title: Cellular responses to whitlockite.
abstract: Whitlockite crystals have been observed in both degenerating and normal articular cartilages. To determine their potential for inducing cartilage degeneration, we studied their ability to induce mitogenesis and synthesis and secretion of metalloproteases in vitro. Whitlockite crystals were found to stimulate cell proliferation and to stimulate synthesis and secretion of stromelysin and collagenase. However, they were less stimulatory than crystals that contained calcium (Ca) and phosphate without magnesium substitution for Ca. Whitlockite crystals elicit biologic cellular responses that suggest potential pathogenicity in arthritis, but are less potent than Ca phosphate crystals without magnesium.
authors.affiliation: Department of Medicine, Division of Rheumatology, Medical College of Wisconsin, 9200 W. Wisconsin Ave., Milwaukee, Wisconsin 53226, USA.
authors.forename: L M
authors.initials: LM
authors.lastname: Ryan
authors.forename: H S
authors.initials: HS
authors.lastname: Cheung
authors.forename: R Z
authors.initials: RZ
authors.lastname: LeGeros
authors.forename: I V
authors.initials: IV
authors.lastname: Kurup
authors.forename: J
authors.initials: J
authors.lastname: Toth
authors.forename: P R
authors.initials: PR
authors.lastname: Westfall
authors.forename: G M
authors.initials: GM
authors.lastname: McCarthy
mesh_terms: D002130:Calcium Phosphates / Q000494:pharmacology*; D002455:Cell Division; D002478:Cells, Cultured; D017364:Collagenases / Q000378:metabolism; D005347:Fibroblasts / Q000187:drug effects / Q000502:physiology; D006801:Humans; D015151:Immunoblotting; D019278:Matrix Metalloproteinase 3 / Q000378:metabolism; D008666:Metalloendopeptidases / Q000378:metabolism*
chemical_list: D002130:Calcium Phosphates; C021767:whitlockite; D017364:Collagenases; D008666:Metalloendopeptidases; D019278:Matrix Metalloproteinase 3