Cellular responses to whitlockite

Whitlockite crystals have been observed in both degenerating and normal art icular cartilages. To determine their potential for inducing cartilage dege neration, 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 st romelysin and collagenase. However, they were less stimulatory than crystal s that contained calcium (Ca) and phosphate without magnesium substitution for Ca. Whitlockite crystals elicit biologic cellular responses that sugges t potential pathogenicity in arthritis, but are less potent than Ca phospha te crystals without magnesium.