T regulator cell surface antigens in multiple sclerosis

Beta-interferon and multiple sclerosis

Interferon-beta (IFN-beta) is the first therapeutic intervention shown to alter the natural history of multiple sclerosis (MS), a relapsing then progressive inflammatory degenerative disease of the CNS. Since publication of the first randomized placebo-controlled trial of IFN-beta, and subsequent acquisition of US and European product licences for use in relapsing-remitting MS, the hopes and expectations of patients have been elevated greatly only to be dampened as more critical analysis of the trial results, in conjunction with the cost of treatment, led to marked limitations on prescription in several countries. IFN-beta is not a cure. Here we review what is known about the mechanisms of action of IFN-beta in demyelinating disease, and propose a possible model of action of IFN-beta in the treatment of MS.

Immunotherapy of multiple sclerosis

Based on the assumption that multiple sclerosis is an autoimmune disease, a number of clinical trials designed to suppress the immune system or to restore immune balance in multiple sclerosis have been attempted. Depending on the disease category, the clinical goals of immunotherapy differ. Therapeutic goals include improving recovery from acute attacks, preventing or decreasing the number of relapses, and halting the disease in its progressive stage. The ultimate goal of multiple sclerosis therapy is the early treatment of patients in an attempt to halt the onset of progression. Specific strategies of immunotherapy include generation of a suppressor influence, removal of helper/inducer cells, manipulation of activated T cells, manipulation of class II major histocompatibility complex-bearing cells, alteration of lymphocyte traffic, extracorporeal removal of serum factors or cells, and manipulation of antigen-specific cells. Present treatment modalities are beginning to show some efficacy of nonspecific immunosuppression, but these treatments are limited by their toxicities. As the immunotherapy of multiple sclerosis moves to the next stage in the coming years, patients at an earlier stage of their disease will have to be treated, nontoxic forms of therapy developed, clinical trials lengthened, and a laboratory monitor of the disease developed. Given the positive effects of immunotherapy seen thus far in the disease, it is possible that appropriate immunotherapeutic intervention may provide effective treatment for the disease in the future.

Suppressor and cytolytic cell function in multiple sclerosis. Effects of cyclosporine A and interleukin 2

Patients with progressive multiple sclerosis (MS) demonstrated persistent reductions in levels of concanavalin A (Con A)-induced suppressor activity and heightened levels of in vitro pokeweed mitogen (PWM)-induced IgG secretion. The reduced Con A suppressor activity could not be reversed by addition of interleukin 2 (IL-2). Cyclosporine A (CsA) treatment did not alter the defect in Con A-induced suppressor activity, but did markedly inhibit T8+ cell-mediated alloantigen directed cytolytic activity; this latter defect was reversible by in vitro addition of IL-2. CsA-treated patients did not differ from placebo-treated patients with regard to levels of PWM-induced IgG secretion or proliferative responses of their mononuclear cells to Con A. The results indicate that CsA treatment of MS patients reduces cytolytic function from baseline normal values, but does not alter aberrant suppressor cell function.

Progressive multiple sclerosis: abnormal immune functions in vitro and aberrant correlation with enumeration of lymphocyte subpopulations

In a series of 27 consecutive progressive multiple sclerosis (MS) patients under age 50 we have simultaneously measured 3 in vitro immune functions and 6 markers and compared their results to a group of 21 controls. We have confirmed a reduction of concanavalin A (Con A) -induced suppression and NK function contrasting with increased IgG secretion in response to pokeweed mitogen (PWM). Among 6 monoclonal antibody-recognized subpopulation (Leu 1, Leu 2, OKT8, Leu 3, Leu 7 and Leu 11) only Leu 2+ lymphocytes were statistically reduced. OKT8+ were slightly reduced, Leu 3+ were slightly increased. Discriminant analysis revealed that the 3 immune functions together with the results of OKT8 and Leu 3 enumeration were sufficient to appropriately classify most of the individuals. Only 3 MS and 4 controls were misclassified. Correlation analysis suggested disappearance of the doubly labelled OKT8/Leu 7 population in MS patients. In MS as opposed to controls Con A-induced suppression did not correlate with suppressor cell markers but correlated with NK cell markers suggesting that in MS this population mediates Con A-induced suppression. IgG secretion and Con A suppressor cell function were inversely correlated in MS patients but not in controls, suggesting that in chronic progressive multiple sclerosis a common abnormality underlies both increased response to PWM and decreased induction of suppression by Con A.