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

对克氏环锯的易感性与产生IL-4的Th 2细胞的扩增有关，而抵抗性与产生干扰素γ（IFN-γ）的Th 1细胞的扩增有关。在Th 1或Th 2细胞发育起始时起作用的机制在感染后形成共同的CD 4 + T细胞前体是不清楚的。为了解Th 1细胞分泌IFN-γ的功能，将IFN-γ与外鞭毛体共同培养。IFN-γ能促进外鞭毛体的增殖。在中美洲，Chagas病的临床表现与南美洲不同，中美洲以心脏疾病为特征，而南美洲则以消化系统和心脏疾病为常见。这种差异的原因之一可能是T.克鲁兹迄今为止，关于T. cruzi来自中美洲和那些来自南方。对分离的T. cruzi从危地马拉、中美洲和南美洲国家获得的寄生虫，并比较了这两个地区的寄生虫的遗传结构。在获得的各种模式，几个酶基因彼此密切相关的发现在危地马拉人口，虽然有些被发现在分离株从南美洲，太。两个密切相关的酶组独特的南美洲，有很大的不同，从危地马拉的酶组。本研究结果提示，致病性差异可能与遗传变异有关。cruzi in中南美洲

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