Studies of protective immunity in Chages' disease-the role of immune response related genes-

对弯曲病的易感性与产生IL-4的Th2细胞的扩张有关，而耐药性与产生干扰素γ(干扰素-γ)的Th1细胞的扩张有关。在感染后启动Th1或Th2细胞发育形成共同的CD4‘T细胞前体的机制尚不清楚。为了解Th1细胞分泌干扰素-γ的功能，用干扰素-γ对上胚体进行培养。干扰素-γ可促进上鞭毛体的增殖。干扰素-γ对锥虫LLC-M细胞的感染增加。查加斯病在中美洲和南美洲的临床类型不同，心脏疾病在中美洲是特征，而消化和心脏疾病在南美洲是常见的。造成这种差异的可能原因之一似乎是克氏锥虫的遗传差异。到目前为止，关于来自中美洲的克氏锥虫和来自南方的克氏锥虫的遗传差异的报道很少。我们对来自危地马拉、中美洲和南美国家的克鲁兹毛滴虫分离株进行了同工酶分析，并比较了这两个地区的这种寄生虫的遗传结构。在获得的各种模式中，在危地马拉人群中发现了几个遗传上彼此密切相关的酵母菌，尽管也在南美洲的分离株中发现了一些。南美洲特有的两个密切相关的酵母菌，与危地马拉的酵母菌有很大的不同。本研究结果提示，克氏锥虫在中南美洲的致病性差异可能与其遗传变异有关。

The susceptibility to trepanations cruzi is associated with the expansion IL-4 producing Th2 cells, whereas the resistance is correlates with the expansion of Th1 cells producing interferon γ(IFN-γ). The mechanisms operating at the initiation of Th1 or Th2 cell development form common CD4'T cell precursors after infection are not cleat. To understand the fuction of IFN-γ released from Th1, epimastigote were cultured with IFN-γ. The prolifreation of epimastigote increased by IFN-γ. Infection to LLC-M cells of tryposatigotes increased by IFN-γ.The clinical pattern of Chagas' disease in Central America is different from that in South America; cardiac disorder is characteristic in Central America, while doth the digestive and cardiac disorders are common is South America. One of the possible causes of this differences seems to be genetic difference in T. cruzi. So far there have been few reports on the genetic differences between T. cruzi from Central America and those from South. We carried out isozyme analysis of isolates of T. cruzi obtained from Guatemala, Central America and those from South American countries, and compared the genetic structures of this parasite from both areas. Among various patterns obtained, several zymodemes genetically closely related to each other were found in Guatemalan populations, although some were found in isolates from South America, too. Two closely related zymodemes unique to South America, differed greatly from Guatemalan zymodemes. The results of this study suggest that the genetic variations might be related to the differences in pathogenicity of T. cruzi in Centraland South Americas