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.