ABSTRACT
Objective To investigate the effects of bone mesenchymal stem cells (BMSCs)transplantation on the neurological function recovery of injured spinal cord and the underlying mechanism.Methods Rats were subjected to contusive spinal cord injury by using NYU spinal cord contusive impactor system ( NYC lmpactor).Seven days after spinal cord injury,the transplantation of BMSCs ( BMSCs group) or injection of PBS ( PBS group) was performed around the epicenter of injured spinal cord in rats.Basso-Beattie-Bresnahan (BBB) score was used to evaluate the function of spinal cord.The cavity volume of the injured spinal cord was measured and the axons in the injury center of spinal cord were examined under transmission electron microscopy.The BMSCs of the green fluorescent protein (GFP)transgenic rats were used to trace the transplanted cells and the survivor of BMSCs in the injured spinal cord and their differentiation into neural cells were observed.A mini-channel implantation model was employed to further investigate the role of BMSCs transplantation on the axonal regeneration.Results The BMSCs group showed a higher BBB score and a smaller lesion volume as compared with the PBS group.Transmission electron microscopy examination displayed that the number of axons in the BMSCs group was far more than that in the PBS group.A great number of BMSCs-GFP were founded around the center of the injured spinal cord at 4 weeks after BMSCs transplantation.lmmunohistochemistry showed that the implanted BMSCs-GFP did not express the surface marker of neurons,astrocytes and oligodendrocytes.In the mini-channel implantation model,NF-positive nerve fibers grew into the BMSCs-seeded channel,while there were no nerve fibers in the channel without seeding of BMSCs.Conclusions The BMSCs transplantation for the injured spinal cord promotes its functional recovery,and the related mechanism is in correlation with BMSCs transplantation inducing axonal regeneration.
ABSTRACT
Objective To investigate T cell receptor(TCR)variable β(BV)chain usage at the maternal-fetal interface and explore the relationship between the skewed TCR BV usage and unexplained recurrent spontaneous abortion(BSA).Methods Eighteen cases with unexplained RSA,together with matched 41 women with normal pregnancies in first trimester from Renji Hospital,Shanghai Jiao Tong University were studied.A high-resolution spectrum typing analysis of complementarity-determining region 3 (CDR3)was used to detect and compare the degree and frequency of TCR BV family expression in deciduas between RSA patients and normal controls.Results(1)The expression degree of BV19(0.029±0.031 vs.0.013±0.010,P=0.038)in RSA group showed a higher usage,while BV5.2(0.040±0.035 vs.0.067±0.052,P=0.046)showed a significantly lower usage when compared with normal controls.No significant difference in the expression of the other TCR BV families between RSA and controls were observed(P>0.05).(2),TCR BV2,3,6,and 7 were the four most common BV families in deciduas of patients with RSA and normal controls,whose frequencies were all mors than 50%.In RSA group,higher frequencies of BV15 (33.3%vs.7.3%,P=0.018),BV19(38.9%vs.14.6%,P=0.049)and BV20(33.3%vs.7.3%,P=0.018)were observed;meanuhile lower frequencies of BV4(33.3%vs.65.9%,P=0.026)and BV7 (66.7%vs.92.7%.P=0.018)distributions were observed.The other TCR BV families did not display significantly different freqencies of distribution(P>0.05).Conclusions It is suggested that a significant skewed TCR BV family occurs at the maternal-fetal interface in patients who undergo abortion.The specific skewed usages of TCR BV might be associated with the susceptibility to unexplained pregnancy loss.