Katzer F, McKellar S, Ben Miled L, D'Oliveira C, Shiels B
Department of Veterinary Parasitology, University of Glasgow, Scotland, UK.
Ann N Y Acad Sci. 1998 Jun 29;849:96-108. doi: 10.1111/j.1749-6632.1998.tb11039.x.
Tams1, the major merozoite/piroplasm surface antigen of Theileria annulata has the potential to be a component of a diagnostic ELISA test and be included in a recombinant subunit vaccine. However, the observation that this antigen displays diversity could constrain these applications. In this paper we have extensively characterized Tams1 diversity at the DNA level, using a PCR/sequencing strategy. Up to 44 alleles have been cloned and sequenced. The comparison of these alleles has identified regions of sequence conservation, variability and hyper-variability. Computer analysis of these alleles has indicated that positive selection may operate on certain regions of Tams1. Expression and Western blot analysis of selected alleles has indicated that sequence diversity is reflected in altered antigenicity and a continuum of relatedness and antibody cross recognition may exist. The possible function of the sequence conservation and polymorphism within Tams1 is discussed in relation to protein structure, host cell invasion and immune evasion.
Tams1是环形泰勒虫主要的裂殖子/梨形虫体表抗原，有潜力成为诊断性酶联免疫吸附测定（ELISA）检测的一个组成部分，并被纳入重组亚单位疫苗。然而，该抗原表现出多样性这一现象可能会限制这些应用。在本文中，我们使用聚合酶链反应/测序策略，在DNA水平上对Tams1的多样性进行了广泛表征。已克隆并测序了多达44个等位基因。对这些等位基因的比较确定了序列保守、可变和高度可变区域。对这些等位基因的计算机分析表明，正选择可能作用于Tams1的某些区域。对选定等位基因的表达和蛋白质印迹分析表明，序列多样性反映在抗原性改变上，并且可能存在一系列相关性和抗体交叉识别。本文结合蛋白质结构、宿主细胞入侵和免疫逃避，讨论了Tams1内序列保守和多态性的可能功能。
