eLife (Sep 2021)

Vaccination induces rapid protection against bacterial pneumonia via training alveolar macrophage in mice

  • Hao Gu,
  • Xi Zeng,
  • Liusheng Peng,
  • Chuanying Xiang,
  • Yangyang Zhou,
  • Xiaomin Zhang,
  • Jixin Zhang,
  • Ning Wang,
  • Gang Guo,
  • Yan Li,
  • Kaiyun Liu,
  • Jiang Gu,
  • Hao Zeng,
  • Yuan Zhuang,
  • Haibo Li,
  • Jinyong Zhang,
  • Weijun Zhang,
  • Quanming Zou,
  • Yun Shi

DOI
https://doi.org/10.7554/eLife.69951
Journal volume & issue
Vol. 10

Abstract

Read online

Vaccination strategies for rapid protection against multidrug-resistant bacterial infection are very important, especially for hospitalized patients who have high risk of exposure to these bacteria. However, few such vaccination strategies exist due to a shortage of knowledge supporting their rapid effect. Here, we demonstrated that a single intranasal immunization of inactivated whole cell of Acinetobacter baumannii elicits rapid protection against broad A. baumannii-infected pneumonia via training of innate immune response in Rag1-/- mice. Immunization-trained alveolar macrophages (AMs) showed enhanced TNF-α production upon restimulation. Adoptive transfer of immunization-trained AMs into naive mice mediated rapid protection against infection. Elevated TLR4 expression on vaccination-trained AMs contributed to rapid protection. Moreover, immunization-induced rapid protection was also seen in Pseudomonas aeruginosa and Klebsiella pneumoniae pneumonia models, but not in Staphylococcus aureus and Streptococcus pneumoniae model. Our data reveal that a single intranasal immunization induces rapid and efficient protection against certain Gram-negative bacterial pneumonia via training AMs response, which highlights the importance and the possibility of harnessing trained immunity of AMs to design rapid-effecting vaccine.

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