Purpose: Previous in vitro studies have shown that DNA oligonucleotides (ODN) can be successfully used as anchor strands for the binding and retarded release of biologically active recombinant human bone morphogenetic protein 2 (rhBMP-2). The aim of the present study was to test the hypothesis that rhBMP-2 bound to the surface of titanium implants through hybridization with nano-anchored ODN strands is biologically active and can enhance the induction of osteogenic markers in peri-implant bone in vivo.
Materials And Methods: Custom-made, surface acid-etched (SAE) titanium discs and implants were coated with ODN anchor strands and subsequently hybridized with complementary ODN strands conjugated to rhBMP-2 (AS_CS_BMP-2).
Immobilization of bioactive molecules (BAMs) on a nanometer scale is of great interest for functionalization of implant and scaffold surfaces in current biomaterials research. A system for immobilization of one or more compounds is described, which is based on nanomechanical fixation of single-stranded nucleic acids into an anodic titanium oxide layer and their subsequent hybridization with BAMs conjugated to the respective complementary strands. This paper focuses on further development and in depth understanding of the immobilization system, as some of the major findings established for common sensor applications for immobilization of single-stranded DNA onto gold surfaces cannot be transferred to the TiO2 surface.
View Article and Find Full Text PDFThe aim of the present study was to test the hypothesis that immobilisation of bone morphogenic proteins on the surface of titanium implants through nano-anchored oligonucleotides can enhance peri-implant bone formation. Non-coding 60-mer DNA oligonucleotides (ODN) were anchored to the surface of custom made sandblasted acid etched (SAE) titanium screw implants through anodic polarisation, gamma-sterilised with a standard dose of 25 kGy, and were hybridised with complementary 30-mer strands of DNA oligonucleotides conjugated to rhBMP2. Blank SAE implants, SAE implants with nano-anchored ODN and SAE implants with nano-anchored ODN and non-conjugated rhBMP2 served as controls.
View Article and Find Full Text PDFPrimordial germ cells (PGCs) are the embryonic progenitors of sperm and egg cells. Mammalian PGCs are thought to actively migrate from the yolk sac endoderm over long distances across the embryo to reach the somatic genital ridges. The general principles of mammalian PGC development were discovered in mice.
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