Analysis of CCL-4, CCL-17, CCL-20 and IL-8 concentrations in the serum of patients with tick-borne encephalitis and anaplasmosis

The Role of Chitinase 3-Like-1 (YKL-40) and Proinflammatory Biomarkers in the Pathogenesis of Pediatric Tick-Borne Encephalitis in a Polish Cohort

Background

Chitinase 3-like-1 (CHI3L1), also known as YKL-40, is a potential biomarker for neuroinflammatory conditions. It is upregulated in Alzheimer's disease, multiple sclerosis, and traumatic brain injury. However, its involvement in pediatric tick-borne encephalitis (TBE) has not been addressed yet. This study aimed to evaluate CHI3L1 and its relationship with other inflammatory cytokines, blood-brain barrier (BBB) integrity, immune response, and disease severity in pediatric patients with TBE.

Patients and Methods

A total of 22 pediatric TBE patients hospitalized in Bialystok, Poland were included in this study. Participants were categorized as having meningoencephalitis (n=6) or meningitis (n=16). The integrity of the brain-blood barrier (BBB) was assessed using the albumin quotient (albQ). Biomarker indices were calculated to account for variations in BBB permeability. The concentrations of CHI3L1, CCL2, chemerin, CXCL2, IFN-γ, IL-1-β, IL-4, IL-6, IL-13, and TNF-α in both serum and CSF, were measured using the Luminex Multiplex Assay od admission and two weeks later when symptoms resolved.

Results

CSF and serum concentrations of CHI3L1 did not differ between the encephalitis and meningitis cases. After adjusting for BBB permeability, the CHI3L1 index was 2.4-fold lower in patients with encephalitis than in those with meningitis (P=0.008). There was a post-treatment reduction of CHI3L1, IL-6, and TNF-α CSF concentrations. We also found and improvement in BBB permeability in younger children but in older albQ remained abnormal. Correlation analysis revealed associations between CHI3L1 levels and pro-inflammatory markers, notably chemerin, IL-6, and TNF-α, across both clinical groups.

Conclusion

Our findings suggest that CHI3L1 CSF levels reflect the inflammatory activity in pediatric TBE and may help to differentiate between meningoencephalitis and meningitis. The observed interactions between CHI3L1 and other cytokines underscore its potential involvement in inflammatory response to the virus. The prolonged disruption in BBB integrity in older children might reflect age-dependent differences in the severity of TBE. These insights advance our understanding of TBE pathogenesis in children and support further investigation of CHI3L1 as a biomarker for TBE diagnosis and management.

The assessment of usefulness of cytokines and other soluble mediators as the predictors of sequalae development in various forms of tick-borne encephalitis (TBE)

AIM

The aim of the study was to assess the usefulness of cytokines and other soluble mediators in differentiation between severe and mild course of tick-borne encephalitis (TBE) as well as the predictor of sequalae development.

MATERIAL AND METHODS

122 patients (mean age 47.66 ± 14.77 years, 43 females, 79 males) with TBE were included in the study. Concentrations of 82 cytokines, growth factors, selectins, matrix metalloproteinases and other soluble mediators were measured in serum and CSF samples according to the manufacturer's instruction on a Bio-Plex 200 System using the custom made Luminex assays. Enzyme-linked immunosorbent assays for the quantitative detection of human IL-26, IL-29 IL-22, CXCL12 were performed.

RESULTS

No significant differences between serum concentrations of examined factors between group with sequelae and group with complete recovery were observed. In the CSF the concentrations of GM-CSF, Il-1α, Il-2, Il-4, Il-6, Il-12p70, Il-17A, CXCL1, CXCL6, Il-8, CCL4, CCL20, TRAIL, CD40L, MMP8 were significantly higher in patients who developed sequelae than in patients with complete recovery. For TRAIL concentration over 26.65 pg/ml in CSF the probability of sequalae development was 10.5 higher. In case of CCL20 - the concentration over 21.38 pg/ml in CSF the odds ratio was 6.429 times. For MMP-8 over 4210.54 pg/ml, the odds ratio was 11.222 times.

CONCLUSIONS

TRAIL, CCL-20 and MMP-8 are promising biomarkers of prediction of the sequalae development of TBE. Pro-inflammatory cytokines IL-8, IL-1, IL-2, IL-12, IL-17A also associate well with the risk of sequelae and could be further evaluated as prognostic markers in TBE, individually or as elements of a larger model.

Human granulocytotropic anaplasmosis-A systematic review and analysis of the literature

Human granulocytotropic anaplasmosis (HGA) is a zoonotic tick-borne bacterial infection caused by Anaplasma phagocytophilum. While most cases are reported from North America, HGA has been recognized as an emerging disease in several regions of the world in recent decades. Most available data comes from case reports, case series and retrospective studies, while prospective studies and clinical trials are largely lacking. To obtain a clearer picture of the currently known epidemiologic distribution, clinical and paraclinical presentation, diagnostic aspects, complications, therapeutic aspects, and outcomes of HGA, we systematically reviewed the literature and analyzed and summarized the data. Cases of HGA are reported from all continents except from Antarctica. HGA primarily presents as an unspecific febrile illness (88.5% of the cases) often accompanied by thrombocytopenia (71.8% of the cases), abnormal liver injury tests (66.7% of the cases), and leukopenia (49.8% of the cases). Although we found complications reported in a total of 40.5% of the reviewed cases and severe and even life-threatening complications are not infrequent (e.g. acute renal failure 9.8%, multi organ failure 7.5%, ARDS 6.3%, a.o.), sequelae are rare (2.1% of the cases) and lethality is low (3.0% of the cases). Treatment with doxycycline shows a rapid response, with the fever subsiding in the majority of patients within one day of starting treatment. Unlike in human monocytotropic ehrlichiosis (HME), reports of opportunistic infections complicating HGA are rare. HGA during pregnancy does not appear to be associated with unfavorable outcomes. In addition, our analysis provides some evidence that HGA may differ in clinical aspects and laboratory characteristics in different regions of the world. Overall, the data analyzed indicates a non-negligible bias in reporting/publication, so a certain degree of caution is required when generalizing the data.

Lipid mediators of cerebrospinal fluid in response to TBE and bacterial co-infections

Tick-borne diseases are caused by monoinfection or co-infection with different pathogens, including viruses, bacteria and protozoa. Tick-borne diseases are usually accompanied by oxidative stress which promotes the modifications of the host's lipid metabolism. The aim of the study was to compare total antioxidant status and the level of lipid mediators in the cerebrospinal fluid in response to tick-borne encephalitis (TBE) and bacterial co-infections that cause diseases such as that is Lyme borreliosis (LB) and human granulocytic anaplasmosis (HGA). In our study cerebrospinal fluid samples were obtained from 15 patients with TBE and 6 patients with TBE co-infection with LB and/or HGA at admission and after treatment. Control group consisted of 14 patients in whom meningitis was excluded. Total antioxidant status, levels of lipid peroxidation products, endocannabinoids and eicosanoids (determined by liquid and gas chromatography-mass spectrometry) were compared between the groups. It was found that in TBE patients, total antioxidant status was decreased and accompanied by increased levels of lipid peroxidation products (4-HNE, MDA, isoprostanes and neuroprostanes), major endocannabinoids (AEA and 2AG), and eicosanoids (both anti-inflammatory and pro-inflammatory), which generally declined after treatment. On the other hand, in co-infections, significant changes in the levels of some lipid mediators were observed even after the treatment. TBE alone or along with bacterial co-infections promote redox balance disturbances in the cerebrospinal fluid leading to oxidative stress and increased metabolism of phospholipids in the brain tissue reflected in the level of lipid peroxidation products and lipid mediators. Changes in the level of lipid mediators in patients with co-infections after treatment suggest further intensification of metabolic disturbances rather than their resolution.

Comparison of laboratory and immune characteristics of the initial and second phase of tick-borne encephalitis

Tick-borne encephalitis (TBE) usually has a biphasic course which begins with unspecific febrile illness, followed by central nervous system involvement. Because TBE is not yet suspected during the initial phase, knowledge of early TBE pathogenesis is incomplete. Herein we evaluated laboratory and immune findings in the initial and second (meningoencephalitic) phase of TBE in 88 well-defined adult patients. Comparison of nine laboratory blood parameters in both phases of TBE revealed that laboratory abnormalities, consisting of low leukocyte and platelet counts and increased liver enzymes levels, were predominately associated with the initial phase of TBE and resolved thereafter. Assessment of 29 immune mediators in serum during the initial phase, and in serum and cerebrospinal fluid (CSF) during the second phase of TBE revealed highly distinct clustering patterns among the three groups. In the initial phase of TBE, the primary finding in serum was a rather heterogeneous immune response involving innate (CXCL11), B cell (CXCL13, BAFF), and T cell mediators (IL-27 and IL-4). During the second phase of TBE, growth factors associated with angiogenesis (GRO-α and VEGF-A) were the predominant characteristic in serum, whereas innate and Th1 mediators were the defining feature of immune responses in CSF. These findings imply that distinct immune processes play a role in the pathophysiology of different phases of TBE and in different compartments.

An Updated Review of Recent Advances in Neurosyphilis

Neurosyphilis is caused by Treponema pallidum invading the central nervous system, of which the incidence is increasing worldwide. Due to its variable clinical manifestations, diagnosis of neurosyphilis remains challenging, especially the asymptomatic form. This review focuses on recent advances in neurosyphilis, including epidemiology, clinical manifestations, laboratory findings, comorbidities, diagnosis, treatment, prognosis, and basic research. The expansion of men who have sex with men and the infection of human immunodeficiency virus mainly accounted for the increasing incidence of neurosyphilis. The rate of some historically described forms of neurosyphilis in the pre-antibiotic era declined significantly; atypical features are more prevalent. Neurosyphilis, regarded as a great mimicker for neuro-ophthalmic, audio-vestibular, and psychiatric disorders, often presents concomitantly with other diseases, including metabolic disorders. Studies on long non-coding RNAs, miRNAs, chemokines, and metabolites in peripheral blood and cerebrospinal fluid may facilitate exploring the pathogenesis and identifying novel biomarkers of neurosyphilis. The drug resistance of Treponema pallidum to penicillin has not been reported; ceftriaxone was proposed to be more effective than penicillin, whereas few randomized controlled trials supported this view. This study may pave the way for further research, especially the diagnosis and treatment of neurosyphilis.

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.