| Objective Osteoblast of the same venter -, allostrip > heterogeneity and autogeneity marked by GFP were transplanted into the rectus abdominus muscle of the each rabbit.Detect the cellular immunity and humoral immunity of different stirps osteoblast transplantation,and to discuss the potential immunological mechanism.Try to find the reliabal cell source of tissue-engineered-bone by the transplantation physiology and phylogeny.Methods (1) Primary culture and GFP mark of osteoblast: osteoblast were harvested from limbs of 5 ages rasbits and 3 days SD mice,The cells were enzymatically separated and grown in culture to increase their number. The cells wre then transfected with lipofectamine and pIRES2-EGFP. (2)Animal groups and cell transplant: rabit were separated into five groups: allotransplantation (groupA), same-venter transplantation(groupB), heterotransplantation(groupC) injected by SD rat osteoblasts and autotransplantation(groupD) injected by chondrocytes of self auricles.All cells were implanted into the abdominal wall. (3) Immunity and histopathology assay:the serum antibody were detected by ELISA.The cellular immunity were detected by LTT assay.The CMC medied by T cells were detected byMTT assay.The histologic preparations were then examined under a fluorescent microscope to demonstrate the presence of transplanted cells.Then to examined the local reaction against the implantation by HE staining.Results (Dserum antibody detected:A specifc antibody reaction were detected in all groups one or two weeks after transplantation,and heterogeneity group persisted the longest time and had the highest value than otheer groups.(2)little effects were found in group B and D after PHA stimulating. A cell mediated cytotoxicity and rising cellular immunity were detected in allostrip and heterogeneity groups two weeks after transplantation and touch the peak value 4 weeks later,the value of heterogeneity group was higher than allostrip group. (3) Low-grade inflammatory reaction appeared in the injected muscle of all groups Iweek later and became intensive 2 weeks later.4weeks after transplantation,the reaction began to decrease and no implants were detected in groupC.Cells of group A> B> D remained viable and were detectable 8 weeks following transplantation when examined histologically and observed under a fluorescent microscope.Bone formation in vivo were detected in same venter groups 8 weeks later.Conclusion The modified osteoblast primat culture combine digestion with specimen,and can release a large amount of pure osteoblasts in a short period. It adapts to tissue restructure by tissue-engineering skills.Cell marked by fluorescence has been used in many studies ,but the GFP has been used just since 1996.This study built an GFP marked osteoblast line by lipid enwarping and improved the osteoblast transplantation model built by Peter in 1998. Use this model, we detected the immunity reaction and growth in vivo of different source cells transplantation.The gene superposition rate of same venter animals are similar to syngenic animals.So the MHC character between same venter animals are similar,and the immunological reactions are also weak.Allotransplantation is the emphases of this study.lt can arose a increase in humour and cellular immunity reaction,obviousest in four to eight weeks and alive in host eight weeks later.This show that the osteoblast allotransplantation can not be excluded by host and has a abroad use value. By research of xenotransplantation of organs,a transplant between similar genes had a immunological reactions midied by lymphocytes,and stronger than allotransp -lantation. But the reactions in osteoblasts transplantation were much lower than bone transpantation.Becouse bone had many different kinds of cells which had type n MHC on surface and nature xeno-antigen.And osteoblast can only express I MHC. To conclude,reconstructing bone by tissue-engineering way is practical under transplantation immunology.Same venter and autogeneity cells can be the reliable cell source for ti...
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