Local Synthesis in the Central Nervous System of Diclonal IgM-kappa and Homogeneous Free kappa Light Chain Proteins in a Case of Chronic Meningoencephalitis

Abstract

A 60-year-old man with chronic meningoencephalitis and mononuclear pleocytosis of the CSF was observed for 22 months. About one half of the CSF cells were concluded to represent IgM-synthesizing lymphocytes and plasma cells. Electrophoretic analysis disclosed two abnormal protein bands in the CSF. The bands were shown to be composed of a diclonal IgMK protein and a homogeneous Kfree light chain protein. No abnormal immunoglobulins were detected in serum or urine. The pleocytosis and immunoglobulin abnormalities of the CSF persisted during the observation period. Specific antibody activity of the diclonal IgM of the CSF was not demonstrated and the cause of the illness remains unknown.