The chemokine CXCL13 is elevated in the cerebrospinal fluid of patients with neurosyphilis.

BACKGROUND: The chemokine CXCL13 has been discussed as a diagnostic parameter with high specificity for Lyme neuroborreliosis (LNB) and as a marker of disease activity. Neurosyphilis and LNB share similar characteristics. We investigated retrospectively CXCL13 levels in the cerebrospinal fluid (CSF) of patients with neurosyphilis at initial diagnosis and during treatment. RESULTS: Five patients with neurosyphilis were identified retrospectively using an electronic database in a tertiary care hospital from 2005 to 2012. CXCL13 levels were measured using an ELISA. Five patients with definite LNB and 10 patients with multiple sclerosis (MS) served as controls. Median CXCL13 levels at baseline were 972 pg/mL for neurosyphilis patients, 8,000 pg/mL for LNB patients, and 7.8 pg/mL for MS patients. Patients with LNB and neurosyphilis showed significantly higher CXCL13 levels in their CSF compared to MS patients (p < 0.05, p < 0.001, respectively). CXCL13 levels in the CSF declined during treatment. CONCLUSION: CXCL13 levels in the CSF of patients with neurosyphilis can be as high as in patients with LNB, exceeding the proposed threshold of 250 pg/mL for the diagnosis of LNB. Patients with encephalitic/myelitic syndromes appear to have especially high levels of CXCL13. Clinicians should be aware that high levels of CXCL13 are not found exclusively in LNB but also in other infectious diseases of the CNS.

CSF proteome analysis in clinically isolated syndrome (CIS): candidate markers for conversion to definite multiple sclerosis.

Cerebrospinal fluid (CSF) is a promising source of biomarkers in clinically isolated syndrome (CIS), which frequently presents as a first episode of multiple sclerosis (MS). Using the two-dimensional difference in gel electrophoresis (2-D DIGE), we compared CSF samples from patients with CIS that remained CIS (CIS-CIS, n=8) over a follow-up time of 2 years and from patients with CIS that developed definite MS of the relapsing-remitting subtype (CIS-RRMS, n=8) over the same period. Protein spots that showed significant differences between patients and controls were selected for further analysis by MALDI-TOF mass spectrometry. For validation of identified spots ELISA experiments were performed. We identified one protein that was upregulated in CIS-RRMS (serin peptidase inhibitor) and eight proteins (alpha-1-B-glycoprotein, Fetuin-A, apolipoprotein A4, haptoglobin, human Zinc-alpha-2-glycoprotein (ZAG), Retinol-binding protein, superoxid dismutase 1, transferrin) that were down-regulated in CIS-RRMS vs. CIS-CIS. For Fetuin-A, our findings could be confirmed by ELISA. The pathophysiological role as well as clinical relevance of these candidate proteins in CIS remains to be further clarified by future studies.

Cerebrospinal fluid proteome profile in multiple sclerosis.

Cerebrospinal fluid (CSF) proteins may provide important information about the pathomechanisms present in multiple sclerosis (MS). Although diagnostic criteria for early MS are available, there is still a need for biomarkers, predicting disease subtype and progression to improve individually tailored treatment. Using the two-dimensional difference gel electrophoresis (2-D-DIGE) technology for comparative analysis, we compared CSF samples from patients with MS of the relapse-remitting type (RRMS, n = 12) and from patients with clinically isolated syndrome (CIS, n = 12) suggestive of a first demyelinating attack with neurologically normal controls. Protein spots that showed more than two-fold difference between patients and controls were selected for further analysis with MALDI-TOF mass spectrometry. Immunoblot analysis was performed to confirm the validity of individual candidate proteins. In RRMS, we identified 1 up-regulated and 10 down-regulated proteins. In CIS, 2 up-regulated and 11 down-regulated proteins were identified. One of these proteins (Apolipoprotein A1) was confirmed by immunoblot. Though the pathophysiological role of these proteins still remains to be elucidated in detail and further validation is needed, these findings may have a relevant impact on the identification of disease-specific markers.

Proteome analysis of cerebrospinal fluid in Guillain-Barré syndrome (GBS).

We used two-dimensional difference in-gel electrophoresis (2-D-DIGE) for proteome analysis of cerebrospinal fluid (CSF) in Guillain-Barré syndrome (GBS). Spots showing >2-fold difference between GBS and controls were analysed using MALDI-TOF mass spectrometry. Proteins that were up-regulated in GBS included haptoglobin, serine/threonine kinase 10, alpha-1-antitrypsin, SNC73, alpha II spectrin, IgG kappa chain and cathepsin D preprotein, while transferrin, caldesmon, GALT, human heat shock protein 70, amyloidosis patient HL-heart-peptide 127aa and transthyretin were down-regulated. Some of these proteins are reported in CSF of GBS for the first time. Accordingly, the 2-D-DIGE technology may be useful to identify disease-specific proteins in patients with GBS.

Dopaminergic neurotoxicity of homocysteine and its derivatives in primary mesencephalic cultures.

Levodopa and dopamine are metabolized to 3-O-methyldopa and 3-methoxytyramine, respectively, by the enzyme catechol-O-methyltransferase (COMT) leading to the production of the demethylated cofactor S-adenosylhomo-cysteine (SAH) and subsequently homocysteine (HC). Indeed, treatment of Parkinson's disease (PD) patients with levodopa leads to increased HC blood levels. Therefore, HC is discussed to be involved in the pathogenesis of PD as well as in enhanced progression of PD in patients treated with levodopa. Here we investigated the toxicity of HC and its derivatives SAH, homocysteic acid (HCA) and cysteic acid (CA) on tyrosine hydroxylase (TH)-positive neurons in primary mesencephalic cultures from rat in vitro. Furthermore, we evaluated the toxicity of HC on cultures stressed with the dopaminergic neurotoxin 1-methyl-4-phenylpyridinium (MPP+). Incubation with HC or HCA did not result in significant effects on TH-positive neuron survival with concentrations up to 1 mM, but led to morphological changes of TH-positive cells with significantly fewer and shorter neurites at concentrations of > or = 100 microM after 48 h. In contrast, SAH and CA were toxic at concentrations of >100 microM after 48h. Furthermore, MPP+ showed strong toxicity towards TH-positive cells after 48 h (half-maximal toxic concentration: 20 microM), whereas co-incubation with HC for 24 or 48 h did not further alter TH-positive cell survival. Taken together, our results do not demonstrate relevant dopaminergic toxicity of HC in vitro, and therefore HC is most likely not involved in the pathogenesis of PD or in accelerating the progression of PD by levodopa.

Mycobacterium bovis Bacille Calmette-Guérin strains secreting listeriolysin of Listeria monocytogenes.

Recombinant (r) Mycobacterium bovis strains were constructed that secrete biologically active listeriolysin (Hly) fusion protein of Listeria monocytogenes. The r-BCG strains pAT261:Hly or pMV306:Hly expressed plasmid multicopies or chromosomal single copies of the hly gene, respectively. Human and murine macrophage-like cell lines were infected with r-BCG pAT261:Hly and pMV306:Hly strains. Interestingly, intracellular persistence of both r-BCG strains was reduced in macrophages as compared with the parental BCG strain. By immunogold labeling Hly was detected in membrane structures and within the phagosomal space of macrophages. In addition, Hly was localized within cytoplasmic vacuoles outside the mycobacteria-containing phagosome of host cells infected with r-BCG pAT261:Hly or r-BCG pMV306:Hly. Hly fusions consistently colocalized with a lysosome-associated membrane glycoprotein, suggesting that membrane-attack conformation of Hly was not altered. Although r-BCG pAT261:Hly and r-BCG pMV306:Hly microorganims apparently did not egress into the cytoplasmic compartment of host cells, they both improved major histocompatibility complex class I presentation of cophagocytosed soluble protein as compared with wild-type BCG microbes. These data suggest that Hly secretion endows BCG with an improved capacity to stimulate CD8 T cells. Because CD8 T cells play a major role in protection against tuberculosis such Hly secreting r-BCG constructs are antituberculosis vaccine candidates.