Effective Bone Regeneration Using Thermosensitive Poly(N-Isopropylacrylamide) Grafted Gelatin as Injectable Carrier for Bone Mesenchymal Stem Cells.
In this study, thermosensitive poly(N-isopropylacrylamide) (PNIPAAm) was grafted onto gelatin via atom transfer radical polymerization (ATRP). The chemical structure of PNIPAAm-grafted gelatin (Gel-PNIPAAm) was confirmed by XPS, ATR-IR, and (1)H NMR characterizations. Gel-PNIPAAm aqueous solution exhibited sol-to-gel transformation at physiological temperature, and was studied as injectable hydrogel for bone defect regeneration in a cranial model. The hydrogel was biocompatible and demonstrated the ability to enhance bone regeneration in comparison with the untreated group (control). With the incorporation of rat bone mesenchymal stem cells (BMSCs) into the hydrogel, the bone regeneration rate was further significantly enhanced. As indicated by micro-CT, histological (H&E and Masson) and immunohistochemical (osteocalcin and osteopontin) staining, newly formed woven bone tissue was clearly detected at 12 weeks postimplantation in the hydrogel/BMSCs treated group, showing indistinguishable boundary with surrounding host bone tissues. The results suggested that the thermosensitive Gel-PNIPAAm hydrogel was an excellent injectable delivery vehicle of BMSCs for in vivo bone defect regeneration.
State Key Laboratory of Organic-Inorganic Composites, Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology , 100029 Beijing, China.
Zhiwei
Z
Ren
State Key Laboratory of Organic-Inorganic Composites, Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology , 100029 Beijing, China.
Yang
Y
Wang
School and Hospital of Stomatology, Tianjin Medical University , 300070 Tianjin, China.
Shiqing
S
Ma
State Key Laboratory of Organic-Inorganic Composites, Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology , 100029 Beijing, China.
Shun
S
Duan
State Key Laboratory of Organic-Inorganic Composites, Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology , 100029 Beijing, China.
Xiaoping
X
Yang
School and Hospital of Stomatology, Tianjin Medical University , 300070 Tianjin, China.
Ping
P
Gao
School and Hospital of Stomatology, Tianjin Medical University , 300070 Tianjin, China.
Xu
X
Zhang
State Key Laboratory of Organic-Inorganic Composites, Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology , 100029 Beijing, China.
Qing
Q
Cai
D000180:Acrylic Resins / Q000494:pharmacology*; D000818:Animals; D001861:Bone Regeneration / Q000187:drug effects*; D001842:Bone and Bones / Q000166:cytology*; D002417:Cattle; D016923:Cell Death / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D004337:Drug Carriers / Q000737:chemistry*; D005780:Gelatin / Q000494:pharmacology*; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000494:pharmacology; D021621:Imaging, Three-Dimensional; D007150:Immunohistochemistry; D007267:Injections; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000187:drug effects; D010012:Osteogenesis / Q000187:drug effects; D044367:Phase Transition / Q000187:drug effects; D056951:Photoelectron Spectroscopy; D066244:Proton Magnetic Resonance Spectroscopy; D017207:Rats, Sprague-Dawley; D012867:Skin / Q000473:pathology; D012886:Skull / Q000187:drug effects / Q000473:pathology; D013696:Temperature; D055114:X-Ray Microtomography
D000180:Acrylic Resins; D004337:Drug Carriers; C052970:poly-N-isopropylacrylamide; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D005780:Gelatin
bone defect; bone mesenchymal stem cells; hydrogel; injectable; thermosensitive