TLR9 and systemic lupus erythematosus: In order to better understand the impact of Trib1 overexpression onIg (and notably IgG1) production, we stimulated total splenocytes and splenic sortedB cells with various stimuli, including a combination of LPS and IL-4, known toinduce the class-switching of B cells into IgG1-producing cells, and with several TLRagonists (TLR7, TLR9, and TLR1/2) known to play a role in lupus physiopathology inboth lupus mouse models and patients (31).