MRI tracking of superparamagnetic iron oxide-labeled rabbit bone marrow mesenchymal stem cells for treatment of femoral head avascular necrosis / 中国组织工程研究

ABSTRACT

BACKGROUND:Bone marrow mesenchymal stem cell(BMSC) transplantation is one of the developmental directions in the treatment of femoral head necrosis. In recent years, the use of superparamagnetic iron oxide (SPIO) nanoparticles labeled target cells traced by MRI imaging method has become the focus of the study. OBJECTIVE:To observe the in vivo MRI tracking and the curative effects of SPIO-labeled BMSC transplantation on rabbit femoral head necrosis. METHODS:SPIO-labeled BMSCs, unlabeled BMSCs, and normal saline were injected in situ into the necrotic femoral head of rabbits. Fol owing MRI dectection, the image changes of transplanted BMSCs marked by SPIO were observed among the three scanning sequences of SE T2WI, FSE T2WI and GRE T2*WI. Meanwhile, the area percentage of newly formed bone trabecula in the defect samples under high power lens were observed and calculated for statistical analysis. RESULTS AND CONCLUSION:In situ celltransplantation group showed the emerging and extinctive time of the decreased-signal region was different among the three scanning sequences of SE T2WI, FSE T2WI and GRE T2*WI. It was found that the decreased-signal region of the MRI scanning sequences was the target of the present experiment. No obvious signal change occurred in the control side. After 6 weeks of transplantation, the area percentage of newly formed bone trabecula in the defect samples showed no difference in SPIO-labeled and unlabeled BMSC transplantation groups (P>0.05), but it was higher than that in the control side (P<0.01). The SPIO-labeled BMSCs and unlabeled BMSCs are shown to have the same effects in the treatment of femoral head necrosis. The SPIO-labeled BMSCs can be observed obviously by MRI detection in vitro.