Ixodes ricinus tick saliva modulates tick-borne encephalitis virus infection of dendritic cells

Tick-borne encephalitis virus is an important human pathogen, naturally delivered into host skin via a tick bite. To examine the effects of the virus on dendritic cell biology, we cultured dendritic cells with two tick-borne encephalitis virus strains of different virulence in the presence of Ixodes ricinus tick saliva. Tick saliva treatment increased proportion of virus-infected cells, led to a decrease in virus-induced TNF-α and IL-6 production and to reduced virus-induced apoptosis. Our data indicate that tick saliva modulate virus-mediated alterations in dendritic cells, thus probably being involved in the early infection process in the host.