TLR7 and systemic lupus erythematosus: To test whether TLR7 pathway hyperactivity could contribute to Ftx−/− lupus-like phenotype and to identify the targeted cell populations, we first measured the basal expression of cytokine genes normally induced upon activation of TLR7 pathway (i.e., Tnfα, Il-1β, Il-6, and Il-10) by RT-qPCR in BM or splenic Mo/MΦ, in splenic DC, and in splenic B cells of 1-year-old females (Fig. 6A).