Induction of suppressor cells in Japanese encephalitis virus infected mice.

Adoptive transfer of spleen cells obtained from mice primed with Japanese encephalitis virus (JEV) suppressed IgM antibody plaque forming cells (PFC) against JEV in the spleen. Similar suppression of PFC was also shown in vitro by adding primed spleen cells to JEV-stimulated spleen cell cultures. The suppressor activity appeared sharply in the third week after priming and persisted up to 6 weeks. By using various cell separation procedures it was found that the suppressor activity resided in the T cell enriched fraction and not in B cells or macrophages. Sensitivity of the cells to treatment with anti-Thy 1.2 antiserum and complement confirmed that suppressor cells were T lymphocytes. It was noted that the suppression was effective against dengue virus antigen also. Our findings thus show generation of suppressor T lymphocytes in JEV-infected mice.