James Michael J, Yabsley Michael J, Pung Oscar J, Grijalva Mario J
Tropical Diseases Institute, Ohio University College of Osteopathic Medicine, Athens 45701, USA.
J Parasitol. 2002 Oct;88(5):989-93. doi: 10.1645/0022-3395(2002)088[0989:AOTCSD]2.0.CO;2.
This investigation applied polymerase chain reaction (PCR) using 3 sets of Trypanosoma cruzi-specific primers to amplify DNA from 31 archived formalin-fixed and fresh-frozen raccoon hearts. PCR successfully amplified T. cruzi-specific sequences, with at least 1 primer set, from multiple sites within the myocardium of formalin-fixed and fresh-frozen raccoon hearts that had previously tested positive using enzyme-linked immunosorbent assay and indirect immunofluorescent antibody titer in the absence of positive hemoculture results. Trypanosoma cruzi DNA was most frequently amplified from the interventricular septum, right ventricle, and left atrium. In addition, T. cruzi DNA was amplified with all 3 primers in at least I raccoon that was hemoculture positive and 2 animals that were borderline negative for the T. cruzi antibody and hemoculture negative. The amplification of T. cruzi-specific DNA sequences in the presence of an elevated antibody titer and negative culture results suggests good sensitivity of this method for detecting the presence of the parasite in archival tissues.
本研究应用聚合酶链反应（PCR），使用3组克氏锥虫特异性引物，从31份存档的福尔马林固定和新鲜冷冻的浣熊心脏中扩增DNA。PCR成功地从福尔马林固定和新鲜冷冻的浣熊心脏心肌内的多个位点，用至少1组引物扩增出克氏锥虫特异性序列，这些心脏在之前酶联免疫吸附测定和间接免疫荧光抗体滴度检测中呈阳性，但血培养结果为阴性。克氏锥虫DNA最常从室间隔、右心室和左心房中扩增出来。此外，在至少1只血培养阳性以及2只克氏锥虫抗体检测呈临界阴性且血培养阴性的动物中，使用所有3组引物均扩增出了克氏锥虫DNA。在抗体滴度升高而培养结果为阴性的情况下扩增出克氏锥虫特异性DNA序列，表明该方法在检测存档组织中寄生虫存在方面具有良好的敏感性。
