In vivo study of human xenogeneic immune system by SCID mice GVHD model

利用严重联合免疫缺陷（SCID）小鼠的免疫缺陷性，将异种免疫系统导入SCID小鼠体内，建立了移植物抗宿主病（GVHD）动物模型，用于检测移植的人外周血白细胞（PBL）的体内功能。人PBL的转移已经成功或产生急性GVHD，然而，关于人PBL发展GVHD的经典症状的能力的争议仍然存在。用全身照射（250 R）抗淋巴细胞血清（ALS）和抗去唾液酸GM 1的组合预处理SCID小鼠，（抗小鼠自然杀伤细胞）抗血清，然后腹膜内注射1 × 10（6）人PBL。人CD_3阳性细胞在外周血中为1.66-3.36%，在脾脏中为2.27-3.67%。将人肿瘤细胞系皮下或腹膜内植入SCID小鼠以估计摄取率。SCID小鼠的总摄取率为0%。在我们的实验中，CB-17/Icr-scid Jcl不能接受任何人细胞和细胞系。经放射线和血清处理后，携带人细胞的小鼠2周死亡率为60%（3/5），而对照小鼠为100%。SCID小鼠肺、肝、十二指肠淋巴细胞植入的组织学检查与正常对照组无明显区别。尽管我们未能建立SCID小鼠GVHD模型，但我们改进了细胞免疫选择方法，使其能够快速阳性选择存活的T、B淋巴细胞。

The use of severe combined immunodeficient (SCID) mice to examine ways to introduce a xenogeneic immune system into SCID mice by taking advantage of the immune deficiency of the mice has provided an animal graft-versus-host disease (GVHD) model to examine the in vivo fanction of transferred human peripheral blood leukocytes (PBL). Transfer of human PBL has been successful or produced acute GVHD,however, the cotroversy remains regarding the capability of human PBL to develop classical symptoms of GVHD.To obtain consistent engraftment with GVHD,SCID mice were pretreated with a combination of total body irradiation (250R) anti-lymphcyte serum (ALS) and anti-asialo GM1 (anti-mouse natural killer cell) antiserum before the intraperitoneal injection of 1 X 10 (6) human PBL.With this protocol, human CD3-positive cells was 1.66-3.36% in the peripheral blood and 2.27-3.67% in the spleen. Human tumor cell lines were implanted subcutaneously or intraperitonealy into the SCID mice to estimate the take rate. The overall take rate was 0% for SCID mice. In our experiment, CB-17/Icr-scid Jcl could not accept any human cells and lines. Mortality at 2 week was 60% (3/5) in the mice bearing human cells after the treatment of irradiation and serum compared with 100% in the control mice. Histologic examination of lymphocytes engraftment of lung liver and duodenum was indistinguishable from normal control in SCID mice. In this context, the cause of death in SCID mice was thought to be the toxic effect of pretreatment rather than GVHD.Although we could not established a GVHD model with SCID mice, we have modified the method of immunoselection of cells which allows a fast positive selection viable T,B lymphocytes.