ABSTRACT
Objective To investigate therapeutic effects of β-TCP/PLGA scaffolds seeded bone marrow mesenchymal stem cells (BMSCs) combing with hyperbaric oxygen (HBO) on bone defect with seawater immersing in rabbit radius.Methods BMSCs were seeded into the β-TCP/PLGA scaffolds to construct tissue engineering bone.60 New Zealand rabbits were created 1.5 cm bone defect in bilateral radius,and then bilateral wound limbs were immersed in seawater for 3 h.After debridement,all rabbits were randomly divided into 4 groups.In group A nothing was implanted into the bone defect.Only BMSCs was implanted in group B.BMSCs + HBO was given in group C.β-TCP/PLGA BMSCs + HBO was given in group D.At postoperative 4,8,12 weeks rabbits were sacrificed after radiography radius.X-ray radiography,HE staining,immunohistochemical observation were used to evaluate repairing effect of bone defect with seawater immersing.Results Radiographic analysis demonstrated that the bone defects were completely repaired with recanalization of the medullary cavity in group D,bone defects were partially repaired with partal recanalization of the medullary cavity in group C,bone defects were incompletely repaired in group B;bone defect repair unfinished and the broken ends were sclerous in group A.Each time point group D＞group C＞group B＞group A in callus grey value (P＜0.05).HE staining indicated after 12 weeks,a small amount of lainellar bone formated in group A;a small amount of lamellar bone formated in group B;a large amount of lamellar bone formated in group C;a large amount of lamellar bone formated in group D.Immunohistoehemical result indicated at postoperative 4 weeks,the expressions of osteocalcin(OCN) in each group were at high levels,the expressions decreased significantly at Postoperative 8 weeks,the expressions were at a low level at postoperative 12 weeks.At postoperative 4 and 8 weeks,the expression levels of OCN were group D＞ group C＞ group B＞group A (P＜0.05),there was no significant difference at postoperative 12 weeks between the 4 groups (P＞0.05).Conelusion the β-TCP/PLGA composite BMSCs combined hyperbaric oxygen is the effective method to repair seawater immersed bone defect in rabbit.