Estimation of C3 levels in cerebrospinal fluid by electroimmunodiffusion.

C3 levels have been determined by the electroimmunodiffusion technique in the CSF of patients with a wide variety of pathologies. The patients were grouped on the basis of protein content and G/A ratio of the CSF as I) patients with normal meningeal permeability and apparent absence of local gamma-globulin synthesis; II) patients with increased meningeal permeability; III) patients with characteristics of MS, i.e. increase of IgG accompanied by a normal or slightly elevated protein content, Group III showed a lower level of C3 when expressed at % of the total protein and also as % of the total protein less gamma-globulins of the CSF. Other parameters of the CSF are also recorded. It was shown that only the expression of C3 concentration relative to the total protein content of the CSF produced meaningful analytical data.