Group B streptococcus (GBS) is a gram-positive bacteria that asymptomatically colonizes the vaginal tract. However, during pregnancy maternal GBS colonization greatly predisposes the mother and baby to a wide range of adverse outcomes, including preterm birth (PTB), stillbirth, and neonatal infection. Although many mechanisms involved in GBS pathogenesis are partially elucidated, there is currently no approved GBS vaccine. The development of a safe and effective vaccine that can be administered during or prior to pregnancy remains a principal objective in the field, because current antibiotic-based therapeutic strategies do not eliminate all cases of invasive GBS infections. Herein, we review our understanding of GBS disease pathogenesis at the maternal-fetal interface with a focus on the bacterial virulence factors and host defenses that modulate the outcome of infection. We follow GBS along its path from an asymptomatic colonizer of the vagina to an invasive pathogen at the maternal-fetal interface, noting factors critical for vaginal colonization, ascending infection, and vertical transmission to the fetus. Finally, at each stage of infection we emphasize important host-pathogen interactions, which, if targeted therapeutically, may help to reduce the global burden of GBS.

中文翻译：

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妊娠期 B 组链球菌阴道定植和上升感染的细菌和宿主决定因素。

B 组链球菌 (GBS) 是一种革兰氏阳性细菌，无症状地定植于阴道。然而，在怀孕期间，母体 GBS 定植极大地使母亲和婴儿容易出现各种不良后果，包括早产 (PTB)、死产和新生儿感染。尽管涉及 GBS 发病机制的许多机制已部分阐明，但目前尚无批准的 GBS 疫苗。开发一种可以在怀孕期间或之前接种的安全有效的疫苗仍然是该领域的主要目标，因为目前基于抗生素的治疗策略并不能消除所有侵袭性 GBS 感染病例。在此处，我们回顾了我们对母胎界面 GBS 疾病发病机制的理解，重点关注调节感染结果的细菌毒力因子和宿主防御。我们跟踪 GBS 从无症状的阴道定植者到母胎界面的侵入性病原体的路径，注意到阴道定植、上行感染和垂直传播给胎儿的关键因素。最后，在感染的每个阶段，我们都强调重要的宿主-病原体相互作用，如果以治疗为目标，可能有助于减轻 GBS 的全球负担。并垂直传播给胎儿。最后，在感染的每个阶段，我们都强调重要的宿主-病原体相互作用，如果以治疗为目标，可能有助于减轻 GBS 的全球负担。并垂直传播给胎儿。最后，在感染的每个阶段，我们都强调重要的宿主-病原体相互作用，如果以治疗为目标，可能有助于减轻 GBS 的全球负担。