The chemokine CXCL13 in cerebrospinal fluid in children with Lyme neuroborreliosis

Analysis of changes in the chemokine CXC ligand 13 in serum and cerebrospinal fluid of patients with neuromyelitis optica

To determine correlation between the Extended Disability Status Scale(EDSS) grade and the progression of neuromyelitis optica(NMO) patients' levels of the chemokine CXC ligand 13 (CXCL13) in their serum and cerebrospinal fluid. This research included forty-one patients diagnosed with neuromyelitis optica(NMO) and forty-three patients diagnosed with multiple sclerosis(MS). The control group consisted of forty-three non-inflammatory neurological disease(NND) patients. The patients' serum and cerebrospinal fluid CXCL13 levels were measured. Patients in NMO group and MS group had serum and cerebrospinal fluid with CXCL13 levels that were substantially greater than those in the NND group. When comparing the CXCL13 levels of blood and cerebrospinal fluid between patients in the EDSS ≥ 3.5 group and the EDSS<3.5 group, with the EDSS ≥ 3.5 group's CXCL13 levels being greater(P<0.05). There was a positive correlation between the serum CXCL13 and the EDSS grades of both the NMO and MS groups(r = 0.884, P < 0.001); The cerebrospinal fluid CXCL13 of the NMO and MS groups showed a positive correlation with their EDSS grades(r = 0.681, P < 0.001). EDSS scores of NMO patients were positively correlated with their serum BLC-1 (r = 0.896, P < 0.001); EDSS scores of NMO patients were positively correlated with their cerebrospinal fluid BLC-1 (r = 0.678, P < 0.001).EDSS scores of MS patients were positively correlated with their serum BLC-1 (r = 0.852, P < 0.001); EDSS scores of MS patients were positively correlated with their cerebrospinal fluid BLC-1 (r = 0.613, P < 0.001). Serum and cerebrospinal fluid levels of CXCL13 may serve as an important biomarker for the presumptive assessment of the degree of disability in NMO and MS disease, providing a basis for the treatment and control of the disease.

CXCL13 in Cerebrospinal Fluid: Clinical Value in a Large Cross-Sectional Study

C-X-C-motif chemokine ligand 13 (CXCL13) in cerebrospinal fluid (CSF) is increasingly used in clinical routines, although its diagnostic specificity and divergent cut-off values have been defined so far mainly for neuroborreliosis. Our aim was to evaluate the value of CSF-CXCL13 as a diagnostic and treatment response marker and its role as an activity marker in a larger disease spectrum, including neuroborreliosis and other neuroinflammatory and malignant CNS-disorders. Patients who received a diagnostic lumbar puncture (LP) (n = 1234) between July 2009 and January 2023 were included in our retrospective cross-sectional study. The diagnostic performance of CSF-CXCL13 for acute neuroborreliosis was highest at a cut-off of 428.92 pg/mL (sensitivity: 92.1%; specificity: 96.5%). In addition, CXCL13 levels in CSF were significantly elevated in multiple sclerosis with clinical (p = 0.001) and radiographic disease activity (p < 0.001). The clinical utility of CSF-CXCL13 appears to be multifaceted. CSF-CXCL13 is significantly elevated in patients with neuroborreliosis and shows a rapid and sharp decline with antibiotic therapy, but it is not specific for this disease and is also highly elevated in less common subacute neuroinfectious diseases, such as neurosyphilis and cryptococcal meningitis or in primary/secondary B-cell lymphoma.

Cerebrospinal fluid CXCL13 in non-borrelial central nervous system infections: contribution of CXCL13 to the differential diagnosis

BACKGROUND

The chemokine CXCL13 in cerebrospinal fluid (CSF) is used as a diagnostic marker of Lyme neuroborreliosis (LNB). However, the elevated levels in other non-borrelial CNS infections and the lack of a clearly defined cut-off value are limitations of the test.

METHODS

In our prospective study, we evaluated CSF CXCL13 levels in patients with LNB (47 patients), tick-borne encephalitis (TBE; 46 patients), enteroviral CNS infections (EV; 45 patients), herpetic CNS infections (HV; 23 patients), neurosyphilis (NS; 11 patients) and controls (46 patients). The correlation of CXCL13 with CSF mononuclears was determined in all groups.

RESULTS

Median CXCL13 was significantly higher in LNB group; however, the cut-off value of 162 pg/mL was also exceeded in 22% of TBE patients, 2% EV patients, 44% HV patients and in 55% patients with NS. Sensitivity and specificity were 0.83 and 0.78, respectively, with a Youden index of 0.62. CXCL13 was significantly correlated with CSF mononuclears (p = .0024), but the type of infectious agent had a greater influence on CXCL13 levels.

CONCLUSIONS

Increased CXCL13 levels are useful for LNB diagnostics, but other non-purulent CNS infections causes should be considered if intrathecal synthesis of borrelia specific antibodies is not confirmed or clinical manifestations are atypical.

Clinical manifestations of Lyme neuroborreliosis in children: a review

Lyme neuroborreliosis (LNB) is a manifestation of Lyme disease involving the central and peripheral nervous system. It is caused by the spirochete Borrelia burgdorferi, transmitted by tick bites to a human host. Clinical signs of LNB develop after the dissemination of the pathogen to the nervous system. The infection occurs in children and adults, but the clinical manifestations differ. In adults, painful meningoradicultis is the most common manifestation of LNB, while children often present with facial nerve palsy and/or subacute meningitis. Subacute headache can be the only manifestation of LNB in children, especially during the summer months in Lyme disease-endemic regions. Non-specific symptoms, such as loss of appetite, fatigue or mood changes, may also occur, especially in young children. A high level of suspicion and early recognition of the various clinical manifestations presented by children with LNB is essential to minimize delay in diagnosis and optimize management. This review provides an overview of the spectrum of clinical manifestations, and discusses diagnosis, antibiotic treatment, and clinical outcome of LNB in children.

Lyme neuroborreliosis with antibodies in cerebrospinal fluid but not in serum

BACKGROUND AND PURPOSE

To diagnose Lyme neuroborreliosis (LNB), cerebrospinal fluid (CSF) is tested for pleocytosis and intrathecal antibody production. The Dutch guideline for Lyme borreliosis indicates a lumbar puncture in the case of positive Borrelia serology or a strong clinical suspicion of LNB. This suggests that LNB might be underdiagnosed in patients with negative Borrelia serology and/or a minor clinical suspicion. The objective was to assess how often negative Borrelia serology occurs in the case of LNB.

METHOD

A retrospective study was performed among patients with LNB visiting Gelre Hospitals between January 2007 and December 2020. Electronic medical records of patients with pleocytosis were reviewed to identify patients with LNB. Data were collected from medical records.

RESULTS

Included were 127 patients with LNB, 58 of whom were children. In 67 patients Borrelia antibodies were present in both serum and CSF. In 53 of 67 patients there was intrathecal antibody production. In 28 patients there was intrathecal antibody production but serum antibodies were absent. Of patients with positive serology 77% had antibodies in CSF versus 83% of patients with negative serology (p = 0.435). Of patients with positive serology 61% had intrathecal antibody production versus 78% of patients with negative serology (p = 0.073).

CONCLUSIONS

Twenty-eight LNB patients had intrathecal antibody production but no antibodies in serum. In this specific patient population, positive serum serology was not associated with antibodies in CSF nor with intrathecal antibody production. In Lyme endemic areas, in patients with symptoms suggestive for LNB, there is a need to lower the threshold for a lumbar puncture.

Lyme Neuroborreliosis with Intracranial Hypertension and Erythema Multiforme: A Rare Presentation

A 9-year-old previously healthy boy presented with high-grade intermittent fever, severe headache associated with neck stiffness for 5 days, rash over trunk and extremities for 4 days, vomiting for 3 days and diplopia for 2 days. There was no history of seizures, abnormal body movements, altered sensorium or focal deficits. On examination, he had maculopapular erythematous rashes over the trunk and extremities and erythema multiforme. He had bilateral abducens nerve palsy and the rest of the cranial nerve, sensory and motor examination was normal. He had neck stiffness and positive Kernig's sign. Fundus examination showed grade 4 papilledema. Cerebrospinal fluid workup revealed elevated opening pressure, lymphocytic pleocytosis, normal protein and glucose levels. Neuroimaging showed features suggestive of intracranial hypertension. Borrelia IgM and IgG antibodies came positive. The uniqueness of our case lies with two rare presenting manifestations of Lyme neuroborreliosis in the same child.

CXCL13 in laboratory diagnosis of Lyme neuroborreliosis-the performance of the recomBead and ReaScan CXCL13 assays in human cerebrospinal fluid samples

The chemokine CXCL13 is used as complement to serology in the diagnostics of Lyme neuroborreliosis (LNB). We evaluated and compared the semi-quantitative, cassette-based ReaScan CXCL13 assay with the quantitative recomBead CXCL13 assay using a collection of 209 cerebrospinal fluid samples. The categorical agreement between results interpreted as negative, grey zone, and positive by the two methods was 87%. The diagnostic sensitivity was higher using the recomBead assay, whereas specificity was higher using ReaScan. Few manual steps, and a short turn-around time with no batching of samples makes the ReaScan CXCL13 assay an attractive complement to serology in the diagnostics of LNB.

The Usefulness of Two CXCL13 Assays on Cerebrospinal Fluid for the Diagnosis of Lyme Neuroborreliosis: a Retrospective Study in a Routine Clinical Setting

Recent studies have shown elevated levels of the B-cell chemokine (C-X-C motif) ligand 13 (CXCL13) in the cerebrospinal fluid (CSF) of patients with early Lyme neuroborreliosis (LNB). In this retrospective study, we evaluated the diagnostic performance of the Quantikine CXCL13 enzyme-linked immunosorbent assay (ELISA) (R&D Systems, Inc., MN, USA) and the recomBead CXCL13 assay (Mikrogen, Neuried, Germany) for the detection of CXCL13 in CSF. All consecutive patients from whom a CSF and a serum sample had been collected between August 2013 and June 2016 were eligible for inclusion. Patients suspected of LNB were classified as definite, possible, or non-LNB according to the guidelines of the European Federation of Neurological Societies (EFNS). Due to the limited number of LNB patients in the predefined study period, additional LNB patients were included from outside this period. In total, 156 patients (150 consecutive patients and 6 additional LNB patients) were included. Seven (4.5%) were classified as definite, eight (5.1%) as possible, and 141 (90.4%) as non-LNB patients. Receiver operating characteristic (ROC) curve analysis comparing definite-LNB patients with non-LNB patients showed a cutoff value of 85.9 pg/ml for the Quantikine CXCL13 ELISA and 252.2 pg/ml for the recomBead CXCL13 assay. The corresponding sensitivity was 100% (95% confidence interval [CI], 100% to 100%) for both, and the corresponding specificities were 98.6% (95% CI, 96.5% to 100%) for the CXCL13 ELISA and 97.2% (95% CI, 93.6% to 100%) for the recomBead CXCL13 assay. This study showed that CXCL13 in CSF can be of additional value for the diagnosis of LNB.

Lyme Neuroborreliosis in Children

Lyme neuroborreliosis (LNB) is an infectious disease, developing after a tick bite and the dissemination of Borrelia burgdorferi sensu lato spirochetes reach the nervous system. The infection occurs in children and adults but with different clinical courses. Adults complain of radicular pain and paresis, while among the pediatric population, the most common manifestations of LNB are facial nerve palsy and/or subacute meningitis. Moreover, atypical symptoms, such as fatigue, loss of appetite, or mood changes, may also occur. The awareness of the various clinical features existence presented by children with LNB suspicion remains to be of the greatest importance to diagnose and manage the disease.

Lyme neuroborreliosis in Swedish children-PCR as a complementary diagnostic method for detection of Borrelia burgdorferi sensu lato in cerebrospinal fluid

The aim of this study was to evaluate polymerase chain reaction (PCR) as a diagnostic method for the detection of Borrelia burgdorferi s.l. in CSF of Swedish children with LNB. This study was performed retrospectively on CSF and serum samples collected from children evaluated for LNB (n = 233) and controls with other specific neurological disorders (n = 59) in a Swedish Lyme endemic area. For anti-Borrelia antibody index, the IDEIA Lyme Neuroborreliosis kit (Oxoid) was used. Two in-house real-time PCR assays targeting the 16S rRNA gene were evaluated (TaqMan® and LUX™). Among patients classified as LNB cases (n = 102), five children (5%) were Borrelia PCR-positive in CSF with the TaqMan® assay. In the Non-LNB group (n = 131), one patient was Borrelia PCR positive with the TaqMan® assay. Among controls (n = 59), all CSF samples were PCR negative. When amplifying and sequencing ospA, we found B. garinii (n = 2), B. afzelii (n = 2), B. bavariensis (n = 1), and one untypable (n = 1). With the LUX™ technology, all CSF samples were PCR negative. The TaqMan® assay could detect only few cases (n = 6) of B. burgdorferi s.l. in CSF among children with LNB and the sensitivity was very low (5%). However, using larger CSF volumes and centrifugation of samples, the PCR technique could still be useful as a complementary diagnostic method when evaluating LNB. Furthermore, detection of spirochete DNA in clinical matrices, including CSF, is the method of choice for studying epidemiological aspects of LNB, a tick-borne emerging disease.

Sensitivity and specificity of cerebrospinal fluid CXCL13 for diagnosing Lyme neuroborreliosis - a study on 1410 patients and review of the literature

INTRODUCTION

The B-cell chemoattractant CXCL13 has been suggested as a cerebrospinal fluid (CSF) biomarker for Lyme neuroborreliosis (LNB). Our aim was to substantiate the value of CXCL13 in a large unselected cohort and determine a practical cut-off value to diagnose LNB.

METHODS

We retrospectively studied clinical and CSF data of consecutive patients who underwent CSF CXCL13 testing over a period of three years (February 2015 to January 2018) at our academic teaching hospital. Patients were classified into 12 groups according to their final diagnosis. To diagnose LNB (definite or probable/possible), definitions of the respective guideline of the German Neurological Society were applied.

RESULTS

Of 1410 patients, 29 were diagnosed with definite LNB and 9 with probable/possible LNB. Median CXCL13 levels were highly elevated in both LNB groups (554 pg/mL and 649 pg/mL, respectively) and the group with bacterial/fungal CNS infections (410 pg/mL; n = 6), while all other groups had markedly lower median CXCL13 levels (p < .001). For definite LNB, the best CXCL13 test cut-off was 55.5 pg/mL with a sensitivity of 96.6% (95% confidence interval, CI, 80.4%-99.8%) and a specificity of 94.9% (95% CI 93.5%-95.9%). All patients with LNB showed clinical improvement after antibiotic treatment.

CONCLUSION

In this large monocentric cohort, CSF CXCL13 was found to be a highly sensitive and useful marker for LNB. In conditions with low index of suspicion for LNB, CXCL13 testing may be unwarranted. A review of the literature on the sensitivity and specificity of CSF CXCL13 in the differential of LNB is provided.

The potential for CXCL13 in CSF as a differential diagnostic tool in central nervous system infection

Introduction: Central nervous system (CNS) infections can be life-threatening and are often associated with disabling sequelae. One important factor in most CNS infections is a timely pathogen-specific treatment. The diagnostic methods available, however, do not always reach a satisfying sensitivity and specificity. In these cases, there is need for additional diagnostic biomarkers. Chemokines represent potential candidates as biomarkers, since they are an important pillar of the host immune response. The aim of this review is to discuss the diagnostic potential of cerebrospinal fluid (CSF) CXCL13 in patients with CNS infections. Areas covered: Data were obtained from a literature search in PubMed up to October 2019. This review focusses on articles on the potential of CXCL13 as a diagnostic tool. The majority of identified studies aimed to characterize its role in two diseases, namely Lyme neuroborreliosis and neurosyphilis. Expert opinion: CSF CXCL13 has a significant potential as a diagnostic and monitoring add-on marker in Lyme neuroborreliosis. Differences in study design, control groups and clinical parameters between studies, however, affect sensitivity, specificity and cutoff values, underlining the need of further studies to address these issues and pave the way for a generalized clinical practice.

Chemokine Ligand 13 (CXCL13) in Neuroborreliosis and Neurosyphilis as Selected Spirochetal Neurological Diseases: A Review of Its Diagnostic Significance

Neuroborreliosis (NB) and neurosyphilis (NS) are abnormal conditions caused by spirochetal bacteria which affect the nervous system. Diagnosis of neuroborreliosis and neurosyphilis is determined by clinical examination of visible symptoms, serum and cerebrospinal fluid (CSF) analysis, and serological detection of antibodies against Borrelia burgdorferi sensu lato and Treponema pallidum, respectively. Establishing a diagnosis may sometimes pose a number of diagnostic difficulties. A potential role of chemokine ligand 13 (CXCL13) as an accurate diagnostic biomarker of intrathecal inflammation has been suggested. In this review, we focused on changes in serum and cerebrospinal fluid concentration of chemokine ligand 13 in selected spirochetal neurological diseases neuroborreliosis and neurosyphilis reported in the available literature. We performed an extensive search of the literature relevant to our investigation via the MEDLINE/PubMed database. It has been proven that CXCL13 determination can provide rapid information regarding central nervous system inflammation in patients with selected spirochetosis. We described that neuroborreliosis and neurosyphilis are associated with an elevated CXCL13 concentration, mainly in the cerebrospinal fluid. Moreover, literature data suggest that CXCL13 determination is the most interesting additional marker for diagnosis and monitoring of neuroborreliosis and neurosyphilis thanks to its high sensitivity. Based on these published findings, we suggest that CXCL13 has high diagnostic utility and may be applied in laboratory diagnostics as a potential diagnostic marker in human spirochetal neurologic diseases.

Specificity and Diagnostic Utility of Cerebrospinal Fluid CXCL13 in Lyme Neuroborreliosis

Background

Demonstration of intrathecal production of Borrelia-specific antibodies (ITAb) is considered the most specific diagnostic marker of Lyme neuroborreliosis (LNB). Limitations include delayed detectability in early infection and continued presence long after successful treatment. Markers of active inflammation—increased cerebrospinal fluid (CSF) leukocytes, protein, and CXCL13—provide nonspecific markers of active infection. To assess the utility of CSF CXCL13, we measured its concentration in 132 patients with a broad spectrum of neuroinflammatory disorders, including LNB.

Methods

CSF CXCL13 was measured by immunoassay. Spearman rank correlation test was performed to explore its relationship to conventional markers of neuroinflammation and Borrelia-specific ITAb production.

Results

In non-LNB neuroinflammatory disorders, CSF CXCL13 elevation correlated with CSF immunoglobulin G (IgG) synthesis and leukocyte count. In LNB, CXCL13 concentration was far greater than expected from overall CSF IgG synthesis, and correlated with Borrelia-specific ITAb synthesis. Median CSF CXCL13 concentration in ITAb-positive LNB patients was &gt; 500 times greater than in any other group.

Conclusions

Intrathecal CXCL13 and IgG production are closely interrelated. CXCL13 is disproportionately increased in “definite LNB,” defined as having demonstrable Borrelia-specific ITAb, but not “probable LNB,” without ITAb. This disproportionate increase may help identify patients with very early infection or those with active vs treated LNB, or may help to differentiate ITAb-defined active LNB from other neuroinflammatory disorders. However, its reported specificity is closely related to the diagnostic requirement for ITAb. It may add little specificity to the demonstration of a pleocytosis or increased overall or specific IgG production in the CSF.

The predictive value of CXCL13 in suspected Lyme neuroborreliosis: a retrospective cross-sectional study

The role of CXCL13 as a marker of Lyme neuroborreliosis (LNB) is under investigation, and CXCL13 is not part of routine diagnostics in suspicion of LNB. Our aim was to find the optimal cut-off value of CXCL13 for LNB in a Danish population and to investigate the role of CXCL13 both in early LNB and as a discriminatory marker between LNB and other neuroinflammatory disorders. We conducted a retrospective cross-sectional study including all patients with a cerebrospinal CXCL13 test performed at the Department of Clinical Immunology, Odense University Hospital, Denmark, between 1 January 2015 and 31 December 2018. We included 619 patients, of which 51 had definite LNB, 14 patients had possible LNB with neurological symptoms suggestive of LNB and pleocytosis but no intrathecal Borrelia antibodies, eight patients had prior LNB and 546 had no LNB. With an optimal CXCL13 cut-off of 49 ng/L we found a sensitivity of 100% and specificity of 94% (AUC 0.988, 95% CI 0.980-0.996) when patients treated with antibiotics prior to lumbar puncture were excluded (n = 130). All patients with possible LNB had a CXCL13 value above the cut-off value; 18/546 patients (3.3%) without LNB had a CXCL13 value ≥ 50 ng/L. While CXCL13 cannot be used as a stand-alone test, it can be used as a reliable additional marker in treatment-naive patients suspected of LNB. CXCL13 can be used to monitor treatment response in LNB patients.

The Cerebrospinal Fluid Interleukin-6/Interleukin-10 Ratio Differentiates Pediatric Tick-borne Infections

BACKGROUND

Borrelia burgdorferi and tick-borne encephalitis (TBE) virus are 2 types of tick-borne pathogens that can cause central nervous system infection. Routine diagnostics have so far included analysis of cerebrospinal fluid (CSF) cell numbers, CSF serology for Borrelia burgdorferi and serum serology for TBE virus. However, early diagnosis may be difficult based on antibody detection which takes time to analyze, and with the possibility of false negative results, thus delaying treatment. Cytokine analyses are becoming increasingly available in clinical routine care and may offer important information.

METHODS

Fifteen cytokines and chemokines were measured in the CSF from the diagnostic lumbar puncture of 37 children with TBE, 34 children with neuroborreliosis and 19 children without evidence of central nervous system infection, using Luminex technology.

RESULTS

Significantly higher levels of proinflammatory interleukin-6 were detected in the samples from TBE-infected children, when compared with neuroborreliosis or controls. In comparison, children with neuroborreliosis had significantly higher levels of interleukin-7, interleukin-8, interleukin-10, and interleukin-13 when compared with TBE infected or controls. Furthermore, the ratio between interleukin-6 and interleukin-10 was significantly different between the 2 types of tick-borne infections.

CONCLUSIONS

The interleukin-6/interleukin-10 ratio can be used as a rapid diagnostic cue upon suspected tick-borne infection, enabling fast and correct treatment. Also, in serology-negative results, such information may strengthen a clinical suspicion.

Cerebrospinal Fluid Pleocytosis and Elevated C-X-C Motif Chemokine Ligand 13 Value Predict Lyme Borreliosis in Children With Facial Palsy

BACKGROUND

Lyme borreliosis (LB) is a common cause of acute facial palsy in children living in endemic areas for Borrelia burgdorferi. The need for lumbar puncture in diagnostics of LB in children with facial palsy has been questioned. Our aim was to evaluate the prevalence of LB and the diagnostic value of a cerebrospinal fluid (CSF) sample among children with an acute facial palsy.

METHODS

We collected medical records and laboratory data of children and adolescents 0-16 years of age (n = 94) diagnosed with facial palsy between 2002 and 2016 in the Turku University Hospital. A positive B. burgdorferi serology in serum or CSF or a positive B. burgdorferi polymerase chain reaction in CSF were considered as signs of definite LB. C-X-C motif chemokine ligand 13 (CXCL13) values were measured in CSF samples from 28 children during 2014-2016.

RESULTS

Lumbar puncture was performed on 84 of 94 children with facial palsy. LB was confirmed in 29 of 42 children with, and in 4 of 42 without, pleocytosis. The sensitivity and specificity of pleocytosis to predict LB were 88% (95% confidence interval, 78%-98%) and 75% (62%-88%), respectively, and the positive and negative predictive values were 69% (55%-83%) and 90% (81%-99%), respectively. An increased CSF CXCL13 value had 67% (51%-83%) sensitivity and 100% specificity for LB.

CONCLUSIONS

Because serum serology can be negative at presentation, lumbar puncture is a valuable tool when diagnosing LB among children with facial palsy. Pleocytosis and increased protein and CXCL13 values in the CSF suggest LB as the cause of facial palsy.

The roles of chemokine (C-X-C motif) ligand 13 in spinal cord ischemia-reperfusion injury in rats

Spinal cord ischemia-reperfusion injury (SCII) remains an unresolved complication and its underlying mechanism has not been fully elucidated. In this study, we studied the role of chemokine (C-X-C motif) ligand 13 (CXCL13) in a rat model of SCII. We examined the time course and cellular distribution of CXCL13 protein in rats after SCII. The effects of siRNA targeting CXCL13 or C-X-C chemokine receptor type 5 (CXCR5) in SCII were also investigated. Neurological function, histological assessment, and disruption of the blood-spinal cord barrier (BSCB) were evaluated. The expression levels of CXCL13, CXCR5, phosphorylated extracellular signal-regulated kinase (p-ERK), caspase-3, interleukin 6 (IL-6), TNF-α, and IL-1β were determined. We found that SCII resulted in impaired hind limb function and increased the expression of CXCL13. In addition, CXCL13 expression demonstrated the most pronounced effect at 24 h after SCII. We reveal that CXCL13 protein was co-expressed with the mature neuron marker NeuN and the microglial marker IBA-1 in spinal cord tissues of model rats. SCII also increased the expression of CXCR5, p-ERK, caspase-3, IL-6, TNF-α, and IL-1β at 24 h after SCII. Pre-treatment with CXCL13 siRNA protected the rats against SCII and decreased the expression of signalling pathway proteins and proinflammatory cytokines mentioned above. CXCR5 siRNA also showed similar protective effects. These findings indicate that CXCL13 is involved in SCII. The CXCL13/CXCR5 axis promotes the development of SCII, possibly via ERK-mediated pathways. Targeting the mechanism of CXCL13 involved in the development of SCII might be a potential approach for the treatment of this condition.

The B-lymphocyte chemokine CXCL13 in the cerebrospinal fluid of children with Lyme neuroborreliosis: associations with clinical and laboratory variables

Background: The B-lymphocyte chemokine CXCL13 is increasingly considered as a useful early phase diagnostic marker of Lyme neuroborreliosis (LNB). However, the large variation in level of CXCL13 in the cerebrospinal fluid (CSF) observed in LNB patients is still unexplained. We aimed to identify factors associated with the level of CXCL13 in children with LNB, possibly improving the interpretation of CXCL13 as a diagnostic marker of LNB. Methods: Children with confirmed and probable LNB were included in a prospective study on CXCL13 in CSF as a diagnostic marker of LNB. The variables age, sex, facial nerve palsy, generalized inflammation symptoms (fever, headache, neck-stiffness and/or fatigue), duration of symptoms, Borrelia antibodies in CSF, Borrelia antibody index (AI), CSF white blood cells (WBC), CSF protein and detection of the genospecies Borrelia garinii by PCR were included in simple and multivariable regression analyses to study the associations with the CXCL13 level. Results: We included 53 children with confirmed and 17 children with probable LNB. CXCL13 levels in CSF were positively associated with WBC, protein and Borrelia antibodies in CSF in both simple and multivariable analyses. We did not find any associations between CXCL13 and age, sex, clinical symptoms, duration of symptoms, AI or the detection of Borrelia garinii. Conclusions: High levels of CSF CXCL13 are present in the early phase of LNB and correlate with the level of CSF WBC and protein. Our results indicate that CSF CXCL13 in children evaluated for LNB can be interpreted independently of clinical features or duration of symptoms.

Collection and Analyses of Cerebrospinal Fluid for Pediatric Translational Research

Cerebrospinal fluid sample collection and analysis is imperative to better elucidate central nervous system injury and disease in children. Sample collection methods are varied and carry with them certain ethical and biologic considerations, complications, and contraindications. Establishing best practices for sample collection, processing, storage, and transport will ensure optimal sample quality. Cerebrospinal fluid samples can be affected by a number of factors including subject age, sampling method, sampling location, volume extracted, fraction, blood contamination, storage methods, and freeze-thaw cycles. Indicators of sample quality can be assessed by matrix-associated laser desorption/ionization time-of-flight mass spectrometry and include cystatin C fragments, oxidized proteins, prostaglandin D synthase, and evidence of blood contamination. Precise documentation of sample collection processes and the establishment of meticulous handling procedures are essential for the creation of clinically relevant biospecimen repositories. In this review we discuss the ethical considerations and best practices for cerebrospinal fluid collection, as well as the influence of preanalytical factors on cerebrospinal fluid analyses. Cerebrospinal fluid biomarkers in highly researched pediatric diseases or disorders are discussed.