Study on CD31 expression in the process of the calf cortical with partial cancellous bone xenograft / 中国医师杂志

ABSTRACT

Objective To investigate the expression and tissue distribution of CD31 in the process of the calf cortical with partial cancellous bone xenograft, to explore the healing mechanism and relationship between bone remodeling and revascularization, and to provide a basis for the further study of tissue engi-neered bone.Methods Thirty-six New Zealand rabbits were selected as our experimental animals.All ani-mals were implanted with the calf cortical with partial cancellous bone.Specimens were procured at 4, 8, 12 and 24 weeks after surgery, respectively.The expression and tissue distribution of CD31 were observed in the process healing with general condition, X-ray, histology and immunohistochemistry.The image analy-sis computer system was used for quantitative analysis.The extent of revascularization and remodeling was separately represented by revascularization indexes and new bone areas.The relationship was studied be-tween bone remodeling and revascularization.Results ⑴ The X-ray showed significant healing.⑵ The positive expression of CD31 was seen in the whole process of bone xenograft and was different at various stage and sites.By the 4 weeks and 8 weeks postoperative,the strong positive expression was seen in the pe-ripheral soft tissue of graft bone, the callus of joint and the periphery of cartilage nests.Much positive ex-pression was seen in the cancellous bone.There was seen some single, cord, and cluster vascular endotheli-al cells.The positive expression was seen in the enlarged haversian canals and periphery.By the 24 weeks postoperative,the positive expression was seen in the enlarged haversian canals and periphery with increasing newborn capillaries.⑶ The correlation analysis between new bone areas and revascularization showed a closely positive correlation ( r =0.984).Conclusions The positive expression of CD31 was seen in the whole process of bone xenograft and was different at various stage and sites.The positive expression of CD31 reflected the extent of revascularization and bone remodeling of bone grafts.The extent of revascularization of bone grafts and bone remodeling showed a closely positive correlation.