PMNs treated with anti-CD157 or obtained from patients with PNH show efficient adhesion to HUVECs.51Cr-labeled PMNs from healthy donors (A) or PNH patients (C) were plated on activated HUVEC monolayers (in triplicate samples) in the presence or absence of 20 μg/mL of the indicated mAb and incubated at 37°C for 1 hour. After washing, adherent neutrophils were lysed with 2% Triton X-100 (100 μL) and the released radioactivity quantified in a γ counter. Percent specific adhesion was calculated following the formula: (51Cr released from adherent cells/total 51Cr added to each well) × 100. Results represent the mean ± SD of 3 independent experiments. *P < .001 versus all others. Comparison of cell spreading area between neutrophils treated with anti-CD157 or irrelevant IgG (B), or between neutrophils from PNH patients and healthy donors (D). PMNs were plated on HUVEC monolayers treated as described in Figure 4A-D. After 30 minutes, images were acquired by DIC using a × 60 oil immersion objective (1.4 NA; bar represents 10 μm) and analyzed by CellR Imaging software. Data are mean ± SEM of cells analyzed in 3 to 5 experiments. *P < .001.
