[Demyelination in in vitro culture in multiple sclerosis: facts and controversies]

The myelinotoxicity of sera from multiple sclerosis (MS) patients was determined by the assessment of visible myelin damage in guinea-pig spinal cord-spinal ganglia and in rat cerebella cultivated on collagen-coated coverslips in Leighton tubes. No change was seen in 22 cases. These data show that serum myelinotoxicity is low in MS - as compared with that of Experimental Allergic Encephalomyelitis. It appears a little specific phenomenon, the mechanism of which remains unclear. It can be easily assessed only in very sensitive culture techniques and is best measured by biochemical methods. This does not preclude the pathophysiological significance of the serum myelinotoxicity in MS. Supernatants of cerebro-spinal fluid (CSF) cell cultures in 10 MS patients caused no demyelination. Pooled concentrated supernatants of CSF cell cultures from 13 to 20 MS patients--containing from 7.3 to 11.7 micrograms IgG/ml gave no patent in vitro demyelination in 3 different experiments. The released products of CSF cell cultures in MS are not very toxic for myelin. However these experiments have to be repeated with more sensitive culture techniques, biochemical assay of myelinotoxicity and more concentrated CSF cultures supernatants.