Flow cytometry of cell-sieve sorted unlabeled primary cells isolated from porcine coccygeal intervertebral discs (IVD). A. (first raw) flow cytometry of passage 0 IVD cells separated by size with cell sieves of different mesh size and (second raw) change of cell size and composition if IVD cells were kept in monolayer culture for three passages (after three weeks). B. Flow cytometry of unlabeled primary cells comparing the performance of 2D monolayer (lower left) versus 3D alginate culture (lower right). Parameters of flow cytometer were constant for all measurements. Axes are FSC-A = forward scatter, SSC-A = side scatter.