Identification of bacterial biofilm and the Staphylococcus aureus derived protease, staphopain, on the skin surface of patients with atopic dermatitis

• Published in: Scientific reports 2017-08, Vol.7 (1), p.8689-12, Article 8689
• Main Authors: Sonesson, Andreas, Przybyszewska, Kornelia, Eriksson, Sigrid, Mörgelin, Matthias, Kjellström, Sven, Davies, Julia, Potempa, Jan, Schmidtchen, Artur
• Format: Article
• Language: English
• Subjects: 101/1; 14/19; 14/34; 692/699/255/1318; 692/699/4033; 82/29; 82/58; Adaptive immunity; Adult; Amino Acid Sequence; Anti-Bacterial Agents - pharmacology; Atopic dermatitis; Bacteria; Basic Medicine; Biodegradation; Biofilms; Biofilms - drug effects; Cathelicidins - pharmacology; Clinical Medicine; Colonization; Confocal microscopy; Cysteine Endopeptidases - pharmacology; Degradation products; Dermatitis; Dermatitis, Atopic - microbiology; Dermatologi och venereologi; Dermatology and Venereal Diseases; Eczema; Electron microscopy; Humanities and Social Sciences; Humans; infection; Infectious Medicine; Infektionsmedicin; Klinisk medicin; Läkemedelskemi; Medical and Health Sciences; Medicin och hälsovetenskap; Medicinal Chemistry; Medicinska och farmaceutiska grundvetenskaper; Microbial Sensitivity Tests; multidisciplinary; Peptide Fragments - chemistry; Peptide Fragments - pharmacology; Planktonic cells; Proteinase; Science; Science (multidisciplinary); Skin; Skin - microbiology; Skin - pathology; Skin diseases; Staphopain; Staphylococcus aureus; Staphylococcus aureus - drug effects; Staphylococcus aureus - physiology; Staphylococcus aureus - ultrastructure
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-017-08046-2

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by an impaired epidermal barrier, dysregulation of innate and adaptive immunity, and a high susceptibility to bacterial colonization and infection. In the present study, bacterial biofilm was visualized by electron microscopy at the surface of AD skin. Correspondingly, Staphylococcus aureus ( S . aureus ) isolates from lesional skin of patients with AD, produced a substantial amount of biofilm in vitro . S . aureus biofilms showed less susceptibility to killing by the antimicrobial peptide LL-37 when compared with results obtained using planktonic cells. Confocal microscopy analysis showed that LL-37 binds to the S . aureus biofilms. Immuno-gold staining of S . aureus biofilm of AD skin detected the S . aureus derived protease staphopain adjacent to the bacteria. In vitro , staphopain B degraded LL-37 into shorter peptide fragments. Further, LL-37 significantly inhibited S . aureus biofilm formation, but no such effects were observed for the degradation products. The data presented here provide novel information on staphopains present in S . aureus biofilms in vivo , and illustrate the complex interplay between biofilm and LL-37 in skin of AD patients, possibly leading to a disturbed host defense, which facilitates bacterial persistence.