction of the myelin sheath. These observations are relevant to the evolution of the multiple sclerosis plaque: dysfunction of ionic channels might contribute to the eventual demise of oligodendrocytes and axons in the longstanding lesion.