title: Mast cells determine the magnitude of bacterial toxin-induced skin inflammation.
abstract: Mast cells are known to be important effector cells in innate immune responses to bacterial infections. However, up to now, neither the mechanisms nor the relevance of mast cell degranulation in innate skin immune responses to bacteria have been adequately addressed. In this article, we show that the bacterial toxins streptolysin O (SLO) and alpha-toxin potently induce degranulation of mast cells in vitro and in vivo. Furthermore, intradermal injection of the toxins results in pronounced skin inflammation, which either resolves quickly within a few h (SLO-induced inflammation) or presents a chronic process with ongoing inflammation for weeks (alpha-toxin). Interestingly, mast cells mediated the inflammatory effects of SLO, but in contrast limited inflammatory skin responses to alpha-toxin. These findings further support the hypothesis that mast cells are critically involved in initiating and modulating optimal host responses to bacteria by either inflammatory or anti-inflammatory effects, depending on the course of the host reaction induced by the pathogen.
authors.affiliation: Department of Dermatology and Allergy, Allergie-Centrum-Charité, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Metz
authors.forename: Markus
authors.initials: M
authors.lastname: Magerl
authors.forename: Nele F
authors.initials: NF
authors.lastname: Kühl
authors.forename: Angela
authors.initials: A
authors.lastname: Valeva
authors.forename: Sucharit
authors.initials: S
authors.lastname: Bhakdi
authors.forename: Marcus
authors.initials: M
authors.lastname: Maurer
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology; D001427:Bacterial Toxins / Q000008:administration & dosage / Q000009:adverse effects* / Q000494:pharmacology; D003872:Dermatitis / Q000382:microbiology* / Q000473:pathology*; D004195:Disease Models, Animal; D006460:Hemolysin Proteins / Q000008:administration & dosage / Q000009:adverse effects* / Q000494:pharmacology; D007107:Immune System / Q000502:physiology; D007271:Injections, Intradermal; D008407:Mast Cells / Q000187:drug effects / Q000473:pathology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D010537:Peritoneum / Q000473:pathology; D012720:Severity of Illness Index; D013203:Staphylococcal Infections / Q000276:immunology / Q000473:pathology; D013211:Staphylococcus aureus; D013290:Streptococcal Infections / Q000276:immunology / Q000473:pathology; D013297:Streptococcus pyogenes; D013301:Streptolysins / Q000008:administration & dosage / Q000009:adverse effects* / Q000494:pharmacology
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D006460:Hemolysin Proteins; D013301:Streptolysins; C021091:staphylococcal alpha-toxin; C025964:streptolysin O