Objective : To study the preparation method of silane and bone morphogenetic protein⁃2 (BMP⁃2) on the nano⁃porous titanium surface and evaluate the osteogenic ability of the prepared surface. Methods : Silane and BMP⁃2 modified nano⁃porous titanium surfaces were constructed by alkali⁃heat treatment , silanization modification and BMP⁃2 grafting. Scanning electron microscopy , X ⁃ray photoelectron spectroscopy , infrared spectroscopy and water contact angle tests were used to characterize the changes of surface morphology , elements , functional groups and hydrophilicity during the preparation process. Immunofluorescence was used to observe the BMP⁃2 grafted on the surface. Cell activity test and cell fluorescence staining were used to analyze the ability to promote osteoblast adhesion and proliferation , and alkaline phosphatase activity was used to evaluate the ability to promote cell osteogenesis. Results : Material characterization results confirmed that silane and BMP⁃2 were successfully immobilized on the nano⁃porous titanium surface. Cell evaluation confirmed that the prepared surface not only significantly enhanced the adhesion and proliferation of osteoblasts , but also greatly enhanced the osteogenic ability of osteoblasts. Conclusion The constructed surface has better compatibility with osteoblasts and is expected to improve the osseointegration ability of titanium⁃based implants.

OBJECTIVETo compare the tubulogenesis capability of malignant glioma-derived microvessel endothelial cells (GDMEC) from human brain with that of ECV304 cells in a three dimentional model and to explore the significance of GDMEC in the study on angiogenesis.

METHODSThe GDMEC were isolated from malignant gliomas of human brain and purified by selective binding to the monoclonal antibody against CD105 bound to the magnetic MACS MicroBeads. GDMEC and endothelial-like cell line ECV304 were compared with their capabilities of formatting tubule-like structure (TLS) in the three dimentional collagen matrix, with or without inducement by various concentration of vascular endothelial growth factor (VEGF).

RESULTSThe obtained GDMEC had a high purification (98%) and could be successfully cultured in vitro. GDMECs formed more TLS than ECV304 cells of the same number and at the same time points. VEGF could induce rapid formation of TLS in a dose-dependent manner, however, ECV304 cells were less response to VEGF stimulation.

CONCLUSIONSGDMEC could maintain their endothelial characteristics and potential capability of angiogenesis. They were more response to VEGF than ECV304, therefore, more suitable for in vitro studies on tumor angiogenesis.

Brain Neoplasms ; blood supply ; Cells, Cultured ; Dose-Response Relationship, Drug ; Endothelial Cells ; drug effects ; Endothelium, Vascular ; cytology ; Glioma ; blood supply ; Humans ; Immunomagnetic Separation ; Microcirculation ; pathology ; Neovascularization, Pathologic ; Vascular Endothelial Growth Factors ; administration & dosage ; pharmacology