Flow cytometric cerebrospinal fluid analysis in children

Promise, Progress, and Pitfalls in the Search for Central Nervous System Biomarkers in Neuroimmunological Diseases: A Role for Cerebrospinal Fluid Immunophenotyping

Biomarkers are central to the translational medicine strategic focus, though strict criteria need to be applied to their designation and utility. They are one of the most promising areas of medical research, but the "biomarker life-cycle" must be understood to avoid false-positive and false-negative results. Molecular biomarkers will revolutionize the treatment of neurological diseases, but the rate of progress depends on a bold, visionary stance by neurologists, as well as scientists, biotech and pharmaceutical industries, funding agencies, and regulators. One important tool in studying cell-specific biomarkers is multiparameter flow cytometry. Cerebrospinal fluid immunophenotyping, or immune phenotypic subsets, captures the biology of intrathecal inflammatory processes, and has the potential to guide personalized immunotherapeutic selection and monitor treatment efficacy. Though data exist for some disorders, they are surprisingly lacking in many others, identifying a serious deficit to be overcome. Flow cytometric immunophenotyping provides a valuable, available, and feasible "window" into both adaptive and innate components of neuroinflammation that is currently underutilized.

Expanding the spectrum of neurological disease associated with Epstein-Barr virus activity

The purpose of this study was to delineate the spectrum of neurological diseases attributed to Epstein-Barr virus (EBV) activity. The approach was a retrospective study on patients with EBV activity proven by a positive EBV antibody-specific index (AI) and/or cerebrospinal fluid (CSF) PCR. One hundred six children and adults (AI positive = 77, AI + PCR positive = 3, PCR positive = 26) were identified, most with reactivated infections. Twenty-eight showed typical EBV-related diseases (encephalitis, neuritis, meningitis), 19 further infections (HSV encephalitis, neuroborreliosis, HIV infection, bacterial meningitis), nine immune-mediated disorders (multiple sclerosis, optic neuritis), and 50 further diseases not typical for EBV. The highest AI values occurred in patients with encephalitis. No relationship between disease category or AI values and viral loads was found. Additional reanalysis of 1,500 consecutive CSF EBV PCR studies revealed the highest positive rates among patients with further infections (n = 18/227, 7.9%) but lower rates among patients with typical EBV-related disorders (5/395; 1.3%), immune-mediated disorders (n = 2/174; 1.1%) and other conditions (n = 4/704; 0.6%). Intrathecal EBV activity is not restricted to typical EBV-related disorders, unexpectedly frequent in further CNS infections and also present in non-inflammatory conditions. Prospective studies should assess the pathogenic role of EBV in these different diseases.

Naive and Memory CD4+T-cells in the Cerebrospinal Fluid of Children with Aseptic Meningitis Following Measles-Mumps-Rubella Vaccination and Enteroviral Meningitis

We investigated the distribution of memory (CD45RO+) and naive (CD45RA+CD62L+) CD4+ T-cells as well as CD8+ T-cells and total T-cells in the CSF of children with aseptic meningitis following measles-mumps-rubella (MMW) vaccination and those with enteroviral meningitis. Flow cytometric analysis of CSF cells was performed in 12 children with MMR vaccine-associated meningitis and 11 children with enteroviral meningitis. Percentages of total T-cells, CD4+ and CD8+ T-cells and monocytes in CSF of patients from the two groups were not significantly different. The majority of CD4+ T-cells in the CSF of both patient groups were of memory phenotype. Percentages of CSF naive CD4+ T-cells were increased in children with aseptic meningitis following MMR vaccination. Further studies focused on the more detailed immunophenotyping of CSF cells are needed to fully establish the usefulness of flow cytometry in the diagnostic workup of inflammatory CNS diseases in children.

Analysis of cerebrospinal fluid cell populations with monoclonal antibodies

Sixty-five samples of cerebrospinal fluid (CSF) were evaluated using an automated cytoflow method with the CD-Sapphire hematology analyzer in order to investigate possible relationships between cell population patterns and diagnostic groups and better understand the biology of neurological disease. A basic panel of CD markers, including CD3/4/8/19/138/HLA-DR, was used to analyze CSF samples from clinical and laboratory confirmed cases of multiple sclerosis, neuroborreliosis, viral and bacterial neuroinfective diseases, malignant infiltrations of meninges and scavenger macrophagic reactions of the central nervous system. The principles of immune response and the contribution of cytological 'disease-related patterns' for these nosological entities are described. The distinct patterns of lymphocyte subpopulations in neuroborreliosis appear to be characteristic and could possibly serve as diagnostic indicators. Further verification and research will be necessary to clarify the significance and nature of CD4+ CD8+ positive subset in cerebrospinal fluid.