Cytokines and chemokines profile in encephalitis patients: A meta-analysis

BACKGROUND

Encephalitis is caused by autoimmune or infectious agents marked by brain inflammation. Investigations have reported altered concentrations of the cytokines in encephalitis. This study was conducted to determine the relationship between encephalitis and alterations of cytokine levels in cerebrospinal fluid (CSF) and serum.

METHODS

We found possibly suitable studies by searching PubMed, Embase, Scopus, and Web of Science, systematically from inception to August 2021. 23 articles were included in the meta-analysis. To investigate sources of heterogeneity, subgroup analysis and sensitivity analysis were conducted. The protocol of the study has been registered in PROSPERO with a registration ID of CRD42021289298.

RESULTS

A total of 23 met our eligibility criteria to be included in the meta-analysis. A total of 12 cytokines were included in the meta-analysis of CSF concentration. Moreover, 5 cytokines were also included in the serum/plasma concentration meta-analysis. According to the analyses, patients with encephalitis had higher CSF amounts of IL-6, IL-8, IL-10, CXCL10, and TNF-α than healthy controls. The alteration in the concentration of IL-2, IL-4, IL-17, CCL2, CXCL9, CXCL13, and IFN-γ was not significant. In addition, the serum/plasma levels of the TNF-α were increased in encephalitis patients, but serum/plasma concentration of the IL-6, IL-10, CXCL10, and CXCL13 remained unchanged.

CONCLUSIONS

This meta-analysis provides evidence for higher CSF concentrations of IL-6, IL-8, IL-10, CXCL10, and TNF-α in encephalitis patients compared to controls. The diagnostic and prognostic value of these cytokines and chemokines should be investigated in future studies.

Cytokine/chemokine levels in the CSF and serum of anti-NMDAR encephalitis: A systematic review and meta-analysis

OBJECTIVES

To summarize the cytokine/chemokine levels of anti-N-methyl-Daspartate receptor encephalitis (NMDAR-E) and explore the potential role of these molecules and immune cells in the pathogenic mechanism.

METHODS

The PubMed, Cochrane Library, Embase, and Web of Science databases were searched for various articles that assessed the concentrations of cytokines/chemokines in the unstimulated cerebrospinal fluid (CSF) or serum of patients with NMDAR-E in this systematic review and meta-analysis. The standardized mean difference (SMD) and 95% confidence interval (CI) were calculated by Stata17.0.

RESULTS

A total of 19 articles were included in the systematic review from 260 candidate papers, and cytokine/chemokine levels reported in the CSF/serum were examined in each article. This meta-analysis included 17 eligible studies comprising 579 patients with NMDAR-E, 367 patients with noninflammatory neurological disorders, and 42 healthy controls from China, Spain, South Korea, Australia, Czechia, and Sweden. The results indicated that the levels of different cytokines interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-10, IL-13, IL-1β, IL-12, and IL-17 and chemokine C-X-C motif ligand (CXCL)10 in the CSF were significantly higher in NMDAR-E patients with a large effect size. In addition, B cell activating factor (BAFF), CXCL13, and interferon (IFN)-γ levels in the CSF were higher in NMDAR-E patients with a middle effect size. In contrast, levels of IL-2 and IL-4 in the CSF and CXCL13 and BAFF in the serum did not show a significant difference between cases and controls.

CONCLUSIONS

These analyses showed that the central immune response in NMDAR-E is a process that involves multiple immune cell interactions mediated by cytokines/chemokines, and T cells play an important role in the pathogenesis of immunity.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/PROSPERO/, identifier (CRD42022342485).

Differential chemokine alteration in the variants of primary progressive aphasia-a role for neuroinflammation

BACKGROUND

The primary progressive aphasias (PPA) represent a group of usually sporadic neurodegenerative disorders with three main variants: the nonfluent or agrammatic variant (nfvPPA), the semantic variant (svPPA), and the logopenic variant (lvPPA). They are usually associated with a specific underlying pathology: nfvPPA with a primary tauopathy, svPPA with a TDP-43 proteinopathy, and lvPPA with underlying Alzheimer's disease (AD). Little is known about their cause or pathophysiology, but prior studies in both AD and svPPA have suggested a role for neuroinflammation. In this study, we set out to investigate the role of chemokines across the PPA spectrum, with a primary focus on central changes in cerebrospinal fluid (CSF) METHODS: Thirty-six participants with sporadic PPA (11 svPPA, 13 nfvPPA, and 12 lvPPA) as well as 19 healthy controls were recruited to the study and donated CSF and plasma samples. All patients with lvPPA had a tau/Aβ42 biomarker profile consistent with AD, whilst this was normal in the other PPA groups and controls. We assessed twenty chemokines in CSF and plasma using Proximity Extension Assay technology: CCL2 (MCP-1), CCL3 (MIP-1a), CCL4 (MIP-1β), CCL7 (MCP-3), CCL8 (MCP-2), CCL11 (eotaxin), CCL13 (MCP-4), CCL19, CCL20, CCL23, CCL25, CCL28, CX3CL1 (fractalkine), CXCL1, CXCL5, CXCL6, CXCL8 (IL-8), CXCL9, CXCL10, and CXCL11.

RESULTS

In CSF, CCL19 and CXCL6 were decreased in both svPPA and nfvPPA compared with controls whilst CXCL5 was decreased in the nfvPPA group with a borderline significant decrease in the svPPA group. In contrast, CCL2, CCL3 and CX3CL1 were increased in lvPPA compared with controls and nfvPPA (and greater than svPPA for CX3CL1). CXCL1 was also increased in lvPPA compared with nfvPPA but not the other groups. CX3CL1 was significantly correlated with CSF total tau concentrations in the controls and each of the PPA groups. Fewer significant differences were seen between groups in plasma, although in general, results were in the opposite direction to CSF, i.e. decreased in lvPPA compared with controls (CCL3 and CCL19), and increased in svPPA (CCL8) and nfvPPA (CCL13).

CONCLUSION

Differential alteration of chemokines across the PPA variants is seen in both CSF and plasma. Importantly, these results suggest a role for neuroinflammation in these poorly understood sporadic disorders, and therefore also a potential future therapeutic target.

Selected Biomarkers of Tick-Borne Encephalitis: A Review

Tick-borne encephalitis (TBE) is an acute disease caused by the tick-borne encephalitis virus. Due to the viral nature of the condition, there is no effective causal treatment for full-blown disease. Current and nonspecific TBE treatments only relieve symptoms. Unfortunately, the first phase of TBE is characterized by flu-like symptoms, making diagnosis difficult during this period. The second phase is referred to as the neurological phase as it involves structures in the central nervous system-most commonly the meninges and, in more severe cases, the brain and the spinal cord. Therefore, it is important that early markers of TBE that will guide clinical decision-making and the choice of treatment are established. In this review, we performed an extensive search of literature reports relevant to biomarkers associated with TBE using the MEDLINE/PubMed database. We observed that apart from routinely determined specific immunoglobulins, free light chains may also be useful in the evaluation of intrathecal synthesis in the central nervous system (CNS) during TBEV infection. Moreover, selected metalloproteinases, chemokines, or cytokines appear to play an important role in the pathogenesis of TBE as a consequence of inflammatory reactions and recruitment of white blood cells into the CNS. Furthermore, we reported promising findings on tau protein or Toll-like receptors. It was also observed that some people may be predisposed to TBE. Therefore, to understand the role of selected tick-borne encephalitis biomarkers, we categorized these factors and discussed their potential application in the diagnosis, prognosis, monitoring, or management of TBE.

Correlation between Blood and CSF Compartment Cytokines and Chemokines in Subjects with Cryptococcal Meningitis

BACKGROUND

Though peripheral blood is a crucial sample to study immunology, it is unclear whether the immune environment in the peripheral vasculature correlates with that at the end-organ site of infection. Using cryptococcal meningitis as a model, we investigated the correlation between serum and cerebrospinal fluid biomarkers over time.

METHODS

We analyzed the cerebrospinal fluid and serum of 160 subjects presenting with first episode cryptococcal meningitis for soluble cytokines and chemokines measured by Luminex assay. Specimens were collected at meningitis diagnosis, 1-week, and 2-week post cryptococcal diagnosis. We compared paired samples by Spearman's correlation and the p value was set at <0.01.

RESULTS

Of the 21 analytes tested at baseline, there was no correlation detected between nearly all analytes. A weak negative correlation was found between serum and cerebrospinal fluid levels of interferon-gamma (Rho = -0.214; p = .007) and interleukin-4 (Rho = -0.232; p = .003). There was no correlation at 1-week post cryptococcal diagnosis. However, at 2-week post cryptococcal diagnosis, there was a weak positive correlation of granulocyte-macrophage colony-stimulating factor levels (Rho = 0.25; p = .007) in serum and cerebrospinal fluid. No cytokine or chemokine showed consistent correlation overtime.

CONCLUSION

Based on our analysis of 21 biomarkers, serum and cerebrospinal fluid immune responses do not correlate. There appears to be a distinct immune environment in terms of soluble biomarkers in the vasculature versus end-organ site of infection. While this is a model of HIV-related cryptococcal meningitis, we postulate that assuming the blood compartment is representative of the immune function at the end-organ site of infection may not be appropriate.

Preventive Triple Gene Therapy Reduces the Negative Consequences of Ischemia-Induced Brain Injury after Modelling Stroke in a Rat

Currently, the main fundamental and clinical interest for stroke therapy is focused on developing a neuroprotective treatment of a penumbra region within the therapeutic window. The development of treatments for ischemic stroke in at-risk patients is of particular interest. Preventive gene therapy may significantly reduce the negative consequences of ischemia-induced brain injury. In the present study, we suggest the approach of preventive gene therapy for stroke. Adenoviral vectors carrying genes encoding vascular endothelial growth factor (VEGF), glial cell-derived neurotrophic factor (GDNF) and neural cell adhesion molecule (NCAM) or gene engineered umbilical cord blood mononuclear cells (UCB-MC) overexpressing recombinant VEGF, GDNF, and NCAM were intrathecally injected before distal occlusion of the middle cerebral artery in rats. Post-ischemic brain recovery was investigated 21 days after stroke modelling. Morphometric and immunofluorescent analysis revealed a reduction of infarction volume accompanied with a lower number of apoptotic cells and decreased expression of Hsp70 in the peri-infarct region in gene-treated animals. The lower immunopositive areas for astrocytes and microglial cells markers, higher number of oligodendrocytes and increased expression of synaptic proteins suggest the inhibition of astrogliosis, supporting the corresponding myelination and functional recovery of neurons in animals receiving preventive gene therapy. In this study, for the first time, we provide evidence of the beneficial effects of preventive triple gene therapy by an adenoviral- or UCB-MC-mediated intrathecal simultaneous delivery combination of vegf165, gdnf, and ncam1 on the preservation and recovery of the brain in rats with subsequent modelling of stroke.

Utility of chemokines CCL2, CXCL8, 10 and 13 and interleukin 6 in the pediatric cohort for the recognition of neuroinflammation and in the context of traditional cerebrospinal fluid neuroinflammatory biomarkers

BACKGROUND

The recognition of active inflammation in the central nervous system (CNS) in the absence of infectious agents is challenging. The present study aimed to determine the diagnostic relevance of five selected chemo/cytokines in the recognition of CNS inflammation and in the context of traditional cerebrospinal fluid (CSF) biomarkers (white blood cell [WBC] counts, oligoclonal bands, protein levels, CSF/serum albumin ratios) and clinical diagnoses.

METHODS

C-C and C-X-C motif ligands (CCL2, CXCL8, 10 and 13) and interleukin (IL) 6 levels in the CSF and serum from 37 control and 87 symptomatic children with ten different (mostly noninfectious) inflammatory CNS disorders (16 of which had follow-up samples after recovery) were determined using Luminex multiple bead technology and software. Nonparametric tests were used; p < 0.05 was considered statistically significant. Receiver operating characteristic curves were constructed to analyze controls and 1) all symptomatic samples or 2) symptomatic samples without CSF pleocytosis.

RESULTS

Compared with the control CSF samples, levels of all investigated chemo/cytokines were increased in symptomatic CSF samples, and only IL-6 remained elevated in recovery samples (p ≤ 0.001). CSF CXCL-13 levels (> 10.9 pg/mL) were the best individual discriminatory criterion to differentiate neuroinflammation (specificity/sensitivity: 97/72% and 97/61% for samples without pleocytosis), followed by CSF WBC counts (specificity/sensitivity: 97/62%). The clinical utility of the remaining CSF chemo/cytokine levels was determined in descending order of sensitivities corresponding to thresholds that ensured 97% specificity for neuroinflammation in samples without pleocytosis (pg/mL; sensitivity %): IL-6 (3.8; 34), CXCL8 (32; 26), CXCL10 (317; 24) and CCL2 (387; 10). Different diagnosis-related patterns of CSF chemo/cytokines were observed.

CONCLUSIONS

The increased CSF level of CXCL13 was the marker with the greatest predictive utility for the general recognition of neuroinflammation among all of the individually investigated biomarkers. The potential clinical utility of chemo/cytokines in the differential diagnosis of neuroinflammatory diseases was identified.

Immune Abnormalities in Autism Spectrum Disorder-Could They Hold Promise for Causative Treatment?

Autism spectrum disorders (ASD) are characterized by impairments in language and communication development, social behavior, and the occurrence of stereotypic patterns of behavior and interests. Despite substantial speculation about causes of ASD, its exact etiology remains unknown. Recent studies highlight a link between immune dysfunction and behavioral traits. Various immune anomalies, including humoral and cellular immunity along with abnormalities at the molecular level, have been reported. There is evidence of altered immune function both in cerebrospinal fluid and peripheral blood. Several studies hypothesize a role for neuroinflammation in ASD and are supported by brain tissue and cerebrospinal fluid analysis, as well as evidence of microglial activation. It has been shown that immune abnormalities occur in a substantial number of individuals with ASD. Identifying subgroups with immune system dysregulation and linking specific cellular immunophenotypes to different symptoms would be key to defining a group of patients with immune abnormalities as a major etiology underlying behavioral symptoms. These determinations would provide the opportunity to investigate causative treatments for a defined patient group that may specifically benefit from such an approach. This review summarizes recent insights into immune system dysfunction in individuals with ASD and discusses the potential implications for future therapies.

Disease activity, autoantibodies, and inflammatory molecules in serum and cerebrospinal fluid of patients with Systemic Lupus Erythematosus and Cognitive Dysfunction

Objective

To determine if cognitive dysfunction in patients with systemic lupus erythematosus (SLE) derives from an inflammatory process with continuing disease activity, and increased levels of autoantibodies and inflammatory molecules in serum and cerebrospinal fluid (CSF).

Methods

100 randomly selected patients participating in an inception SLE cohort were studied. At entry into the cohort, a standardized medical history and extensive laboratory tests profile, including autoantibodies were completed. Follow-up occurred every 3–6 months with assessment of lupus characteristics, comorbidities, and treatment. After a mean follow-up of six-years, cross-sectional evaluation of cognitive function was done with standardized tests, and in a subset of patients an extended profile of autoantibodies, cytokines and chemokines was measured in serum and CSF.

Results

At enrollment into the cohort, patients were 26.4±8.2 years of age and lupus duration 5.3±3.7 months. Moderate/severe cognitive dysfunction was diagnosed in 16 patients; in comparison to patients with normal cognitive function, they had lower education 9 vs. 12 years (P = 0.006), higher body mass index 26.7 vs. 24.3 (P = 0.03), positive IgG anticardiolipin antibodies 50% vs 18% (P = 0.009), and a higher median number of concomitant NPSLE syndromes 3 vs. 1, (P = 0.04). The prevalence of cardiovascular-risk factors, other auto-antibodies, lupus activity, treatment, and incidence of critical events did not differ. In serum and CSF, the levels of autoantibodies, cytokines and chemokine were similar, only CCL2 was elevated in CSF [886.1 (374.9–1439.7) vs. 515.8 (3.2–1958.2) pg/mL, P = 0.04].

Conclusion

Scant evidence of inflammation in SLE patients with cognitive dysfunction was observed. Only a higher prevalence of IgG anticardiolipin antibodies in serum and increased levels of CCL2 in CSF were detected.

Expression of interferon-inducible chemokines and sleep/wake changes during early encephalitis in experimental African trypanosomiasis

BACKGROUND

Human African trypanosomiasis or sleeping sickness, caused by the parasite Trypanosoma brucei, leads to neuroinflammation and characteristic sleep/wake alterations. The relationship between the onset of these alterations and the development of neuroinflammation is of high translational relevance, but remains unclear. This study investigates the expression of interferon (IFN)-γ and IFN-inducible chemokine genes in the brain, and the levels of CXCL10 in the serum and cerebrospinal fluid prior to and during the encephalitic stage of trypanosome infection, and correlates these with sleep/wake changes in a rat model of the disease.

METHODOLOGY/PRINCIPAL FINDINGS

The expression of genes encoding IFN-γ, CXCL9, CXCL10, and CXCL11 was assessed in the brain of rats infected with Trypanosoma brucei brucei and matched controls using semi-quantitative end-point RT-PCR. Levels of CXCL10 in the serum and cerebrospinal fluid were determined using ELISA. Sleep/wake states were monitored by telemetric recording. Using immunohistochemistry, parasites were found in the brain parenchyma at 14 days post-infection (dpi), but not at 6 dpi. Ifn-γ, Cxcl9, Cxcl10 and Cxcl11 mRNA levels showed moderate upregulation by 14 dpi followed by further increase between 14 and 21 dpi. CXCL10 concentration in the cerebrospinal fluid increased between 14 and 21 dpi, preceded by a rise in the serum CXCL10 level between 6 and 14 dpi. Sleep/wake pattern fragmentation was evident at 14 dpi, especially in the phase of wake predominance, with intrusion of sleep episodes into wakefulness.

CONCLUSIONS/SIGNIFICANCE

The results show a modest increase in Cxcl9 and Cxcl11 transcripts in the brain and the emergence of sleep/wake cycle fragmentation in the initial encephalitic stage, followed by increases in Ifn-γ and IFN-dependent chemokine transcripts in the brain and of CXCL10 in the cerebrospinal fluid. The latter parameter and sleep/wake alterations could provide combined humoral and functional biomarkers of the early encephalitic stage in African trypanosomiasis.

Case-control, exploratory study of cerebrospinal fluid chemokines/cytokines and lymphocyte subsets in childhood Tourette syndrome with positive streptococcal markers

A longstanding question is whether neuroinflammation is present in children symptomatic for Tourette syndrome (TS) with positive streptococcal serology and throat cultures. The objective was to directly test for it using modern hypothesis-driven approaches. Profiling studies for 14 immune cell types (flow cytometry), 7 chemokines/cytokines (ELISA), oligoclonal bands, and other immunoglobulins were performed in this IRB-approved study of 5 children with TS and streptococcal markers compared to data from 26 non-inflammatory pediatric neurological controls. Subjects were well-characterized clinically and with standardized scales for tics and obsessions/compulsions. Three subjects with TS (60%) had positive throat cultures for Group A beta-hemolytic strep, five had elevated anti-deoxyribonuclease-B titers (mean=444), and 4 (80%) had elevated anti-streptolysin O titers (981). There were no significant differences between groups in the frequency of CSF B and T cell subsets or NK cells; the proportion of intracellularly-stained T helper type 1 (IFN-γ) or type 2 (IL-4) cells; the concentrations of B cell chemoattractants CXCL13, CXCL10; the B cell proliferation/survival cytokines BAFF and APRIL, or other chemokines (CCL19, CCL21, CCL22). None of the patients had positive CSF oligoclonal bands or an abnormal IgG index/synthesis rate. Parallel blood studies were negative. This novel study found no group CSF lymphocyte phenotypic abnormalities or elevated inflammatory mediators in childhood TS despite positive serology and throat cultures for Group A beta-hemolytic streptococci. It demonstrates feasibility of the methodology, and should serve as the basis for a larger study of putative streptococcal-associated neuroimmunological disorders.

B Cell, Th17, and Neutrophil Related Cerebrospinal Fluid Cytokine/Chemokines Are Elevated in MOG Antibody Associated Demyelination

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody (MOG Ab) associated demyelination represents a subgroup of autoimmune demyelination that is separate from multiple sclerosis and aquaporin 4 IgG-positive NMO, and can have a relapsing course. Unlike NMO and MS, there is a paucity of literature on immunopathology and CSF cytokine/chemokines in MOG Ab associated demyelination.

AIM

To study the differences in immunopathogenesis based on cytokine/chemokine profile in MOG Ab-positive (POS) and -negative (NEG) groups.

METHODS

We measured 34 cytokines/chemokines using multiplex immunoassay in CSF collected from paediatric patients with serum MOG Ab POS [acute disseminated encephalomyelitis (ADEM = 8), transverse myelitis (TM = 2) n = 10] and serum MOG Ab NEG (ADEM = 5, TM = 4, n = 9) demyelination. We generated normative data using CSF from 20 non-inflammatory neurological controls.

RESULTS

The CSF cytokine and chemokine levels were higher in both MOG Ab POS and MOG Ab NEG demyelination groups compared to controls. The CSF in MOG Ab POS patients showed predominant elevation of B cell related cytokines/chemokines (CXCL13, APRIL, BAFF and CCL19) as well as some of Th17 related cytokines (IL-6 AND G-CSF) compared to MOG Ab NEG group (all p<0.01). In addition, patients with elevated CSF MOG antibodies had higher CSF CXCL13, CXCL12, CCL19, IL-17A and G-CSF than patients without CSF MOG antibodies.

CONCLUSION

Our findings suggest that MOG Ab POS patients have a more pronounced CNS inflammatory response with elevation of predominant humoral associated cytokines/chemokines, as well as some Th 17 and neutrophil related cytokines/chemokines suggesting a differential inflammatory pathogenesis associated with MOG antibody seropositivity. This cytokine/chemokine profiling provides new insight into disease pathogenesis, and improves our ability to monitor inflammation and response to treatment. In addition, some of these molecules may represent potential immunomodulatory targets.

Characteristic Cytokine and Chemokine Profiles in Encephalitis of Infectious, Immune-Mediated, and Unknown Aetiology

Background

Encephalitis is parenchymal brain inflammation due to infectious or immune-mediated processes. However, in 15–60% the cause remains unknown. This study aimed to determine if the cytokine/chemokine-mediated host response can distinguish infectious from immune-mediated cases, and whether this may give a clue to aetiology in those of unknown cause.

Methods

We measured 38 mediators in serum and cerebrospinal fluid (CSF) of patients from the Health Protection Agency Encephalitis Study. Of serum from 78 patients, 38 had infectious, 20 immune-mediated, and 20 unknown aetiology. Of CSF from 37 patients, 20 had infectious, nine immune-mediated and eight unknown aetiology.

Results

Heat-map analysis of CSF mediator interactions was different for infectious and immune-mediated cases, and that of the unknown aetiology group was similar to the infectious pattern. Higher myeloperoxidase (MPO) concentrations were found in infectious than immune-mediated cases, in serum and CSF (p = 0.01 and p = 0.006). Serum MPO was also higher in unknown than immune-mediated cases (p = 0.03). Multivariate analysis selected serum MPO; classifying 31 (91%) as infectious (p = 0.008) and 17 (85%) as unknown (p = 0.009) as opposed to immune-mediated. CSF data also selected MPO classifying 11 (85%) as infectious as opposed to immune-mediated (p = 0.036). CSF neutrophils were detected in eight (62%) infective and one (14%) immune-mediated cases (p = 0.004); CSF MPO correlated with neutrophils (p<0.0001).

Conclusions

Mediator profiles of infectious aetiology differed from immune-mediated encephalitis; and those of unknown cause were similar to infectious cases, raising the hypothesis of a possible undiagnosed infectious cause. Particularly, neutrophils and MPO merit further investigation.

Meta-Analysis of Cytokines and Chemokines in Suicidality: Distinguishing Suicidal Versus Nonsuicidal Patients

BACKGROUND

Major psychiatric disorders are associated with inflammation. Aberrant cytokine and chemokine levels have been associated with psychiatric disorders and suicidal behavior. We performed a meta-analysis of cytokine and chemokine levels in patients with versus without suicidality and patients with suicidality versus healthy controls.

METHODS

We identified articles by searching MEDLINE, PsycINFO, and Thomson Reuters Web of Knowledge databases and the reference lists of identified studies.

RESULTS

Study inclusion criteria were met by 18 studies comprising 583 patients with suicidality, 315 patients without suicidality, and 845 healthy control subjects. Levels of interleukin (IL)-1β and IL-6 were significantly increased in blood and postmortem brain samples of patients with suicidality compared with both patients without suicidality and healthy control subjects (p < .05 for each). In vitro IL-2 production by peripheral blood mononuclear cells was significantly decreased in patients with suicidality compared with both patients without suicidality and healthy controls (p < .01 for each). Cerebrospinal fluid levels of IL-8 were significantly decreased in patients with suicidality versus control subjects (p < .05).

CONCLUSIONS

We found evidence for aberrant cytokine levels in blood, cerebrospinal fluid, and postmortem brain samples of patients with suicidality. Levels of IL-1β and IL-6 were most robustly associated with suicidality, and these cytokines may help distinguish suicidal from nonsuicidal patients. Rigorously designed longitudinal studies are needed to evaluate these associations further.

Interleukin-18 deficiency and its long-term behavioural and cognitive impacts in a murine model of pneumococcal meningitis

Pneumococcal meningitis often results in death or neurological sequelae, but the underlying pathogenetic mechanisms remain poorly understood. In C57BL/6J mice subjected to intracerebroventricular (icv) challenge with Streptococcus pneumoniae, the chemokine CCL2 and cytokines interferon-γ, interleukin (IL)-1β, IL-6 and tumour necrosis factor were prominently expressed in the brain during the acute phase of the disease. The upregulation of these immune mediators was markedly diminished in IL-18-deficient mice. Uninfected IL-18(-/-) mice exhibited decreases in anxiety phenotype and licking behaviour, and an increase in behavioural habituation, in an automated monitoring system (the IntelliCage). Without antibiotic intervention, a majority of IL-18(+/+) mice developed irreversible disease after icv S. pneumoniae but this was significantly improved by deleting IL-18 gene function. IL-18(+/+) mice cured of pneumococcal meningitis with four doses of ceftriaxone, initiated at 20 h post-inoculation, showed enduring sequelae. These included abnormal behavioural phenotypes featuring diurnal hypoactivity and nocturnal hyperactivity, light phobia and disrupted cognitive function. While the hyperactive phenotype was absent in the corresponding IL-18(-/-) survivors, cognitive impairments and behavioural deficits were still present. Overall, the results suggest that the high levels of cytokines and/or chemokines released after pneumococcal challenge provoked a series of pathological events, ultimately causing acute death. Furthermore, since only a subset of behavioural phenotypes were ameliorated in the pneumococcus-infected IL-18(-/-) mice, the pathological pathways causing mortality may be, at least in part, distinct from those leading to long-term neurological sequelae.

Feasibility of the use of combinatorial chemokine arrays to study blood and CSF in multiple sclerosis

Meningeal inflammation, including the presence of semi-organized tertiary lymphoid tissue, has been associated with cortical pathology at autopsy in secondary progressive multiple sclerosis (SPMS). Accessible and robust biochemical markers of cortical inflammation for use in SPMS clinical trials are needed. Increased levels of chemokines in the cerebrospinal fluid (CSF) can report on inflammatory processes occurring in the cerebral cortex of MS patients. A multiplexed chemokine array that included BAFF, a high sensitivity CXCL13 assay and composite chemokine scores were developed to explore differences in lymphoid (CXCL12, CXCL13, CCL19 and CCL21) and inflammatory (CCL2, CXCL9, CXCL10 and CXCL11) chemokines in a small pilot study. Paired CSF and serum samples were obtained from healthy controls (n=12), relapsing-remitting MS (RRMS) (n=21) and SPMS (N=12). A subset of the RRMS patients (n = 9) was assessed upon disease exacerbation and 1 month later following iv methylprednisone. SPMS patients were sampled twice to ascertain stability. Both lymphoid and inflammatory chemokines were elevated in RRMS and SPMS with the highest levels found in the active RRMS group. Inflammatory and lymphoid chemokine signatures were defined and generally correlated with each other. This small exploratory clinical study shows the feasibility of measuring complex and potentially more robust chemokine signatures in the CSF of MS patients during clinical trials. No differences were found between stable RRMS and SPMS. Future trials with larger patient cohorts with this chemokine array are needed to further characterize the differences, or the lack thereof, between stable RRMS and SPMS.

Chemokine levels and chemokine receptor expression in the blood and the cerebrospinal fluid of HIV-infected patients with cryptococcal meningitis and cryptococcosis-associated immune reconstitution inflammatory syndrome

BACKGROUND

Human immunodeficiency virus-infected patients with treated cryptococcal meningitis who start combination antiretroviral therapy (cART) are at risk of further neurological deterioration, in part caused by paradoxical cryptococcosis-associated immune reconstitution inflammatory syndrome (C-IRIS). We hypothesized that C-IRIS is associated with alterations of chemokine receptor expression on T cells and chemokine concentrations in cerebrospinal fluid (CSF) that enhance recruitment of T-helper 1 cells and/or myeloid cells to the central nervous system.

METHODS

In a prospective study of 128 human immunodeficiency virus-infected patients with cryptococcal meningitis who received antifungal therapy followed by cART, we examined the proportions of CD4(+) and CD8(+) T cells expressing CCR5 and/or CXCR3, in CSF and whole blood and the concentrations of CXCL10, CCL2, and CCL3 in stored CSF and plasma.

RESULTS

The proportion of CD4(+) and CD8(+) T cells expressing CXCR3(+)CCR5(+) and the concentrations of CXCL10, CCL2 and CCL3 were increased in CSF compared with blood at cART initiation (P < .0001). Patients with C-IRIS (n = 26), compared with those with no neurological deterioration (n = 63), had higher CSF ratios of CCL2/CXCL10 and CCL3/CXCL10 and higher proportions of CXCR3(+)CCR5(+)CD8(+)T cells in CSF compared with blood at cART initiation (P = .03, .0053, and .02, respectively).

CONCLUSION

CD8(+) T-cell and myeloid cell trafficking to the central nervous system may predispose patients to C-IRIS.

Characteristic cerebrospinal fluid cytokine/chemokine profiles in neuromyelitis optica, relapsing remitting or primary progressive multiple sclerosis

BACKGROUND

Differences in cytokine/chemokine profiles among patients with neuromyelitis optica (NMO), relapsing remitting multiple sclerosis (RRMS), and primary progressive MS (PPMS), and the relationships of these profiles with clinical and neuroimaging features are unclear. A greater understanding of these profiles may help in differential diagnosis.

METHODS/PRINCIPAL FINDINGS

We measured 27 cytokines/chemokines and growth factors in CSF collected from 20 patients with NMO, 26 with RRMS, nine with PPMS, and 18 with other non-inflammatory neurological diseases (OND) by multiplexed fluorescent bead-based immunoassay. Interleukin (IL)-17A, IL-6, CXCL8 and CXCL10 levels were significantly higher in NMO patients than in OND and RRMS patients at relapse, while granulocyte-colony stimulating factor (G-CSF) and CCL4 levels were significantly higher in NMO patients than in OND patients. In NMO patients, IL-6 and CXCL8 levels were positively correlated with disability and CSF protein concentration while IL-6, CXCL8, G-CSF, granulocyte-macrophage colony-stimulating factor (GM-CSF) and IFN-γ were positively correlated with CSF neutrophil counts at the time of sample collection. In RRMS patients, IL-6 levels were significantly higher than in OND patients at the relapse phase while CSF cell counts were negatively correlated with the levels of CCL2. Correlation coefficients of cytokines/chemokines in the relapse phase were significantly different in three combinations, IL-6 and GM-CSF, G-CSF and GM-CSF, and GM-CSF and IFN-γ, between RRMS and NMO/NMOSD patients. In PPMS patients, CCL4 and CXCL10 levels were significantly higher than in OND patients.

CONCLUSIONS

Our findings suggest distinct cytokine/chemokine alterations in CSF exist among NMO, RRMS and PPMS. In NMO, over-expression of a cluster of Th17- and Th1-related proinflammatory cytokines/chemokines is characteristic, while in PPMS, increased CCL4 and CXCL10 levels may reflect on-going low grade T cell and macrophage/microglia inflammation in the central nervous system. In RRMS, only a mild elevation of proinflammatory cytokines/chemokines was detectable at relapse.

Production of chemokines in respiratory syncytial virus infection with central nervous system manifestations

Respiratory syncytial virus (RSV) infection in children can be associated with acute encephalopathy. However, the roles of cytokines in the cerebrospinal fluid (CSF) of such patients remain unevaluated. In this study, a profile of 17 cytokines was determined for eight RSV-infected children with neurological complications. In one patient with high levels of 13 cytokines, a cytokine storm was considered to have occurred. Interleukin (IL)-6, IL-8, monocyte chemoattractant protein (MCP)-1, and macrophage inflammatory protein (MIP)-1β levels were also high in other patients. These data suggest that chemokines in CSF play roles in neurological complications in RSV-infected children.

Clinical study on CXCL13, CCL17, CCL20 and IL-17 as immune cell migration navigators in relapsing-remitting multiple sclerosis patients

BACKGROUND

There has been a growing evidence for the role of chemokines in the pathology of multiple sclerosis. Recently, there has been great emphasis placed on humoral immunity and the T(H)-17 response, which has not yet been thoroughly described in MS. The aim of this study was to investigate the role of specific chemokines involved in B-cell migration (CXCL13) and in the T(H)-17 immune response (IL-17, CCL17, CCL20).

METHODS

Using ELISA, the chosen chemokine concentrations were measured in the serum and cerebrospinal fluid of relapsing-remitting MS patients with both active and stable disease, and the relapse prediction rate was calculated.

RESULTS

We found that the CSF concentrations of CXCL13 in patients with RRMS both, during relapse and remission, were significantly higher than in controls. CCL17 and CCL20 were not detected in CSF in either of the groups, whereas serum CCL20 level was significantly higher in remission than during relapse. Intravenous methylprednisolone treatment of patients with relapse did not influence serum CXCL13 and CCL20 levels. However, it did lower CCL17 and IL-17 concentrations.

CONCLUSIONS

CXCL13 is an important mediator in MS that is strongly linked to the neuroinflammatory activity of the disease. However, more studies are needed for elucidating the roles of CCL17, CCL20 and IL-17 in MS pathology.

Cytokines and chemokines in viral encephalitis: a clinicoradiological correlation

Japanese encephalitis (JE) is the commonest encephalitis in South East Asia associated with high morbidity and mortality. Neuronal injury is attributed to a number of proinflammatory cytokines. This study evaluates cerebrospinal fluid (CSF) cytokines and chemokines in encephalitis and correlates these with clinical and magnetic resonance imaging (MRI) findings. We examined 14 patients with encephalitis (8 JE, 1 dengue, 5 nonspecific encephalitis) and 10 healthy controls. CSF cytokines (IL-1beta, IL-6, IL-10, IL-12p70, TNF-alpha, IL-8) and chemokines (IP-10, MCP-1, MIG, IL-8 and RANTES) were estimated using Cytometric Bead Array, compared with controls and were correlated with severity of encephalitis, radiological findings and presence of movement disorders. Median age of the patients was 25.5 (range 6-55 years); 6 had seizures, 10 movement disorders and 6 out of 11 had MRI abnormalities. The MRI abnormalities included thalamic involvement in 5, basal ganglia and mid brain in 3 each and cortical involvement in 2 patients. Both the patients with cortical involvement had seizures and 5 of the 10 patients with movement disorders had thalamic, basal ganglia and/or mid brain involvement. There was significant increase in IL-6 (p=0.01), RANTES (p=0.02) and IL-8 (p=0.02) in encephalitis compared to controls but there was no difference in IL12p70, TNF-alpha, IL-10, IL-1beta and MCP-1. Cytokines and chemokines did not correlate with severity of encephalitis, radiological changes and presence of movement disorders. CSF IL-6, IL-8 and RANTES were significantly higher in encephalitis patients compared to controls.

Longitudinal analysis of cytokines and chemokines in the cerebrospinal fluid of a patient with Neuro-Sweet disease presenting with recurrent encephalomeningitis

BACKGROUND

Neuro-Sweet disease (NSD) has recently been identified as Sweet disease with central nervous system (CNS) involvement characterized by multisystem neutrophilic infiltration. However, the pathogenesis of this disease remains unknown. Neutrophil and other inflammatory cell activities are influenced by many cytokines and chemokines, but to date, no studies have examined the levels of these factors in patients with NSD.

PATIENT AND METHODS

The patient presented with encephalomeningitis twice in one year and was diagnosed with NSD. We measured the levels of cytokines (i.e., IL-2, IL-4, IL-6, IL-10, IFN-gamma, and TNF-alpha) and chemokines (i.e., CCL2, CCL3, CCL5, CXCL8, CXCL10 and GM-CSF) in 10 CSF samples from the patient longitudinally for one year including those during two episodes of encephalomeningitis.

RESULTS

The elevations of IL-6, IFN-gamma, CXCL8 (IL8) and CXCL10 (IP10) were markedly higher than the levels in uninfected control subjects with neurological disorders. The levels of these cytokines and chemokines were statistically correlated with total CSF cell counts (p <0.01).

CONCLUSION

CD4+ helper T (Th) cells can be divided into the Th1 and Th2 subtypes according to their cytokine secretion patterns, and IFN-gamma and IP10 are the Th1-type cytokine and chemokine indicating the involvement of Th1 cells in NSD. In addition, the level of IL8, a specific neutrophil chemoattractant, correlated well with the neutrophil cell counts in CSF. Our data suggest the important roles of Th1 cells and IL8 in the pathogenesis of NSD.

Chemokine responses are increased in HIV-infected Malawian children with invasive pneumococcal disease

BACKGROUND

Chemokines play an important role in the recruitment and regulation of leukocyte traffic during bacterial infection. The aims of this study were to investigate the chemokine response to invasive pneumococcal disease (IPD) and to examine the influence of HIV infection on the chemokine response, pneumococcal bacterial loads, and outcome.

METHODS

We prospectively studied 95 children with IPD, and blood and cerebrospinal fluid (CSF) samples were taken at admission for the determination of chemokines, interferon-gamma (IFNgamma), and pneumococcal bacterial loads.

RESULTS

Plasma CXCL8 and CCL2, CSF CXCL8 and CCL4, and IFNgamma were significantly higher in HIV-infected children than in HIV-uninfected children. Blood and CSF pneumococcal bacterial loads correlated with plasma and CSF chemokines, respectively, and were higher in HIV-infected children compared with HIV-uninfected children. Among HIV-infected children, plasma concentrations of CXCL8 and CCL2 were significantly higher in nonsurvivors than in survivors, but CCL5 was significantly lower. HIV-infected and HIV-uninfected children with IPD had higher concentrations of chemokines (except CCL5) than acutely ill HIV-infected and HIV-uninfected children with no detectable bacterial infection. Male gender and low plasma CCL2 concentrations were shown to be independently associated with survival.

CONCLUSIONS

Chemokines, in particular CCL2, are associated with survival in IPD and correlate with pneumococcal bacterial loads, disease presentation, and outcome.

Changes in immune and glial markers in the CSF of patients with Complex Regional Pain Syndrome

Complex Regional Pain Syndrome is a severe chronic pain condition characterized by sensory, autonomic, motor and dystrophic signs and symptoms. The pain in CRPS is continuous, it worsens over time, and it is usually disproportionate to the severity and duration of the inciting event. This study compares cerebrospinal fluid (CSF) levels of pro- and anti-inflammatory cytokines, chemokines and several biochemical factors (glial fibrillary acidic protein (GFAP), the nitric oxide metabolites (nitrate plus nitrite), the excitatory amino acid neurotransmitter glutamate, calcium, total protein and glucose) in patients afflicted with CRPS to levels found in patients suffering with other non-painful or painful conditions. The aim of the study is to determine the degree of involvement of glial cells and immune system mediators in the pathophysiology of CRPS. There was no elevation or reduction of a CSF marker that was specific for CRPS patients. However, there were several patterns of markers that could be helpful in both elucidating the mechanisms involved in the disease process and supporting the diagnosis of CRPS. The most common pattern was found in 50% (11 out of 22) of the CRPS patients and consisted of; elevated IL-6, low levels of IL-4 or IL-10, increased GFAP or MCP1 and increases in at least two of the following markers NO metabolites, calcium or glutamate. The results from this and other similar studies may aid in elucidating the mechanisms involved in the pathophysiology of CRPS. A better understanding of these mechanisms may lead to novel treatments for this very severe, life-altering illness.

Cell surface adhesion molecules and cytokine profiles in primary progressive multiple sclerosis

OBJECTIVE

We evaluated the utility of adhesion molecule (AM) and cytokine/chemokine expressions in blood and cerebrospinal fluid (CSF) as markers of disease activity in primary progressive multiple sclerosis (PPMS).

METHODS

The expressions of AMs and the levels of 17 cytokines in patients with PPMS (n = 25) were compared with those in secondary progressive MS (SPMS) (n = 18) and controls (n =11) and correlated with the volumes of focal and atrophic changes on MRI.

RESULTS

The expressions of very late activation antigen 4 (VLA-4), lymphocyte function-associated antigen 1 (LFA-1) and intercellular adhesion molecule 1 (ICAM-1) in blood and CSF were higher in PPMS than in controls. Comparison between PPMS and SPMS showed higher levels of ICAM-1 in blood and CSF in PPMS, while the level of the vascular adhesion molecule (VCAM-1) was higher only in blood. There was no difference in the levels of cytokines in serum or CSF between PPMS and SPMS or controls, but evidence suggesting intrathecal synthesis of interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) was found in PPMS. The expressions of CSF VLA-4 in PPMS correlated with the total volume of cerebral lesions and the number of diffuse brain lesions in MRI, while the amount of LFA-1 in CSF correlated with the number of spinal T2 lesions. The level of serum MIP-1beta correlated with the T2 lesion load and EDSS score in PPMS.

CONCLUSIONS

The upregulated expressions of AMs in blood and CSF and evidence for intrathecal synthesis of MCP-1 and IL-8 in PPMS indicate the importance of inflammatory changes in the pathogenesis of PPMS.

Interleukin-6 and chemokines in the neuropsychiatric manifestations of systemic lupus erythematosus

OBJECTIVE

To define the cytokine and chemokine profile in cerebrospinal fluid (CSF) from patients with neuropsychiatric systemic lupus erythematosus (NPSLE).

METHODS

Forty-two SLE patients who had been hospitalized because of NP manifestations were studied. Patients were evaluated at hospitalization and 6 months later; a CSF sample was obtained at each evaluation. As controls, CSF from 6 SLE patients with septic meningitis, 16 SLE patients with no history of NP manifestations (non-NPSLE), and 25 patients with nonautoimmune diseases were also studied. Soluble molecules, including cytokines (interleukin-2 [IL-2], IL-4, IL-6, IL-10, tumor necrosis factor alpha [TNFalpha], and interferon-gamma [IFNgamma]) and chemokines (monocyte chemotactic protein 1 [MCP-1], RANTES, IL-8, monokine induced by IFNgamma [MIG], and interferon-gamma-inducible 10-kd protein [IP-10]), were measured with the use of cytometric bead array kits.

RESULTS

CSF levels of the following molecules were significantly increased in NPSLE patients as compared with non-NPSLE and nonautoimmune diseases control patients, respectively: IL-6 (32.7 versus 3.0 and 2.96 pg/ml), IL-8 (102.8 versus 29.97 and 19.7 pg/ml), IP-10 (888.2 versus 329.7 [P not significant] and 133.6 pg/ml), RANTES (3.8 versus 2.5 and 2.2 pg/ml), MCP-1 (401.7 versus 257.9 [P not significant] and 136.9 pg/ml), and MIG (35.4 versus 11.4 and 3.5 pg/ml). Low levels of IL-2, IL-4, IL-10, TNFalpha, and IFNgamma were found in all groups. All cytokines and chemokines, except TNFalpha, were significantly higher among the SLE patients with septic meningitis than among the NPSLE patients. Six months later and in the absence of NP manifestations, all elevated molecule levels, except RANTES, in patients with NPSLE had decreased significantly, and no differences were noted between the NPSLE and non-NPSLE groups.

CONCLUSION

A central nervous system response composed of IL-6 and chemokines, but not Th1/Th2 cytokines, is associated with NP manifestations in SLE patients.

Intrathecal upregulation of granulocyte colony stimulating factor and its neuroprotective actions on motor neurons in amyotrophic lateral sclerosis

To investigate cytokine/chemokine changes in amyotrophic lateral sclerosis (ALS), we simultaneously measured 16 cytokine/chemokines (interleukin [IL]-1beta, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12 [p70], IL-13, IL-17, interferon-gamma, tumor necrosis factor-alpha, granulocyte colony stimulating factor [G-CSF], macrophage chemoattractant protein-1 [MCP-1], and macrophage inflammatory protein-1beta) in cerebrospinal fluid (CSF) and sera from 37 patients with sporadic ALS and 33 controls using a multiplexed fluorescent bead-based immunoassay. We also conducted immunohistochemical analyses from 8 autopsied ALS cases and 6 nonneurologic disease controls as well as cell culture analyses of relevant cytokines and their receptors. We found that concentrations of G-CSF and MCP-1 were significantly increased in ALS CSF compared with controls. In spinal cords, G-CSF was expressed in reactive astrocytes in ALS cases but not controls, whereas G-CSF receptor expression was significantly decreased in motor neurons of spinal cords from ALS cases. Biologically, G-CSF had a protective effect on the NSC34 cell line under conditions of both oxidative and nutritional stress. We suggested that G-CSF has potentially neuroprotective effects on motor neurons in ALS and that downregulation of its receptor might contribute to ALS pathogenesis. On the other hand, MCP-1 correlated with disease severity, which may aggravate motor neuron damage.

Cytokines and chemokines in cerebrospinal fluid and serum of adult patients with acute disseminated encephalomyelitis

Cytokines and chemokines contribute to the pathogenesis of acute disseminated encephalomyelitis (ADEM). Using a multiplex immunochemiluminescence ELISA, we measured 8 Th1/Th2 cytokines and 18 chemokines in the cerebrospinal fluid (CSF) and serum of 17 ADEM patients, 14 multiple sclerosis (MS) patients, and 7 healthy controls (HCs). Relative to HCs, ADEM patients had significantly high mean CSF concentrations of chemokines with attractant/activating properties towards neutrophils (CXCL1 and CXCL7), monocytes/T cells (CCL3 and CCL5), Th1 cells (CXCL10), and Th2 cells (CCL1, CCL22, and CCL17). Mean CSF concentrations of CXCL7, CCL1, CCL22, and CCL17 were higher in ADEM than in MS, whereas those of CCL11 were lower in MS than in ADEM and HCs. CSF pleocytosis correlated with CSF concentrations of CXCL1, CXCL10, CCL1, CCL17, and CCL22. Most of the functionally homologous chemokines correlated with each other. CSF Th1/Th2 cytokines were not detectable in most samples. Their mean concentrations did not differ in the three groups, and the same held for serum cytokines and chemokines. Our data suggest that the upregulation of chemokines active on neutrophils and Th2 cells differentiates ADEM from MS inflammation, and that both Th1 and Th2 chemokines might be produced in ADEM. Chemokines upregulated in ADEM could become CSF biomarkers after a posteriori evaluations in unselected case series.

Serum and cerebral spinal fluid levels of chemokines and Th2 cytokines in Schistosoma mansoni myeloradiculopathy

Schistosomal myeloradiculopathy (SMR) is the most common neurological form of Schistosoma mansoni infection. In this study we investigated the expression of chemokines and Th2 cytokines in serum and cerebral spinal fluid (CSF) of SMR patients. SMR patients presented increased serum levels of CCL11/eotaxin and CCL24/eotaxin-2 when compared to controls. SMR patients also had higher levels of IL-13 in CSF. Thus, SMR patients present enhancement of both IL-13 and CCR3 acting chemokines, both of which may facilitate the expression of a Th2 response and Th2-dependent damage to the spinal cord. As this cytokine is responsible for promoting Th2 responses, this finding is in accordance to the view that Th2 cells are important in the immunological process against the S. mansoni.

A link between chemokine levels and disease severity in human African trypanosomiasis

Trypanosoma brucei gambiense infection is an important public health challenge in sub-Saharan Africa. This parasitic disease is difficult to diagnose due to insidious clinical signs and transient parasitaemias. The clinical course is marked by two stages of increasing disease severity. An early systemic parasitic invasion is followed by the development of a progressive meningo-encephalitis. During this latter stage, a broad spectrum of neurological signs appears, which finally lead to a demyelinating and fatal stage if untreated. Treatment is toxic and difficult to administer when the CNS is invaded. Therefore, accurate diagnostic methods for stage determination are needed. The classically used criteria are not sufficiently specific and mechanisms of parasite invasion through the blood-brain barrier remain poorly understood. As cytokines/chemokines are involved in the early recruitment of leukocytes into the CNS, this study has focused on their potential value to define the onset of CNS involvement. Levels of monocyte chemoattractant protein-1/CCL-2, macrophage inflammatory protein-1alpha/CCL-3, IL-8/CXCL-8, regulated upon activation T cell expressed and secreted (RANTES)/CCL-5 and IL-1beta were measured in paired sera and CSF from 57 patients and four controls. Patients were classified into three groups (stage 1, intermediate and stage 2) according to current field criteria for stage determination (CSF cell count, presence of trypanosomes in CSF and neurological signs). In sera, cytokine/chemokine levels were poorly related to disease stage. Only CXCL-8 was higher in stage 1 patients when compared with stage 2 and CCL-5 was higher in controls when compared with patients. In contrast, in CSF the expression of the selected cytokines, except CCL-5, was associated with the presence of neurological signs, demonstrating their diagnostic value. We observed a relationship between the presence of trypanosomes or trypanosome-related compounds in CSF and levels of IL-1beta, CXCL-8, CCL-2 and CCL-3. These cytokines and chemokines may be triggered by the parasite and hence are potential markers of CNS invasion.

CSF cytokine and chemokine profiles in acute disseminated encephalomyelitis

We simultaneously measured 16 cytokines/chemokines in cerebrospinal fluid (CSF) from 14 patients with acute disseminated encephalomyelitis (ADEM) and 20 controls using a fluorescent bead-based immunoassay. A variety of cytokines, such as IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IFN-gamma, TNF-alpha, G-CSF and MIP-1beta, were significantly elevated in ADEM. In particular, G-CSF showed a marked 38-fold increase compared to the control mean. Significant positive correlations with inflammatory parameters in CSF, such as cell counts and protein levels, were found for IFN-gamma, IL-6 and IL-8. In contrast, IL-17 produced by activated CD4(+) memory T cells was not increased. The results suggested that various cytokines related to activation of macrophages/microglias and Th(1) and Th(2) cells are upregulated in CSF in ADEM.

Measurement of thirteen biological markers in CSF of patients with Alzheimer's disease and other dementias

Cerebrospinal fluid (CSF) biological markers may be of valuable help in the diagnosis of dementia. The aim of the present study was to evaluate CSF levels of 13 potential biomarkers in patients with Alzheimer's disease (AD), frontotemporal lobe dementia, alcohol dementia, major depression and control patients without any neuropsychiatric disease. The study was performed using beta-amyloid 1-42 (Abeta42), total tau and phosphorylated tau-181 (P-tau181) as core markers. The ratio P-tau181/Abeta42 could significantly distinguish AD patients from all other diagnostic subgroups. CSF levels of 5 growth factors (HGF, GDNF, VEGF, BDNF, FGF-2) and 3 cytokines/chemokines (TNF-alpha, TGF-beta1, MIP-1alpha) did not significantly differentiate between the studied groups. However, depending on the degree of neurodegeneration (as expressed by the ratio P-tau181/Abeta42), patients with AD displayed significantly increased CSF levels of nerve growth factor (NGF) as compared to healthy controls. CSF levels of monocyte chemoattractant protein 1 (MCP-1) were found to be significantly increased with age in all groups but did not distinguish AD patients from healthy controls. The results confirmed the suitability of the ratio P-tau181/Abeta42 for the diagnosis of AD, while CSF levels of NGF and MCP-1 are less specific and reliable for AD. It is suggested that the increase in NGF depends on the extent of neurodegeneration of the AD type and the increase in MCP-1 on age.

Intrathecal Chemokine Synthesis in Mild Cognitive Impairment and Alzheimer Disease

BACKGROUND

Immunoreactivity for several chemokines and for their related receptors has been demonstrated in resident cells of the central nervous system, and the up-regulation of some of them is associated with pathological changes found in Alzheimer disease (AD).

OBJECTIVE

To determine interferon-gamma-inducible protein 10 (IP-10), monocyte chemotactic protein 1 (MCP-1), and interleukin 8 (IL-8) levels in cerebrospinal fluid (CSF) from subjects with amnestic mild cognitive impairment (MCI) and patients with AD as compared with age-matched controls.

PATIENTS

Thirty-eight subjects with amnestic MCI, 36 patients with AD, and 41 age-matched subjects with noninflammatory affections of the nervous system.

DESIGN

Evaluation of CSF chemokine production at time of diagnosis of MCI and AD; correlation with clinical and personal data. Longitudinal evaluation of subjects with MCI until conversion to AD.

RESULTS

Cerebrospinal fluid IP-10 concentration was significantly increased in patients with MCI and mild AD but not in patients with severe AD (Mini-Mental State Examination score <15), whereas MCP-1 and IL-8 levels were increased in patients with MCI and all patients with AD. A significant positive correlation between Mini-Mental State Examination score and CSF IP-10 or MCP-1 concentration was observed in patients with AD. No correlation between IP-10 levels and age was found, whereas MCP-1 and IL-8 levels correlated positively with age. Out of 38 subjects with MCI, 19 developed AD within a 1- to 3-year follow-up.

CONCLUSIONS

The presence of inflammatory molecules is likely to be a very early event in AD pathogenesis, even preceding the clinical onset of the disease, as demonstrated by subjects with MCI who developed AD over time. Interferon-gamma-inducible protein 10 is specifically increased in MCI and seems to decrease with the progression of AD, whereas MCP-1 and IL-8 are up-regulated also in late stages of the disease, suggesting a role in phases in which neurodegeneration is prevalent.

Immunity, neuroglia and neuroinflammation in autism

Autism is a complex neurodevelopmental disorder of early onset that is highly variable in its clinical presentation. Although the causes of autism in most patients remain unknown, several lines of research support the view that both genetic and environmental factors influence the development of abnormal cortical circuitry that underlies autistic cognitive processes and behaviors. The role of the immune system in the development of autism is controversial. Several studies showing peripheral immune abnormalities support immune hypotheses, however until recently there have been no immune findings in the CNS. We recently demonstrated the presence of neuroglial and innate neuroimmune system activation in brain tissue and cerebrospinal fluid of patients with autism, findings that support the view that neuroimmune abnormalities occur in the brain of autistic patients and may contribute to the diversity of the autistic phenotypes. The role of neuroglial activation and neuroinflammation are still uncertain but could be critical in maintaining, if not also in initiating, some of the CNS abnormalities present in autism. A better understanding of the role of neuroinflammation in the pathogenesis of autism may have important clinical and therapeutic implications.

Chemokines in multiple sclerosis: CXCL12 and CXCL13 up-regulation is differentially linked to CNS immune cell recruitment

Understanding the mechanisms of immune cell migration to multiple sclerosis lesions offers significant therapeutic potential. This study focused on the chemokines CXCL12 (SDF-1) and CXCL13 (BCA-1), both of which regulate B cell migration in lymphoid tissues. We report that immunohistologically CXCL12 was constitutively expressed in CNS parenchyma on blood vessel walls. In both active and chronic inactive multiple sclerosis lesions CXCL12 protein was elevated and detected on astrocytes and blood vessels. Quantitative PCR demonstrated that CXCL13 was produced in actively demyelinating multiple sclerosis lesions, but not in chronic inactive lesions or in the CNS of subjects who had no neurological disease. CXCL13 protein was localized in perivascular infiltrates and scattered infiltrating cells in lesion parenchyma. In the CSF of relapsing-remitting multiple sclerosis patients, both CXCL12 and CXCL13 were elevated. CXCL13, but not CXCL12, levels correlated strongly with intrathecal immunoglobulin production as well as the presence of B cells, plasma blasts and T cells. About 20% of CSF CD4+ cells and almost all B cells expressed the CXCL13 receptor CXCR5. In vitro, CXCL13 was produced by monocytes and at much higher levels by macrophages. CXCL13 mRNA and protein expression was induced by TNFalpha and IL-1beta but inhibited by IL-4 and IFNgamma. Together, CXCL12 and CXCL13 are elevated in active multiple sclerosis lesions and CXCL12 also in inactive lesions. The consequences of CXCL12 up-regulation could be manifold. CXCL12 localization on blood vessels indicates a possible role in leucocyte extravasation, and CXCL12 may contribute to plasma cell persistence since its receptor CXCR4 is retained during plasma cell differentiation. CXCL12 may contribute to axonal damage as it can become a neurotoxic mediator of cleavage by metalloproteases, which are present in multiple sclerosis lesions. The strong linkage of CXCL13 to immune cells and immunoglobulin levels in CSF suggests that this is one of the factors that attract and maintain B and T cells in inflamed CNS lesions. Therefore, both CXCL13 and CXCR5 may be promising therapeutic targets in multiple sclerosis.

Elevated interleukin-12 and CXCL10 in subacute sclerosing panencephalitis

Immunosuppression associated with measles virus (MV) can be demonstrated by cytokine production failure in subacute sclerosing panencephalitis (SSPE) and may have implications on the pathogenesis of the disease. Cytokines (IL-12, IL-10, IL-4, IL-17, IL-18, IFN-alpha, IFN-gamma) and chemokines (CXCL8, CXCL10, CCL2 and CCL5) were measured in the cerebrospinal fluid (CSF) and serum samples from 60 patients with SSPE, 36 patients with infectious and/or inflammatory (IN) and 28 with other non-inflammatory (NIN) neurological diseases by ELISA. IL-12 p70+p40 was elevated in CSF and sera of SSPE when compared to the NIN group. However, the CSF levels of IL-12 p70 alone were not increased, indicating an increase of p40. The CSF of SSPE patients also showed relatively higher levels of IL-10 than that of the NIN group. CXCL10 levels in CSF were significantly higher in SSPE, whereas CXCL8 was increased in sera compared to NIN. No difference was detected in IFN-gamma, IFN-alpha, IL-17, IL-18, IL-4 or CCL2 and CCL5 levels. These results demonstrate that immune response against MV in SSPE may be impaired, although some T cell/Th1 inducing stimulations are present.

Discordant plasma and cerebral spinal fluid cytokines/chemokines in relation to HIV-1-associated dementia

Monocytes and macrophages serve as HIV-1 reservoirs and may indirectly lead to HIV-1-associated dementia via neurotoxic cytokine/chemokine production. It remains unknown if peripheral monocytes and macrophages are responsible for the presence of circulating and cerebral spinal fluid cytokine/chemokine. The purpose of this evaluation was to determine the relationship between inflammatory and chemoattractant cytokine/chemokine in the periphery and the CNS among individuals with HIV-1-associated dementia and normal cognition. To accomplish this, we utilized specimens from the Hawaii Aging with HIV Cohort to assay plasma, cerebral spinal fluid, and cultured peripheral monocyte and macrophage supernatant cytokine/chemokines from individuals with HIV-1-associated dementia and normal cognition by ELISA, relative real-time PCR, and protein macroarrays. To further characterize the activated cells that may be responsible for HIV-1-associated dementia, inverse-PCR was used to identify sites of viral integration. Different mediators of inflammation, and chemoattraction from monocyte and macrophage supernatants, plasma, and cerebral spinal fluid were identified in HIV-1-associated dementia versus normal cognition. The data suggest unique pathways leading to cytokine/chemokine release in the periphery versus the brain region. This may have implications in delineating a cause and effect in HIV-1-associated dementia pathogenesis.

Patterns of protein expression in infectious meningitis: a cerebrospinal fluid protein array analysis

Seventy-nine cytokines, chemokines, and growth factors were measured by protein array analysis in the cerebrospinal fluid of patients with meningitis and controls. Several factors were found to be regulated, which have not been studied in the CNS before, e.g., macrophage inflammatory protein-1delta (CCL15) and neutrophil-activating peptide-2 (CXCL7). In pneumococcal meningitis, other new observations were an increase of macrophage migration inhibitory factor, monocyte chemoattractant protein-2 (CCL8), pulmonary and activation-regulated chemokine (CCL18), and macrophage inflammatory protein-3alpha (CCL20), and a sustained upregulation of several growth factors. In viral meningitis, new findings were an elevation of CCL8, thrombopoietin, and vascular endothelial growth factor.

The Clinical Benefit of Adjunctive Dexamethasone in Tuberculous Meningitis Is Not Associated with Measurable Attenuation of Peripheral or Local Immune Responses

Outcome from tuberculous meningitis (TBM) is believed to be dependent on the severity of the intracerebral inflammatory response. We have recently shown that dexamethasone improved survival in adults with TBM and postulated that the clinical effect would be associated with a measurable systemic and intracerebral impact on immunological markers of inflammation. Prolonged inflammatory responses were detected in all TBM patients irrespective of treatment assignment (placebo or dexamethasone). The inflammatory response in the cerebrospinal fluid was characterized by a leukocytosis (predominantly CD3(+)CD4(+) T lymphocytes, phenotypically distinct from those in the peripheral blood), elevated concentrations of inflammatory and anti-inflammatory cytokines, chemokines, and evidence of prolonged blood-brain barrier dysfunction. Dexamethasone significantly modulated acute cerebrospinal fluid protein concentrations and marginally reduced IFN-gamma concentrations; other immunological and routine biochemical indices of inflammation were unaffected. Peripheral blood monocyte and T cell responses to Mycobacterium tuberculosis Ags were also unaffected. Dexamethasone does not appear to improve survival from TBM by attenuating immunological mediators of inflammation in the subarachnoid space or by suppressing peripheral T cell responses to mycobacterial Ags. These findings challenge previously held theories of corticosteroid action in this disease. An understanding of how dexamethasone acts in TBM may suggest novel and more effective treatment strategies.

Intrathecal activation of the IL-17/IL-8 axis in opticospinal multiple sclerosis

There are two distinct subtypes of multiple sclerosis in Asians, opticospinal (OS-multiple sclerosis) and conventional (C-multiple sclerosis). In OS-multiple sclerosis, selective and severe involvement of the optic nerves and spinal cord is characteristic, though its mechanisms are unknown. The present study aimed to find out possible differences in the cytokine/chemokine profiles in CSF between OS-multiple sclerosis and C-multiple sclerosis and to delineate the relationships between these profiles and neuroimaging and pathological features. Sixteen cytokines/chemokines, namely interleukin (IL)-1beta, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12 (p70), IL-13, IL-17, interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha, granulocyte colony-stimulating factor (G-CSF), monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1beta (MIP-1beta), were measured simultaneously in CSF supernatants from 40 patients with relapsing-remitting multiple sclerosis (20 OS-multiple sclerosis and 20 C-multiple sclerosis) at relapse and 19 control patients with spinocerebellar degeneration (SCD), together with intracellular production of IFN-gamma and IL-4 in CSF CD4+ T cells. In CSF supernatants relative to controls, IL-17, MIP-1beta, IL-1beta and IL-13 were only significantly increased in OS-multiple sclerosis patients, while TNF-alpha was only significantly increased in C-multiple sclerosis patients, using a cut-off level of 1 pg/ml. IL-8 was significantly elevated in both OS-multiple sclerosis and C-multiple sclerosis patients. MCP-1 was significantly decreased in both OS-multiple sclerosis and C-multiple sclerosis patients, while IL-7 was only significantly decreased in C-multiple sclerosis patients. IL-17, IL-8 and IL-5 were significantly higher in OS-multiple sclerosis patients than in C-multiple sclerosis patients. The increases in IL-17 and IL-8 in OS-multiple sclerosis were still significant even after exclusion of the patients undergoing various immunomodulatory therapies. Assays of intracellular cytokine production revealed that both the IFN-gamma+IL-4- T-cell percentage and intracellular IFN-gamma/IL-4 ratio in CSF cells were significantly greater in C-multiple sclerosis patients than in controls. Contrarily, OS-multiple sclerosis patients showed not only a significantly greater percentage of IFN-gamma+IL-4- T cells than controls but also a significantly higher percentage of IFN-gamma-IL-4+ T cells than C-multiple sclerosis patients. Among the cytokines elevated in multiple sclerosis, only IL-8 showed a significant positive correlation with the Expanded Disability Status Scale of Kurtzke score. Both the length of the spinal cord lesions on MRI and the CSF/serum albumin ratio had a significant positive correlation with IL-8 and IL-17 in multiple sclerosis, in which the spinal cord lesions were significantly longer in OS-multiple sclerosis than in C-multiple sclerosis. Three of six spinal cord specimens from autopsied OS-multiple sclerosis cases demonstrated numerous myeloperoxidase-positive neutrophils infiltrating necrotic lesions. These findings strongly suggest that in OS-multiple sclerosis, in addition to the Th1 cell upregulation seen in C-multiple sclerosis, intrathecal activation of the IL-17/IL-8 axis inducing heavy neutrophil infiltration contributes to extensive spinal cord lesion formation.

Chemokine profile in the cerebrospinal fluid and serum of Vogt–Koyanagi–Harada disease

We analyzed the concentrations of four chemokines in the cerebrospinal fluid (CSF) and sera in Vogt-Koyanagi-Harada disease (VKH), an autoimmune uveomeningitis syndrome against melanocyte-associated proteins, with ELISA. CSF-CXCL10/IP-10 and CSF-CCL17/TARC were significantly elevated in VKH than in controls. In the majority of VKH cases and controls, CSF-CXCL10 was higher than serum-CXCL10, and CSF-CCL17 was lower than serum-CCL17. CCL11/Eotaxin was not different between groups. CSF-CCL2/MCP-1 was significantly lower in VKH than in control. The changes in VKH were essentially similar to those in multiple sclerosis, a known Th1-dominant condition.

Expression of Th1/Th2-Related Chemokine Receptors on Peripheral T Cells and Correlation with Clinical Disease Activity in Patients with Multiple Sclerosis

Th1 cells play an important role in the pathogenesis of multiple sclerosis (MS), a disease likely linked to an autoimmune process. We measured the levels of chemokines in serum or cerebrospinal fluid (CSF) samples by ELISA, and also studied the expression of Th1-related CXCR3/CCR5 chemokine receptors and Th2-related CCR4/CCR3 chemokine receptors on blood cells from MS patients using three-color flow cytometry. The Bonferroni correction was used for the statistical analysis. The levels of CXCL10, CCL3, and CCL5 in the CSF samples for the MS groups were significantly higher than those for the control group. However, the levels of CCL2 in both the CSF and serum samples for the remission group were significantly higher than those for the active group. The percentage of CXCR3-expressing CD4+ T cells in patients with MS was significantly elevated compared with the healthy controls. Moreover, MS patients in an active phase showed a more increased CD4+CXCR3+/CD4+CCR4+ ratio than patients in a remission phase. The increased percentage of CD4+CXCR3+ cells in the blood was associated with relapses in MS. This study suggested that the CD4+CXCR3+/CD4+CCR4+ ratio could be a sensitive maker of immune dysfunction in MS.

Th1 shift in CIDP versus Th2 shift in vasculitic neuropathy in CSF

To investigate the intra- and extracellular levels of various cytokines and chemokines in CSF in chronic inflammatory demyelinating polyneuropathy (CIDP) and vasculitic neuropathy (VN), 16 cytokines, IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12 (p70), IL-13, IL-17, IFN-gamma, TNF-alpha, G-CSF, MCP-1 and MIP-1beta, were measured in CSF supernatant by a multiplexed fluorescent bead-based immunoassay and intracellular production of IFN-gamma and IL-4 in CSF CD4+ T cells were simultaneously measured by flow cytometry in 14 patients with CIDP, 8 patients with VN and 25 patients with other noninflammatory neurologic diseases (OND). In the CSF supernatant, a significant increase of IL-17, IL-8 and IL-6, and a significant decrease of IL-4, IL-5 and IL-7 levels were detected in pretreated CIDP as compared with OND. A significant increase of IL-6, IL-8 and IL-10 levels was found in pretreated VN. Both IL-17 and IL-8 levels correlated strongly with CSF protein levels in CIDP, although the correlation of IL-6 levels was weak. In CSF CD4+ T cells, IFN-gamma+ IL-4- cell percentages were markedly elevated in CIDP compared with OND, but not in VN, resulting in a significant increase of intracellular IFN-gamma/IL-4 ratio in CIDP, even in the absence of CSF pleocytosis. The nonresponders to intravenous immunoglobulins (IVIGs) showed a significantly lower IFN-gamma- IL-4+ CD4+ T cell percentage, and tended to have a higher intracellular IFN-gamma/IL-4 ratio than the responders in CSF. Marked upregulation of Th1 cytokine, IL-17, and downregulation of Th2 cytokines, together with infiltration of IFN-gamma-producing CD4+ T cells are useful markers for CIDP, while several Th2 cytokines are upregulated in VN in CSF.

Proinflammatory cytokines and chemokines in humans with Japanese encephalitis

BACKGROUND

Japanese encephalitis virus (JEV), the mosquito-borne flavivirus, annually causes an estimated 35,000-50,000 encephalitis cases and 10,000-15,000 deaths in Asia, and there is no antiviral treatment. The role played by the immune response in determining the outcome of human infection with JEV is poorly understood, although, in animal models of flavivirus encephalitis, unregulated proinflammatory cytokine responses can be detrimental.

METHODS

We studied the innate, cellular, and humoral immune responses in 118 patients infected with JEV, of whom 13 (11%) died.

RESULTS

Levels of interferon (IFN)- alpha , the proinflammatory cytokine interleukin (IL)-6, and the chemokine IL-8 were all higher in the cerebrospinal fluid (CSF) of the nonsurvivors than of the survivors (P=.04, P=.006, and P=.04, respectively), as were both the IL-6 : IL-4 ratio in CSF (a marker of the balance of pro- and anti-inflammatory cytokines) and the level of the chemokine RANTES (regulated on activation, normally T cell expressed and secreted) in plasma (P=.03). In contrast, levels of immunoglobulin (Ig) M and IgG in CSF and of IgM in plasma were higher in the survivors (P=.035, P=.003, and P=.009, respectively). Levels of IFN- gamma and nitric oxide did not vary with outcome.

CONCLUSIONS

During JEV infection, elevated levels of proinflammatory cytokines and chemokines are associated with a poor outcome, but whether they are simply a correlate of severe disease or contribute to pathogenesis remains to be determined.

CSF chemokine levels in relapsing neuromyelitis optica and multiple sclerosis

The pathogenesis of relapsing neuromyelitis optica (RNMO) remains unknown. We, for the first time, studied the levels of four chemokines in the cerebrospinal fluid in RNMO with ELISA and compared the data with those in multiple sclerosis (MS) and control. CXCL10/IP-10 and CCL17/TARC were significantly elevated in both RNMO and MS. Conversely, CCL2/MCP-1 was significantly lower in MS, but not in RNMO, than in control. CCL11/Eotaxin was not different between groups. None of the four chemokines studied was significantly different between RNMO and MS.

Cytokines and chemokines in neuro-Behçet's disease compared to multiple sclerosis and other neurological diseases

Cytokines and chemokines in cerebrospinal fluid (CSF) can have implications on the pathogenesis of neuro-Behçet's disease (NB). CSF and serum samples from 33 patients with NB, 25 with multiple sclerosis (MS), 20 patients with infectious and/or inflammatory neurological diseases (IN) and 14 with other noninflammatory neurological diseases (NIN) were investigated by ELISA. In the CSF, CXCL10 levels were significantly higher in NB and IN than NIN and MS, whereas CXCL8 was increased in NB compared to NIN. CCL2 levels in MS CSF and sera were lower, whereas CXCL8 in MS sera was higher than the other groups. IL-12 was elevated in CSF of IN compared to NB and NIN and also in the CSF of MS compared to NIN. No difference was detected for IL-10 and IL-17. These results reflect that NB has a mediator pattern in resemblance with non-specific inflammations such as neuro-infections compared to autoimmune disorders such as multiple sclerosis, suggesting that a currently unknown infection might be the trigger of a vasculitic process in the central nervous system (CNS).

[Cerebrospinal fluid in multiple sclerosis]

Recently, a revised diagnostic criteria for multiple sclerosis(MS) was published. In this paper, the cerebrospinal fluid(CSF) findings in MS were reviewed, with reference to this criteria. CSF abnormality was defined by the presence of oligoclonal IgG bands and/or the presence of an elevated IgG index in the criteria. Some differences in the grade of pleocytosis and protein content, and the frequency of IgG abnormalities were revealed between Japanese and western MS patients. Other CSF findings such as antibodies against myelin proteins, cytokines and chemokines were also discussed.

Aberrated levels of cerebrospinal fluid chemokines in Guillain-Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy

Infiltration of spinal nerve roots and peripheral nerves by macrophages and T cells are rather consistent immunopathologic findings in patients with Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Chemokines play a central role in recruitment of leukocytes to inflamed tissue. Chemokines have been implicated in the pathogenesis of the experimental autoimmune neuritis (EAN), which represents an animal model of GBS, but the role of chemokines in GBS and CIDP is not clear. Since chemokines may be released into CSF from inflamed spinal nerve roots, we studied the concentrations of the chemokines MCP-1, MIP-1beta, MIP-3beta, IP-10, SDF-1alpha, RANTES, and SLC in the CSF by sandwich ELISA in patients over the course of GBS and CIDP, before and after immunomodulatory treatment. Controls consisted of patients with noninflammatory neurological disorders. Patients examined in the acute phase of GBS prior to treatment with intravenous high dose immunoglobulins (IvIg) had elevated CSF levels of MCP-1 (a chemoattractant for blood monocytes and dendritic cells) and IP-10 (a chemoattractant for T cells). Patients with CIDP examined prior to immunomodulatory treatment had elevated CSF levels of MIP-3beta (a chemoattractant for mature dendritic cells, naïve and recently activated T cells) and IP-10. Levels of MIP-3beta tended to decreased during follow-up in those CIDP patients responding favorably to immunomodulatory treatment. CSF levels of MCP-1 and IP-10 correlated with the CSF:plasma albumin ratio in both GBS and CIDP patients. In CIDP patients, CSF levels of MIP-3beta also correlated with the CSF:plasma albumin ratio. These data implicate MCP-1 and IP-10 in the pathogenesis of GBS, and IP-10 and MIP-3beta in the pathogenesis of CIDP.