Department of Otolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama-city, Wakayama, Japan.
PLoS One. 2011;6(10):e27102. doi: 10.1371/journal.pone.0027102. Epub 2011 Oct 31.
Pathogen-specific antibody plays an important role in protection against pneumococcal carriage and infections. However, neonates and infants exhibit impaired innate and adaptive immune responses, which result in their high susceptibility to pneumococci. To protect neonates and infants against pneumococcal infection it is important to elicit specific protective immune responses at very young ages. In this study, we investigated the protective immunity against pneumococcal carriage, pneumonia, and sepsis induced by maternal immunization with pneumococcal surface protein A (PspA). Mother mice were intranasally immunized with recombinant PspA (rPspA) and cholera toxin B subunit (CTB) prior to being mated. Anti-PspA specific IgG, predominantly IgG1, was present at a high level in the serum and milk of immunized mothers and in the sera of their pups. The pneumococcal densities in washed nasal tissues and in lung homogenate were significantly reduced in pups delivered from and/or breast-fed by PspA-immunized mothers. Survival after fatal systemic infections with various types of pneumococci was significantly extended in the pups, which had received anti-PspA antibody via the placenta or through their milk. The current findings strongly suggest that maternal immunization with PspA is an attractive strategy against pneumococcal infections during early childhood.
病原体特异性抗体在预防肺炎球菌定植和感染方面发挥着重要作用。然而，新生儿和婴儿的固有和适应性免疫反应受损，导致他们对肺炎球菌高度易感。为了保护新生儿和婴儿免受肺炎球菌感染，在非常年幼的时候引发特定的保护性免疫反应非常重要。在这项研究中，我们研究了通过肺炎球菌表面蛋白 A（PspA）的母体免疫接种引起的对肺炎球菌定植、肺炎和败血症的保护免疫。在交配前，母鼠通过鼻腔内免疫接种重组 PspA（rPspA）和霍乱毒素 B 亚单位（CTB）。免疫母鼠的血清和乳汁中存在高水平的抗 PspA 特异性 IgG，主要是 IgG1，而其幼崽的血清中也存在抗 PspA 特异性 IgG，主要是 IgG1。经 rPspA 免疫的母鼠所产幼崽的鼻腔组织和肺匀浆中的肺炎球菌密度明显降低。通过胎盘或通过乳汁获得抗 PspA 抗体的幼崽在致命性全身感染各种类型的肺炎球菌后，存活时间明显延长。这些发现强烈表明，用 PspA 进行母体免疫接种是预防儿童早期肺炎球菌感染的一种有吸引力的策略。
