Genetic susceprtibity to acute or chronic schistosomiasis japonica

1.利用患者血清对血吸虫卵cDNA文库中主要抗原进行分子克隆。我们已经发现中国患者中存在相对耐药和易感的hla II类单倍型。这一年，我们寻找能够刺激HLA单倍型阳性个体的T细胞的主要抗原，因为T细胞反应被认为是发病机制中最重要的。利用lambda gt11i噬菌体系统从中国一株新分离的卵细胞中提取mRNA构建cDNA文库，并用IgG检测系统筛选与混合血清反应的主要抗原。最终分离得到200个阳性克隆，其中146个克隆直接测序。结果出乎意料，因为所有克隆都是一个名为miracidial antigen的基因的几个部分。克隆的基因通过GST融合蛋白系统成功表达。再感染研究在三个不同的村庄。我们发现了两件事。一种是人群中没有年龄依赖性的抵抗力另一种是存在两类人，抵抗性的和对再次感染易感的。我们发现耐药者HLA-DRB1型共享其第67个氨基酸苯丙氨酸，而不是具有第67个亮氨酸或异亮氨酸。由于67F或I/L对于形成一个结合口袋很重要，因此激发一些保护性免疫反应将是至关重要的。重组副肌球蛋白在中国家猪的免疫试验。在中国流行区，重要的是控制水库宿主，如猪和水牛的感染。我们使用家猪和重组副肌球蛋白进行了疫苗试验研究。对80多头猪的广泛研究表明，猪对挑战感染很敏感，并且在接种了副肌球蛋白和减毒尾蚴后，对感染产生了免疫力。少

1.Molecular cloning of the major antigens from a cDNA library of schistosomal egg by using patients pooled sera.We have already found there are relatively resistant and susceptible HLA-class II haplotypes present in the Chinese patients against post-schistosomal liver fibrosis. This 'ear we seeked for the major antigens that would stimulate those HLA haplotypes positive individuals' T cells, because T cell response is assumed to be the most important in the pathogenesis. A cDNA library was prepared from a mRNA extracted from the freshly isolated eggs of a Chinese strain using lambda gt11 I phage system and was screened for the major antigens reactive with pooled sera by IgG detection system. Finally 200 positive clones were isolated and 146 clones out of those were directly sequenced. The result was unexpected because all the clones were several parts of one gene named miracidial antigen. The cloned gene was successfully expressed by GST fusion protein system.2. Re-infection study in t … More hree different villages.We have found two things. One is that there was no age dependent resistance in the population and the other is that there were two categories of people present, resistant and susceptible against re-infection. We have found that the HLA-DRB1 types that resistant persons had shared its 67th amino acid, phenylalanine, instead of having 67 leucine or isoleucine. Because the 67F or I/L is important to make a binding pocket, it would be critical to provoke some protective immune response.3. Vaccination trial of domestic pigs with recombinant paramyosin in China.In the endemic area in China, it is important to control the infection of the reservoir hosts, such as pigs and water buffaloes. We have performed a vaccine trial study using domestic pigs and recombinant paramyosin. The extensive study using more than 80 pigs revealed that the pigs were susceptible to challenge infection and were provoked immunity against infection after the vaccination with paramyosin as well as with attenuated cercariae (Vaccine in Press). Less