PRA的血液净化.pptx

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检测的意义 (The sense for PRA test）
反映受者人类白细胞抗原体液致敏状态,ＰＲＡ增高，移植后导致急性、超急性、加速排斥反应和肾功能延迟，移植前ＰＲＡ水平的峰值比在手术时检测ＰＲＡ更能预测移植物存活的结果。高ＰＲＡ受者的抗体为ＩｇＧ性质,或曾经出现高峰值ＰＲＡ,近期ＰＲＡ自然或人为干预下降,其诱导排斥反应的作用仍然存在,术后超急、加速排斥率均比ＰＲＡ阴性高80%。
The test result of PRA can affect recipient’ sensitivity status of humoral immunity. It was proved that high PRA pretransplantation can lead to episodes of acute, hyperacute, accelerated rejection of renal allografts or delayed renal graft function.
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 IgG1 antibodies account for hyperacute and accelerated rejection. IgG2～4 and IgM class antibodies are not associated with posttransplant rejection. furthermore, IgA does good to rejection reaction by its blockage to complements and IgG .
PRA的分度Grading of PRA
据PR