[EO-10] Recruitment of remote bone marrow-derived cells to the implant surface immediately after implant installation
[Abstract]
[Objective]
Bone marrow is one of the main sources of stem cells. Bone marrow derived cells (BMDCs) could be recruited to various tissues in response to injury signal and differentiate to tissue-specific cell types. However, the contribution of BMDCs to the early stage of osseointegration process has not been completely elucidated. The aim of this study was to analyze the recruitment of remote bone marrow-derived cells to the implant surface immediately after implantation.
[Method]
Maxillary first and second molars of 4-week-old Spraque-Dawley rats (n=54) were extracted. One month after tooth extraction, those rats were irradiated to create immunodeficiency rats (9Gy whole body) and BMDCs expressing green fluorescent protein (GFP) were transplanted to both tibias. Two weeks after bone marrow transplantation, bone cavities were formed at the tooth extraction sites. Then, customized pure titanium implants were installed in both sides of the maxilla. In control group, bone cavities were created without implant installation. The rats were sacrificed (each group, n=6) at 0, 1, 3, 5, and 24 hours after operation. Samples were dissected and embedded in Poly Methyl Methacrylate (PMMA) resin (Technovit 9100 New) for preparing non-decalcified sections. Immunohistochemical analysis were conducted to observe GFP positive (+) cells in the adjacent area of implant surface. One way analysis of variance, followed by Tukey`s HSD test and Student`s t test were performed.
[Results and Discussion]
In test group, GFP(+) cells were observed in the gap between implant surface and bone at 3, 5, and 24h after implantation. And the amount of GFP(+) cells at 3, 5, and 24h were significantly higher than 0 and 1h. GFP(+) and GFP negative(-) cells were detected in 3, 5, and 24h in the control group. Especially, the total number of GFP(+) and GFP(-) cells in the test group was higher than that of control group. And the ratio of GFP(+) cells in the test group was also different from that of control group. It indicated GFP(+) BMDCs could be recruited at early stage of osseointegration process. However, participation of these cells at this stage is still unknown. BMDCs` contribution to osseointegration establishment should be elucidated by further study.
[Objective]
Bone marrow is one of the main sources of stem cells. Bone marrow derived cells (BMDCs) could be recruited to various tissues in response to injury signal and differentiate to tissue-specific cell types. However, the contribution of BMDCs to the early stage of osseointegration process has not been completely elucidated. The aim of this study was to analyze the recruitment of remote bone marrow-derived cells to the implant surface immediately after implantation.
[Method]
Maxillary first and second molars of 4-week-old Spraque-Dawley rats (n=54) were extracted. One month after tooth extraction, those rats were irradiated to create immunodeficiency rats (9Gy whole body) and BMDCs expressing green fluorescent protein (GFP) were transplanted to both tibias. Two weeks after bone marrow transplantation, bone cavities were formed at the tooth extraction sites. Then, customized pure titanium implants were installed in both sides of the maxilla. In control group, bone cavities were created without implant installation. The rats were sacrificed (each group, n=6) at 0, 1, 3, 5, and 24 hours after operation. Samples were dissected and embedded in Poly Methyl Methacrylate (PMMA) resin (Technovit 9100 New) for preparing non-decalcified sections. Immunohistochemical analysis were conducted to observe GFP positive (+) cells in the adjacent area of implant surface. One way analysis of variance, followed by Tukey`s HSD test and Student`s t test were performed.
[Results and Discussion]
In test group, GFP(+) cells were observed in the gap between implant surface and bone at 3, 5, and 24h after implantation. And the amount of GFP(+) cells at 3, 5, and 24h were significantly higher than 0 and 1h. GFP(+) and GFP negative(-) cells were detected in 3, 5, and 24h in the control group. Especially, the total number of GFP(+) and GFP(-) cells in the test group was higher than that of control group. And the ratio of GFP(+) cells in the test group was also different from that of control group. It indicated GFP(+) BMDCs could be recruited at early stage of osseointegration process. However, participation of these cells at this stage is still unknown. BMDCs` contribution to osseointegration establishment should be elucidated by further study.