Extended Data Fig. 7: LCMV-Arm infection of FlipFlop mice.

(a) Detection of virus-specific T cells by viral tetramers. Staining of T cells by H-2D^b/GP33 and I-A^b/GP66 viral peptide tetramers in the spleens of uninfected B6 and FlipFlop mice. Numbers in profiles indicate frequency of cells in each box (n=3/strain, representative of 3 independent experiments). (b) Experimental model for virus infection of mixed BM chimeras shown in Fig. 6d-g. Partner BM cells (CD45.2) from B6 or FlipFlop mice were mixed with donor BM cells (CD45.1) from B6 mice at a 1:1 ratio and injected into irradiated B6 host mice (CD45.1). Mice were infected with LCMV-Arm 8-10 wks after reconstitution. (c) Circulating virus titer (FFU/ml, geometric mean±SD) in the serum of infected mice (day 8) (B6: n=6, Prf^KO: n=5, MHC-II^KO: n=4, 3 independent experiments). *** P<0.001 (Mann-Whitney unpaired t-test). (d) Gate for CD45.1⁺TCRβ⁺CD8⁺ cells in infected spleen from BM chimeras. (e) Virus-specific T cells in mixed BM chimeras. H-2D^b/GP33 vs CD44 profile of B6-origin CD8 T cells (CD45.1⁺TCRβ⁺) in the spleens from infected (day 8) or uninfected mixed BM chimeras. Numbers in profiles indicate frequency of cells in each box (day 8, n=3-4/group, 2 independent experiments). (f) CD44 vs IFN-γ profile of B6-origin CD8 T cells (CD45.1⁺TCRβ⁺) in the spleens from infected (day 8) or uninfected mixed BM chimeras. Splenocytes were stimulated with or without GP33 peptide. Numbers in profiles indicate frequency of cells in each box (n=3-4/group, 2 independent experiments).