E. bovis in vitro culture used for microarray analyses. Bovine endothelial cells were infected with E. bovis sporozoites. Parasite development was followed microscopically, illustrated here at 4 h (A), 4 (B), 8 (C), 14 (D), 17 (E) and 20 (F) days after infection. Note the enormous enlargement of the host cells (D–F) and the change in nucleus morphology (a–f) in infected cells into a “fried egg”-type. White solid arrow = intracellular sporozoite; black opened arrow = trophozoite (4 days p.i.), immature meront I (8 and 14 days p.i.); white opened arrow = merozoite I; black solid arrow = nucleus of infected cell (all 630× magnification). (A color figure is available at www.vetres.org.)