Different eosinophil subpopulations have been identified in asthma and other eosinophilic disorders. However, there is a paucity of data on eosinophil subpopulations in patients with chronic obstructive pulmonary disease (COPD). The aim of this study was to compare eosinophil phenotypes in blood and induced sputum in patients with COPD, asthma and controls. Stable patients with mild-to-moderate COPD (n = 15) and asthma (n = 14) with documented blood eosinophilia ≥100 cells/µL in the year prior to the study and the control group (n = 11) were included to the study. The blood and sputum eosinophil phenotypes were analyzed by flow cytometry. IL-5, IL-13, CCL5 and eotaxin-3 levels were measured in the induced sputum. The marker expression on blood eosinophils was similar among control, asthma and COPD groups. The expressions of CD125, CD193, CD14 and CD62L were higher on blood than on sputum eosinophils in all three groups. We found increased levels of CD193+ and CD66b+ sputum eosinophils from COPD patients, and an elevated level of CD11b+ sputum eosinophils in asthma compared to COPD patients. The results of our study suggest that the profile of marker expression on COPD sputum eosinophils differed from other groups, suggesting a distinct phenotype of eosinophils of COPD patients than in asthma or healthy subjects.

The focus of this study was to determine which chemokine receptors are present on oral fibroblasts and whether these receptors influence proliferation, migration, and/or the release of wound healing mediators. This information may provide insight into the superior wound healing characteristics of the oral mucosa. The gingiva fibroblasts expressed 12 different chemokine receptors (CCR3, CCR4, CCR6, CCR9, CCR10, CXCR1, CXCR2, CXCR4, CXCR5, CXCR7, CX3CR1, and XCR1), as analyzed by flow cytometry. Fourteen corresponding chemokines (CCL5, CCL15, CCL20, CCL22, CCL25, CCL27, CCL28, CXCL1, CXCL8, CXCL11, CXCL12, CXCL13, CX3CL1, and XCL1) were used to study the activation of these receptors on gingiva fibroblasts. Twelve of these fourteen chemokines stimulated gingiva fibroblast migration (all except for CXCL8 and CXCL12). Five of the chemokines stimulated proliferation (CCL5/CCR3, CCL15/CCR3, CCL22/CCR4, CCL28/CCR3/CCR10, and XCL1/XCR1). Furthermore, CCL28/CCR3/CCR10 and CCL22/CCR4 stimulation increased IL-6 secretion and CCL28/CCR3/CCR10 together with CCL27/CCR10 upregulated HGF secretion. Moreover, TIMP-1 secretion was reduced by CCL15/CCR3. In conclusion, this in-vitro study identifies chemokine receptor-ligand pairs which may be used in future targeted wound healing strategies. In particular, we identified the chemokine receptors CCR3 and CCR4, and the mucosa specific chemokine CCL28, as having an predominant role in oral wound healing by increasing human gingiva fibroblast proliferation, migration, and the secretion of IL-6 and HGF and reducing the secretion of TIMP-1.
© 2017 The Authors. Journal of Cellular Physiology Published by wiley periodicals, Inc.

Protease-Activated Receptor-2 (PAR-2), a G protein coupled receptor activated by serine proteases, is widely expressed in humans and is involved in inflammation. PAR-2 activation in the airways plays an important role in the development of allergic airway inflammation. PAR-2 expression is known to be upregulated in the epithelium of asthmatic subjects, but its expression on immune and inflammatory cells in patients with asthma has not been studied.
We recruited 12 severe and 24 mild/moderate asthmatics from the University of Alberta Hospital Asthma Clinics and collected baseline demographic information, medication use and parameters of asthma severity. PAR-2 expression on blood inflammatory cells was analyzed by flow cytometry.
Subjects with severe asthma had higher PAR-2 expression on CD14++CD16+ monocytes (intermediate monocytes) and also higher percentage of CD14++CD16+PAR-2+ monocytes (intermediate monocytes expressing PAR-2) in blood compared to subjects with mild/moderate asthma. Receiver operating characteristics (ROC) curve analysis showed that the percent of CD14++CD16+PAR-2+ in peripheral blood was able to discriminate between patients with severe and those with mild/moderate asthma with high sensitivity and specificity. In addition, among the whole populations, subjects with a history of asthma exacerbations over the last year had higher percent of CD14++CD16+ PAR-2+ cells in peripheral blood compared to subjects without exacerbations.
PAR-2 expression is increased on CD14++CD16+ monocytes in the peripheral blood of subjects with severe asthma and may be a biomarker of asthma severity. Our data suggest that PAR-2 -mediated activation of CD14++CD16+ monocytes may play a role in the pathogenesis of severe asthma.

Aspirin-exacerbated respiratory disease (AERD) is distinguished from aspirin-tolerant asthma/chronic sinusitis in large part by an exuberant infiltration of eosinophils that are characterized by their overexpression of metabolic pathways that drive the constitutive and aspirin-induced secretion of cysteinyl leukotrienes (CysLTs).
We defined the inflammatory milieu that in part drives CysLT overproduction and, in particular, the role of IFN-γ in the differentiation of eosinophils.
Quantitative real-time PCR was performed for TH1 and TH2 signature cytokines on tissue from control subjects, patients with chronic hyperplastic eosinophilic sinusitis, and patients with AERD, and their cellular source was determined. The influence of IFN-γ on maturation, differentiation, and functionality of eosinophils derived from hematopoietic stem cells was determined.
Gene expression analysis revealed that tissue from both aspirin-tolerant subjects and patients with AERD display a TH2 cytokine signature; however, AERD was distinguished from chronic hyperplastic eosinophilic sinusitis by the prominent expression of IFN-γ. Intracellular and immunohistochemical cytokine staining revealed that the major sources of these cytokines were the eosinophils themselves. IFN-γ promoted the maturation of eosinophil progenitors, as measured by increased mRNA and surface expression of CCR3 and sialic acid-binding immunoglobulin-like lectin 8 (Siglec-8). Additionally, IFN-γ increased the expression of genes involved in leukotriene synthesis that led to increased secretion of CysLTs. IFN-γ-matured eosinophil progenitors were also primed, as demonstrated by their enhanced degranulation.
High IFN-γ levels distinguish AERD from aspirin-tolerant asthma and underlie the robust constitutive and aspirin-induced secretion of CysLTs that characterize this disorder.
Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Chemokines and their receptors are involved in the recruitment of leukocytes to sites of inflammation. Recently, chemokine expression signatures have been reported to convey a prognostic value in myelodysplastic syndrome (MDS) patients. In the present study, we investigated the chemokine receptor repertoire on fresh peripheral blood lymphocytes from 31 (22 low-risk and 9 high-risk) patients affected by MDS. Chemokine receptor expression was studied in defined T-cell subsets using eight-color flow cytometry. MDS patients exhibited quantitative differences in peripheral lymphocyte subpopulations. In addition, T cells obtained from MDS patients expressed a chemokine receptor pattern suggesting a dominance of mature and activated T cells. This is illustrated by increased levels of CCR3, CCR5, CX3CR1 and/or by a decreased abundance of CCR7 in defined T-cell subsets. The T-cell subset distribution appears to differ between the peripheral blood and the bone marrow of MDS patients, suggesting a preferential recruitment of specific T-cell subsets to the latter compartment. Alteration in chemokine receptor expression can develop over time even in patients that are considered clinically stable. Elevated expression levels of CXCR4 by CD8+ cells were associated with prolonged patient survival and reduced numbers of bone marrow blasts. We conclude that immunological abnormalities in MDS also involve chemokine receptors on different subsets of T cells, and that these changes may have a prognostic value.