[The effect of preparations of specific and nonspecific transfer-factor on the course of experimental tick-borne encephalitis].

Syrian hamsters subcutaneously inoculated with tick-borne encephalitis (TBE) virus were given transfer-factor (TF) preparations derived by different methods. The preparation of specific TF was obtained from the blood leukocytes of TBE convalescents. The nonspecific TF preparations were made of the lymphocytes of the tonsils removed from children with chronic tonsillitis outside the TBE focus. The effect of the TF preparations depended on the TBE virus strain and dose, TF preparation dosage schedule and characteristics. The specific TF preparations stimulated the development of acute fatal TBE after 3 injections at intervals of 0, 48 and 96 hours postinoculation with the virus. The preparations of nonspecific TF potentiate the infection after preliminary (24 hours) and simultaneous inoculation of the virus, producing transformation of asymptomatic infection to subacute TBE or exacerbation of the subacute process. A significant inhibition of TBE virus reproduction in spleen and brain tissues is observed after inoculation of a nonspecific TF F150 preparation 72 hours after virus inoculation, that is at the time when the virus has been already localized in the central nervous system. The results of the study indicate that the protective effect of TF is mainly associated with nonspecific immunopharmacological activity of the preparations.