肾移植患者长期存活与MICA抗体相关性研究

Correlation between long term survival and MICA antibody level in patients with renal transplantation

目的探讨肾移植术后长期存活和肾功能正常患者与组织相容性复合物Ⅰ类链相关基因A(AMICA)抗体的关系。方法追踪1992年至2004年间在我院接受尸体肾移植的48例患者,采用MICA抗体流式筛查技术检测其近期(2009年7月)MICA抗体,在此期间其群体反应性抗体(PRA)均为阴性,且血肌酐和尿素氮均正常。此48例患者目前人/肾存活最长已达17年,最短也达5年以上。结果 48例肾移植术后PRA阴性、血肌酐和尿素氮均基本正常的患者中有12例MICA阳性,阳性率25%。其中9例患者呈现多价抗体阳性。MICA抗体呈规律性阳性,其中有6例表现为MICAG1同时阳性(MICA001,MICA 002,MICA 007,MICA 012,MICA 017,MICA 018),3例表现为MICAG2同时阳性(MICA 004,MICA 006,MICA 008,MICA009,MICA19),另外3例表现为MICA017单价抗体阳性。48例肾移植术后有36例MICA抗体阴性患者,经过1年左右的观察发现,6例患者移植肾功能呈逐渐下降趋势。12例MICA抗体阳性患者,有3例移植肾功能急速下降,1年后恢复透析。结论 MICA抗体对移植肾功能的改变及存活率的影响还有待进一步研究。

Objective To study the relationship between long term survival and level of MICA antibody in patients with renal transplantation.Methods Levels of MICA antibody in 48 patients received cadaveric renal transplantation during 1992 to 2004 were examined by using flowing antibody screening technique（with Luminex100,MICA AbScan Kit） in July,2009.Furthermore,their examination for PRA antibody showed negative,and serum levels of creatinine and urea nitrogen were normal.Allografts in these 48 recipients could survive as long as 5 to 17 years.Results Examination of MICA antibody in 12 of these 48 recipients with negative PRA and normal serum levels of creatinine and urea nitrogen showed positive result（12/48,25%）,and 9 of them showed positive multivalent antibody of MICA.Among them,6 patients showed positive MICA001,MICA 002,MICA 007,MICA 012,MICA 017 and MICA 018 antibodies,and 3 of them showed positive MICA 004,MICA 006,MICA 008 and MICA009 antibodies,and the remaining 3 patients showed positive MICA017 antibody.After the transplantation,36 of 48 patients showed negative level of MICA antibody,and 12 patients showed positive result.After follow-up for one year,the function of graft in 6 recipients of these 36 patients with negative MICA antibody was gradually deteriorated;and the graft function of 3 recipients in 12 patients with positive MICA antibody was sharply deteriorated in one year later,and renal dialysis was regained.Conclusion Further studies are needed in order to observe the influence of MICA antibody on allograft function and long term survival rate.