Charcot‐Leyden crystals in tissues

To the Editor, We read with interest paper by Chen et al. entitled “Predictive significance of Charcot-Leyden crystal (CLC) structures for nasal polyp recurrence”.1 CLCs are formed when galectin-10 crystallizes intracellularly or extracellularly through eosinophil ETosis, an active cell death process involving disruption nucleus and plasma membrane to release web-like chromatin structures.2, 3 Intact granules also released during this process, typically characterized presence cell-free (Cfegs).2 In H&E-stained specimens shown al., most eosinophils in tissues have barely retained their morphology, both nuclear contents Cfegs clearly visible. Meanwhile, lack concordance between counts may arisen because cytolytic not evaluated.4 Not only cytotoxic granule proteins ETosis but crystals themselves enhance exacerbation loop inflammation.5 Therefore, it is significant focus on tissues. previously examined histology patients eosinophilic chronic rhinosinusitis found that were present more than half moderate severe disease based JESREC criteria.6 study, recurrence rates 31.1% 51.8% disease.6 These findings generally consistent results Nasal polyps clinically easy obtain examination, pathologists should be encouraged report clinicians. However, there several associated problems. First, tissue sections uniform can differ markedly depending field observed. Second, angle at which sectioned, characteristic needle-like difficult identify. Third, distinguish from other structures, including collagen fibers. As Figure 1, easily observed immunofluorescence staining galectin-10,3 a time-consuming labor-intensive process. been diseases, clinical has fully investigated. It will interesting determine whether similar trends diseases predict efficacy eosinophil-targeted therapies. The same section patient was evaluated (left) H&E (right) (green) DNA (blue). Abundant (CLCs) as galectin-10-positive structures. Written informed consent obtained accordance principles laid out Declaration Helsinki using Institutional Review Board-approved protocols. Tomoko Sasaki: Investigation (Equal); Validation Visualization (Equal). Isao Suzaki: Conceptualization Resources (Supporting). This work funded Ministry Education, Culture, Sports, Science Technology, Japan Society Promotion (20H03832, 20K08794, 21K07833, 21K08434). Shigeharu Ueki received grants honoraria lectures AstraZeneca, GlaxoSmithKline Sanofi, Novartis, VIB, Maruho Co. Ltd. Science, Grant/Award Numbers: 20H03832, 21K08434 Data available request authors.