CD274 and infection: In the next evaluation of the role of SLC7A11 in the expression of PD-L1 in vivo, we observed surprisingly no significant difference in the number of F4/80+PD-L1+ cells between Lyz2Cre-Scl7a11f/f mice and Slc7a11f/f mice without infection (Figure 6C and 6D), indicating that specific knockout of Slc7a11 in macrophages failed to activate the expression of PD-L1 under non-infectious condition.