11:10-12:00, Rm 103

Development and regenerationE-17-25Identification of a new angiogenic factor during osteogenesis of humanmesenchymal stem cellJung-Min Kim¹ , ², Hong-In Shin³, Sun-Shin Cha⁴, Bok Sil Hong², Chang Sup Lee²,Sanguk Yun², Seyoung Lim¹, Jaeyoon Kim², Hyun-Jun Jang², Yun-Hee Kim²,Sung Ho Ryu²and Pann-Ghill Suh¹.¹School of Nano-Bioscience & Chemical Engineering, Ulsan National Institute of Science andTechnology, Ulsan, Korea, ²Division of Molecular and Life Sciences, Pohang University of Scienceand Technology, Pohang, Korea, ³Department of Oral Pathology, School of Dentistry, KyungpookNational University, Daegu, Korea, ⁴Korea Ocean Research and Development Institute (KORDI),Ansan, KoreaIn bone fracture repair process, cell-to-cell communication between osteoblasts andendothelial cells is considered as important event. We focused on secretory moleculesfrom osteoblasts might be involved in endothelial cell angiogenesis. We compared activityof conditioned medium from undifferentiated mesenchymal stem cells (MSCs) andosteoblasts on endothelial cells migration. We could observe that secretory moleculesfrom osteoblasts showed significant increases in eodothelial cells migration and one ofmolecules is protein CX. First, we could find the increased secretion level of protein CXaccording to the osteogenesis of MSC. And we identified protein CX as an angiogenicfactor and it had agiogenic activity in vitro and in vivo condition. Protein CX exerts itsangiogenic activity through FGFR-1 activation and in response to FGFR-1 antagonist andsiRNA of FGFR-1, protein CX-induced angiogenic activity was abolished. Finally, weexamined effect of protein CX in rat cranial defect model and we could observe thattreatment of protein CX enhanced bone regeneration by stimulating angiogenesis in thedefect site. We suggest here that protein CX is an important mediator between osteoblastand endothelial cell in bone fracture repair process.234 Korean Society for Biochemistry and Molecular Biology