[Effectors of in vivo delayed hypersensitivity in experimental flavivirus infections and vaccination against tick-borne encephalitis in mice].

The development of experimental infections caused by tick-borne encephalitis (TBE) virus, Langat virus and dengue virus type 2 in mice or the immunization of these animals with live yellow fever vaccine (prepared from strain 17D) and inactivated TBE vaccine were accompanied by the formation of delayed hypersensitivity (DH) to viral antigens, determined in vivo. In experimental TBE infection the effectors of DH were identified as T-lymphocytes whose action was specific and followed the rule of H-2 restriction. The T-effectors of DH, induced by inactivated TBE vaccine, had no cytotoxic effect on an infected syngeneic tissue culture and, after their adoptive transfer by intravenous injection in vivo, did not protect syngeneic recipients against TBE virus.