Fig 9. IFN-γ expression by T cells is required to control RRV infection in Rag1 ^-/- mice.

T cells were isolated from the spleens of 6–8 week-old WT and Ifng ^-/- mice via negative selection and 2.5 x 10⁶ T cells were adoptively transferred into three-to-four week-old Rag1 ^-/- mice i.p. one day prior to inoculation with 10³ PFU of RRV. (A-C) At 14 dpi, spleen and left quadriceps muscle tissues were harvested for flow cytometric analysis of the presence of T cells. (A) Representative flow plots showing the frequency of CD3⁺ and CD4⁺ or CD8⁺ T cells in the spleen and muscle tissues of Rag1 ^-/- mice that received either WT T cells or Ifng ^-/- T cells. Quantification of the (B) frequency and (C) total number of CD4⁺CD3⁺ or CD8⁺CD3⁺ T cells in the mice that received T cells. Horizontal bars indicate the mean. (D) At 14 dpi, the right quadriceps muscle was dissected, total RNA was isolated, and RRV genomes were quantified by absolute RT-qPCR. Horizontal bars indicate the mean. Data are combined from 2 independent experiments. P-value was determined by a two-way, unpaired t-test.