We. Gallwitz et al., 5-LIPOXYGENASE METABOLITES OF ARACHIDONIC-ACID STIMULATE ISOLATED OSTEOCLASTS TO RESORB CALCIFIED MATRICES, The Journal of biological chemistry, 268(14), 1993, pp. 87-94
Bone resorption requires cooperation between osteoclasts and mononucle
ar accessory cells by mechanisms which have not been elucidated. Since
multinucleated cells in giant cell tumors of bone have many phenotypi
c and functional characteristics of normal osteoclasts, we have examin
ed the interaction between the bone-resorbing multinucleated cells and
the distinct mono-nuclear stromal cells from these tumors. We have fo
und that these mononuclear cells produce an activity which stimulates
both giant cells from giant cell tumors and rodent osteoclasts to reso
rb bone in vitro. We have identified the activity and found that it re
presents several products of the 5-lipoxygenase pathway of arachidonic
acid metabolism, namely 5-hydroxyeicosatetraenoic acid and the leukot
rienes. These data indicate that 5-lipoxygenase metabolites stimulate
isolated osteoclasts to resorb bone in vitro and may represent a mecha
nism by which mononuclear stromal cells in human giant cell tumors com
municate with the giant cells. In addition, these results may explain
a possible mechanism for communication between accessory cells and ost
eoclasts involved in normal bone resorption.