Whereas in mice DNASE1L3 is associated with clearance of apoptotic debris22,23, we show here that its distribution in humans is inconsistent with this, but rather indicates a role for DNASE1L3 alongside another lupus autoantigen, C1q24, in handling bacterial debris on the mucosal front line, adjacent to DN2 B cells. The gene discussed is DNASE1L3; the disease is systemic lupus erythematosus.