Platelet-Rich Plasma Pretreatment on Grit-Blasted Titanium Alloy for Enhanced Osteogenic Differentiation of Human Adipose-Derived Stem Cells

BACKGROUND: Adequate bone formation around titanium alloy implants is integral to successful implantation surgery. Stem cell-coated implants may accelerate peri-implant bone formation. This study investigates the effect of platelet-rich plasma (PRP) pretreatment on a titanium-alloy surface in terms of proliferation and osteogenic differentiation of human adipose-derived stem cells (hADSCs). METHODS: Allogenic leukocyte-depleted PRP was obtained from blood supernatants. The hADSCs were isolated from thigh subcutaneous fat tissue. Grit-blasted titanium plugs were used in two different groups. In one group, 200 µL of PRP was added to the grit-blasted titanium plugs. The hADSCs were seeded in two groups: grit-blasted titanium plugs with or without PRP. The number of hADSCs was measured after 4 hours, 3 days, and 7 days of culture using Cell Counting Kit-8. Osteogenesis of hADSCs was measured by using an alkaline phosphatase activity assay on days 7 and 14, and a calcium assay on days 14 and 21. Osteogenic gene expression was measured by using reverse transcription polymerase chain reaction analysis of alkaline phosphatase, osteocalcin, and type I collagen mRNA. The microscopic morphology of grit-blasted titanium plugs with or without PRP was examined with a field-emission scanning electron microscope using a JSM-7401F apparatus on days 1 and 7. RESULTS: Proliferation and osteogenic differentiation of hADSCs were found to be significantly higher on the grit-blasted titanium alloy preprocessed with PRP than the same alloy without pretreatment. Furthermore, a structural fibrillar mesh developed compactly on the grit-blasted titanium alloy with the PRP pretreatment. CONCLUSIONS: Our results demonstrate that a hADSC-based approach can be used for tissue-engineered peri-implant bone formation and that PRP pretreatment on the grit-blasted titanium alloy can improve proliferation and osteogenic differentiation of hADSCs.

Pre-Treatment of Titanium Alloy with Platelet-Rich Plasma Enhances Human Osteoblast Responses

Osseointegration, the histological direct bone-to-implant contact, is the ultimate goal of implant healing and the first prerequisite for long-term success of endosseous implants. It is well-known that metal implants with rough surfaces achieve better osseointegration than those with smooth surfaces in vivo. The implantation of metal materials into bone is always accompanied by bleeding. The implant surface is initially coated with blood and these initial events could determine subsequent osseointegration. However, there is little concordance between in vitro results and in vivo findings regarding the effect of surface roughness on osseointegration. Here, we show that the osteoblast response to metal surfaces pre-treated with platelets and plasma proteins elucidates the superior osseointegration of rough surfaced implants in vivo. We found that osteoblast attachment, proliferation, and osteoblastic differentiation were significantly higher on a rough titanium surface pre-treated with platelet-rich plasma (PRP) than on the same surface without pretreatment. Furthermore, we found that the three-dimensional fibrillar network formed on the rough surface of the titanium by PRP pre-treatment might enhance osteoblast responses. Our results demonstrate why osseointegration is found to be most active on metal implants with a rough surface in vivo. We anticipate that our assay would be a useful tool for mimicking the in vivo model of osseointegration. Because cellular responses to the titanium implant that are pre-treated with platelet and plasma proteins on their surfaces after the biomimetic process in vitro, may be more similar to the events that occur in vivo.

Successful general anesthesia for cervical spine fusion in a patient with spondyloepiphyseal dysplasia congenita: A case report

Spondyloepiphyseal dysplasia congenita (SEDC) is a kind of skeletal dysplasia, inheritable condition. The clinical features of SEDC are dwarfism, myopia with or without retinal detachment, coxa vara, thoracic dysplasia with respiratory failure and laryngotracheal stenosis. A point of particular concern to anesthetists is odontoid hypoplasia which, combined with ligamentous laxity, leads to atlantoaxial instability. We report successful general anesthesia for cervical spine fusion of a patient with SEDC.