Mechanical interaction of intervertebral disc cells and their extracellular matrix

Annulus fibrosus (AF) cells of intervertebral discs (IVD) were cultured for 72h inside a 3D type I collagen matrix. When collagen matrix constructs were embedded with live AF cells, substantial matrix contraction (up to a 60% reduction in size) was observed. This contraction was not observed in constructs embedded with dead cells. Live cell collagen constructs were also comparably stronger. This contraction indicates a mechanical interaction between cells and their surrounding matrix.