Knight P, Musoke A J, Gachanja J N, Nene V, Katzer F, Boulter N, Hall R, Brown C G, Williamson S, Kirvar E, Bell-Sakyi L, Hussain K, Tait A
Department of Veterinary Parasitology, University of Glasgow, UK.
Exp Parasitol. 1996 Apr;82(3):229-41. doi: 10.1006/expr.1996.0030.
The sporozoite surface antigens SPAG-1 of Theileria annulata and p67 of Theileria parva are postulated to contain determinants necessary for host cell invasion and/or recognition and are both being considered as candidates for inclusion in subunit vaccines. Preliminary data suggest that these are related molecules. In this paper we describe the investigation of the relationship between these sporozoite antigens further by analysis of the immunological cross-reactivity using Mabs and sera raised against each antigen. The cross-reactions were examined by carrying out Western blots, IFA tests, and in vitro sporozoite neutralization assays. In addition, sequence comparison data which clearly establish that these surface antigens are encoded by related genes are presented. The regions of SPAG-1 identified as containing cross-reactive epitopes recognized by p67 antiserum correlated to regions of high predicted homology between p67 and SPAG-1, which are located at their respective N- and C-termini. Furthermore, p67 and SPAG-1 were found to contain cross-reactive determinants responsible for neutralization of sporozoite infectivity in vitro, and at least some of these were located in the C-termini of both molecules. The relevance of these findings to the possible roles for these molecules in host cell invasion is discussed.
环形泰勒虫的子孢子表面抗原SPAG-1和小泰勒虫的p67被推测含有宿主细胞入侵和/或识别所必需的决定簇，二者均被视为亚单位疫苗的候选成分。初步数据表明它们是相关分子。在本文中，我们通过分析使用针对每种抗原产生的单克隆抗体和血清的免疫交叉反应性，进一步描述了对这些子孢子抗原之间关系的研究。通过进行蛋白质免疫印迹、间接免疫荧光试验和体外子孢子中和试验来检测交叉反应。此外，还展示了明确证实这些表面抗原由相关基因编码的序列比较数据。被p67抗血清识别为含有交叉反应性表位的SPAG-1区域，与p67和SPAG-1之间预测同源性高的区域相关，这些区域位于它们各自的N端和C端。此外，发现p67和SPAG-1含有负责体外中和子孢子感染性的交叉反应决定簇，其中至少一些位于这两种分子的C端。讨论了这些发现与这些分子在宿主细胞入侵中可能作用的相关性。
