Abstract

Gram-positive bacterial pathogens that secrete cytotoxic pore-forming toxins, such as Staphylococcus aureus and Streptococcus pneumoniae, cause a substantial burden of disease. Inspired by the principles that govern natural toxin-host interactions, we have engineered artificial liposomes that are tailored to effectively compete with host cells for toxin binding. Liposome-bound toxins are unable to lyse mammalian cells in vitro. We use these artificial liposomes as decoy targets to sequester bacterial toxins that are produced during active infection in vivo. Administration of artificial liposomes within 10 h after infection rescues mice from septicemia caused by S. aureus and S. pneumoniae, whereas untreated mice die within 24–33 h. Furthermore, liposomes protect mice against invasive pneumococcal pneumonia. Composed exclusively of naturally occurring lipids, tailored liposomes are not bactericidal and could be used therapeutically either alone or in conjunction with antibiotics to combat bacterial infections and to minimize toxin-induced tissue damage that occurs during bacterial clearance.

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Acknowledgements

We gratefully acknowledge the financial support of the University of Bern, Commission for Technology and Innovation (CTI) (16001.1 PFLS-LS to A.D. and E.B.B.), Deutsche Forschungsgemeinschaft (DFG GU 335/16-2 to E.G. and SFB 1112 to B.K.), Federal Ministry of Education and Research (BMBF) (FKZ: 01EO1002 to A.S.) and the Institute of Infection & Global Health, University of Liverpool to A.K.

Author information

Author notes

    • Kathrin Mühlemann

    Deceased.

    • Brian D Henry
    • , Daniel R Neill
    •  & Katrin Anne Becker

    These authors contributed equally to this work.

    • Erich Gulbins
    • , Aras Kadioglu
    • , Annette Draeger
    •  & Eduard B Babiychuk

    These authors jointly directed this work.

Affiliations

  1. Institute of Molecular Biology, University of Duisburg-Essen, Essen, Germany.

    • Brian D Henry
    • , Katrin Anne Becker
    • , Regan Ziobro
    •  & Erich Gulbins
  2. Department of Surgery, University of Cincinnati, Cincinnati, Ohio, USA.

    • Brian D Henry
    • , Regan Ziobro
    • , Michael J Edwards
    •  & Erich Gulbins
  3. Department of Clinical Infection Microbiology & Immunology, Institute of Infection & Global Health, University of Liverpool, Liverpool, UK.

    • Daniel R Neill
    • , Suzanna Gore
    • , Laura Bricio-Moreno
    •  & Aras Kadioglu
  4. Institute for Infectious Diseases, University of Bern, Bern, Switzerland.

    • Kathrin Mühlemann
  5. Institute of Medical Microbiology, University of Duisburg-Essen, Essen, Germany.

    • Jörg Steinmann
  6. Department of Toxicology, Institute of Nutritional Science, University of Potsdam, Potsdam, Germany.

    • Burkhard Kleuser
    •  & Lukasz Japtok
  7. Institute of Anatomy, University of Bern, Bern, Switzerland.

    • Miriam Luginbühl
    • , Heidi Wolfmeier
    • , Annette Draeger
    •  & Eduard B Babiychuk
  8. Clinical Epidemiology, Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), Jena University Hospital, Jena, Germany.

    • André Scherag

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Contributions

B.D.H., D.R.N. and K.A.B. contributed equally to this study. B.D.H., K.A.B., R.Z., M.J.E. and E.G. performed in vivo experiments with S. aureus. D.R.N., S.G. and L.B.-M. performed in vivo experiments with S. pneumoniae. K.M. and J.S. provided bacterial culture supernatants for the in vitro experiments; J.S. performed MBC experiments; B.K. and L.J. performed bio-distribution experiments. M.L., H.W., A.D. and E.B.B. performed in vitro experiments; E.G. and A.K. designed the in vivo experiments with S. aureus and S. pneumoniae, respectively, and provided bacterial culture supernatants for the in vitro experiments. A.K. provided purified pneumolysin for in vitro experiments. E.B.B. designed the in vitro experiments. A.S. provided statistical advice for the paper. A.D. designed the study. E.B.B. designed and coordinated the study and wrote the paper. D.R.N., E.G., A.S., A.K. and A.D. edited and contributed to the writing of the paper. All authors analyzed and discussed the results and commented on the manuscript. E.G., A.K., A.D. and E.B.B. are co-senior authors.

Competing interests

E.B.B. and A.D. are inventors on a patent application pertaining to this work.

Corresponding author

Correspondence to Eduard B Babiychuk.

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DOI

https://doi.org/10.1038/nbt.3037

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