Biología Celular, Histología y Embriología, Facultad Cs. Médicas Universidad Nacional de Córdoba, Enrique Barros y Enfermera Gordillo s/n, Ciudad Universitaria, Córdoba, Argentina.
Trans R Soc Trop Med Hyg. 2009 Oct;103(10):1011-8. doi: 10.1016/j.trstmh.2009.03.004. Epub 2009 Apr 1.
Chagas disease is caused by Trypanosoma cruzi, which can be transmitted to the fetus via the transplacental route. Factors that may be involved in transplacental transmission include parasite strain and placental immunological competence. The aim of this work was to compare the biological differences between two subpopulations of T. cruzi with respect to their interaction with the human placenta in vitro. We found that the Tulahuen strain (sublineage TcIIe) and another strain isolated from a congenitally infected newborn child had similar rates of productive infection in human chorionic villi in vitro, with similar deleterious nitric oxide levels between the two strains. We also found that the congenital T. cruzi stock had a greater ability than the Tulahuen strain to survive in the placental deleterious media, with the difference acquiring more importance considering the low reproductive rate of both subpopulations of T. cruzi within placental cells. As the presence of T. cruzi is a necessary condition to produce congenital transmission, we propose that the different survival rates of strains of T. cruzi in an adverse placental environment offer an opportunity for the parasite to infect the placenta in order to produce a sustainable infection during pregnancy, with the subsequent possibility of infecting the fetus.
恰加斯病由克氏锥虫引起，可通过胎盘途径传播给胎儿。可能涉及胎盘传播的因素包括寄生虫株和胎盘免疫能力。本工作的目的是比较两种克氏锥虫亚群与体外人胎盘相互作用的生物学差异。我们发现，Tulahuen 株（TcIIe 亚系）和另一种从先天性感染新生儿中分离出的株，在体外人绒毛膜绒毛中的感染率相似，两株之间的有害一氧化氮水平相似。我们还发现，先天性克氏锥虫株比 Tulahuen 株更能在胎盘有害介质中存活，考虑到两种克氏锥虫亚群在胎盘细胞内的低繁殖率，这种差异变得更为重要。由于克氏锥虫的存在是产生先天性传播的必要条件，我们提出，克氏锥虫株在不利的胎盘环境中的不同存活率为寄生虫感染胎盘提供了机会，以便在怀孕期间产生持续感染，随后可能感染胎儿。
