Our bodies are constantly exposed to a wide variety of pathogenic micro-organisms through mucosal sites. Therefore, effective vaccines that can protect at the mucosa are vital; however, only a few clinically established mucosal vaccines are available. Although conventional injectable vaccines can induce antigen-specific serum immunoglobulin G (IgG) and prevent severe infection, it is difficult to efficiently inhibit the invasion of pathogens at mucosal surfaces because of the inadequate ability to induce antigen-specific IgA. Recently, we have developed a parenteral vaccine with emulsified curdlan and CpG oligodeoxynucleotides and reported its application. Unlike other conventional injectable vaccines, this immunization contributes to the induction of antigen-specific mucosal and systemic immune responses. Even if antigen-specific IgA at the mucosa disappears, this immunization can induce high-titer IgA after boosting with a small amount of antigen on the target mucosal surface. Indeed, vaccination with Streptococcus pneumoniae antigen effectively prevented lung infection induced by this bacterium. In addition, vaccination with Clostridium ramosum, which is a representative pathobiont associated with obesity and diabetes in humans, reduced obesity in mice colonized with this microorganism. This immunization approach might be an effective treatment for intestinal bacteria-mediated diseases that have been difficult to regulate so far, as well as common infectious diseases.

中文翻译：

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初级-加强型下一代粘膜疫苗的开发。

我们的身体通过粘膜部位不断暴露于各种病原微生物。因此，能够保护粘膜的有效疫苗至关重要；然而，只有少数临床建立的粘膜疫苗可用。常规注射疫苗虽然可以诱导抗原特异性血清免疫球蛋白G（IgG）并预防严重感染，但由于诱导抗原特异性IgA的能力不足，难以有效抑制病原体在粘膜表面的侵袭。最近，我们开发了一种含有乳化凝胶多糖和CpG寡脱氧核苷酸的肠外疫苗并报道了其应用。与其他常规注射疫苗不同，这种免疫有助于诱导抗原特异性粘膜和全身免疫反应。即使黏膜上的抗原特异性 IgA 消失，这种免疫也可以在目标黏膜表面用少量抗原加强免疫后诱导产生高滴度 IgA。确实，接种肺炎链球菌抗原有效地防止了这种细菌引起的肺部感染。此外，接种梭状芽孢杆菌（一种与人类肥胖和糖尿病相关的代表性病原体）可减少被这种微生物定植的小鼠的肥胖。这种免疫方法可能是治疗迄今为止难以调节的肠道细菌介导的疾病以及常见传染病的有效方法。