Ghedin E, Zhang W W, Charest H, Sundar S, Kenney R T, Matlashewski G
Institute of Parasitology, Macdonald Campus, McGill University, Ste.-Anne de Bellevue, Quebec, Canada.
Clin Diagn Lab Immunol. 1997 Sep;4(5):530-5. doi: 10.1128/cdli.4.5.530-535.1997.
The antibody response against an amastigote-specific protein (A2) from Leishmania donovani was investigated. Sera from patients with trypanosomiasis and various forms of leishmaniasis were screened for anti-A2 antibodies. Sera from patients infected only with L. donovani or Leishmania mexicana specifically recognized the A2 recombinant protein. These results were consistent with karyotype analyses which revealed that the A2 gene is conserved in L. donovani and L. mexicana strains. The potential of this antigen in diagnosis was further explored by screening a series of sera obtained from patients in regions of the Sudan and India where L. donovani is endemic. The prevalence of anti-A2 antibodies was determined by Western blotting for all samples. Enzyme-linked immunosorbent assay (ELISA) and an immunoprecipitation assay were also performed on some of the samples. Anti-A2 antibodies were detected by ELISA in 82 and 60% of the samples from individuals with active visceral leishmaniasis (kala-azar) from the Sudan and India, respectively, while the immunoprecipitation assay detected the antibodies in 92% of the samples from India. These data suggest that the A2 protein may be a useful diagnostic antigen for visceral leishmaniasis.
对来自杜氏利什曼原虫的无鞭毛体特异性蛋白（A2）的抗体反应进行了研究。对锥虫病患者和各种形式利什曼病患者的血清进行了抗A2抗体筛查。仅感染杜氏利什曼原虫或墨西哥利什曼原虫的患者血清能特异性识别A2重组蛋白。这些结果与核型分析一致，核型分析显示A2基因在杜氏利什曼原虫和墨西哥利什曼原虫菌株中是保守的。通过筛查从苏丹和印度杜氏利什曼原虫流行地区患者获得的一系列血清，进一步探索了该抗原在诊断中的潜力。通过蛋白质印迹法测定所有样本中抗A2抗体的流行率。还对一些样本进行了酶联免疫吸附测定（ELISA）和免疫沉淀测定。通过ELISA在分别来自苏丹和印度的活动性内脏利什曼病（黑热病）患者的82%和60%的样本中检测到了抗A2抗体，而免疫沉淀测定在来自印度的92%的样本中检测到了抗体。这些数据表明，A2蛋白可能是内脏利什曼病的一种有用诊断抗原。
