Blood and cerebrospinal fluid immune cell profiles in patients with temporal lobe epilepsy of different etiologies.

Inflammation plays a role in the pathogenesis of immune-mediated epilepsy, but also in epilepsy of other etiology such as hippocampal sclerosis. This study aimed to characterize immune cell signatures in the peripheral blood (PB) and cerebrospinal fluid (CSF) in temporal lobe epilepsy (TLE) of different etiologies. We retrospectively evaluated CSF routine parameters and immune cell profiles using flow cytometry in a cohort of 51 patients and 45 age-matched controls with functional disorders. Groups were comprised of patients with nonlesional TLE (n = 26), TLE due to hippocampal sclerosis (n = 14), or limbic encephalitis with antibodies against the 65-kDa isoform of glutamic acid decarboxylase (GAD65-LE; n = 11). TLE patients showed increased proportions of human leukocyte antigen-DR isotype (HLA-DR)-expressing CD4+ T lymphocytes in the CSF. Furthermore, they were characterized by a shift in monocyte subsets toward immature CD14low CD16+ cells in the PB and blood/CSF-barrier dysfunction. Whereas TLE patients in general showed similar immune cell profiles, patients with GAD65-LE differed from other TLE patients by increased proportions of HLA-DR-expressing CD8+ T lymphocytes and type 2/3 oligoclonal bands. These findings point to a role of innate and adaptive immunity in TLE. CSF parameters may help to discriminate epilepsy patients from controls and different forms of TLE from each other.

A rapid method for preparation of the cerebrospinal fluid proteome.

The cerebrospinal fluid (CSF) proteome is of great interest for investigation of diseases and conditions involving the CNS. However, the presence of high-abundance proteins (HAPs) can interfere with the detection of low-abundance proteins, potentially hindering the discovery of new biomarkers. Therefore, an assessment of the CSF subproteome composition requires depletion strategies. Existing methods are time consuming, often involving multistep protocols. Here, we present a rapid, accurate, and reproducible method for preparing the CSF proteome, which allows the identification of a high number of proteins. This method involves acetonitrile (ACN) precipitation for depleting HAPs, followed by immediate trypsination. As an example, we demonstrate that this method allows discrimination between multiple sclerosis patients and healthy subjects.

[A very curious electrophoresis]. / Une bien curieuse électrophorèse.

Preanalytical steps may be the source of many errors. In this paper, we report the case of an exploration of cerebrospinal fluid (CSF) proteins in which the pre-analytical step was defective. Discordance in the results of the CSF protein level measurement, associated with an aberrant electrophoresis led us to suspect a preanalytical interference. After investigating the preanalytical treatment of the sample, we suspected a possible interference by previous formaldehyde treatment, which was confirmed by several tests performed in our laboratory. These data point out the importance of preanalytical steps for the quality of results.

An extensive search for autoantibodies to myelin basic protein in cerebrospinal fluid of non-multiple-sclerosis patients: implications for the pathogenesis of multiple sclerosis.

Inflammation of multiple sclerosis (MS) brain and spinal cord tissue consists of macrophages, T lymphocytes and cytokines as well as B lymphocytes and immunoglobulins (IgGs). IgG can be detected in high concentrations in both central nervous system tissue and cerebrospinal fluid (CSF). Using a sensitive radioimmunoassay (RIA), autoantibodies to myelin basic protein (anti-MBP) can be detected in the CSF of 90-95% of MS patients with active disease. The purpose of the present report was to determine whether these same autoantibodies can be reliably detected in non-MS patients. Between 1978 and 1998, CSF was collected from 1,968 control non-MS patients with psychiatric, inflammatory and noninflammatory neurological diseases as well as nonneurological systemic diseases, and anti-MBP were measured by the same RIA used to detect anti-MBP in MS CSF. Anti-MBP were undetectable in 98% of CSF samples from non-MS controls. In the remaining 2% of control samples, CSF IgGs capable of binding to MBP in vitro were unpredictably detected. This latter group included 1% of patients with miscellaneous diseases such as encephalomyelitis, 5 siblings with familial spastic paraparesis, rare patients with strokes, Wernicke-Korsakoff's syndrome, inherited leukodystrophy, motor neuron disease and some patients with miscellaneous spinal cord diseases. An additional 1% of patients included a group with neurological symptoms suggestive of early or predisseminated MS. The high prevalence of free and/or bound anti-MBP in the CSF of MS patients and the rare and unpredictable occurrence in the CSF of non-MS patients suggest that autoimmunity to MBP may be operative in the demyelination of MS. Molecular clones of anti-MBP with specificity towards variable surface or cryptic MBP epitopes in vivo may determine whether or not they are involved in the demyelinating process, and this variability may also be present within the MS population. Potential mechanisms of anti-MBP-mediated demyelination in MS patients are discussed.