title: Resorption of bone.
abstract: The cell-system responsible for resorption of bone is now considered to be a derivative of haematopoietic bone-marrow, not skeletal connective tissue. Consideration of mutant mice and rats, with defects of bone resorption giving osteopetrosis, suggests that the primary defect is of the professional scavengers, the mononuclear-phagocyte system, failing to recognise effete bone. To explain associated defects of thymic lymphocytes it is postulated that the mononuclear-phagocyte system may be activated to a major or minor extent by professional recognisers, thymic lymphocytes, as happens in some inflammatory reactions.
mesh_terms: D000818:Animals; D001862:Bone Resorption / Q000276:immunology / Q000473:pathology / Q000503:physiopathology; D005808:Genes, Recessive; D006801:Humans; D051379:Mice; D009154:Mutation; D010006:Osteoblasts / Q000473:pathology; D010010:Osteoclasts / Q000473:pathology; D010022:Osteopetrosis / Q000235:genetics / Q000276:immunology / Q000473:pathology / Q000503:physiopathology; D010587:Phagocytosis; D051381:Rats; D013601:T-Lymphocytes / Q000276:immunology