GENE POLYMORPHISM AT POSITION -308 OF THE TUMOR-NECROSIS-FACTOR-ALPHA(TNF-ALPHA) IN MULTIPLE-SCLEROSIS AND ITS INFLUENCE ON THE REGULATIONOF TNF-ALPHA PRODUCTION

Tumor-necrosis-factor-alpha (TNF-alpha) is a major mediator of the inf lammatory immune response and may play an important role in the pathog enesis and progression of Multiple Sclerosis (MS). Increased TNF-alpha levels of cerebrospinal fluid (CSF) and peripheral blood were found i n patients with chronic progressive MS and patients with acute relapse s, but not in the stable form of the disease. Considering the associat ion of different TNF-alpha alleles with diverse autoimmune diseases we sequenced the TNF-alpha promotor region (-674 to +201) of 23 patients with relapsing/remitting MS, of 27 patients with chronic progressive MS (21 patients had primary progressive course and six patients had a secondary progressive course) and of 22 healthy controls, who had no h istory of MS in their families. In three of 21 patients (14%) with pri mary chronic progressive MS a homozygous point-mutation at position -3 08 could be demonstrated where guanine (G) was substituted by adenosin e (A). This mutation could neither be detected in patients with relaps ing/remitting MS nor in healthy controls. However, 40% of the patients with relapsing/remitting MS and 43% of the primary chronic progressiv e MS patients were heterozygous at position -308 for G/A, whereas only 32% of healthy controls showed this heterogeneity. The genetic variat ions were demonstrated by polymerase chain reaction (PCR)-amplificatio n of the TNF-alpha promotor-region and consecutive direct automatic se quencing. Functional analysis of the promoter region using the chloram phenicol-acetyltransferase (CAT) assay revealed spontaneous production with the homozygous mutation at -308 only.