title: Long-term tracking of segmental bone healing mediated by genetically engineered adipose-derived stem cells: focuses on bone remodeling and potential side effects.
abstract: We previously showed that transplantation of adipose-derived stem cells (ASCs) engineered with hybrid baculovirus (BV) persistently expressing bone morphogenetic protein 2 (BMP2)/vascular endothelial growth factor (VEGF) into segmental defects in New Zealand White (NZW) rabbits led to successful defect reunion. By using microcomputed tomography and histology, here we further demonstrated that transplanting the hybrid BV-engineered ASCs into the massive defects (10 mm in length) at the femoral diaphysis of NZW rabbits resulted in trabecular bone formation in the interior via endochondral ossification and bone remodeling at 3 months post-transplantation. The progression of bone remodeling gave rise to the resorption of trabecular bone and conspicuous reconstruction of medullary cavity and cortical bone with lamellar structure at 8 months post-transplantation, hence conferring mechanical properties that were comparable to those of nonoperated femora. Importantly, X-ray, positron emission tomography/computed tomography scans, and histopathology revealed no signs of heterotopic bone formation and tumor formation. These data altogether attested that the genetically engineered ASCs and prolonged BMP2/VEGF expression not only healed and remodeled the stringent segmental defects, but also revitalized the defects into living bone tissues that structurally and biomechanically resembled intact bones without appreciable side effects, making it one step closer to translate this technology to the clinical setting.
authors.affiliation: 1 Department of Chemical Engineering, National Tsing Hua University , Hsinchu, Taiwan .
authors.forename: Chin-Yu
authors.initials: CY
authors.lastname: Lin
authors.forename: Yu-Han
authors.initials: YH
authors.lastname: Chang
authors.forename: Li-Yu
authors.initials: LY
authors.lastname: Sung
authors.forename: Chiu-Ling
authors.initials: CL
authors.lastname: Chen
authors.forename: Shih-Yeh
authors.initials: SY
authors.lastname: Lin
authors.forename: Kuei-Chang
authors.initials: KC
authors.lastname: Li
authors.forename: Tzu-Chen
authors.initials: TC
authors.lastname: Yen
authors.forename: Kun-Ju
authors.initials: KJ
authors.lastname: Lin
authors.forename: Yu-Chen
authors.initials: YC
authors.lastname: Hu
mesh_terms: D017667:Adipocytes / Q000166:cytology*; D000818:Animals; D055396:Bone Morphogenetic Protein 2 / Q000235:genetics / Q000378:metabolism / Q000627:therapeutic use*; D016723:Bone Remodeling / Q000502:physiology; D002478:Cells, Cultured; D003131:Combined Modality Therapy; D005264:Femoral Fractures / Q000175:diagnosis / Q000628:therapy*; D017102:Fracture Healing / Q000502:physiology; D015316:Genetic Therapy / Q000379:methods; D008137:Longitudinal Studies; D015202:Protein Engineering / Q000379:methods; D011817:Rabbits; D033581:Stem Cell Transplantation / Q000379:methods*; D013234:Stem Cells / Q000166:cytology*; D014162:Transfection / Q000379:methods; D016896:Treatment Outcome; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism / Q000627:therapeutic use*
chemical_list: C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A