Stein K E, Zopf D A, Johnson B M, Miller C B, Paul W E
J Immunol. 1982 Mar;128(3):1350-4.
Two oligosaccharides derived from B512 dextran (Dex), isomaltohexaose (IM6), and isomaltotriose (IM3) have been coupled to keyhole limpet hemocyanin (KLH) and the conjugates studied as thymus-dependent (TD) immunogens analogous in their specificity to Dex. Both IM3-KLH and IM6-KLH stimulate an anti-Dex response in CBA mice. In C57BL mice, only IM6-KLH stimulated an anti-Dex response; IM3-KLH, although immunogenic, failed to elicit the production of anti-Dex antibodies. Similarly, CBA anti-Dex antibodies cross-reacted with both IM3 and IM6 coupled to bovine serum albumin (BSA), whereas C57BL anti-Dex antibodies cross-reacted with IM6-BSA and bound IM3-BSA only very poorly. This reciprocal lack of cross-reactivity between IM3 conjugates and Dex in C57BL mice was controlled by genes linked to the IgH locus, as shown in responses of allotype congenic CBA mice. This genetically regulated fine specificity pattern was overridden when IM6-KLH was used for immunization. C57BL antibodies that bound both Dex and IM3-BSA were produced in response to this antigen. Thus, isomaltohexosyl-protein conjugates provide Dex-like antigens that differ from Dex itself in terms of thymus dependency and the fine specificity of the precursors that are activated. They should provide important tools to study the activation requirements of antigen-specific B cells.
从B512葡聚糖（Dex）衍生而来的两种寡糖，异麦芽糖六糖（IM6）和异麦芽三糖（IM3），已与钥孔戚血蓝蛋白（KLH）偶联，并将这些偶联物作为与Dex特异性类似的胸腺依赖性（TD）免疫原进行研究。IM3-KLH和IM6-KLH均可刺激CBA小鼠产生抗Dex反应。在C57BL小鼠中，只有IM6-KLH刺激产生了抗Dex反应；IM3-KLH虽然具有免疫原性，但未能引发抗Dex抗体的产生。同样，CBA抗Dex抗体与偶联至牛血清白蛋白（BSA）的IM3和IM6均发生交叉反应，而C57BL抗Dex抗体与IM6-BSA发生交叉反应，与IM3-BSA的结合则非常差。如在同种异型同基因CBA小鼠的反应中所示，C57BL小鼠中IM3偶联物与Dex之间这种相互缺乏交叉反应性受与IgH基因座连锁的基因控制。当使用IM6-KLH进行免疫时，这种遗传调控的精细特异性模式被推翻。针对该抗原产生了与Dex和IM3-BSA均结合的C57BL抗体。因此，异麦芽糖己糖基蛋白偶联物提供了与Dex样的抗原，这些抗原在胸腺依赖性和被激活的前体的精细特异性方面与Dex本身不同。它们应提供重要的工具来研究抗原特异性B细胞的激活要求。
