Interleukin 16 and CCL17/thymus and activation-regulated chemokine in patients with aspirin-exacerbated respiratory disease

Transcriptome Analysis Identifies Doublesex and Mab-3 Related Transcription Factor (DMRT3) in Nasal Polyp Epithelial Cells of Patients Suffering from Non-Steroidal Anti-Inflammatory Drug-Exacerbated Respiratory Disease (AERD)

Background: Aspirin-exacerbated respiratory disease (AERD) is a syndrome characterised by chronic rhinosinusitis, nasal polyps, asthma and aspirin intolerance. An imbalance of eicosanoid metabolism with anover-production of cysteinyl leukotrienes (CysLTs) has been associated with AERD. However, the precise mechanisms underlying AERD are unknown. Objective: To establish the transcriptome of the nasal polyp airway epithelial cells derived from AERD patients to discover gene expression patterns in this disease. Methods: Nasal airway epithelial cells were isolated from 12 AERD polyps and 8 AERD non-polyp nasal mucosa samples as controls from the same subjects. Utilising the Illumina HiSeq 2500 platform, RNA samples were sequenced. Potential gene candidate DMRT3 was selected from the differentially-expressed genes for validation. Results: Comparative transcriptome profiling of nasal epithelial cells was accomplished in AERD. A total of 20 genes had twofold mean regulation expression differences or greater. In addition, 8 genes were upregulated, including doublesex and mab-3 related transcription factor 3 (DMRT3), and 12 genes were downregulated. Differentially regulated genes comprised roles in inflammation, defence and immunity. Metabolic process and embryonic development pathways were significantly enriched. Enzyme-linked immune sorbent assay (ELISA) results of DMRT3 in AERD patients were significantly upregulated compared to controls (p = 0.03). Immunohistochemistry (IHC) of AERD nasal polyps localised DMRT3 and was predominantly released in the airway epithelia. Conclusion: Findings suggest that DMRT3 could be potentially involved in nasal polyp development in AERD patients. Furthermore, several genes are downregulated, hinting at the dedifferentiation phenomenon in AERD polyps. However, further studies are imperative to confirm the exact mechanism of polyp formation in AERD patients.

Cellular interactions in aspirin-exacerbated respiratory disease

PURPOSE OF REVIEW

The purpose of this review is to summarize the complex cellular interactions of aspirin-exacerbated respiratory disease (AERD) and how these interactions promote pathogenic mechanisms of AERD.

RECENT FINDINGS

In addition to characteristic changes in eicosanoid levels, recent studies have identified increases in alarmin cytokines (IL-33, thymic stromal lymphopoietin) as well as activated innate lymphoid and plasma cell populations in samples from AERD patients.

SUMMARY

Patients with AERD typically demonstrate high levels of proinflammatory eicosanoids including cysteinyl leukotrienes (CysLTs) and prostaglandin D2 (PGD2) and hyporesponsiveness to prostaglandin E2 (PGE2). CysLTs are released by mast cells, eosinophils, and adherent platelets and promote epithelial release of IL-33, which activates mast cells and group 2 innate lymphoid cells (ILC2s) in concert with CysLTs. TSLP induces PGD2 release from mast cells which activates and recruits eosinophils, basophils, Th2 cells, and ILC2s via CRTH2. In turn, ILC2s and other cell types produce Th2 cytokines IL-4, IL-5, and IL-13 that, along with CysLTs and PGD2, promote bronchoconstriction, eosinophilic tissue inflammation, and mucus production.

Diagnostic value of thymus and activation-regulated chemokine and of periostin in eosinophilic asthma: A prospective study

Background: Serum thymus and activation-regulated chemokine (TARC) and periostin are reliable biomarkers in eosinophilic asthma. Objective: This study was carried out to determine the use of periostin and TARC as biomarkers in asthma and to compare the superiority of one over the other, especially in asthma with an eosinophilic phenotype. Methods: The study was conducted with 87 patients with asthma and 42 healthy control subjects. Patients with asthma were also divided into eosinophilic and non-eosinophilic phenotypes. A pulmonary function test was performed in all the participants, and serum and induced sputum TARC, periostin concentrations, eosinophils, and total immunoglobulin E values were examined. Results: TARC and periostin levels were significantly higher in the asthma group than in the control group (p < 0.001). The serum TARC level in the eosinophilic group was significantly higher than in the non-eosinophilic and control groups (p < 0.001). The induced sputum TARC level was significantly higher in the non-eosinophilic group than in the control group (p < 0.001). The TARC and periostin levels of the patients were evaluated by using receiver operator characteristic analysis. The cutoff value for TARC was determined to be 1415.39 ng/L; likewise, the cutoff value for periostin was 107.60 ng/L. The present study detected that serum levels of TARC correlated to serum levels of periostin (r = 0.54; p = 0.032). Furthermore, when evaluating correlations between serum and sputum levels, there was a correlation detected between TARC and periostin in serum, whereas this correlation was stronger in sputum: r = 0.66, p = 0.020; and r = 0.62, p = 0.028, respectively. Conclusion: Serum and sputum TARC and periostin may contribute for monitoring the improvement of patients, particularly those with asthma. Furthermore, TARC was a more reliable biomarker than periostin for patients with eosinophilic asthma.

The behavioral, cellular and immune mediators of HIV-1 acquisition: New insights from population genetics

Millions are exposed to the human immunodeficiency virus type 1 (HIV-1) every year, but not all acquire the virus, suggesting a potential role for host genetics in the moderation of HIV-1 acquisition. Here, we analyzed summary statistics from the largest genome-wide association study of HIV-1 acquisition to-date, consisting of 6,334 infected patients and 7,247 population controls, to advance our understanding of the genetic mechanisms implicated in this trait. We found that HIV-1 acquisition is polygenic and heritable, with SNP heritability estimates explaining 28-42% of the variance in this trait at a population level. Genetic correlations alongside UK Biobank data revealed associations with smoking, prospective memory and socioeconomic traits. Gene-level enrichment analysis identified EF-hand calcium binding domain 14 as a novel susceptibility gene for HIV-1 acquisition. We also observed that susceptibility variants for HIV-1 acquisition were significantly enriched for genes expressed in T-cells, but also in striatal and hippocampal neurons. Finally, we tested how polygenic risk scores for HIV-1 acquisition influence blood levels of 35 inflammatory markers in 406 HIV-1-negative individuals. We found that higher genetic risk for HIV-1 acquisition was associated with lower levels of C-C motif chemokine ligand 17. Our findings corroborate a complex model for HIV-1 acquisition, whereby susceptibility is partly heritable and moderated by specific behavioral, cellular and immunological parameters.

Heterogeneity of NSAID-Exacerbated Respiratory Disease: has the time come for subphenotyping?

PURPOSE OF REVIEW

NSAID-Exacerbated Disease (N-ERD) is a chronic eosinophilic inflammatory disorder of the respiratory tract occurring in patients with asthma and/or rhinosinusitis with nasal polyps, whose symptoms are exacerbated by NSAIDs. The purpose of this review is to provide an update on clinical characteristics, pathophysiology, and management of N-ERD, and to emphasize heterogeneity of this syndrome.

RECENT FINDINGS

Growing evidence indicates that N-ERD, which has been considered a separate asthma phenotype, is heterogenous, and can be divided in several subphenotypes varying in clinical characteristics. Pathophysiology of N-ERD is complex and extends beyond abnormalities in the arachidonic acid metabolism. Heterogeneity of pathophysiological mechanisms underlying development of airway inflammation seems to be associated with variability in response to both anti-inflammatory and disease-specific treatments (e.g., with aspirin after desensitization).

SUMMARY

Progress in understanding of the pathophysiology of N-ERD leads to discovery and validation of new biomarkers facilitating diagnosis and predicting the response to treatment of the chronic inflammation underlying upper (CRSwNP) and lower airway (asthma) symptoms. Better characterization of the immunophysiopathological heterogeneity of N-ERD (identification of endotypes) may allow more personalized, endotype-driven approach to treatment in the future.

Aspirin exacerbated respiratory disease: Current topics and trends

Aspirin-exacerbated respiratory disease is a chronic and treatment-resistant disease, characterized by the presence of eosinophilic rhinosinusitis, nasal polyposis, bronchial asthma, and nonsteroidal anti-inflammatory drugs hypersensitivity. Alterations in arachidonic acid metabolism may induce an imbalance between pro-inflammatory and anti-inflammatory substances, expressed as an overproduction of cysteinyl leukotrienes and an underproduction of prostaglandin E2. Although eosinophils play a key role, recent studies have shown the importance of other cells and molecules in the development of the disease like mast cells, basophils, lymphocytes, platelets, neutrophils, macrophages, epithelial respiratory cells, IL-33 and thymic stromal lymphopoietin, making each of them promissory diagnostic and treatment targets. In this review, we summarize the most important clinical aspects of the disease, including the current topics about diagnosis and treatment, like provocation challenges and aspirin desensitization. We also discuss recent findings in the pathogenesis of the disease, as well as future trends in diagnosis and treatment, including monoclonal antibodies and a low salicylate diet as a treatment option.

Elevated plasma levels of interleukin-16 in patients with acute myocardial infarction

Interleukin (IL)-16, a polypeptide cytokine, plays a crucial role in the inflammatory process, acting as a chemoattractant for peripheral immune cells and has been linked to various inflammatory diseases. However, its role in patients with acute myocardial infarction (AMI) is unclear.We retrospectively analyzed serum levels of IL-16 in blood of patients with (STEMI, n = 45) and without ST-segment elevation myocardial infarction (NSTEMI, n = 42) compared with controls with excluded coronary artery disease (n = 55). Furthermore, correlation analysis with inflammatory cells, C-reactive protein (CRP) levels, dendritic cell precursors (DCPs), and other clinical and biochemical markers was performed.Compared with controls, patients with STEMI and NSTEMI evidenced higher levels of IL-16 in pg/mL (STEMI: 759.38 ± 471.54, NSTEMI: 677.77 ± 438.8, control: 500.45 ± 432.21; P = .002). IL-16 correlated with CRP (r = 0.26, P = .001), leucocytes (r = 0.38, P < .001), NT-proBNP (r = 0.20, P = .02) and hsTnT (r = 0.25, P = .004). Circulating myeloid DCPs, plasmacytoid DCPs, and total DCPs showed a significant inverse correlation to IL-16 levels (r = -0.21, P = .01; r = -0.23, P = .005; r = -0.26, P = .002, respectively).Interleukin-16 might play an important role in the inflammatory process of patients suffering from AMI and correlates with inflammatory cell activation and clinical and biochemical markers. The cytokine IL-16 might upregulate the proinflammatory response and recruitment of inflammatory cells into infarcted myocardium.