CD274 and infection: Our recent in vitro data have shown that PD-L1 expression is activated in BMDMs as early as 2 hours after S. aureus infection 16, but the present study has found that robust expression of SLC7A11 appears after 12 hours of infection, it is reasonable to postulate that these two molecules might play distinct roles in initiation and potentiation of the suppressive effect on ROS levels, respectively, in the context of persistent S. aureus infection.