Interferon in the serum and cerebrospinal fluid in patients with multiple sclerosis and other neurological disorders.

The presence of interferon (IF) was investigated in serum and cerebrospinal fluid (CSF) from neurological patients. Significant titres of IF were found both in the serum and in the CSF in about half of the patients suffering from acute encephalitis and from multiple sclerosis (MS), but not in patients suffering from various non-inflammatory disorders in the central nervous system (CNS) or in the peripheral nervous system (PNS), and not in the serum of healthy blood donors. Significant IF titres in the CSF were regularly associated with significant titres in the serum, but the converse was not true. Interferon levels were not correlated to cell counts in the CSF; nor to concentration of IgG and albumin in serum and CSF; nor to presence of electrophoretically oligoclonal IgG patterns; nor to hemagglutinating and gel-precipitation antibodies against measles. IF levels were lower in the serum of patients having reduced serum/CSF ratios for measles antibody than those with normal ratios. The data may indicate that MS is linked to factors which induce IF production in the CNS.