Skip to main content

Novel influenza A antibodies reduce severity of secondary pneumococcal pneumonia after influenza infection in mice

Introduction

Secondary bacterial pneumonia after influenza infection can cause severe disease with a high mortality. Recently, a new group 2 influenza A antibody (AT10_002) has been developed, which binds to multiple H3 and H7 subtypes. In a mouse model of primary influenza infection, treatment with AT10_002 as a fusion antibody protects against lethal infection, and reduces loss of bodyweight [1]. We hypothesized that treatment with AT10_002 reduces weight loss, lung injury and bacterial outgrowth, in a mouse model of viral infection followed by secondary pneumococcal infection.

Methods

Male C57Bl/6 mice were intranasally inoculated with 400 TCID50 Influenza A (H3N2). Two days after infection, mice were injected with either AT10_002 i.v. (n = 8) or a control antibody (n = 7). After 7 days, both groups were intranasally inoculated with 5 × 103 S. pneumoniae type 3 and were sacrificed 18 hours later. Outcome measures were weight loss, wet lung weight, cell count in bronchoalveolar lavage fluid (BALF), and colony-forming units (CFUs) in lung homogenate. Data are represented as medians, and treatment groups are compared using nonparametric tests.

Results

Mice receiving AT10_002 showed significantly lower weight loss at the time of sacrifice compared with the control group (+1% vs. -12% change in weight; P = 0.0003). Also wet lung weight was lower (68 vs. 96 mg; P = 0.0003), cell counts in BALF were lower (4.9 × 105 vs. 7.0 × 105 cells/ml; P = 0.0037) and CFUs in lung homogenate were lower (33 vs. 25 × 104 CFUs/mg; P = 0.0003) compared with controls.

Conclusion

Early treatment with influenza antibody AT10_002 significantly reduces weight loss, lung injury and bacterial outgrowth, in a mouse model of influenza infection followed by secondary pneumococcal pneumonia.

References

  1. 1.

    Wagner K, et al: Proc Natl Acad Sci U S A. 2014, 111: 16820-5. 10.1073/pnas.1408605111.

    PubMed Central  CAS  Article  PubMed  Google Scholar 

Download references

Author information

Affiliations

Authors

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Van der Sluijs, K., Van Someren Greve, F., Jong, M.D. et al. Novel influenza A antibodies reduce severity of secondary pneumococcal pneumonia after influenza infection in mice. Crit Care 19, P103 (2015). https://doi.org/10.1186/cc14183

Download citation

Keywords

  • Influenza
  • Lung Injury
  • Bacterial Outgrowth
  • Bronchoalveolar Lavage
  • Lavage Fluid