[The effect of antigen-specific suppression induced by flaviviruses on the formation of an antigen-specific...

The effect of experimental flavivirus infection on the formation of antigen-induced immunosuppression in mice was studied. For this purpose, BALB/c mice with asymptomatic infection caused by Langat or West Nile virus were inoculated with supraoptimal doses of sheep erythrocytes and then checked for the capacity to respond again with production of hemolysin-synthesizing cells to the challenge with the optimal dose of the same antigen. The effect of the antigen-induced immunosuppression was found to be enhanced against the background of Langat or West Nile virus infection. The effect was most marked in case of priming with a supraoptimal dose of sheep erythrocytes inoculated at 4-6 days of flavivirus infection. The aggravation of the antigen-specific immunological defect against the background of the infectious process was demonstrated to be associated with the activation by flaviviruses of the T-suppressor link of immunoregulation under conditions of supraoptimal antigenic effect on the host.