The definite diagnosis of acute Lyme neuroborreliosis (LNB) requires detection of an increased Borrelia burgdorferi-specific antibody index (AI). The B burgdorferi AI, however, is negative in up to ...20% of patients with early LNB and can remain elevated for years after adequate therapy; both of these factors can make the diagnosis difficult. Recent retrospective studies suggested the chemokine CXCL13 as a potential biomarker for LNB. To evaluate its diagnostic value, we conducted a prospective study.
From March 2008 to August 2009, CSF and serum samples from all patients in whom a B burgdorferi-specific AI was requested (n=692) and CSF analysis revealed CSF pleocytosis (n=192) were included in the study. Because of the low number of patients with untreated LNB, 13 additional retrospectively selected samples of patients with untreated LNB were added. CXCL13 concentrations were measured by ELISA and receiver operating characteristic curves were generated.
CSF CXCL13 was highly elevated in all patients with untreated acute LNB (mean=15,149 pg/mL) compared with that in the patients without LNB (mean=247 pg/mL). At a cutoff of 1,229 pg/mL, the sensitivity of CXCL13 was 94.1%, which is higher than the AI (85.7%). Only 7 patients (5 with a CNS lymphoma and 2 with bacterial meningitis) had a CXCL13 level above the cutoff, resulting in a specificity equal to the AI of 96.1%.
CXCL13 shows high sensitivity and specificity for acute, untreated LNB. This novel marker appears to be helpful in clinically atypical cases and, in particular, in early stages of the disease when the B burgdorferi AI is (still) negative.
The chemokine CXCL13 is known to dictate homing and motility of B cells in lymphoid tissue and has been implicated in the formation of ectopic lymphoid tissue in chronic inflammation. Whether it ...influences B cell trafficking during acute infection, is largely unclear. In previous studies, we showed that (I) CXCL13 levels are markedly increased in the B cell-rich cerebrospinal fluid (CSF) of patients with acute Lyme neuroborreliosis (LNB), and (II) CXCL13 is released by monocytes upon recognition of borrelial outer surface proteins by Toll-like receptor 2. Here, we assessed the role of CXCL13--in comparison to other chemokines--in the recruitment of B cells to the CSF of patients with acute LNB.
Measurement of chemokines was done by ELISA. B cells were isolated from whole blood using magnetic cell separation (MACS). For migration experiments, a modified Boyden chamber assay was used and the migrated B cells were further analysed by FACS. The migration was inhibited either by preincubation of the CSF samples with neutralizing antibodies, heating to 60 degrees C, removal of proteins >3 kDa, or by pre-treatment of the B cells with pertussis toxin. The principal statistical tests used were one-way analysis of variance and Bonferroni test (chemokine measurements) as well as paired Student's t-test (migration experiments).
Measurements of chemokine levels revealed an increase in three of the four known major B cell chemoattractants CXCL13, CCL19 and CXCL12 in LNB CSF. The CXCL13 CSF:serum ratio, as a measure of the chemotactic gradient, was substantially higher than that of CCL19 and CXCL12. Moreover, the chemotactic activity of LNB CSF was reduced up to 56% after preincubation with a neutralizing CXCL13 antibody, while combined preincubation with antibodies against CXCL13, CCL19, and CXCL12 did not lead to further reduction. Since treatment with pertussis toxin, heating to 60 degrees C, and removal of proteins >3 kDa abrogated the chemotactic activity, further not yet identified chemokines seem to be involved in B cell recruitment to LNB CSF.
Combined, our study suggests a key role of CXCL13 in B cell migration to sites of infection as shown here for the CSF of LNB patients.
The chemokine CXCL13 in acute neuroborreliosis Senel, Makbule; Rupprecht, Tobias A; Tumani, Hayrettin ...
Journal of neurology, neurosurgery and psychiatry,
08/2010, Volume:
81, Issue:
8
Journal Article
Peer reviewed
Open access
Recent studies have suggested an important role of the B cell chemoattractant CXCL13 in acute neuroborreliosis (NB). Our aim was to confirm the diagnostic role of CXCL13 and to evaluate its relevance ...as a therapy response and disease activity marker in NB.
CXCL13 was measured in cerebrospinal fluid (CSF) and serum of patients with NB (n=28), systemic borreliosis (SB, n=9), Guillain-Barré syndrome (GBS, n=11), Bell's palsy (BP, n=19), other cranial nerve palsies (CNP, n=5), cephalgia (C, n=20), bacterial CNS infections (B-CNS-I, n=16) and viral CNS infections (V-CNS-I, n=18). For follow-up studies, serial sample pairs were evaluated from 25 patients with NB (n=56), 11 with B-CNS-I (n=25) and 14 with V-CNS-I (n=36).
CSF-CXCL13 was significantly elevated in NB compared with other neurological diseases (p<0.001). Using receiver operating characteristic analysis, 337 ng/g was determined as a cut-off with a sensitivity of 96.4% and a specificity of 96.9%. Of all the parameters investigated, CSF CXCL13 showed the fastest response to antibiotic therapy, decreasing significantly (p=0.008) within 1 week. In untreated patients, CSF CXCL13 was elevated in patients with a short duration of disease. Borrelia burgdorferi antibody index showed no significant (p=0.356) change over follow-up.
The study confirms the relevance of CXCL13 as a diagnostic biomarker of NB and suggests that CSF CXCL13 in NB is linked to duration of disease and could be a marker of disease activity and response to antibiotic therapy.
Using protein expression profiling, the authors identified an upregulation of the chemokine B lymphocyte chemoattractant (BLC) in the CSF of patients with neuroborreliosis but not in patients with ...noninflammatory and various other inflammatory neurologic diseases. This upregulation was confirmed by ELISA, showing increased BLC levels in every neuroborreliosis patient while being undetectable in patients with noninflammatory neurologic diseases. These results point to BLC as a putative additional diagnostic marker for neuroborreliosis.
The utility of cerebrospinal fluid (CSF) CXCL13 for diagnosis of acute Lyme neuroborreliosis (LNB) has been debated and the test is not yet routinely performed. This study's aim was to evaluate its ...overall diagnostic accuracy through meta-analysis.
Electronic searches in PubMed MEDLINE and Web of Science were performed to identify relevant articles published before January 2018. A summary receiver operating characteristic curve and an optimal cut-off were estimated modelling multiple cut-offs. Publication bias was evaluated using a funnel plot and the associated regression test.
A total of 18 studies involving 618 individuals with acute LNB and 2326 individuals with other neurological disorders meeting the eligibility criteria were identified. The pooled sensitivity for CSF CXCL13 was 89% (95% CI 85%–93%) and the pooled specificity was 96% (95% CI 92%–98%), using the identified optimal cut-off value of 162 pg/mL. There was marked heterogeneity between studies, caused by differences in the designs of the study populations and age distribution. The optimal cut-off in the seven studies with a cross-sectional design was 91 pg/mL (sensitivity 96%, 95% CI 92%–98%; specificity 94%, 95% CI 86%–97%) and in the 11 case–control studies it was 164 pg/mL (sensitivity 85%, 95% CI 78%–91%; specificity 95%, 95% CI 90%–98%). CSF CXCL13 values above the optimal cut-off level (determined in this meta-analysis) were also detectable in some other central nervous system disorders, namely neurosyphilis and central nervous system lymphoma.
Our meta-analysis shows that CSF CXCL13 has the potential to become a useful adjunct in the diagnosis of acute LNB.
Human herpesvirus 6 (HHV-6), the causative agent of exanthema subitum in childhood, can also induce meningoencephalitis in immunocompromised individuals. In contrast, HHV-6 encephalitis in ...immunocompetent patients is rare, and the clinical syndrome not well defined. We report a case of meningoencephalitis caused by HHV-6 type B in an otherwise healthy woman.
Recent studies have suggested an important role for the B-cell-attracting chemokine CXCL13 in the B-cell-dominated cerebrospinal fluid (CSF) infiltrate in patients with neuroborreliosis (NB). High ...levels of CXCL13 were present in the CSF of NB patients. It has not been clear, however, whether high CSF CXCL13 titers are specific for NB or are a characteristic of other spirochetal diseases as well. Furthermore, the mechanisms leading to the observed CXCL13 expression have not been identified yet. Here we describe similarly elevated CSF CXCL13 levels in patients with neurosyphilis, while pneumococcal meningitis patient CSF do not have high CXCL13 levels. In parallel, challenge of human monocytes in vitro with two of the spirochetal causative organisms, Borrelia garinii (the Borrelia species most frequently found in NB patients) and Treponema pallidum, but not challenge with pneumococci, induced CXCL13 release. This finding implies that a common spirochetal motif is a CXCL13 inducer. Accordingly, we found that the lipid moiety N-palmitoyl-S-(bispalmitoyloxypropyl)cystein (Pam₃C) (three palmitoyl residues bound to N-terminal cysteine) of the spirochetal lipoproteins is critical for the CXCL13 induction in monocytes. As the Pam₃C motif is known to signal via Toll-like receptor 2 (TLR2) and an anti-TLR2 monoclonal antibody blocked CXCL13 production of human monocytes incubated with B. garinii, this suggests that TLR2 is a major mediator of Borrelia-induced secretion of CXCL13 from human monocytes.
In this study, we analyzed the expression and function of CXCL16 in pneumococcal meningitis. CXCL16 was found to be up-regulated in RAW264.7 macrophages (but not in neutrophils and endothelial cells) ...upon pneumococcal stimulation, in the cerebrospinal fluid of patients, and in brains as well as the cerebrospinal fluid of mice with pneumococcal meningitis. CXCL16 up-regulation in vivo was dependent on Toll-like receptor (TLR) 2/TLR4 and MyD88 signaling. Neutralization of CXCL16 in animals before intracisternal pneumococcal infection (using anti-CXCL16 antibodies) resulted in reduced cerebrospinal fluid pleocytosis. In vitro, murine neutrophils expressed the CXCL16 receptor CXCR6 and showed dose-dependant migration toward a CXCL16 gradient. Thus, this study implicates CXCL16 as an additional neutrophil chemoattractant in cerebrospinal fluid in early pneumococcal meningitis.
This review describes the current knowledge of the pathogenesis of acute Lyme neuroborreliosis (LNB), from invasion to inflammation of the central nervous system. Borrelia burgdorferi (B.b.) enters ...the host through a tick bite on the skin and may disseminate from there to secondary organs, including the central nervous system. To achieve this, B.b. first has to evade the hostile immune system. In a second step, the borrelia have to reach the central nervous system and cross the blood-brain barrier. Once in the cerebrospinal fluid (CSF), the spirochetes elicit an inflammatory response. We describe current knowledge about the infiltration of leukocytes into the CSF in LNB. In the final section, we discuss the mechanisms by which the spirochetal infection leads to the observed neural dysfunction. To conclude, we construct a stringent concept of the pathogenesis of LNB.
In the first part of this review, a summarized description of the typical clinical manifestation as well as less frequent symptoms of early (acute) Lyme Neuroborreliosis (LNB) are presented. In the ...second part, insights into the controversial topic of “Post-Treatment Lyme Disease Syndrome” are given and the quite rare, but clearly defined picture of late (chronic) LNB is described.
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