Charcot leyden crystals

• Diagnostic features: eosinophilic mucin with red and blue ripples (laminations composed of cellular debris, epithelium, polymorphonuclear cells, degranulated eosinophils and Charcot Leyden crystals) • Charcot Leyden crystals are pink/red refractive, and form long needle-like structures • Rare noninvasive fungal hyphae (often found only with GMS stain) • Schneiderian mucosa reveals thickened basement membrane with goblet cell hyperplasia, and numerous inflammatory cells with prominent eosinophils • Eosinophils may have degenerative changes of smudged, elongated or basophilic nuclei • It is unclear if eosinophilic mucin rhinosinusitis (EMRS) is a distinct entity from allergic fungal sinusitis (AFS) because: • Fungal hyphae are not always detected in allergic mucin, although the sensitivity for fungal detection by the gold standard Gomori methanamine silver (GMS) stain is dramatically improved by trypsin predigestion, which speaks against EMRS as a distinct entity • On the other hand, aspirin sensitivity and bilateral sinus disease are more common types of eosinophilic mucin rhinosinusitis than allergic fungal sinusitis, consistent with the idea that ERMS represents a distinct clinical entity • Thus, this issue remains unresolved

B.S.F. is supported by a grant from the European Research Council (PLAT-IL-1), the German Research Foundation (DFG) (SFBTRR57), and BONFOR. B.S.F., E.L., and N.G. are members of the ImmunoSensation Cluster of Excellence. N.G. is supported by grants from the DFG (SFB704 and GRK2168). E.L. is supported by grants from the DFG (SFB645, 704, 670, 1123, TRR57, 83) and the European Research Council (InflammAct). Citation Juan Francisco Rodríguez-Alcázar , Marco Antonio Ataide , Gudrun Engels , Christine Schmitt-Mabmunyo , Natalio Garbi , Wolfgang Kastenmüller , Eicke Latz , Bernardo S. Franklin; Charcot–Leyden Crystals Activate the NLRP3 Inflammasome and Cause IL-1β Inflammation in Human Macrophages. J Immunol 15 January 2019; 202 (2): 550–558. Download citation file: • • • • • • • • • Charcot–Leyden crystals (CLCs) are Galectin-10 protein crystals that can form after eosinophils degranulate. CLCs can appear and persist in tissues from patients with eosinophilic disorders, such as asthma, allergic reactions, and fungal and helminthic infections. Despite abundant reports of their occurrence in human disease, the inflammatory potential of CLCs has remained unknown. In this article, we show that CLCs induce the release of the proinflammatory cytokine IL-1β upon their phagocytosis by primary human macrophages in vitro. Chemical inhibition and small interfering RNA knockdown of NLRP3 in primary human macrophages abrogated their IL-1β response to CLCs. Using C57BL/6 ASC-mCitrine transg...