Fine analysis of cytolytic and natural killer T lymphocytes in the CSF in multiple sclerosis and other neurologic diseases.

Cytolytic T lymphocyte precursors (CTL-p) and natural killer precursors (NK-p) in the CSF of 15 MS patients and 11 patients with other neurologic disorders (OND) were quantitatively assessed, using a T-lymphocyte microculture system that allows clonal expansion of all human T cells. CSF CTL-p and NK-p frequencies were higher in patients with OND of inflammatory nature than in patients with noninflammatory OND. In all MS patients, these frequencies were higher in the CSF than in their peripheral blood. Surprisingly, in all patients studied, the CSF contained a substantial number of CTL-p with a helper (CD4+) phenotype.