Immunoglobulin synthesis in vitro by cerebrospinal fluid cells in patients with meningoencephalitis of presumed viral origin.

Cerebrospinal fluid (CSF) cells from six patients with meningoencephalitis of presumed viral origin were incubated in the presence of labeled amino acids. The cells of two of the patients synthesized IgG, IgA, and IgM (one patient) in vitro. The CSF of these two patients had an elevated level of IgG with oligoclonal distribution. The newly synthesized IgG also had an oligoclonal distribution. CSF cells of the other four patients were not shown to synthesize immunoglobulins in vitro. The CSF of these patients had a normal level of IgG with polyclonal distribution. The results demonstrate that in some patients with virus meningoencephalitis an immunoglobulin synthesis takes place locally and that at least part of the IgG shows a restricted heterogeneity. The results also suggest the presence of stimulated lymphocytes in the CSF of the same patients.