Chiaramonte M G, Zwirner N W, Caropresi S L, Taranto N J, Malchiodi E L
Instituto de Estudios de las Inmunidad Humoral, Catedra de Inmunologia, Buenos Aires, Argentina.
Am J Trop Med Hyg. 1996 Mar;54(3):271-3. doi: 10.4269/ajtmh.1996.54.271.
The occurrence of leishmaniasis patients carrying a double infection with Trypanosoma cruzi has been suspected but not proved. In this study, we analyzed sera of leishmaniasis patients from a region endemic for both parasites by using immunoblotting with epimastigotes and a purified antigen specific for T. cruzi (Ag 163B6). Seven of 12 patients showed a pattern of bands characteristic of chagasic patients reacting with antigens with molecular weights of 131, 125, 116, 111, 51-45, and 43 kD, and positive reactivity with Ag 163B6. Xenodiagnosis for T. cruzi was carried out in all patients; this technique has a positivity rate of 50% in chronic chagasic patients. The presence of T. cruzi trypomastigotes was shown in the blood of three, thus confirming the existence of a double infection in humans. Since the two parasites possess cross-reacting antigens, it may be assumed that previous infection with one of the parasites may affect the course of subsequent infection with the other. Nevertheless, T. cruzi infection did not prevent the appearance of typical leishmaniasis lesions. Therefore, antigenic cross-reactivity is unable to induce a sterilizing immune response against Leishmania.
曾怀疑有携带克氏锥虫双重感染的利什曼病患者，但尚未得到证实。在本研究中，我们通过用前鞭毛体进行免疫印迹分析以及使用一种针对克氏锥虫的纯化抗原（Ag 163B6），对来自两种寄生虫均为地方流行区的利什曼病患者血清进行了分析。12名患者中有7名呈现出恰加斯病患者特有的条带模式，与分子量为131、125、116、111、51 - 45和43 kD的抗原发生反应，并与Ag 163B6呈阳性反应。对所有患者进行了克氏锥虫的异种诊断；该技术在慢性恰加斯病患者中的阳性率为50%。在三名患者的血液中发现了克氏锥虫无鞭毛体，从而证实了人类存在双重感染。由于这两种寄生虫具有交叉反应抗原，因此可以假设先前感染其中一种寄生虫可能会影响随后感染另一种寄生虫的病程。然而，克氏锥虫感染并未阻止典型利什曼病病变的出现。因此，抗原交叉反应无法诱导针对利什曼原虫的杀菌免疫反应。
