Bone substitutes as carriers for transforming growth factor-beta(1) (TGF-beta(1)).
We studied the suitability of three different hydroxyapatite materials (Endobone, Bio-Oss and Algipore) as carriers for the bone growth promoting factor TGF-beta(1). The hydroxyapatite materials either were incubated for 24 h or directly loaded with hrTGF-beta(1) (Diagnostic Products Corporation, DPC) at a concentration of 10 ng hrTGF-beta(1)/mg. For the release experiment the hydroxyapatite materials covered with hrTGF-beta(1) were either suspended in pure phosphate buffered saline (PBS) or human serum albumin (HSA). The concentration of hrTGF-beta(1) was measured every 6 h the first day and then daily at the 2nd, 7th, 14th and 28th day. With Bio-Oss and Endobone the release of growth factor in HSA showed a two-phase kinetics. TGF-beta(1) reached a maximum concentration within the first 24 h and decreased almost linearly until day 28. With Algipore the concentration of growth factor reached a maximum after 12 h and showed a rapid decline until day 2. From day 2 the TGF-beta(1) concentrations remained low. Significantly, more TGF-beta(1) was released into HSA than into PBS. Our study suggests that the hydroxyapatite materials are suitable as TGF-beta(1) carriers.
Department of Orthopaedics, University of Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany. justus_gille@usa.net
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Gille
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Dorn
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Kekow
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Bruns
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Behrens
D001672:Biocompatible Materials; D018786:Bone Substitutes; D016503:Drug Delivery Systems; D017886:Durapatite; D006801:Humans; D008903:Minerals; D016212:Transforming Growth Factor beta / Q000008:administration & dosage*; D053773:Transforming Growth Factor beta1
C077540:Bio-Oss; D001672:Biocompatible Materials; D018786:Bone Substitutes; D008903:Minerals; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; C104266:endobon; D017886:Durapatite