Endocytosis of A fumigatus by endothelial cells.A fumigatus H237 conidia and germ tubes were incubated with endothelial cells for 45 minutes in the presence (□) or absence (▪) of the microfilament inhibitor, cytochalasin D. The number of organisms (orgs) endocytosed by the endothelial cells was determined by a differential fluorescence assay. Results are mean ± standard deviation of 3 experiments. *P < .001 compared with cells without cytochalasin D; §P < .05 compared with conidia.