Migration tracks of individual mature dendritic cells. Monocyte-derived dendritic cells from melanoma patients matured in the presence of TNF-&agr;, PGE2 and monocyte-conditioned medium were seeded on fibronectin-coated plates. Migration of individual cells was recorded by time-lapse cinematography for 100 minutes. Each square represents one dendritic cell at t = 0. Colors indicate different dendritic cell tracks. For details, see the article by de Vries et al. on page 12 of this issue.