title: Effect of bone morphogenetic protein-2 on tendon-bone integration in an in vitro cell culture.
abstract: The goal of this study was to evaluate the influence of bone morphogenetic protein-2 (BMP-2) on tendon-bone integration in a bovine in vitro cell culture. Seventy-two bovine tendons were cultivated over 3 months. The effects of BMP-2 were evaluated by generation in 4 subgroups. The groups differed in 2 parameters: the application of BMP-2 and the application of primary bovine osteoblasts. Results were analyzed biochemically by determining alkaline phosphatase activity and histologic tendon calcification, both markers for graft incorporation. Histological analysis demonstrated a positive effect of BMP-2 on the production of extracellular matrix and therefore the induction of osteogenesis. In addition, the results showed a superior cell ingrowth on the tendon in the BMP-2-stimulated groups. Calcium carbonate-like structures and organized ossification zones could only be detected in the BMP-2-stimulated tendons. The histological results matched those of the biochemical alkaline phosphatase analysis. The highest alkaline phosphatase activity was detected using BMP-2 stimulation in the first month (P<.001). High alkaline phosphatase values suggest high osteoblast activity and a high potential for mineralization. Furthermore, a positive effect of BMP-2 on fibroblasts existed with regard to the overall integration process. These results confirm the positive influence and triggering effect of BMP-2 on the mineralization process. Bone morphogenetic protein-2 seems to accelerate and optimize tendon-bone integration in the early process of graft incorporation. Besides the influence of BMP-2 on bovine osteoblasts, an additional positive effect of BMP-2 on bovine fibroblasts was detected; therefore, graft incorporation may be carried out by osteoblasts and fibroblasts.
authors: Department of Orthopaedics and Rheumatology, University Hospital Marburg, Baldingerstrasse, 35043 Marburg, Germany. struewer@med.uni-marburg.de
authors: Johannes
authors: J
authors: Struewer
authors: Moritz
authors: M
authors: Crönlein
authors: Ewgeni
authors: E
authors: Ziring
authors: Tim
authors: T
authors: Schwarting
authors: Marita
authors: M
authors: Kratz
authors: Steffen
authors: S
authors: Ruchholtz
authors: Thomas Manfred
authors: TM
authors: Frangen
mesh_terms: D000469:Alkaline Phosphatase / Q000032:analysis; D000818:Animals; D055396:Bone Morphogenetic Protein 2 / Q000494:pharmacology*; D001842:Bone and Bones / Q000187:drug effects* / Q000473:pathology; D002417:Cattle; D002478:Cells, Cultured; D036341:Intercellular Signaling Peptides and Proteins / Q000494:pharmacology*; D023421:Models, Animal; D016348:Osseointegration / Q000187:drug effects*; D010006:Osteoblasts / Q000187:drug effects; D010012:Osteogenesis / Q000187:drug effects; D013710:Tendons / Q000187:drug effects* / Q000473:pathology
chemical_list: D055396:Bone Morphogenetic Protein 2; D036341:Intercellular Signaling Peptides and Proteins; D000469:Alkaline Phosphatase