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Sarcoidosis is a granulomatous disorder of unknown etiology. Infection, genetic factors, autoimmunity and an aberrant innate immune system have been explored as potential causes of sarcoidosis. The etiology of sarcoidosis remains unknown, and it is thought that it might be caused by an infectious agent in a genetically predisposed, susceptible host. Inflammation results from recognition of evolutionarily conserved structures of pathogens (Pathogen-associated molecular patterns, PAMPs) and/or from reaction to tissue damage associated patterns (DAMPs) through recognition by a limited number of germ line-encoded pattern recognition receptors (PRRs). Due to the similar clinical and histopathological picture of sarcoidosis and tuberculosis, Mycobacterium tuberculosis antigens such early secreted antigen (ESAT-6), heat shock proteins (Mtb-HSP), catalase-peroxidase (katG) enzyme and superoxide dismutase A peptide (sodA) have been often considered as factors in the etiopathogenesis of sarcoidosis. Potential non-TB-associated PAMPs include lipopolysaccharide (LPS) from the outer membrane of Gram-negative bacteria, peptidoglycan, lipoteichoic acid, bacterial DNA, viral DNA/RNA, chitin, flagellin, leucine-rich repeats (LRR), mannans in the yeast cell wall, and microbial HSPs. Furthermore, exogenous non-organic antigens such as metals, silica, pigments with/without aluminum in tattoos, pesticides, and pollen have been evoked as potential causes of sarcoidosis. Exposure of the airways to diverse infectious and non-infectious agents may be important in the pathogenesis of sarcoidosis. The current review provides and update on the role of PPRs and DAMPs in the pathogenesis of sarcoidsis., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Inflammation is an important component of numerous cancers and chronic diseases and many inflammatory mediators have been shown to have potential prognostic roles. Tumor-infiltrating mast cells can promote tumor growth and angiogenesis, but the mechanism of mast cell activation is unclear. Early studies have shown that immunoglobulin free light chains (FLC) can trigger mast cell activation in an antigen-specific manner. Increased expression of FLC is observed within the stroma of many human cancers including those of breast, colon, lung, pancreas, kidney, and skin. These overexpressed FLCs are co-localized to areas of mast cell infiltration. Importantly, FLC expression is associated with basal-like cancers with an aggressive phenotype. Moreover, FLC is expressed in areas of inflammatory cell infiltration and its expression is significantly associated with poor clinical outcome. In addition, serum and bronchoalveolar fluid FLC concentrations are increased in patients with idiopathic pulmonary fibrosis (IPF) and hypersensitivity pneumonitis (HP) compared to control subjects. In this review, we provide an update on the role of FLC in the pathogenesis of several lung disorders and indicate how this may contribute to new therapeutic opportunities.

MicroRNAs (miRNAs) are small non-coding RNAs which can act as master regulators of gene expression, modulate almost all biological process and are essential for maintaining cellular homeostasis. Dysregulation of miRNA expression has been associated with aberrant gene expression and may lead to pathological conditions. Evidence suggests that miRNA expression profiles are altered between health and disease and as such may be considered as biomarkers of disease. Evidence is increasing that miRNAs are particularly important in lung homeostasis and development and have been demonstrated to be the involved in many pulmonary diseases such as asthma, COPD, sarcoidosis, lung cancer and other smoking related diseases. Better understanding of the function of miRNA and the mechanisms underlying their action in the lung, would help to improve current diagnosis and therapeutics strategies in pulmonary diseases. Recently, some miRNA-based drugs have been introduced as possible therapeutic agents. In this review we aim to summarize the recent findings regarding the role of miRNAs in the airways and lung and emphasise their potential therapeutic roles in pulmonary diseases., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Innate lymphoid cells (ILCs) are identified as novel population of hematopoietic cells which protect the body by coordinating the innate immune response against a wide range of threats including infections, tissue damages and homeostatic disturbances. ILCs, particularly ILC2 cells, are found throughout the body including the brain. ILCs are morphologically similar to lymphocytes, express and release high levels of T-helper (Th)1, Th2 and Th17 cytokines but do not express classical cell-surface markers that are associated with other immune cell lineages. Three types of ILCs (ILC1, 2 & 3) have been reported depending upon the cytokines produced. ILC1 cells encompass natural killer (NK) cells and interferon (IFN)-g releasing cells; ILC2 cells release the Th2 cytokines, IL-5, IL-9 and IL-13 in response to IL-25 and IL-33; and ILC3 cells which release IL-17 and IL-22. ILC2 cells have been implicated inmucosal reactions occurring in animal models of allergic asthma and virus-induced lung disorders resulting in the regulation of airway remodeling and tissue homeostasis. There is evidence for increased ILC2 cell numbers in allergic responses in man but little is known about the role of ILCs in chronic obstructive pulmonary disease (COPD). Further understanding of the characteristics of ILCs such as their origin, location and phenotypes and function would help to clarify the role of these cells in the pathogenesis of various lung diseases. In this review we will focus on the role of ILC2 cells and consider their origin, function,location and possible role in the pathogenesis of the chronic inflammatory disorders such as asthma and COPD.

The use of flow cytometry in the clinical laboratory has grown substantially in the past decade. Flow cytometric analysis provides a rapid qualitative and quantitative description of multiple characteristics of individual cells. For example, it is possible to detect the cell size and granularity, aspects of DNA and RNA content and the presence of cell surface and nuclear markers which are used to characterize the phenotype of single cells. Flow cytometry has been used for the immunophenotyping of a variety of specimens including whole blood, bone marrow, serous cavity fluids, (cerebrospinal fluid) CSF, urine and all types of body fluids. The technique has also been applied to human bronchoalveolar lavage (BAL) fluid, peritoneal fluids and blood. In this review, we describe the current status of the application of flow cytometry as a diagnostic tool in various lung diseases. We focus on the analysis of BAL cell composition in chronic obstructive lung disease (COPD), asthma, lung cancer, sarcoidosis, tuberculosis and idiopathic eosinophilic pneumonia (IEP).

Asthma and Chronic Obstructive Pulmonary Disease (COPD) are two important lung and airways diseases which affect the lives of ∼500 million people worldwide. Asthma is a heterogeneous disease that is broadly defined as a clinical syndrome characterized by altered lung function, mucus hypersecretion, peribronchial inflammation and hyperresponsiveness In contrast, the effect of inhalation of toxic particles and gases on the innate and adaptive inflammatory immune systems underlie the pathogenesis of COPD. In the last decade, knowledge concerning the pathophysiologic mechanisms underlying asthma and COPD has risen tremendously and current dogma suggests that the pathogenesis of both diseases is driven by the chronic inflammation present in the airways of these patients. Thus, understanding the mechanisms for the persistence of inflammation may lead to new therapeutic approaches. In this review, we provide an overview of the main signal transduction pathways implicated in asthma and COPD pathophysiology focusing on inflammasome signaling in various cells types which result in altered inflammatory mediator expression.

Background: Although lung transplantation is a well-accepted treatment for end-stage lung diseases patients, only 15%-20% of the brain-dead donors' lungs are usable for transplantation. This results in high mortality of candidates on waiting lists. Ex-vivo lung perfusion (EVLP) is a novel method for better evaluation of a potential lung for transplantation. Objective: To report the first experience of EVLP in Iran. Methods: The study included a pig in Vienna Medical University, Vienna, Austria, and 4 humans in Masih Daneshvari Hospital, Tehran, Iran. All brain-dead donors from 2013 to 2015 in Tehran were evaluated for EVLP. Donors without signs of severe chest trauma or pneumonia, with poor oxygenation were included. Results: An increasing trend in difference between the pulmonary arterial pO2 and left atrial pO2, an increasing pattern in dynamic lung compliance, and a decreasing trend in the pulmonary vascular resistance, were observed. Conclusion: The initial experience of EVLP in Iran was successful in terms of important/critical parameters. The results emphasize on some important considerations such as precisely following standard lung harvesting and monitoring temperature and pressure. EVLP technique may not be a cost-effective option for low-income countries at first glance. However, because this is the only therapeutic treatment for endstage lung disease, it is advisable to continue working on this method to find alternatives with lesser costs. [ABSTRACT FROM AUTHOR]

Background Mast cells are important effector cells in innate or acquired immunity that contribute to host defence. Excessive activation of mast cells can result in the development of allergic diseases, including atopic asthma. Mast cell activation by IgE and specific antigen induces the cells to release spasmogenic, vasoactive and pro-inflammatory mediators, which enhance airway smooth muscle contraction, vascular permeability and inflammatory cell recruitment. Recently, we have demonstrated that exposure of mast cells to cigarette smoke medium (CSM) triggered mast cells to produce chemokines. On the other hand, smoking may decrease the risk of allergic sensitization, which could be explained by a reduced IgE production or a diminished response of mast cells to activation of the IgE receptor. Objective In this study, we investigated the effect of CSM on the allergic activation of mast cells through IgE and antigen. Methods Primary cultured murine mast cells were exposed to CSM and activated with IgE and antigen or lipopolysaccharide (LPS). The release of granules, production of leukotrienes, chemokines and cytokines was determined in the supernatants by ELISA. The effect of CSM exposure on intracellular signalling, especially the nuclear factor (NF)-κB and extracellular signal-regulated kinase (Erk)1/2 pathways, was analysed by Western blotting. Results CSM suppressed IgE-mediated degranulation and cytokine release, but no effect was observed on leukotriene release. CSM induced phosphorylation of Erk1/2 in mast cells. In CSM-exposed mast cells, activating transcription factor (ATF)-1 was phosphorylated after stimulation with IgE/Ag. LPS-activated mast cells were not influenced by CSM. Conclusion Our study suggests that exposure to cigarette smoke may lead to a reduced allergic activation of mast cells without affecting their response to activation via e.g. bacterial-derived LPS. [ABSTRACT FROM AUTHOR]