Viljanen V V, Lindholm T S
Institute of Medical Technology, University of Tampere, Finland.
Ann Chir Gynaecol. 1997;86(3):255-9.
The purpose of this study was to determine, if there is any difference in the osteoinductive response between xenogeneic and allogeneic bone morphogenetic protein (BMP) in the skull defect assay model.
The skull samples of two experimental series were chosen for uniform radiomorphometric measurement. In the xenogeneic BMP group (X-group), 52 mg of native moose (Alces alces) BMP (mBMP) was implanted in six 22-mm sheep midline skull defects, and in the allogeneic BMP (A-group), 8 mg of native sheep BMP (sBMP) was used in six same size parietal skull defects. The formation of new bone was confirmed histologically and the quantity of it was measured radiomorphometrically at 16 weeks after implantation from the standardized radiographs using a common flatbed scanner and image processing software, the mean grey scale intensity (radiopacity) multiplied by the original defect area giving the new bone volume. This was divided by the milligram amount of implanted BMP to get the value for comparison of BMP activities.
The control defects in both groups, implanted with 13 mg of type IV collagen, showed that the defects did not heal spontaneously during the follow-up time. In the X-group, the healing percentage was 92.4 +/- 3.0%, the calculated average bone volume (ABV)/mg being 12.4 +/- 0.5 units, whereas in the A-group the healing percentage was 62.9 +/- 8.5% and ABV/mg 60.9 +/- 6.7. Hence the activity per milligram proved to be more than four-fold with allogeneic compared to xenogeneic BMP. However, when the difference in spontaneous healing of the defects in the two series was taken into consideration, only slight but not significant difference (P = 0.077) of activity could be demonstrated between xenogeneic (5.7 +/- 1.7) and allogeneic BMP (9.05 +/- 3.7).
The result is in concordance with the previous published results showing that no significant immune inhibition is seen after a single implantation of xenogeneic BMP in an orthotopic site.
本研究旨在确定在颅骨缺损检测模型中，异种骨形态发生蛋白（BMP）和同种异体骨形态发生蛋白的骨诱导反应是否存在差异。
选取两个实验系列的颅骨样本进行统一的放射形态计量学测量。在异种BMP组（X组），将52毫克天然驼鹿（驼鹿属）BMP（mBMP）植入6个22毫米的绵羊中线颅骨缺损处；在同种异体BMP组（A组），将8毫克天然绵羊BMP（sBMP）用于6个相同大小的顶骨颅骨缺损处。植入16周后，通过组织学确认新骨形成，并使用普通平板扫描仪和图像处理软件，从标准化X光片中放射形态计量学测量新骨量，平均灰度强度（不透射线性）乘以原始缺损面积得出新骨体积。将其除以植入BMP的毫克数，得到BMP活性比较值。
两组植入13毫克IV型胶原蛋白的对照缺损显示，在随访期间缺损未自发愈合。在X组，愈合率为92.4±3.0%，计算得出的平均骨体积（ABV）/毫克为12.4±0.5单位；而在A组，愈合率为62.9±8.5%，ABV/毫克为60.9±6.7。因此，与异种BMP相比，同种异体BMP每毫克的活性超过四倍。然而，考虑到两个系列缺损自发愈合的差异，异种BMP（5.7±1.7）和同种异体BMP（9.05±3.7）之间仅显示出轻微但不显著的活性差异（P = 0.077）。
该结果与先前发表的结果一致，表明在原位单次植入异种BMP后未观察到明显的免疫抑制。
