Analysis of mechanisms in delayed xenograft and cellular rejection in xenotransplant between human and swine

通过给药人外周血淋巴细胞（PBL）建立了具有人免疫环境的人源化严重联合免疫缺陷小鼠（SCID）。这种hu-PBL-SCID小鼠也被证明在其循环中涉及功能性人类淋巴细胞和免疫球蛋白。为了显示猪移植物与人在小鼠体内的真实异种移植情况，采用猪肠系膜动脉直接搭桥法对hu-PBL-SCID进行腹主动脉搭桥。对恢复的异种移植物进行分析，发现人IgM黏附于内缘，淋巴细胞侵袭内皮。通过免疫吸收阻断异种反应性血清学反应，病理分析显示这些淋巴细胞属于人CD3+CD4+。接下来，我们试图通过改变异种移植恢复时间来确定在最严重情况下观察细胞排斥反应的最佳时间。建立稳定的细胞排斥模型。然而，由于个体间的差异，很难确定。人淋巴细胞在猪动脉异种移植物的侵袭中未被检测到。以辐照猪主动脉内皮细胞（PAEC）为刺激剂，以辐照人原始淋巴细胞为喂料剂，将这种异种移植物恢复到组织培养中，试图在体外构建人异种反应细胞系。然而，由于移植物的污染，实验结果是不可能的。最近，我们的一位同事Dr.Sasaki发现人类NK细胞在异种移植物中识别HLA-G和E基因的不表达，并在异种移植物排斥反应中发挥作用（Transplantation 67; 31-37 1999）。我们试图在体内系统中使用hu-PBL-SCID小鼠模型来证明这一证据。从hu-PBL-SCID小鼠体内回收了转染HLA-G和E基因的猪肝异种供体，但本实验未发现异种反应抑制作用。我们的一份包含这些结果的手稿现在已经出版了。少

Humanized severe combined immunodeficient (SCID) mice, which exhibited human immunological environment, were established by administration of human peripheral blood lymphocytes (PBL). This hu-PBL-SCID mice were also demonstrated to involve functional human lymphocyte and immunoglobulin in their circulation. To display the real xenotransplant circumstances from swine graft to human in mouse, swine mesenteric arterior was applied for direct bypass of abdominal aorta in hu-PBL-SCID. Analysis of recovered xenograft revealed human IgM adherence to inner rim and lymphocytes invasion on the endothelium of the xenograft. By blocking the xenoreactive serological response with immuno-absorption, pathological analysis indicated these lymphocytes belonged to human CD3+CD4+ in staining. Next, we tried to determine the optimal time to see the cellular rejection in the severest condition by changing the recovering time of xenograft. Stable model of the cellular rejection were.however, difficult to es … More tablish due to the interindividual differences. Human lymphocytes were unable to be detected in the invasion into swine arterior xenografts. We also tried to contitute the human xenoreactive cell line in vitro by recovering this xenografts to tissue culture using irradiated pig aortic endothlial cell (PAEC) as stimulator and irradiated original human lymphocytes as feeder. This experiment, however, resulted in impossible condition due to contaminations from grafts.Recently Dr.Sasaki, one of our colleagues, showed that human NK cells recognized non-expression of HLA-G ＆ E gene in xenograft and played a role in xenograft rejection (Transplantation 67; 31-37 1999). We tried to indicate this evidence in in vivo system using hu-PBL-SCID mice model. Swine arterior xenogarfts transfected with HLA-G ＆ E gene were recovered from hu-PBL-SCID mice, but no suppressive effect of xenoreactive responses were noted in this experoment. One of our manuscripts containing these results were now (in press). Less