无细胞异种真皮基质临床应用的免疫反应特征

The characteristics of immune response on acellular xenograft dermal matrix in clinical application

目的 探讨临床应用异种猪 /异体人无细胞真皮基质 (s /h ADM )的免疫反应特征。方法 在临床大面积烧伤患者深度切痂创面上 ,将s ADM或h ADM与超薄断层自体皮重叠移植 ,采用免疫组化和原位杂交方法检测移植物中CD3、CD4、CD8、γ 干扰素 (IFN γ)和白细胞介素 4 (IL 4 )阳性细胞的百分比 (% ) ,以及IFN γ和IL 4mRNA的表达水平。结果 浸润于ADM组织中免疫细胞以CD4和IL 4阳性细胞为主 ,与免疫组化结果一致 ,IL 4mRNA在所有标本中均有较高的表达水平 ,s ADM组表达显著强于h ADM组 (P <0 0 5 ) ,在发生排异反应前的s ADM组织中IL 4mRNA和IFN γmRNA一样阳性细胞均明显增加 ,而排异后两者均显著下降 ;IFN γmRNA仅在h ADM组移植早期有弱阳性表达 ,与s ADM组统计学有显著性差异 (P <0 0 5 ) ,接近于断层中厚自体皮片移植物。结论 s ADM移植后的免疫应答是由异种组织特异性蛋白引发的Th2淋巴细胞介导的体液免疫过程。

Objective To investigate the characteristics of immunological response after clinical cografts of acellular xenogeneic(swine)dermal matrix(s-ADM)or allogeneic(humans)dermal matrix(h-ADM).Methods On the wound of eschar excision wounds of severe burn patients of large area burns,s-ADM or h-ADM were overlapped and grafted with ultrathin split thickness skin autografts(USTS),and then,the immunohistochemistry and in situ hybridization methods were used to detect the percentages(%) of CD3,CD4,CD8,IFN-γ and IL-4 positive cells,and the expression levels and significance of mRNA of IL-4 and IFN-γ.Results In immune cells with all ADM group,the number of positive cells of CD4 and IL-4 increased significantly(P<0.05～0.001).In all groups,the mRNA of IL-4 had higher expression level,and the expression levels of s-ADM group was apparently higher than those of h-ADM group(P<0.05).In s-ADM group before rejection the number of positive cells of IFN-γ mRNA and IL-4 mRNA increased significantly,and after rejection the expression levels of both were apparently decreased(P<0.05).The mRNA of IFN-γ had weak positive expression only in h-ADM group in the earlier phase,and were significantly different with that of s-ADM group(P<0.05),but that was similar with split-thickness skin autografts.Conclusion The immune response was a humoral immunity process guided by a specific xenogeneic protein,and mediated by Th2 lymphocyte after s-ADM transplantation in clinical application.