Et-1–treated CNS-ECs produce functional neutrophil chemotaxis factor. Confluent cultures of CNS-ECs were left untreated or treated with Et-1 (10−7 mol/L), TNF (1 ng/mL), or both Et-1 + TNF for 72 hours. Supernatants were then collected, and Et-1 or Et-1 + TNF supernatants were exposed to either goat anti–IL-8 antibody (200 μg/mL) or goat serum (200 μg/mL). The experimental supernatants were then placed in the lower compartment of the migration chamber. Freshly isolated PMNs were placed in the upper chamber. After 30 minutes, cells in the lower compartment were collected and counted using the trypan blue technique. The data are accumulated from 5 experiments and presented as the mean ± SEM. The data were calculated as the ratio of the number of cells migrating when exposed to experimental supernatants compared with media alone (media that had not been in contact with cells) times 100.
