Central memory CD4+ T cells dominate the normal cerebrospinal fluid.

BACKGROUND: To use cerebrospinal fluid (CSF) immune phenotyping as a diagnostic and research tool, we have set out to establish reference values of white blood cell (WBC) subsets in CSF. METHODS: We assessed the absolute numbers and percentages of WBC subsets by 6-color flow cytometry in paired CSF and blood samples of 84 individuals without neurological disease who underwent spinal anaesthesia for surgery. Leukocyte (i.e., lymphocytes, granulocytes, and monocytes), lymphocyte (i.e., T [CD4(+) and CD8(+) ], NK, NKT and B cells), T cell (i.e., naïve, central memory, effector memory, and regulatory) and dendritic cell subsets (i.e., myeloid and plasmacytoid) were studied. RESULTS: CSF showed a predominance of T cells, while granulocytes, B and NK cells were relatively rare compared to blood. The majority of T cells in CSF consisted of CD4(+) T cells (∼70%), most of them (∼90%) with a central memory phenotype, while B cells were almost absent (<1%). Among the small population of dendritic cells in CSF, those of the myeloid subtype were more frequent than plasmacytoid dendritic cells (medians: 1.7% and 0.4% of leukocytes, respectively), whilst both subsets made up 0.2% of leukocytes in blood. CONCLUSIONS: This study reports reference values of absolute numbers and percentages of WBC subsets in CSF, which are essential for further investigation of the immunopathogenesis of neuro-inflammatory diseases. Furthermore, the relative abundance of CD4(+) T cells, mainly with a central memory phenotype, and the presence of dendritic cells in CSF suggests an active adaptive immune response under normal conditions in the central nervous system (CNS).

[Antidote against local anaesthetic intoxication: new use of lipid emulsion for intravenous administration]. / Tegengif voor intoxicatie door lokale anesthetica: nieuwe toepassing van vetemulsie voor intraveneuze toediening.

Local anaesthetics are routinely used for several indications, but despite local administration their use may lead to systemic toxicity. The symptoms include numbness of the tongue, dizziness, tinnitus, visual disturbances, muscle spasms, convulsions, coma, and respiratory and cardiac arrest. Recently, an intravenous lipid emulsion was reported to act as a novel potential antidote for systemic toxicity due to local anaesthetics. We describe the application of this lipid emulsion in a 27-year-old patient with generalized seizures and coma due to local anaesthetic toxicity. She recovered quickly and was responsive again 10 minutes after the intravenous administration of the lipid emulsion.