title: What is new in the histogenesis of granulomatous skin diseases?
abstract: A granuloma is a form of inflammation, which predominantly consists of macrophages. It typically develops when the immune system attempts to enclose substances that are usually insoluble and cannot be eliminated to prevent the spread of these substances to the other body compartments. According to the source of the substances, granulomatous diseases can be divided into two groups: infectious and non-infectious. The mechanisms of infectious granuloma formation have been widely investigated because of its easy reproducibility in experimental models, both in vivo and in vitro. On the contrary, mechanisms of non-infectious granuloma formation have not been well investigated because of the difficulty to reproduce this formation in experimental models. In this article, we review our recent understanding of the histogenesis and pathogenesis of granuloma formation, confirmed from studies of infectious granulomas, and we present potential hypotheses of the histogenesis and pathogenesis of non-infectious granulomas based on clinical investigations.
authors.affiliation: Department of Dermatology, Kyoto prefectural University of Medicine, Graduate School of Medical Science, Kyoto, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Asai
mesh_terms: D003872:Dermatitis / Q000276:immunology / Q000473:pathology; D006099:Granuloma / Q000276:immunology / Q000473:pathology*; D016460:Granuloma Annulare / Q000276:immunology / Q000473:pathology; D006801:Humans; D008264:Macrophages / Q000276:immunology*; D009335:Necrobiosis Lipoidica / Q000276:immunology / Q000473:pathology; D012507:Sarcoidosis / Q000276:immunology / Q000473:pathology; D012871:Skin Diseases / Q000276:immunology / Q000473:pathology*
keywords: granuloma; granuloma annulare; macrophage polarization; necrobiosis lipoidica; sarcoidosis