Antibodies to DNA in the Blood of Patients with Tick-Borne Encephalitis

The relative levels of autoantibodies to native and denatured DNA (nDNA and dDNA, respectively) in the blood were compared in 55 patients with tick-borne encephalitis (TBE). Compared to healthy donors, the titers of antibodies (Ab) to nDNA and dDNA were significantly higher in 31% and 40% of TBE patients, respectively. The proportion of patients with an increased concentration of anti-nDNA Ab in the case of TBE (32%) was higher than among patients with multiple sclerosis (18%) and some other autoimmune diseases (6–18%) but comparable with that among patients with systemic lupus erythematosus (38%) and polymyositis (42%). In contrast to the patients with systemic lupus erythematosus and multiple sclerosis, the level of antibodies to nDNA in TBE patients was higher than that of anti-dDNA Ab. The coefficients of correlation between the levels of Ab to nDNA and dDNA were estimated for the entire group of TBE patients and for subgroups with different forms of the disease (temperature reactions, febrile form, and meningeal form). Analysis of correlation between the anti-DNA antibody titers and three standard biochemical markers of TBE (aspartate aminotransferase and alanine aminotransferase activities and total bilirubin) was carried out for 22 patients. A statistically significant correlation was revealed only between the level of Ab to nDNA and the marker enzyme activities, with the respective correlation coefficients being +0.44 and +0.48, respectively.