Cytotoxicity and <i>in vitro</i> EC seeding.

Cell biocompatibility of decellularized samples was analyzed in a cytotoxicity and a cell seeding experiment. (A) Cytotoxic properties of samples from decellularized and native vessels were measured by adding tissue pieces to wells with pre-seeded HEK 293 cells. Cell viability was measured spectrometrically after 36h with an MTT assay.(B-C) Seeding with 75.000 HUVECs on the luminal side of the decellularized samples and incubation for 5 days. (B) Spectrometric analysis of the number of viable endothelial cells at day 5 with the MTS assay. (C) Visualization of alive endothelial cells with Calcein AM staining 5 days after. Pictures are taken in the green channel (488 nm) under identical microscopy conditions (n = 4 for all groups). Counterstaining was performed with DAPI. For observation of cell orientation and alignment as well as a general overview, pictures are presented as outlets (higher magnification) and inlets (lower magnification), scale bar equals 100 μm for both.