混合植皮中自体皮岛免疫抑制效应和间接识别机理的关系初探

本文建立烧伤患者淋巴细胞与异体表皮细胞的混合培养体系（ＭＥＬＣ），并进一步添加自体表皮层细胞，以模拟混合皮肤移植时自体皮岛的局部微环境，探讨相应的免疫学机理。结果发现：１．自体表皮层细胞能有效地抑制ＭＥＬＣ反应；２．抗原加工阻断剂预处理自体表皮细胞之后，后者对自身淋巴细胞的增殖抑制现象消失或明显缓解，提示自体表皮层细胞有抗原递呈功能，参与对同种异体抗原的间接识别；３．单抗封闭实验显示ＤＲ分子不参与自体表皮的抗原递呈作用。据推测ＤＱ等非ＤＲ分子可能参与自体表皮对异体ＨＬＡ抗原的加工递呈。相应的免疫机制，有待进一步探讨。

Exploration for Mechanism with Regard to the Immunological Effect of Autologous Skin lslet on the Intermingled Skin Grafting: A Model for Indirect Recognition of Alloantigens

To explore the immunological mechanism of the autoskin islet-induced effect, a primary mixed cuture system using burned patients'PBL and alloepidermal cells (MELR) was set up in this study as an in vitro microenvironment to mimic the intermingled skin grafting in case extra auto-epidermal cells (AECs) were superimposed. It was found that: 1)The AECs was able to work in the MELR as a down regulator to induce an hypo-lymphoproliferation. 2) The depresscd response of lymphocytes could be recovered by pre-pulsing AECs with chloroquine, an potent inhibitor of antigen procession in antigen presenting cells. This indicated that the homunosuppression exerted by the AECs might be resulted from their ability of procession and presentation of HLA molecules shed from alloepidermal cells, a phenomenon refered to as indirect recognition of alloantigen by T lymphocytes. 3) Tested by blocking assay with mAb, HLA-DR antigen was shown irrelevant to AECs down regulatory property. Whether involved was Do, a different kind of class 11 HLA molecule which is more tightly connected with immunosuppression, would be of special interest and of value for further investigation.