BONE-FORMATION OF HUMAN OSTEOBLAST-LIKE CELLS IN A 3-DIMENSIONAL CELL-CULTURE - AN IN-VITRO MODEL FOR STUDIES OF SKELETAL DISORDERS

A three-dimensional (3-D) cell culture model was used for investigatio ns of the osteogenic activity of human cell lines, established from sk eletal tissues of healthy individuals and from patients presenting wit h osteoporosis, myositis ossificans, and osteosarcoma. This model faci litates bone formation by osteoblast-like cells in vitro and allows in vestigations of the osteogenic activity of osteoblasts. The cells were seeded on a sponge-like matrix of denatured collagen and cultured for a period of up to six weeks. Cells from bone tissues of healthy donor s showed extracellular matrix production in areas of high cellular den sity. A cell culture, established from bone tissue of a patient presen ting with osteoporosis, attached to the denatured collagen but showed very poor activity in producing extracellular matrix although the cell s remained viable over the entire culture period. Cell cultures from b iopsies of myositis ossificans and osteosarcomas formed large amounts of extracellular matrix with early signs of mineral deposition. Cells of the continuous osteosarcoma cell lines TE-85 and SAOS-2 attached to the denatured collagen but did not build up mineralizing osteoid. The se data illustrate the potential of the 3-D cell culture model to inve stigate the biopathology of human bone-derived cells of different orig in and from different skeletal disorders and to test factors or materi als which can modulate bone cell activity and bone formation in a defi ned in vitro environment.