Abstract
In Central European tick-borne encephalitis (TBE) mechanisms of tissue destruction are poorly understood. To evaluate the contribution of immunological mechanisms to tissue injury, the authors immunohistochemically analyzed paraffin-embedded autoptic brain tissue of 26 human TBE cases. In the parenchymal compartment, there was a predominance of macrophages/microglia and cytotoxic T cells. In addition, it was found that granzyme B–expressing lymphocytes were in close contact with TBE-expressing neurons up-regulating caspase-3. These findings indicate that cellular and humoral pathways of the immune system, especially granzyme B–releasing cytotoxic T cells and macrophages/microglia, mainly contribute to tissue destruction in TBE.
The authors thank Judith Ludwig and Helga Flicker for excellent technical assistance.