Effect of α-AT/α-CLEC1A Abs and heparin on AT-mediated neutrophil shape rounding and ROS production inhibition. We investigated whether the rounding of neutrophils in shape and spontaneous ROS production inhibitory effects of AT are altered by the addition of α-AT Ab, α-CLEC1A Ab (10 μg/mL), and heparin (0-10 U/mL) as described in “Materials and methods.” Experiments were conducted using HBSS, HSA 3.0 μM, HRG 1.0 μM, AT 3.0 μM, and rAT 3.0 μM as test reagents. (A) The image shows a neutrophil incubated with a test reagent and an Ab. (B-E) Cell area and form factor. (F) Extracellular ROS production in the presence or absence Ab. (G-H) Form factor and cell area. (I) Extracellular ROS production with heparin. All experiments were performed using purified human neutrophils. For panel A, original magnification, ×20; scale bar, 50 μm. The results shown are the means ± SE of 12 fields in panels B-E,G-H or 6 wells in panel F or 3 wells in panel I. ∗P < .05 vs goat control.