Neutrophils adhere to cytokine-stimulated cultured endothelial cells. Phase-contrast photomicrograph of the adhesion of human neutrophils to control (left) and interleukin-1–treated (right) human umbilical vein endothelial monolayers taken at the end of a 10-minute adhesion assay. Reproduced with permission from American Society for Clinical Investigation.¹⁵