Human DCs produce ET-1 peptide upon maturation. ET-1 production by immature human DCs, DCs stimulated with TNF-α (DC + TNF-α), and DCs stimulated with S aureus (DC + SA). ET-1 concentration was measured in DC supernatants using ET-1 ELISA. Stimulated DCs produced statistically significantly higher ET-1 (P < .01) in comparison with unstimulated DCs.