TLR7 and systemic lupus erythematosus: There is accumulating evidence that patients with SLE display phenotypes that are consistent with increased TLR7 signalling associated with elevated IgD−CD27− double-negative B cells and, more specifically, the CXCR5−CD11c+ subset (also known as DN2 B cells or age-associated B cells (ABCs)) in the peripheral blood1, and excessive accumulation of extrafollicular helper T cells16.