Figure 5. aPL-mediated NET release can be blocked by inhibition of TLR4, but not TLR2.

A, Control neutrophils were stimulated with control human IgG, an anti-β₂GPI monoclonal (CL1), or pooled IgG from 5 APS patients (all 10 μg/ml) for 3 hours. Control treatments were with LPS (100 ng/ml) and PMA (20 nM). Some samples were pretreated with TAK-242, a TLR4 inhibitor, at 5 or 10 μM. NET release was scored by immunofluorescence microscopy. B, Control neutrophils were stimulated as indicated (concentrations as in panel A) for 3 hours. Some samples were pretreated with anti-TLR4, anti-TLR2, or isotype (10 and 25 μM). NET release was scored by immunofluorescence microscopy. For all panels, bars represent mean and SEM; n=5 independent experiments per condition. *p<0.05, **p<0.01, ***p<0.001, and ns=not significant.