Partidos C, Stanley C, Steward M
Department of Clinical Sciences, London School of Hygiene and Tropical Medicine, GB.
Eur J Immunol. 1992 Oct;22(10):2675-80. doi: 10.1002/eji.1830221030.
CBA and TO mice were immunized with chimeric peptide immunogens consisting of B cell (residues 404-414) and T cell (residues 288-302) epitopes from the F protein of measles virus. The chimeras were co-linearly synthesized to contain one or two copies of the T cell epitope linked to one or two copies of the B cell epitope via a glycine.glycine spacer. Two orientations were synthesized such that the T cell epitope(s) were located at either the amino or carboxyl terminus of the B cell epitope(s). The levels of antibody induced following immunization with the chimeras were assessed by enzyme-linked immunosorbent assay using microtiter plates coated with either the homologous chimera or the B cell epitope sequence. The affinities of the anti-chimera antibodies for the B cell epitope were assessed by a fluid-phase double-isotope radioimmunoassay. All the chimeras induced good antibody responses in both strains of mice with specificity for the B cell epitope. Chimeras containing two copies of the T cell epitope induced antibodies with higher affinity for the B cell epitope than did chimeras containing one copy of the T cell epitope or two copies of the B cell epitope. Furthermore, the amino terminal location of the T cell epitope in relation to the B cell epitope in the chimera induced higher affinity anti-B cell antibody than did the reverse orientation. These results suggest that orientation of epitopes and amino acid composition of chimeric peptides affect antigen processing and presentation to T cells which govern both the specificity and affinity of antibody produced. Thus, for the production of synthetic peptide immunogens with vaccine potential, attention needs to be given to the number and orientation of the component epitopes required to produce highest affinity antibody.
用由麻疹病毒F蛋白的B细胞（404 - 414位氨基酸）和T细胞（288 - 302位氨基酸）表位组成的嵌合肽免疫原免疫CBA和TO小鼠。这些嵌合体通过甘氨酸 - 甘氨酸间隔区共线性合成，包含与一或两个B细胞表位拷贝相连的一或两个T细胞表位拷贝。合成了两种方向，使得T细胞表位位于B细胞表位的氨基端或羧基端。用包被有同源嵌合体或B细胞表位序列的微量滴定板通过酶联免疫吸附测定法评估用嵌合体免疫后诱导的抗体水平。通过液相双同位素放射免疫测定法评估抗嵌合抗体对B细胞表位的亲和力。所有嵌合体在两种小鼠品系中均诱导出对B细胞表位具有特异性的良好抗体反应。与含有一个T细胞表位拷贝或两个B细胞表位拷贝的嵌合体相比，含有两个T细胞表位拷贝的嵌合体诱导出对B细胞表位具有更高亲和力的抗体。此外，与相反方向相比，嵌合体中T细胞表位相对于B细胞表位的氨基端位置诱导出更高亲和力的抗B细胞抗体。这些结果表明，表位的方向和嵌合肽的氨基酸组成影响抗原加工和向T细胞的呈递，而T细胞决定所产生抗体的特异性和亲和力。因此，为了生产具有疫苗潜力的合成肽免疫原，需要关注产生最高亲和力抗体所需的组成表位的数量和方向。
