MOLECULAR-DETECTION OF INTERFERON-ALPHA EXPRESSION IN MULTIPLE-SCLEROSIS BRAIN

The demonstration of intermittent interferonaemia in patients with mul tiple sclerosis prompted a molecular analysis of brain tissue for expr ession of interferon-alpha genes. A sensitive method was developed bas ed on the polymerase chain reaction. Primer sets were used that could amplify all interferons-alpha or two particular subtypes, interferon-a lpha2 and interferon-alpha4. The procedure was successful in detecting expression of interferons-alpha in brain and non-brain tissues in mos t patients with multiple sclerosis. However, expression was demonstrab le also in a similar proportion of patients with other neural diseases , and patients with other illnesses. The data indicate that there can be constitutive expression of interferons-alpha in brain tissue, but t he possibility that this becomes amplified in multiple sclerosis was n ot revealed by this study.