Purpose: Smoking is a risk factor for the development of asthma and worsens the long-term prognosis of asthma. This study investigated the effect of cigarette smoke extract (CSE) on innate immune cells such as innate lymphoid cells (ILCs) and macrophages in a murine model of induced asthma. Methods: Six-week-old female BALB/C mice were exposed to ovalbumin (OVA) via an intranasal route with or without CSE for 8 weeks to establish a chronic murine asthma model. Airway hyperresponsiveness (AHR), airway inflammatory cells from bronchoalveolar lavage fluid, and the population of CD4 + T cells, ILCs, and macrophages in the lungs were studied to evaluate the effect of chronic CSE exposure on asthma. Results: Mice intranasally exposed to CSE along with OVA treatment (CSE/OVA) had significantly enhanced AHR, eosinophilic inflammation, increased IL-13 and IL-17 producing CD4 + T cells compared to mice intranasally exposed to OVA only. On the contrary, the frequency of Foxp3 + in CD4 + T cells was reduced in the CSE/OVA group. CSE enhanced the dendritic cell (DC) population, especially MHCII + DC with antigen-presenting capacity. Among ILCs, the CSE/OVA group showed a significant increase of IL-13-producing type 2 ILCs, but not interferon-γ+ ILC1s and IL-17 + ILC3s. . Among macrophages, alveolar macrophage and Ym-1 and FIZZ1 positive M2 macrophage populations were significantly induced by CSE exposure alone and when combined with OVA treatment. Conclusion In this study, we showed that long-term exposure to cigarette smoke contributes to the inception and aggravation of asthmatic inflammation by enhancing DCs, ILC2, and M2 alveolar macrophage populations in the mouse model.

Background: Digital pathology (DP) using whole slide imaging is a recently emerging game changer technology that can fundamentally change the way of working in pathology. The Digital Pathology Study Group (DPSG) of the Korean Society of Pathologists (KSP) published a consensus report on the recommendations for pathologic practice using DP. Accordingly, the need for the development and implementation of a quality assurance program (QAP) for DP has been raised. Methods: To provide a standard baseline reference for internal and external QAP for DP, the members of the Committee of Quality Assurance of the KSP developed a checklist for the Redbook and a QAP trial for DP based on the prior DPSG consensus report. Four leading institutes participated in the QAP trial in the first year, and we gathered feedback from these institutes afterwards. Results: The newly developed checklists of QAP for DP contain 39 items (216 score): eight items for quality control of DP systems; three for DP personnel; nine for hardware and software requirements for DP systems; 15 for validation, operation, and management of DP systems; and four for data security and personal information protection. Most participants in the QAP trial replied that continuous education on unfamiliar terminology and more practical experience is demanding. Conclusions The QAP for DP is essential for the safe implementation of DP in pathologic practice. Each laboratory should prepare an institutional QAP according to this checklist, and consecutive revision of the checklist with feedback from the QAP trial for DP needs to follow.

Purpose: Asthma is a chronic airway inflammatory disorder and is associated with macrophages. Statin, a well-known lipid-lowering agent, has recently been noted for its anti-inflammatory effect on macrophage. This study was designed to evaluate the antiasthmatic effect of atorvastatin via modulation of macrophage activation by using an animal model of allergic asthma. Methods: Atorvastatin 40 mg/kg was given by gavage once a day for 3 days before challenge of ovalbumin (OVA); airway hyperresponsiveness (AHR), airway inflammatory cells, and cytokines were evaluated in the murine asthma model. The direct effect of atorvastatin on the activation of macrophages In vitro was determined using the alveolar macrophage cell line CRL-2456. Results: Administration of atorvastatin reduced the numbers of total inflammatory cells, macrophages, and eosinophils as well as lung histology enhanced in the murine asthma model. AHR measured by enhanced pause was significantly reduced after atorvastatin administration in the murine asthma model (P< 0.05). Atorvastatin administration resulted in the reduction in serum OVA-specific IgE levels and the increase in serum OVA-specific IgG2a levels (P< 0.05). The mRNA levels of Ccr3, Il-17, and Muc5ac enhanced by OVA challenge were decreased by treatment with atorvastatin (P< 0.05). Along with these improvement in allergic inflammatory changes, the population of CD11c-CD206+ macrophages as well as the expression of Ym-1 and Relm-α in the lungs were reduced with atorvastatin (P< 0.05). In vitro test with CRL-2456 showed that atorvastatin reduced the expression of Cd206, Arg-1, and Fgf-2 induced by IL-4 stimulation (P< 0.05). Conclusion This study highlighted the antiasthmatic effect of atorvastatin on the suppression of M2 macrophage activation in allergic asthma.

Purpose: Asthma is a common chronic lung disease, in which interleukin (IL)-13 is implicated as a central regulator of IgE synthesis, mucus hypersecretion, airway hyperresponsiveness (AHR), and fibrosis. This study was designed to determine the anti-inflammatory effect of atorvastatin, a widely used lipid-lowering agent, on the IL-13-induced lung pathology through the modulation of macrophages. Methods: Atorvastatin (40 mg/kg) was given to transgenic mice overexpressing IL-13 (IL-13 TG mice) and their wild type littermates by oral gavage for 2 weeks. AHR, numbers of inflammatory cells in the airway, and cytokine levels in IL-13 TG mice were measured.Using the alveolar macrophage cell line CRL-2456, the direct effect of atorvastatin on macrophages activated by recombinant IL-13 was assessed. Results: Significant reduction in total leukocytes and alleviation of AHR were observed with administration of atorvastatin in IL-13 TG mice compared to those without atorvastatin treatment (P< 0.05). Atorvastatin administration resulted in upregulation of IL-10 in the lungs of IL-13 TG mice (P< 0.05). In addition, mRNA expression of connective tissue growth factor, fibronectin, and type III collagen as well as chord length enhanced by IL-13 overexpression were reduced by atorvastatin administration (P< 0.05). M2 macrophage markers, such as Ym-1 and CD206, were decreased, while M1 macrophage marker, inducible nitric oxide synthase, was increased upon atorvastatin treatment (P< 0.05). Administration of atorvastatin resulted in improved removal of apoptotic cells (P< 0.05). Conclusion The results of this study reveal a potential of atorvastatin as an effective antiasthmatic agent by reducing IL-13-induced lung inflammation via the modulation of macrophage polarization.

Mesenchymal stem cells (MSCs) are attractive alternatives to conventional anti-asthmatic drugs for severe asthma. Mechanisms underlying the anti-asthmatic effects of MSCs have not yet been elucidated. This study evaluated the anti-asthmatic effects of intravenously administered MSCs, focusing on macrophages and monocytes. Seven-week-old transgenic (Tg) mice with lung-specific overexpression of IL-13 were used to simulate chronic asthma.MSCs were intravenously administered four days before sampling. We examined changes in immune cell subpopulations, gene expression, and histological phenotypes. IL-13 Tg mice exhibited diverse features of chronic asthma, including severe type 2 inflammation, airway fibrosis, and mucus metaplasia. Intravenous administration of MSCs attenuated these asthmatic features just four days after a single treatment. MSC treatment significantly reduced SiglecF - CD11c - CD11b + monocyte-derived macrophages (MoMs) and inhibited the polarization of MoMs into M2 macrophages, especially M2a and M2c. Furthermore, MSCs downregulated the excessive accumulation of Ly6c - monocytes in the lungs. While an intravenous adoptive transfer of Ly6c - monocytes promoted the infiltration of MoM and Th2 inflammation, that of MSC-exposed Ly6c - monocytes did not. Ex vivo Ly6c - MoMs upregulated M2-related genes, which were reduced by MSC treatment. Molecules secreted by Ly6c - MoMs from IL-13 Tg mice lungs upregulated the expression of fibrosis-related genes in fibroblasts, which were also suppressed by MSC treatment. In conclusion, intravenously administered MSCs attenuate asthma phenotypes of chronic asthma by modulating macrophages. Identifying M2 macrophage subtypes revealed that exposure to MSCs transforms the phenotype and function of macrophages. We suggest that Ly6c - monocytes could be a therapeutic target for asthma management.