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The article presents a study on the association of fractional exhaled nitric oxide and blood eosinophils with inflammation observed in the sputum and blood compartments in severe asthma. Topics discussed include the prognostic information on the occurrence of severe asthma attacks being provided by fractional exhaled nitric oxide and the blood eosinophil, the methods used in the study, and limitations of the study.

Summary: Azithromycin (AZM) is a synthetic macrolide antibiotic effective against a broad range of bacterial and mycobacterial infections. Due to an additional range of anti‐viral and anti‐inflammatory properties, it has been given to patients with the coronaviruses SARS‐CoV or MERS‐CoV. It is now being investigated as a potential candidate treatment for SARS‐CoV‐2 having been identified as a candidate therapeutic for this virus by both in vitro and in silico drug screens. To date there are no randomised trial data on its use in any novel coronavirus infection, although a large number of trials are currently in progress. In this review, we summarise data from in vitro, murine and human clinical studies on the anti‐viral and anti‐inflammatory properties of macrolides, particularly AZM. AZM reduces in vitro replication of several classes of viruses including rhinovirus, influenza A, Zika virus, Ebola, enteroviruses and coronaviruses, via several mechanisms. AZM enhances expression of anti‐viral pattern recognition receptors and induction of anti‐viral type I and III interferon responses. Of relevance to severe coronavirus‐19 disease (COVID‐19), which is characterised by an over‐exuberant innate inflammatory response, AZM also has anti‐inflammatory properties including suppression of IL‐1beta, IL‐2, TNF and GM‐CSF. AZM inhibits T cells by inhibiting calcineurin signalling, mammalian target of rapamycin activity and NFκB activation. AZM particularly targets granulocytes where it concentrates markedly in lysosomes, particularly affecting accumulation, adhesion, degranulation and apoptosis of neutrophils. Given its proven safety, affordability and global availability, tempered by significant concerns about antimicrobial stewardship, there is an urgent mandate to perform well‐designed and conducted randomised clinical trials. [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a new rapidly spreading infectious disease. Current guidance from the World Health Organization (WHO) highlights asthmatics as a high-risk group for severe illness from COVID-19. Viruses are common triggers of asthma exacerbations and the current SARS-CoV-2 pandemic raises several questions regarding the optimum management strategies. Here, we discuss the contentious issue of whether the mainstay therapy systemic corticosteroids should be used in the routine management of COVID-19-associated asthma exacerbations. Recent guidance from the WHO has advised against the use of corticosteroids if COVID-19 is suspected due to concerns that these agents may impair protective innate antiviral immune responses. This may not be appropriate in the unique case of asthma exacerbation, a syndrome associated with augmented type 2 inflammation, a disease feature that is known to directly inhibit antiviral immunity. Corticosteroids, through their suppressive effects on type 2 inflammation, are thus likely to restore impaired antiviral immunity in asthma and, in contrast to non-asthmatic subjects, have beneficial clinical effects in the context of SARS-CoV-2 infection. [ABSTRACT FROM AUTHOR]

Dupilumab shows improvement in validated disease specific quality of life scores compared with placebo Larger studies are needed to improve the certainty of evidence for Omalizumab and Mepolizumab Further data on longer term outcomes, cost effectiveness and those with less severe disease are needed Chronic rhinosinusitis (CRS) refers to inflammation of the nasal sinuses and mucosa, with persistence of sinus inflammation and clinical manifestations beyond 12 weeks.1 CRS affects between 6 and 12% of adults and is a cause of reduced quality of life (QoL) and high healthcare costs.2 Management consisted of topical and systemic glucocorticoids, antibiotics and often repeated sinus surgery. The review found evidence of improvement in disease-specific health-related quality of life and disease severity for patients with severe CRSwNP treated with all three classes of biologics compared with placebo. [Extracted from the article]

A correction is presented to the article "COVID-19 related Genes in Sputum Cells in Asthma: Relationship to Demographic Features and Corticosteroids" which appeared in the July 1, 2020 issue.

The article informs that eosinophilic airway inflammation is present in approximately half of patients with asthma, and it is particularly associated with asthma attacks. Topics include the two anti– Interleukin 5 (IL5) monoclonal antibodies are licensed for use in asthma and can be administered subcutaneously are mepolizumab, and benralizumab; and both anti–IL-5 monoclonal antibodies have proven efficacy in decreasing the frequency of asthma exacerbations.

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Mucosal-associated invariant T ( MAIT) cells are a novel class of innate-like T cells, expressing a semi-invariant T-cell receptor ( TCR) and able to recognize small molecules presented on the non-polymorphic MHC-related protein 1. Their intrinsic effector-memory phenotype, enabling secretion of pro-inflammatory cytokines, and their relative abundance in humans imply a significant potential to contribute to autoimmune processes. However, as MAIT cells were unknown until recently and specific immunological tools were unavailable, little is known of their roles in disease. Here I review observations from clinical studies and animal models of autoimmune and immune-mediated diseases including the roles of MAIT cells in systemic lupus erythematosus, rheumatoid arthritis, multiple sclerosis, inflammatory bowel disease and airways diseases. MAIT cell deficiencies are frequently observed in peripheral blood, and at sites of disease such as the airways in asthma. However, MAIT cells have a specific sensitivity to suppression by therapeutic corticosteroids that may confound many of these observations, as may the tendency of the surface marker CD161 to activation-induced down-regulation. Nonetheless, the dependence on bacteria for the development of MAIT cells suggests a potentially important protective role linking the influences of early life microbial exposures and subsequent development of autoimmunity. Conversely, MAIT cells could contribute to chronic inflammation either through TCR-independent activation, or potentially by TCR recognition of as yet undiscovered ligands. Future research will be greatly facilitated by the immunological tools that are now available, including murine genetic models and human and murine specific tetramers. [ABSTRACT FROM AUTHOR]

We have previously shown that underground railway particulate matter (PM) is rich in iron and other transition metals across coarse (PM10-2.5), fine (PM2.5), and quasi-ultrafine (PM0.18) fractions and is able to generate reactive oxygen species (ROS). However, there is little knowledge of whether the metal-rich nature of such particles exerts toxic effects in mucus-covered airway epithelial cell cultures or whether there is an increased risk posed by the ultrafine fraction. Monolayer and mucociliary air-liquid interface (ALI) cultures of primary bronchial epithelial cells (PBECs) were exposed to size-fractionated underground railway PM (1.1-11.1 μg/cm2) and release of lactate dehydrogenase and IL-8 was assayed. ROS generation was measured, and the mechanism of generation studied using desferrioxamine (DFX) and N-acetylcysteine (NAC). Expression of heme oxygenase-1 (HO-1) was determined by RT-qPCR. Particle uptake was studied by transmission electron microscopy. Underground PM increased IL-8 release from PBECs, but this was diminished in mucus-secreting ALI cultures. Fine and ultrafine PM generated a greater level of ROS than coarse PM. ROS generation by ultrafine PM was ameliorated by DFX and NAC, suggesting an iron-dependent mechanism. Despite the presence of mucus, ALI cultures displayed increased HO-1 expression. Intracellular PM was observed within vesicles, mitochondria, and free in the cytosol. The results indicate that, although the mucous layer appears to confer some protection against underground PM, ALI PBECs nonetheless detect PM and mount an antioxidant response. The combination of increased ROS-generating ability of the metal-rich ultrafine fraction and ability of PM to penetrate the mucous layer merits further research. [ABSTRACT FROM AUTHOR]

The article presents the reply to Lipworth for the biology of asthma attacks being more complex than blood eosinophils alone and corticosteroids having a wide range of potentially relevant antiinflammatory effects.

The article highlights the ventilator sharing protocol for COVID-19 disease. Topics include patient compatibility criteria are crucial and require time; patient selection and management require considerable expertise to ensure safety; and lung damage from divergent patient courses does not occur.

Background: Azithromycin is an orally active synthetic macrolide antibiotic with a wide range of anti-bacterial, anti-inflammatory and antiviral properties. It is a safe, inexpensive, generic licenced drug available worldwide and manufactured to scale and is a potential candidate therapy for pandemic coronavirus disease 2019 (COVID-19). Azithromycin was widely used to treat severe SARS-CoV and MERS-CoV, but to date, no randomised data are available in any coronavirus infections. Other ongoing trials are exploring short courses of azithromycin either in early disease, within the first 7 days of symptoms, when azithromycin's antiviral properties may be important, or late in disease when anti-bacterial properties may reduce the risk of secondary bacterial infection. However, the molecule's anti-inflammatory properties, including suppression of pulmonary macrophage-derived pro-inflammatory cytokines such as interleukins-1β, -6, -8, and -18 and cytokines G-CSF and GM-CSF may provide a distinct therapeutic benefit if given in as a prolonged course during the period of progression from moderate to severe disease.Methods: ATOMIC2 is a phase II/III, multi-centre, prospective, open-label, two-arm randomised superiority clinical trial of azithromycin versus standard care for adults presenting to hospital with COVID-19 symptoms who are not admitted at initial presentation. We will enrol adults, ≥ 18 years of age assessed in acute hospitals in the UK with clinical diagnosis of COVID-19 infection where management on an ambulatory care pathway is deemed appropriate. Participants will be randomised in a 1:1 ratio to usual care or to azithromycin 500 mg orally daily for 14 days with telephone follow-up at days 14 and 28. The primary objective is to compare the proportion with either death or respiratory failure requiring invasive or non-invasive mechanical ventilation over 28 days from randomisation. Secondary objectives include mortality/respiratory failure in those with a PCR-confirmed diagnosis; all-cause mortality; progression to pneumonia; progression to severe pneumonia; peak severity of illness and mechanistic analysis of blood and nasal biomarkers.Discussion: This trial will determine the clinical utility of azithromycin in patients with moderately severe, clinically diagnosed COVID-19 and could be rapidly applicable worldwide.Trial Registration: ClinicalTrials.gov NCT04381962 . Registered on 11 May 2020. EudraCT identifier 2020-001740-26 . Opened for accrual on 29 May 2020. [ABSTRACT FROM AUTHOR]

Mucosal associated invariant T (MAIT) cells are evolutionarily-conserved, innate-like lymphocytes which are abundant in human lungs and can contribute to protection against pulmonary bacterial infection. MAIT cells are also activated during human viral infections, yet it remains unknown whether MAIT cells play a significant protective or even detrimental role during viral infections in vivo. Using murine experimental challenge with two strains of influenza A virus, we show that MAIT cells accumulate and are activated early in infection, with upregulation of CD25, CD69 and Granzyme B, peaking at 5 days post-infection. Activation is modulated via cytokines independently of MR1. MAIT cell-deficient MR1−/− mice show enhanced weight loss and mortality to severe (H1N1) influenza. This is ameliorated by prior adoptive transfer of pulmonary MAIT cells in both immunocompetent and immunodeficient RAG2−/−γC−/− mice. Thus, MAIT cells contribute to protection during respiratory viral infections, and constitute a potential target for therapeutic manipulation. MAIT cells are abundant in the lungs and confer protection against bacterial pathogens. Whilst activation of these cells has been described during viral infections, here van Wilgenburg and colleagues show that in a murine model MAIT cells contribute to the protective host immune response to influenza virus infection. [ABSTRACT FROM AUTHOR]