Another source of ROS in human SLE comes from T cells, some of which manifest enlarged mitochondria.5 14 We have shown previously that ROS can induce MAVS oligomerisation and IFN-I production in different cell types.15 We now observe that, similar to human SLE, mitochondrial enlargement and spontaneous MAVS oligomerisation arises in the MRL-lpr CD4–CD8– TCR-αβ+ subset. The gene discussed is CD4; the disease is systemic lupus erythematosus.