ALTERED CYTOKINE GENES EXPRESSION BY CONA-ACTIVATED SPLEEN-CELLS FROMMICE INFECTED BY LYMPHOCYTIC CHORIOMENINGITIS VIRUS

The intravenous injection of mice with lymphocytic choriomeningitis vi rus (LCMV) induces a rapid and long-lasting immunodeficiency. T lympho cytes from 7-day-infected mice do not proliferate in vitro in response to ConA stimulation, do not produce IL-2 but display high affinity IL -2 receptors on their membrane. The non-coordinated regulation of thes e genes suggested that other cytokine-encoding genes may also be affec ted in their regulation. We have thus analyzed the expression of the g enes encoding different cytokines transcribed during spleen cell activ ation by GonA. The genes encoding T lymphocyte-derived cytokines can b e classified in three groups: the genes expressed similarly by normal and LCMV-cells (the p55 and the p75 chains of the IL-2 receptor [1]), the genes under expressed in LCMV-cells (IL-2, IL-3, IL-4 and IL-5) an d the genes over expressed by these cells (GM-CSF and IFN-gamma). Thes e results show that the viral infection has provoked a profound altera tion of the overall regulation of the genetic program that follows T l ymphocyte activation. Since T cell activation depends strictly on acce ssory cell-derived cytokines, we measured the level of transcription o f IL-1, IL-6 and TNF-alpha; and our data show that the expression of t hese genes is equivalent in normal cells and in cells from LCMV-infect ed mice.