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A multitude of micro- and nano-surface structures have been developed to improve the clinical performance of endosseous titanium (Ti) implants. However, most of these surface structures only simulate the topographic elements on a micro- or nano-scale. Here, we describe a novel strategy to construct a bioinspired nano-micro hierarchical TiO2 clustered nanotubular surface structure using platelet derived growth factor-BB (PDGF-BB) covalently modified Ti implants, which highly mimic the structure of collagen in bone (Figure 1). This bio-activated hierarchical surface topography is referred to as NTPCP, nanotubular surface with PDGF-BB covalent modification via PhoA (11-hydroxyundecylphosphonic acid)/CDI (carbonyldiimidazole) chemistry. It provides a 3-dimentional spatial biomimetic structure for host cells, with negligible cytotoxicity (Figure 2) and satisfactory bio-activity for significantly enhancing cell attachment and osteogenic functions (including proliferation, extracellular matrix synthesis, and mineralization) of human bone mesenchymal stem cells (bMSCs) (Figure 3-6). Remarkably, we observed burst expression of osteocalcin (OCN)(Figure 5 and 7), which mirrored prominent bone formation around the NTPCP implants in a rat model(Figure 8). Our study provides a promising strategy of surface modification to improve osseointegration of endosseous Ti implants. Considering the regulatory effects of OCN on glucose homeostasis, NTPCP may be applied in diabetic patients in the future. The surface topography of clustered TiO2 nanotubular structure on Ti surface were scanned by FE-SEM and AFM. The surface roughness and wettability of prepared Ti samples were detected by AFM and DSA system respectively. The covalent modification of PDGF-BB on clustered TiO2 nanotubular structure on Ti surface was detected by XPS and immunofluorescent staining. The cell attachment and morphology of bMSCs on prepared Ti surfaces were observed by laser confocal scanning microscope and analyzed by image semi-quantitative analyzing. The cell proliferation and cytotoxicity determination were evaluated by MTT assay. The osteogenic genes expression were detected by q-PCR. The ECM mineralization were inspected by mineralized nodule staining and collegen staining. The in vivo study was performed by in vivo implantation model in rats. The OCN expression around Ti implants was observed by OCN immunofluorescent staining, The bone formation around Ti implants was analyzed by VG staining and image semi-quantitative analyzing.