异种角膜基质异位植入后免疫病理学研究

Immunopathologic study on fresh and dehydrated xenografts in porcine-to-mouse model of corneal stroma hetertopic xenotransplantation

目的观察异种角膜基质异位植入后的免疫病理变化,评价其免疫相容性。方法将一定大小的新鲜的和甘油脱水的猪角膜基质植入到小鼠皮下组织内,同时以异种皮肤、假手术为阳性和阴性对照;术后1个月取材进行组织病理学观察,并通过免疫荧光细胞化学法检测植入材料内T淋巴细胞总数和亚群的变化。结果新鲜的和甘油脱水的猪角膜基质皮下植入后1个月,可见少量的淋巴细胞、巨噬细胞、CD3+细胞、CD4+细胞、CD8+细胞浸润,且CD4+细胞多于CD8+细胞,但未达到阳性对照水平(P<0.05)。结论异种角膜基质异位植入后早期局部未引发免疫排斥反应,免疫相容性好。

Objective To observe the immunopathologic alterations of the fresh and dehydrated xenografts in a porcine-to-mouse model of corneal stroma hetertopic xenotransplantation and assess its immunocompatibility. Methods Twenty-four mice were randomly divided into 4 groups. The fresh and dehydrated corneal stroma from porcine corneas were subcutaneously implanted into the mice of experimental groups,and xenogeneic dermas implantation mice and sham operation mice served as positive control and negative control group,respectively. Grafted corneal stroma was excised 30 days after grafting for histopathologic study,and the changes of total T lymphocyte and its subset counts in the xenografts were observed using the direct immunofluoresecent technique. Results No edema and ulceration were seen in the graft area in experiment groups 1 month after surgery by clinical observation. A small quantities of lymphocyte,macrophages,CD3（＋） T cells,CD4（＋） T cells and CD8（＋） T cells infiltrated into both of the fresh and dehydrated xenografts at month 1 in postimplantation, but number of infiltrated cells（79.00±9.78 in fresh xenograft group,and 71.83±9.54 in dehydrated xenograft group）was less than that of xenogeneic dermas group（ 134. 50±19.71 ） （P 〈 0. 05）. No granuloma-like structures were found in the fresh and dehydrated xenografts,similar to xenogeneic derrnas. There were significant intergroup differences in the CD4 ＋ /CD8 ＋ ratio between the xenogeneic corneal stroma and the xenogeneic dermas （ P 〈 0. 05）. Conclusion Immunological rejection does not occur at the early stage in a porcine-to-mouse model of corneal stroma hetertopic xenotransplantation,indicating that xenogeneic corneal stroma has better immunocompatibility.