Mouse Thymic Virus–Mediated Immunosuppression: Association with Decreased Helper T Cells and Increased Suppressor T Cells

Abstract

Mouse thymic virus (MTV) is a herpesvirus which, when administered to newborn mice, induces an extensive but temporary thymic necrosis associated with immunosuppression. In the present study, the T cell subsets in the thymus of MTV infected newborn C57BI/6 mice were evaluated at 4, 7, 14, 28, 56, and 84 days after infection, using labeled monoclonal anti-CD4 and anti-CD8 antibodies with two-color flow cytometry. At 7 and 14 days, the percentages of CD4⁺8⁻ and CD4⁺8⁺ cells were significantly decreased whereas the percentage of CD4⁻8⁺ cell was increased. At days 28 and 56 percentages had returned to normal. These results indicate that the virus has an affinity for CD4⁺ T cells (helper cells and their precursors). Increased percentage of CD4⁻8⁺ T cells (suppressor cells) is also associated with depressed Immune functions in MTV infected newborn mice.