Cerebrospinal fluid lymphocytes from patients with multiple sclerosis do not increase immunoglobulin or measles antibody production after stimulation with pokeweed mitogen.

Cerebrospinal fluid lymphocytes (CSF-L) and peripheral blood lymphocytes (PBL) from patients with multiple sclerosis (MS) and acute aseptic meningoencephalitis (AM) were cultured without and in the presence of pokeweed mitogen (PWM), a polyclonal B cell activator. IgG, IgA and IgM as well as measles IgG antibody production was measured in 7-day-culture supernatants by enzyme-linked immunosorbent assay. MS CSF-L did not respond with increased Ig production after PWM stimulation, in contrast to AM CSF-L which responded to PWM with a modest increase of production of all 3 Ig classes, especially IgG. PBL responded to PWM with a pronounced production of IgG, IgA and especially IgM, showing no difference between MS, AM and healthy controls. CSF-L from only 1 of 7 patients with MS showed increased measles IgG antibody production after PWM stimulation. The poor response of MS CSF-L might be due to maximal activation of B lymphocytes in vivo, thereby limiting further Ig production after stimulation in vitro.