抗CD20单克隆抗体在预防小鼠皮肤移植急性体液性排异反应中的作用

发布时间：2018-07-09 23:20

本文选题：抗CD20单克隆抗体 + B淋巴细胞　；参考：《吉林大学》2012年硕士论文

【摘要】：目的：本实验探讨抗CD20单克隆抗体在小鼠皮肤移植模型中如何预防急性体液性排异反应。目前研究证实，T淋巴细胞在急性体液性排异反应中起主导作用，而B淋巴细胞及其成熟浆细胞产生的抗体参与了体液性排异反应的发生。由于免疫抑制剂高效性和临床应用的广泛性，使同种异体肾移植进步显著，移植物总体存活时间明显延长，排斥总体发生率明显降低。然而，目前临床上常规使用的抗增殖类药物、钙神经蛋白抑制剂及激素主要针对于T淋巴细胞介导的细胞免疫，对体液性免疫抑制作用远低于对细胞免疫抑制作用[1]。目前应用于临床的针对B淋巴细胞的药物较少，如何清除B淋巴细胞，抑制B淋巴细胞在体液性排异反应中发挥的作用，成为国内外移植中心研究的热点。由B淋巴细胞产生的作为参与体液性排异反应的供体特异性抗体（donor-specific alloantibodies，DSA）将供者的上皮细胞作为攻击的靶点[2]，产生抗体介导的体液性排异反应。因此清除受者体内的B淋巴细胞、抗体及DSA成为预防及治疗抗体介导的体液性排异反应的焦点。随着对B淋巴细胞及其作用机制的深入研究证实，CD20抗原分子是表达于前B淋巴细胞及成熟B淋巴细胞表面的跨膜糖蛋白，是参与B淋巴细胞活化以及抗原识别的主要分子。抗CD20单克隆抗体与B淋巴细胞表面的CD20分子有较高的亲和力，可通过诱导细胞凋亡作用、抗体依赖的细胞介导的细胞毒作用及补体介导的细胞毒作用杀伤B淋巴细胞。因此，CD20单克隆抗体是一类具有独特生物学作用的生物制剂，在移植抗体介导的体液性排异治疗中扮演着重要的角色。方法：一组受鼠给予供体脾脏细胞悬液腹腔注射，后提取血清经鼠尾静脉注射法注射到另一只受鼠体内；另一组给予抗CD20单克隆抗体鼠尾静脉注射。然后建立皮肤移植及血管组织皮下包埋模型，术后观察移植皮肤存活状况。应用流式细胞技术检测鼠尾静脉注射抗CD20单克隆抗体小鼠B淋巴细胞，并切取移植皮肤及血管组织行组织病理学检查，进一步研究抗CD20单克隆抗体在抗体介导的体液性排异反应中的作用。结果：（1）对照组小鼠移植皮片平均存活时间（MST）为11.5天，鼠尾静脉注射血清组的皮片平均存活时间为9天，鼠尾静脉注射抗CD20单克隆抗体组的皮片平均存活时间为12.5天。（2）流式细胞技术检测鼠尾静脉注射抗CD20单克隆抗体组脾细胞中B淋巴细胞（B220+）的百分比。与正常小鼠比较，，鼠尾静脉注射抗CD20单克隆抗体组B淋巴细胞显著减少，P0.05。（3）取3组脾脏组织行HE染色病理学检查。鼠尾静脉注射血清组较对照组脾脏组织中生发中心明显增大，淋巴细胞密集；鼠尾静脉注射抗CD20单克隆抗体组较对照组脾小体明显缩小，淋巴细胞明显减少。（4）取受体鼠移植皮片及血管组织行HE染色病理学检查。鼠尾静脉注射血清组较对照组移植皮片组织和皮下包埋血管组织炎细胞及淋巴细胞浸润明显增多，组织结构破坏明显。血管组织炎症反应重，部分血管壁机化，血管各层组织破坏严重，管腔堵塞。鼠尾静脉注射抗CD20单克隆抗体组移植皮片组织和皮下包埋血管组织炎细胞及淋巴细胞浸润明显少于对照组，组织结构破坏不明显。血管组织炎症反应轻，血管各层组较完整，管腔存在。结论：通过鼠尾静脉注射抗CD20单克隆抗体组小鼠移植皮片生存时间延长，术前使用抗CD20单克隆抗体能有效预防抗体介导的急性排异反应的发生。
[Abstract]:Objective : To investigate the effect of anti - CD20 monoclonal antibody on the prevention of acute humoral rejection in mouse skin transplantation model . B - lymphocytes , antibodies and DSA are the main targets for the prevention and treatment of antibody - mediated humoral rejection . As a result , the CD20 monoclonal antibody is a kind of biological agent with unique biological effect , which plays an important role in the humoral rejection therapy mediated by transplantation antibody .

Methods : A group of mice were injected intraperitoneally with the donor spleen cell suspension , and the serum was injected into the other mice via the tail vein injection method .
The effect of anti - CD20 monoclonal antibody on antibody - mediated humoral rejection was investigated .

Results :

( 1 ) The average survival time ( MST ) was 11.5 days in the control group , and the average survival time was 9 days after the tail vein injection . The average survival time of the anti - CD20 monoclonal antibody group was 12.5 days .

( 2 ) The percentage of B lymphocytes ( B220 + ) was detected by flow cytometry in the spleen cells of mouse tail vein anti - CD20 monoclonal antibody group . Compared with normal mice , the anti - CD20 monoclonal antibody group B lymphocytes were significantly decreased in mice tail vein , P0.05 .

( 3 ) HE staining was performed in three groups of spleen tissues .
Compared with control group , the anti - CD20 monoclonal antibody group was significantly reduced in mice tail vein , and the lymphocytes decreased significantly .

( 4 ) HE staining was performed on the skin graft and vascular tissue of the recipient mice . The tissue structure was damaged . The inflammatory response , partial vessel wall movement , tissue destruction in the vascular tissues were significantly smaller than those in the control group . The tissue structure was not clear . The inflammatory reaction of the vascular tissue was mild , the vessel layers were intact , and the lumen was present .

Conclusion : Anti - CD20 monoclonal antibody can be used to prevent antibody - mediated acute rejection by intravenous injection of anti - CD20 monoclonal antibody .
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R392.4

【参考文献】