title: The host defense peptide cathelicidin is required for NK cell-mediated suppression of tumor growth.
abstract: Tumor surveillance requires the interaction of multiple molecules and cells that participate in innate and the adaptive immunity. Cathelicidin was initially identified as an antimicrobial peptide, although it is now clear that it fulfills a variety of immune functions beyond microbial killing. Recent data have suggested contrasting roles for cathelicidin in tumor development. Because its role in tumor surveillance is not well understood, we investigated the requirement of cathelicidin in controlling transplantable tumors in mice. Cathelicidin was observed to be abundant in tumor-infiltrating NK1.1(+) cells in mice. The importance of this finding was demonstrated by the fact that cathelicidin knockout mice (Camp(-/-)) permitted faster tumor growth than wild type controls in two different xenograft tumor mouse models (B16.F10 and RMA-S). Functional in vitro analyses found that NK cells derived from Camp(-/-) versus wild type mice showed impaired cytotoxic activity toward tumor targets. These findings could not be solely attributed to an observed perforin deficiency in freshly isolated Camp(-/-) NK cells, because this deficiency could be partially restored by IL-2 treatment, whereas cytotoxic activity was still defective in IL-2-activated Camp(-/-) NK cells. Thus, we demonstrate a previously unrecognized role of cathelicidin in NK cell antitumor function.
authors: Division of Dermatology, Department of Medicine, University of California San Diego, La Jolla, CA 92093, USA.
authors: Amanda S
authors: AS
authors: Büchau
authors: Shin
authors: S
authors: Morizane
authors: Janet
authors: J
authors: Trowbridge
authors: Jürgen
authors: J
authors: Schauber
authors: Paul
authors: P
authors: Kotol
authors: Jack D
authors: JD
authors: Bui
authors: Richard L
authors: RL
authors: Gallo
mesh_terms: D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics / Q000276:immunology*; D015153:Blotting, Western; D005455:Fluorescent Antibody Technique; D006801:Humans; D007150:Immunohistochemistry; D007157:Immunologic Surveillance / Q000276:immunology*; D007694:Killer Cells, Natural / Q000276:immunology*; D008546:Melanoma, Experimental / Q000276:immunology*; D051379:Mice; D018345:Mice, Knockout; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D023041:Xenograft Model Antitumor Assays; D054804:Cathelicidins
chemical_list: D023181:Antimicrobial Cationic Peptides; D054804:Cathelicidins