文档介绍：高群体反应性抗体的血液净化Purification In Highly Sensitized Renal Transplant Recipients
器官移植中心血透室
The Dialysis Center，Hunan Organ Transplantation Academy
目前常用的组织配型方法 Main tissue matching methods
1. ABO血型:ＡＢＯ血型基因型只有6种基因而随机人群中容易获得配合.
2. CDC试验:检测患者体内针对供者ＨＬＡ特定位点的抗体.
:检测患者体内针对同种HLA抗原的抗体.
:理想的ＨＬＡ配型,尤其ＤＲ位点相配可使存活率提高10%～30%,对再次移植和高危患者效果更明显，具有10亿个基因型高度多态性的ＨＬＡ成为选择配合移植的主要难题。
Main tissue matching methods include ABO blood type crossmatch, CDC (complement-dependent-cytotoxicity) test, PRA(panel reactive antibody) detection and HLA (human leukocyte antigen)typing. HLA-A,B,DR locus especially DR locus well matched will improve the survival rate for 10-30% while it is very difficult to do so in practice.
ＰＲＡ的检测原理 The principle of PRA test
利用已知抗原的淋巴细胞与未知血清及补体孵育,如患者血清中含有与淋巴细胞表面特异结合的抗体,在补体存在的情况下,可发生细胞溶解作用,根据细胞溶解程度判断患者的免疫状态及HLA抗体的特异性。
The principle of PRA test is that the lymphocytes whose antigens were known were incubated with complements and patients’ sera together, then we can judge these patients' immune status and the specificity of HLA antibodies according to the degree of cytolysis.
ＰＲＡ的产生原因 Why did the PRAs produce?
ＨＬＡ抗体产生绝大多数由移植前输血、妊娠和再次移植所致,极少数可能是由某些病毒或细菌的分解物所携有的类似ＨＬＡ抗原所致。初次移植病人ＰＲＡ阳性率有明显性别差异,男∶女=8∶36. 6,有两种或多重致敏经历的病人通常ＰＲＡ峰值高居不降。
Preformed circulating cytotoxic IgG anti-HLA alloantibodies induced by previous failed grafts, blood transfusion, pregnancy or infection are a relative contraindication to allotransplantation and apt to result in hyperacute rejection.
其他因素:(1)受者ＨＬＡ A1或 Ａ2表型者易致敏;(2)黑人受者普遍高ＰＲＡ,且接受黑人移植物比接受白人或黄种人移植物的排斥率高;(3)长时间的血液透析。
(1) CDC test revealed that A1 and A2 antigens were highly immunogenic;（2）The black race commonly has high PRA；（3）Undergoing the hemodialysis for long time.
ＰＲＡ的分类 Classify the PRA
高ＰＲＡ所针对的免疫原可以是ＨＬＡ抗原,也可以是非ＨＬＡ成份,抗HLA 类抗原的抗体,包括IgG1～4、IgM和IgA,引起超急性排斥反应的主要是IgG1类抗体, %,而IgG2～4及IgM的预测值为0。IgA的有益作用机制可能为阻断IgG及补体介导。
PRA mainly aim directly at HLA which comprise IgG1～4、IgM and IgA. Only