Martins H R, Toledo M J O, Veloso V M, Carneiro C M, Machado-Coelho G L L, Tafuri W L, Bahia M T, Valadares H M, Macedo A M, Lana M
Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Instituto de Ciências Exatas e Biológicas (ICEB), UFOP, MG, Brazil.
Exp Parasitol. 2006 Apr;112(4):237-46. doi: 10.1016/j.exppara.2005.11.006. Epub 2006 Jan 9.
Herein, we have analyzed major biological properties following dual-clone Trypanosoma cruzi infections in BALB/c mice. Eight T. cruzi clonal stocks, two of each principal genotype, including genotype 19 and 20 (T. cruzi I), hybrid genotype 39 (T. cruzi) and 32 (T. cruzi II) were combined into 24 different dual-clone infections. Special attention was given to characterize biological parameters assayed including: prepatent period, patent period, maximum of parasitemia, day of maximum parasitemia, area under the parasitemia curve, infectivity, mortality, and hemoculture positivity. Our findings clearly demonstrated that features resultant of dual-clone infections of T. cruzi clonal stocks did not display either the characteristics of the corresponding monoclonal infections or the theoretical mixture based on the respective monoclonal infections. Significant changes in the expected values were observed in 4.2-79.2% of the mixtures considering the eight biological parameters studied. A lower frequency of significant differences was found for mixtures composed by phylogenetically distant clonal stocks. Altogether, our data support our hypothesis that mixed T. cruzi infections have a great impact on the biological properties of the parasite in the host and re-emphasizes the importance of considering the possible occurrence of natural mixed infections in humans and their consequences on the biological aspects of ongoing Chagas' disease.
在此，我们分析了BALB/c小鼠双重克隆克氏锥虫感染后的主要生物学特性。八种克氏锥虫克隆株，每种主要基因型各两种，包括基因型19和20（克氏锥虫I）、杂交基因型39（克氏锥虫）和32（克氏锥虫II），被组合成24种不同的双重克隆感染。我们特别关注了所测定的生物学参数的特征，包括：潜伏期、发病期、最高寄生虫血症、最高寄生虫血症出现的天数、寄生虫血症曲线下面积、感染性、死亡率和血培养阳性率。我们的研究结果清楚地表明，克氏锥虫克隆株双重克隆感染产生的特征既未表现出相应单克隆感染的特征，也未表现出基于各自单克隆感染的理论混合特征。考虑到所研究的八个生物学参数，在4.2%至79.2%的混合物中观察到预期值的显著变化。在由系统发育距离较远的克隆株组成的混合物中，发现显著差异的频率较低。总之，我们的数据支持了我们的假设，即克氏锥虫混合感染对宿主体内寄生虫的生物学特性有很大影响，并再次强调了考虑人类自然混合感染的可能发生及其对正在进行的恰加斯病生物学方面的影响的重要性。
