Matrix metalloproteinases (MMPs) play an important role in central nervous system infections. We analysed the levels of 8 different MMPs in the cerebrospinal fluid (CSF) of 89 adult patients infected with tick-borne encephalitis (TBE) virus and compared them with the levels in a control group. MMP-9 was the only MMP that showed significantly increased CSF levels in TBE patients. Serum MMP-9 levels were subsequently measured in 101 adult TBE patients at various time points during the neurological phase of TBE and at follow-up. In addition, serum MMP-9 was analysed in 37 paediatric TBE patients. Compared with control levels, both paediatric and adult TBE patients had significantly elevated serum MMP-9 levels. In most adult patients, serum MMP-9 levels peaked at hospital admission, with higher serum MMP-9 levels observed in patients with encephalitis than in patients with meningitis. Elevated serum MMP-9 levels were observed throughout hospitalisation but decreased to normal levels at follow-up. Serum MMP-9 levels correlated with clinical course, especially in patients heterozygous for the single-nucleotide polymorphism rs17576 (A/G; Gln279Arg) in the MMP9 gene. The results highlight the importance of MMP-9 in the pathogenesis of TBE and suggest that serum MMP-9 may serve as a promising bioindicator of TBE in both paediatric and adult TBE patients.

• Keywords
• Cerebrospinal fluid, Matrix matalloproteinase, Neuroinfection, Tick-borne encephalitis,
• MeSH
• Biomarkers MeSH
• Child MeSH
• Adult MeSH
• Polymorphism, Single Nucleotide MeSH
• Encephalitis, Tick-Borne * diagnosis   cerebrospinal fluid   MeSH
• Humans MeSH
• Matrix Metalloproteinase 9 genetics   MeSH
• Encephalitis Viruses, Tick-Borne * genetics   MeSH
• Check Tag
• Child MeSH
• Adult MeSH
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Biomarkers MeSH
• Matrix Metalloproteinase 9 MeSH
• MMP9 protein, human MeSH Browser