Lactobacilli as antigen delivery system for mucosal tolerance induction in autoimmune disease : Lactobacillen als systeem voor produktie, transport en afgifte van antigeen voor de inductie van mucosale tolerantie in autoimmuunziekten

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (eNS) that affects eNS myelin which isolates nerve axons and allows saltatory pulse conduction. It is the most important chronic disabling neurological disease in young adults, with a mean age of onset around 30 years. It has a prevalence of approximately I per 1000 in Western European countries and it affects women versus men at a ratio of 1.5 to I (Sadovnick and Ebers, 1993). Although the cause and pathogenesis of MS are unknown, it is generally believed that MS is an autoimmune disease in which environmental factors as well as genetic factors are involved. Studies with monozygotic twins reveal an MS concordance rate of 20-30%, ·whereas this is 3-5% for dizygotic twins (reviewed by Ebers and Sadovnick, 1994). This high concordance rate is a strong argument in favor of a genetic basis of MS, but can also be used as an argument for an environmental involvement in MS. The role of environmental factors in MS is supported by the presence of geographic gradients in the distribution of the disease. The general pattern is that MS prevalence rises with increasing distance from the equator. The nature of these environmental factors is unknown. Dietary factors, climate variation and infectious agents have all been postulated to be involved in MS, but there is no definitive proof for involvement in MS of any of these factors. Especially herpes viruses have gained interest the last few years (Dalgleish, 1997). The notion that MS is a multifactorial disease is strengthened by the fact that the clinical course of MS is highly variable for each individual patient, and can be divided into four categories (Lublin and Reingold, 1996). The first category is relapsingremitting disease, in which discrete attacks are alternated with periods in which a patient returns to the pre-attack base line. In the relapsing-progressive form of MS, the patients do not return to base-line level in between attacks and disability increases in these patients. In chronic-progressive disease, the disease progresses without periods of stability. The uncommon fourth form is characterized by a progressive relapsing course of MS