title: LEAP-2, LL-37 and RNase7 in tonsillar tissue: downregulated expression in seasonal allergic rhinitis.
abstract: In the upper airway, the production of antimicrobial peptides (AMPs) protects against bacteria, viruses and fungi. Previous investigations have revealed downregulated expression of AMPs in different manifestations of allergic disease. In this study, we examined the expression of LL-37, Ribonuclease7 (RNase7) and Liver-expressed antimicrobial peptide 2 (LEAP-2) in tonsillar tissue and studied a possible relation to seasonal allergic rhinitis (SAR). Tonsils, obtained from patients with SAR and nonallergic controls, were examined for the occurrence of LL-37, RNase7 and LEAP-2 with real-time RT-PCR and immunohistochemistry. Tonsillar mononuclear cells were cultured in presence or absence of LEAP-2 or LL-37 and analyzed for cytokine levels using ELISA. mRNA and protein for LL-37, RNase 7 and LEAP-2 were found in all tonsils. Immunohistochemistry revealed prominent staining for LL-37 and RNase7 in the tonsillar epithelium, whereas a moderate staining was seen with LEAP-2. Real-time RT-PCR showed a downregulation of RNase7 and LEAP-2 in the allergic as compared to the nonallergic group. Mononuclear cells cultured in presence of LEAP-2 or LL-37 demonstrated reduced levels of IL-10. The present study demonstrates the presence and function of LEAP-2, LL-37 and RNase7 in tonsils. Moreover, a downregulation of LEAP-2 and RNase7 is seen in SAR patients, indicating that allergic individuals may be more susceptible to respiratory tract infections due to an impaired antimicrobial defense.
authors.affiliation: Laboratory of Clinical and Experimental Allergy Research, Department of Otorhinolaryngology, Skånes University Hospital, Lund University, Malmö, Sweden.
authors.forename: Jesper
authors.initials: J
authors.lastname: Bogefors
authors.forename: Anne Månsson
authors.initials: AM
authors.lastname: Kvarnhammar
authors.forename: Camilla Rydberg
authors.initials: CR
authors.lastname: Millrud
authors.forename: Susanna Kumlien
authors.initials: SK
authors.lastname: Georén
authors.forename: Lars Olaf
authors.initials: LO
authors.lastname: Cardell
mesh_terms: D000293:Adolescent; D000328:Adult; D023181:Antimicrobial Cationic Peptides / Q000032:analysis*; D001798:Blood Proteins / Q000032:analysis*; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D016207:Cytokines / Q000378:metabolism; D015536:Down-Regulation; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D007150:Immunohistochemistry; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008297:Male; D014066:Palatine Tonsil / Q000473:pathology*; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D006255:Rhinitis, Allergic, Seasonal / Q000473:pathology*; D012260:Ribonucleases / Q000032:analysis*; D055815:Young Adult; D054804:Cathelicidins
chemical_list: D023181:Antimicrobial Cationic Peptides; D001798:Blood Proteins; D016207:Cytokines; C475606:liver-expressed antimicrobial peptide 2, human; D012260:Ribonucleases; C470000:Ribonuclease 7; D054804:Cathelicidins
keywords: allergy; antimicrobial peptides; innate immunity; upper airways