人T细胞对猪白细胞抗原的直接识别

猪已被认为是异种移植的最理想供体。有关人 猪器官间超急性排斥研究已有所突破 ,而细胞性排斥报道尚少。本文用混合淋巴细胞反应体系研究异种移植细胞性排斥机制 ,发现异种反应明显弱于同种反应 ,而且以直接识别为主 ,这和同种移植细胞性排斥机制一致。抗人CD4单抗和抗猪白细胞抗原SLA DR、DQ单抗都能明显地抑制 (XMLR) ,而抗人CD8单抗无抑制功能 ,表明CD4+T细胞对SLA的识别在异种排斥应答中起重要作用

Human T Cell Responses to Swine Leukocyte Antigens Through Direct Recognition

The progress in overcoming hyperacute rejection in xenotransplantation by modification of swine organ with transgeneic DAF gene has pushed the exploration with regard to mechanisms underlying the followup cellular rejection to the frontier in transplantation immunology In this study,the irradiated peripheral blood mononuclear cells (PBMCs) or purified T cells of a Chinese miniswine,Guangxi pig, were adopted to establish an oneway xenoMLR with human T cells or PBMCs as responding cells As indicated in our data,the intensity of the xenoreaction was much weaker (cpm 876714573) as compared with that of alloreaction (2826029579) In the experiments with purified T cells,it has been shown that in the oneway xenoMLR,the patterns of T cell proliferation were quite different when accessory cells (ACs) from recipients (human) or donors (Guangxi pig) had been introduced respectively In case swine ACs were included,the cpm value in the xenoMLR was round 14544 If ACs came from recipient,however,cpm value could be dropped down to less than 1145 The results implicated there was a predominance of direct recognition and presentation of xenoantigen in our MLR experiment system In addition,mAbblocking experiments indicated that the majority of primary human antipig response was connected with SLADR and DQ antigens Since human CD8 positive T cells seemed not active in the xenorecognition,the human CD4 T cells,especially those expressing HLADQ molecule,was identified critical component in our xenogeneic MLR in vitro