Overview of the KOALA platform. (A) Comparison of the purification and chemotaxis protocols for the KOALA platform and Transwell assay. Other traditional assays that use live-cell imaging (ie, micropipette-based assays) take many hours to manually track the same number of cells that can be tracked with automated JEX tracking in 3 minutes. (B-E) Applications of the KOALA platform for neutrophil chemotaxis, including neutrophils migrating on endothelial cells (B); a 2D chemotaxis assay for neutrophils obtained from mice (C); a 2D chemotaxis assay for human primary neutrophils captured and sorted from a drop of whole blood (D); and neutrophil chemotaxis in a 3D matrix (E). Traditional purification methods and sample volumes shown in panel A are required for 3D neutrophil chemotaxis.