Neutrophil transendothelial migration. The ability of¹¹¹Indium-labeled neutrophils from the patient and 2 normal donors to migrate across unstimulated endothelial cells (▪), or endothelial monolayers stimulated previously for 4 hours with TNF- (2 ng/mL) (), was studied. Normal endothelial cells (HUVEC) were used. After 90 minutes of incubation at 37°C, transendothelial migration of the patient’s neutrophils was equivalent to or exceeded that of normal donors. These data are representative of 3 experiments done in duplicate or triplicate in which the patient was compared with 2 normal donors and in which different normal donors were used in each experiment.