Studies have indicated that purified soluble polysaccharide antigens can elicit T cell-independent Ig responses in vivo, although these responses can be modulated by T cells in a noncognate manner. Relatively little is known, however, concerning the parameters that regulate polysaccharide-specific, as well as protein-specific, Ig isotype responses to an intact extracellular bacterium. Using the murine in vivo humoral response to intact Streptococcus pneumoniae as a model it can be shown that CD4+ T-cell receptor alphabeta+ T cells deliver help for both polysaccharide- and protein-specific Ig responses. However, these responses differ fundamentally in their mechanism of action.

中文翻译：

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不同类型的T细胞有助于诱导对肺炎链球菌的体液免疫反应。

研究表明，纯化的可溶性多糖抗原可以在体内引起非T细胞依赖性Ig反应，尽管这些反应可以由T细胞以非同源方式调节。然而，关于调节对完整的细胞外细菌的多糖特异性以及蛋白质特异性Ig同种型应答的参数知之甚少。使用鼠对完整肺炎链球菌的体内体液反应作为模型，可以证明CD4 + T细胞受体字母+ T细胞可为多糖和蛋白质特异性Ig反应提供帮助。但是，这些反应的作用机理根本不同。