广州管圆线虫幼虫排泄分泌抗原及其诊断价值分析  

Analysis of larval excretory-secretory antigen and its immunodiagnosis of Angiostrongyliasis cantonensis infection

作　　者：张鑫[1] 刘敏[1] 吴雅欣[1] 莫泽珣[1] 沈浩贤[2] 陈代雄[2] 李华[1] 

机构地区：[1]南方医科大学公共卫生与热带医学学院病原生物学系,广东广州510515 [2]广州医学院病原生物学教研室,广东广州510182

出　　处：《南方医科大学学报》2012年第4期477-481,共5页Journal of Southern Medical University

基　　金：国家自然科学基金(30972577);广东省自然科学基金(9151051501000073)~~

摘　　要：目的对比分析广州管圆线虫幼虫排泄分泌抗原(LESA)与成虫抗原(AWA),探讨其诊断价值。方法广州管圆线虫三期幼虫感染小鼠,21 d后取小鼠脑内幼虫进行体外培养,收集幼虫排泄分泌蛋白,并与广州管圆线虫成虫匀浆蛋白进行SDS-PAGE和Western blot分析,分别用两种抗原建立LESA-ELISA和AWA-ELISA以检测小鼠血清和不同人群血清。结果SDS-PAGE和Western blot显示幼虫排泄分泌蛋白条带和抗原反应带较成虫少;LESA与小鼠感染血清和广州管圆线虫病患者血清在Mr40 000和Mr26 000处均出现强反应带;感染小鼠血清中抗LESA和AWA的IgG和IgM抗体自感染后开始上升,5 d后达到高峰,第10天后开始下降;LESA-ELISA用于检测广州管圆线虫病疑似病人血清阳性率低于AWA-ELISA;检测血吸虫和华支睾吸虫感染病人血清的交叉阳性率明显低于AWA-ELISA;检测献血员血清及其他非广州管圆线虫感染血清时,假阳性数较AWA-ELISA少。结论 LESA的抗原反应带较AWA少,尽管对广州管圆线虫病疑似病例血清抗体阳性率略低于AWA,但其特异性高;具有潜在的广州管圆线虫病早期诊断和现症感染诊断价值。Objective To analyze the diagnostic value of larval excretory-secretory antigen in Angiostrongylus cantonensis（LESA） infection.Method A.cantonensis larvae harvested from mice brain were cultured in vitro.The LESA and the adult worm antigens of A.cantonensis（AWA） were collected and analyzed using SDS-PAGE and Western blotting.Two ELISA systems were established using the two antigens（LESA-ELISA and AWA-ELISA） to detect the serum spectra from different sources.Results SDS-PAGE and Western blotting displayed fewer protein and antigen bands for LESA than for the adult antigen.Two distinct bands of LESA（with relative molecular masses of 40 000 and 26 000） showed reactivity with the sera from patients with A.cantonensis infection.The serum levels of IgG and IgM antibodies to LESA increased at the beginning of infection in mice,reaching the peak on day 5 after infection and decreased on day 10.Compared with AWA-ELISA,LESA-ELISA showed a lower seropositive ratio in suspected patients with A.cantonensis,with also a lower cross-positive ratio in patients with schistosomiasis and clonorchis sinensis.Conclusion LESA possesses fewer antigen reaction bands than AWA.Although with a slightly lower positive ratio than AWA,LESA has a higher specificity for detecting serum antibodies in suspected cases of A.cantonensis infection,and therefore shows a potential for the diagnosis of angiostrongyliasis especially in the early stage and in current infection.

关 键 词：广州管圆线虫 排泄分泌抗原 成虫抗原 免疫诊断 

分 类 号：R446.6[医药卫生—诊断学]