FIG. 1.

The pictures showing the novel testing platform to assess the proaggregatory capacity of acellular collagen hydrogel or tissue-engineered vessel constructs in the ex vivo platelet Ca²⁺ signaling assay. (A) The three-dimensional sample to be tested was placed on a cellulose acetate frame with the center part permitting direct exposure to Fura-2- and DiOC₆-co-labeled washed human platelet suspension. (B) The sample was lowered down, allowing contact with the platelet suspension. (C) The picture of the assembled test sample with the presence of constant stirring of platelet suspension using a magnetic stir bar shown at the bottom. Platelet Ca²⁺ signaling in the platelet suspension was measured in real-time through Fura-2 fluorescence intensity, while platelet adhesion and aggregation on the surface of the samples were assessed by the imaging of DiOC₆-labeled platelets after removal of the sample from the cuvette. Color images available online at www.liebertpub.com/tec