TLR7 and systemic lupus erythematosus: We demonstrated previously that in vivo TLR8 restrains TLR7 on DCs, and that TLR8ko mice on the C57BL/6 background develop spontaneous lupus due to increased TLR7 signaling by DCs, while TLR8ko B cells or macrophages retain normal TLR7 signaling (10, 11, 26).