Histology, Osteoclasts

Excerpt

Functioning as vital cells in the bone matrix that maintains adequate bone mineral density through stimulating bone turnover and maintaining plasma calcium levels, osteoclasts are multinucleate cells that arise from hematopoietic stem cells. As a result, they are identifiable with the presence of CD13, CD14, and CD68 antigens and the lack of CD56, GrB, and Ki67 antigens. When they become activated through their receptor activator nuclear factor-kB (RANK), they function primarily to resorb bone through various acids and collagenases. They have a complex interplay with the immune system, which can stimulate them and result in various pathologies. Many bone diseases are associated with dysfunctional osteoclasts, such as osteoarthritis, osteoporosis, and osteopetrosis.