Classification of cells in the cerebrospinal fluid.

The cells of the cerebrospinal fluid consist of three systems: the lymphatic immune-competent system, the "mononuclear phagocyte system (MPS)" and the reticulo-histiocytic system (RHS). Within the lymphatic cells the lymphocytic line and the plasmocytic line must be considered separately, although the two cell-lines are from their origin functionally inter-connected; they constitute the immune-system. To the "mononuclear phagocyte system" belong the monocytes and the macrophages. The reticulo-histiocytic system includes the cell-forms which are definitely excluded from the "mononuclear phagocyte system". The investigations show that most of the cells in the CSF originate from the blood.