HAVCR2 and infection: The circulatory Tc cells in the RH group had significantly higher Tim-3 expression compared to that of the ME49 group at day 5 and 9 post-infection (Figures 2C,D, RH group vs. ME49 group: day 5, 5.00 ± 0.20 vs. 2.60 ± 0.61, P < 0.01; day 9, 4.53 ± 0.06 vs. 1.83 ± 0.75, P < 0.01).