Assays for Identifying Inducers of the Antimicrobial Peptide LL-37

  • Frank Nylén
  • Peter Bergman
  • Gudmundur H. Gudmundsson
  • Birgitta Agerberth
Part of the Methods in Molecular Biology book series (MIMB, volume 1548)


One promising approach to meet the growing problem of antibiotic resistance is to modulate host defense mechanisms, i.e., host-directed therapy (HDT), in the fight against infections. Induction of endogenous antimicrobial peptides (AMPs) via small molecular compounds, such as 1,25-dihydroxyvitamin D3 or phenylbutyrate, could provide one such HDT-based approach.

We have developed a cell-based screening assay for the identification of novel compounds with the capacity to induce AMP expression and here follows the detailed protocol.

Key words

Chemical library screening CAMP gene Z′-factor Cell-based reporter system 



We are grateful to Hanna Axelsson, at CBCS and Karolinska Institutet, for discussions and advice regarding assay formatting and data analysis.

“The authors are supported by the Swedish Research Council (56X-1217-01-6 (BA), 20854 (BA) and 2013-2709 (PB), a Linneus grant CERIC, BA), The Swedish Strategic Foundation: RBd08-0014 (BA), Karolinska Institutet (BA, PB), the Icelandic Centre for Research (RANNIS, GHG), and the University of Iceland Research Fund (GHG). Groschinsky's Foundation (PB), Scandinavian Society for Antimicrobial Therapy Foundation (PB), Swedish Society of Physicians (PB), and Heart and Lung Foundation (BA, PB).

Gudmundur H. Gudmundsson is a visiting scientist at Karolinska Institutet supported by the Wenner-Gren foundation. The Prestwick Chemical Library and plating thereof was provided by the Chemical Biology Consortium Sweden (CBCS).


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Copyright information

© Springer Science+Business Media LLC 2017

Authors and Affiliations

  • Frank Nylén
    • 1
  • Peter Bergman
    • 1
  • Gudmundur H. Gudmundsson
    • 2
  • Birgitta Agerberth
    • 1
  1. 1.Department of Laboratory MedicineKarolinska InstitutetHuddingeSweden
  2. 2.Institute of Biology and Biomedical CenterUniversity of IcelandReykjavíkIceland

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