Avila H A, Pereira J B, Thiemann O, De Paiva E, DeGrave W, Morel C M, Simpson L
Department of Biology, University of California, Los Angeles 90024.
J Clin Microbiol. 1993 Sep;31(9):2421-6. doi: 10.1128/jcm.31.9.2421-2426.1993.
A panel of 114 blood samples from chronic chagasic patients and nonchagasic patients was screened for Trypanosoma cruzi by xenodiagnostic, serologic, and polymerase chain reaction (PCR) amplification tests. Blood samples were preserved in a guanidine-EDTA buffer, and total blood DNA was isolated after chemical nuclease cleavage with 1,10-phenanthroline-copper ion and used as a template for PCR amplification of the conserved and variable regions of T. cruzi minicircle molecules. The PCR products were screened by Southern blot hybridization with a digoxigenin-labeled oligonucleotide probe specific for the conserved region of the minicircle. The method showed a sensitivity of 100% compared with the serologic test. In addition, all of the serology-positive, xenodiagnosis-negative samples were positive by PCR. This demonstrates that PCR amplification of T. cruzi kinetoplast minicircle DNA could replace xenodiagnosis for evaluation of parasitemia in chronic chagasic patients and could serve as a complement for serologic testing in the screening of blood bank donors.
通过异种诊断、血清学和聚合酶链反应（PCR）扩增试验，对一组来自慢性恰加斯病患者和非恰加斯病患者的114份血样进行克氏锥虫筛查。血样保存在胍-EDTA缓冲液中，经1,10-菲咯啉-铜离子化学核酸酶切割后分离出全血DNA，并用作PCR扩增克氏锥虫微小环分子保守区和可变区的模板。用针对微小环保守区的地高辛标记寡核苷酸探针通过Southern印迹杂交筛选PCR产物。与血清学检测相比，该方法显示出100%的灵敏度。此外，所有血清学阳性、异种诊断阴性样本经PCR检测均为阳性。这表明，克氏锥虫动基体微小环DNA的PCR扩增可替代异种诊断用于评估慢性恰加斯病患者的寄生虫血症，并且可作为血库供血者筛查中血清学检测的补充。
