NEW MODEL FOR BONE-RESORPTION STUDY IN-VITRO - HUMAN OSTEOCLAST-LIKE CELLS FROM GIANT-CELL TUMORS OF BONE

Cells harvested from 12 human giant cell tumors of bone and kept in cu lture for several passages were characterized for bone-resorbing capab ility, total and tartrate-resistant acid phosphatase activity, respons e to the calciotropic hormone calcitonin, cell proliferation, multinuc leation after passages, and presence of calcium sensing. Cells obtaine d from three tumors presented a complete panel of osteoclast character istics and maintained their multinuclearity after several passages. Ce lls from four other tumors increased their cAMP levels after treatment with calcitonin, and the other five apparently consisted of cells of stromal origin. These human cell populations with osteoclast character istics may provide valid in vitro models for the investigation of oste oclastic differentiation and activity.