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Chronic obstructive pulmonary disease (COPD) is an inflammatory airways disease with limited therapeutic options. We have previously shown that mesenchymal stromal cell (MSC) infusions are well tolerated in patients with COPD and reduce circulatory biomarkers associated with systemic inflammation and oxidative stress. This study aimed to delineate the underlying mechanisms further by characterizing the transcriptional networks in these patients and to explore the role of MSC‐derived paracrine factors in regulating these pathways. Allogeneic, bone marrow‐derived MSCs were systemically administered into patients with stable COPD (n = 9). Gene expression profiles from peripheral blood mononuclear cells (PBMCs) were analyzed across the first week after infusion. Paracrine mechanisms associated with these transcriptional changes were explored further by culturing patient PBMCs with MSC‐conditioned medium (MSC‐CM) or post‐MSC infusion (PI) plasma to measure the regulatory effects of soluble factors that may be derived from MSCs. MSC‐CM and PI‐plasma were characterized further to identify potential immunoregulatory candidates. MSC infusion elicited a strong but transient transcriptional response in patient PBMCs that was sustained up to 7 days. MSC infusion strongly downregulated transcriptional pathways related to interleukin (IL)‐8 and IL‐1β, which were also significantly inhibited in vitro following co‐culture of PBMCs with MSC‐CM and PI‐plasma. MSC‐derived soluble tumor necrosis factor receptor‐1, transforming growth factor‐β1, and extracellular vesicle‐associated microRNAs were identified as potential mechanisms promoting these changes, but depletion of these individual candidates revealed inconsistent results. MSC‐derived paracrine factors modulate important inflammatory pathways that are relevant to COPD pathogenesis. These data strengthen the hypothesis that therapies using MSCs and their secreted products may be beneficial to patients with COPD., Mesenchymal stromal cells (MSC) are potent immunomodulators that have shown promise in treating chronic obstructive pulmonary disease (COPD). Using transcriptomics, we have demonstrated that MSC infusions elicit a strong, yet transient (

Peripheral blood is a valuable, non-invasive source of biomarkers which include circulating miRNAs. Using microfluidic array-based techniques, miRNAs can be successfully measured in small amounts of blood plasma (< 0.5 mL) using cDNA pre-amplification. However, the use of heparin-based anticoagulants for blood collection hinders the detection of circulating miRNAs due to its inhibitory effect on PCR components. Although pre-treatment with heparinase have been shown to overcome heparin contamination in blood, its effect has not been described in array-based analyses or more sensitive applications with smaller sample volumes (i.e. 200 μL plasma) requiring pre-amplification. We show that the treatment of miRNA extracted from heparinised plasma with an optimised concentration of Bacteroides heparinase I prior to cDNA pre-amplification dramatically improves the number of detectable miRNA from 2 to 67 targets on the TaqMan® Array Human MicroRNA Cards. Furthermore, the titrated amount of heparinase (3 U) gave the best miRNA detection compared to those used in previous studies (6-24 U). This study provides novel data which demonstrates that heparinase treatment is compatible with protocols that involve pre-amplification of cDNA and microfluidic array-based techniques. This an improved methodology that permits miRNA-based biomarker analysis from small volume of heparinised plasma.

Chronic obstructive pulmonary disease (COPD) is characterised by a progressive pulmonary and systemic inflammation. Acute exacerbations of COPD (AECOPD) are associated with acute inflammation and infection, increase in the rates of morbidity and mortality. Previous proteomic studies have focussed on identifying proteins involved in COPD pathogenesis in samples collected from the lung (e.g. lung tissue biopsies, bronchoalveolar lavage and sputum) but not from blood of patients who experienced AECOPD. In this study, plasma was analysed by two independent quantitative proteomics techniques; isobaric tag for relative and absolute quantitation (iTRAQ) and multiple reaction monitoring (MRM) to identify differential expression of circulating proteins in patients with stable COPD (sCOPD) and AECOPD. Firstly, iTRAQ performed on pooled plasma samples from AECOPD, sCOPD, and healthy non-smoking controls (HC) revealed 15 differentially expressed proteins between the 3 groups. MRM subsequently performed on a separate cohort of AECOPD, sCOPD, and HC patients confirmed 9 proteins to be differentially expressed by AECOPD compared to HC (Afamin, alpha-1-antichymotrypsin, Apolipoprotein E, Beta-2-glycoprotein 1, Complement component C9, Fibronectin, Immunoglobulin lambda like polypeptide 5, Inter-alpha-trypsin inhibitor heavy chain H3, Leucine rich alpha-2-glycoprotein 1). Network analysis demonstrates that most of these proteins are involved in proteolysis regulation, platelet degranulation and cholesterol metabolism. In conclusion, several potential plasma biomarkers for AECOPD were identified in this study. Further validation studies of these proteins may elucidate their roles in the development of AECOPD.

BackgroundIdiopathic pulmonary fibrosis (IPF) is a progressive lung disease in which circulatory biomarkers have the potential for guiding management in clinical practice. We assessed the prognostic role of serum biomarkers in three independent IPF cohorts: Australian Idiopathic Pulmonary Fibrosis Registry (AIPFR), Trent Lung Fibrosis (TLF) and Prospective Observation of Fibrosis in the Lung Clinical Endpoints (PROFILE).MethodsIn the AIPFR cohort, candidate proteins were assessed by ELISA as well as in an unbiased proteomic approach. LASSO (least absolute shrinkage and selection operator) regression was used to restrict the selection of markers that best accounted for the progressor phenotype at 1 year in the AIPFR cohort, and subsequently prospectively selected for replication in the validation TLF cohort and assessed retrospectively in the PROFILE cohort. Four significantly replicating biomarkers were aggregated into a progression index model based on tertiles of circulating concentrations.Results189 participants were included in the AIPFR cohort, 205 participants from the TLF cohort and 122 participants from the PROFILE cohort. Differential biomarker expression was observed by ELISA and replicated for osteopontin, matrix metallopeptidase-7, intercellular adhesion molecule-1 and periostin for those with a progressor phenotype at 1 year. Proteomic data did not replicate. The progression index in the AIPFR, TLF and PROFILE cohorts predicted risk of progression, mortality and progression-free survival. A statistical model incorporating the progression index demonstrated the capacity to distinguish disease progression at 12 months, which was increased beyond the clinical GAP (gender, age and physiology) score model alone in all cohorts, and significantly so within the incidence-based TLF and PROFILE cohorts.ConclusionA panel of circulatory biomarkers can provide potentially valuable clinical assistance in the prognosis of IPF patients.

Chronic obstructive pulmonary disease (COPD) is characterized by progressive pulmonary and systemic inflammation. Acute exacerbations of COPD (AECOPD) are associated with acute inflammation and infections and increase the rates of morbidity and mortality. Currently, neither the aetiology nor pathogenesis of AECOPD are entirely understood. Exosomes have been reported to regulate immunity and inflammation via specific intercellular communications through an array of macromolecules (e.g. microRNA and proteins) contained within these microvesicles. We evaluated the level of circulating exosomes in relation to systemic inflammation in patients with AECOPD (n = 20) or stable COPD (sCOPD; n = 20) in comparison to non-smoking healthy controls (n = 20). Exosomes in plasma were isolated by precipitation-based method, and quantified using a CD9 expression based enzyme-linked immunosorbent assay (ELISA). Plasma biomarkers of systemic inflammation, C-reactive protein (CRP), soluble tumour necrosis factor receptor-1 (sTNFR1) and interleukin (IL)-6 were also quantified using ELISA. Levels of plasma exosome were higher in AECOPD patients (p < 0.001) and sCOPD patients (p < 0.05) compared to controls. Plasma levels of CRP and sTNFR1 were highest in AECOPD, followed by sCOPD patients compared to healthy controls (p < 0.05). Plasma IL-6 was elevated in AECOPD (p < 0.05) and sCOPD patients (p < 0.01) compared to controls. The level of exosome correlated with the levels of CRP, sTNFR1 and IL-6 in plasma. Exosomes may therefore be involved in the inflammatory process of AECOPD. Further studies involving exosomal phenotyping and molecular characterization are required to fully understand their role in the pathophysiology of COPD.

Impaired T helper type 1 (Th1) function is implicated in the susceptibility of patients with chronic obstructive pulmonary disease (COPD) to respiratory infections, which are common causes of acute exacerbations of COPD (AECOPD). To understand the underlying mechanisms, we assessed regulatory T (Treg) cells and the expression of an inhibitory T-cell receptor, cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4). Cryopreserved peripheral blood mononuclear cells (PBMC) from patients with AECOPD (n = 17), patients with stable COPD (sCOPD; n = 24) and age-matched healthy non-smoking controls (n = 26) were cultured for 24 hr with brefeldin-A or monensin to detect intracellular or surface CTLA-4 (respectively) by flow cytometry. T cells in PBMC from AECOPD (n = 9), sCOPD (n = 14) and controls (n = 12) were stimulated with anti-CD3 with and without anti-CTLA-4 blocking antibodies and cytokines were quantified by ELISA. Frequencies of circulating T cells expressing intracellular CTLA-4 were higher in sCOPD (P = 0·01), whereas patients with AECOPD had more T cells expressing surface CTLA-4 than healthy controls (P = 0·03). Increased frequencies of surface CTLA-4+ CD4+ T cells and CTLA-4+ Treg cells paralleled increases in plasma soluble tumour necrosis factor receptor-1 levels (r = 0·32, P = 0·01 and r = 0·29, P = 0·02, respectively) in all subjects. Interferon-γ responses to anti-CD3 stimulation were inversely proportional to frequencies of CD4+ T cells expressing intracellular CTLA-4 (r = -0·43, P = 0·01). Moreover, CTLA-4 blockade increased the induction of interferon-γ, tumour necrosis factor-α and interleukin-6 in PBMC stimulated with anti-CD3. Overall, chronic inflammation may expand sub-populations of T cells expressing CTLA-4 in COPD patients and therefore impair T-cell function. CTLA-4 blockade may restore Th1 function in patients with COPD and so aid the clearance of bacterial pathogens responsible for AECOPD.

Poor T-cell function is implicated in susceptibility to infections in COPD patients. Proportion of circulating PD-1+ CD4+ T-cells is elevated in AECOPD patients. Systemic inflammation is associated with elevated proportion of PD-1+ CD4+ T-cells. PD-1 blockade increased the production of IFNγ, TNF, IL-6 and IL-10 by anti-CD3-induced PBMC.

Idiopathic pulmonary fibrosis (IPF) is a chronic disease characterised by progressive decline in pulmonary function. The rate of decline can vary, with some patients remaining stable over longer periods of time and others rapidly progressing [1]. tThe variable progression of this disease makes it difficult to elucidate pathogenic pathways involved in the initiation and progression of IPF. Advances in high-throughput gene-expression analyses have led to improvements in our understanding of disease biology and prognostic gene signatures. We hypothesise that IPF has a unique circulatory transcriptional profile compared to healthy controls, with additional differences between stable and progressive disease likely related to disease pathogenesis. Footnotes This manuscript has recently been accepted for publication in the European Respiratory Journal . It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJ online. Please open or download the PDF to view this article. Conflict of interest: Miss Clynick has nothing to disclose. Conflict of interest: Dr. Jo has nothing to disclose. Conflict of interest: Dr. Corte has nothing to disclose. Conflict of interest: Dr. Glaspole has nothing to disclose. Conflict of interest: Dr. Grainge has nothing to disclose. Conflict of interest: Dr. Hopkins has nothing to disclose. Conflict of interest: Dr. Reynolds has nothing to disclose. Conflict of interest: Dr. Chapman has nothing to disclose. Conflict of interest: Dr. Walters has nothing to disclose. Conflict of interest: Dr. Zappala has nothing to disclose. Conflict of interest: Dr. Keir has nothing to disclose. Conflict of interest: Dr. Cooper has nothing to disclose. Conflict of interest: Dr. Mahar has nothing to disclose. Conflict of interest: Dr. Ellis has nothing to disclose. Conflict of interest: Dr. Goh has nothing to disclose. Conflict of interest: Dr. Baltic has nothing to disclose. Conflict of interest: Miss Ryan has nothing to disclose. Conflict of interest: Dr. Tan has nothing to disclose. Conflict of interest: Dr. Moodley has nothing to disclose.

We have previously demonstrated that HIV-1 p24-specific plasmacytoid dendritic cell-reactive opsonophagocytic antibody (PROAb) responses associate with control of chronic HIV infection. Here, we examined whether HIV-1 p24-specific PROAbs associate with control of early HIV infection and their relationship with HIV-1 p24-specific IgG subclasses.Plasma collected at 8 and 52 weeks following primary HIV-1 infection was obtained from antiretroviral therapy-naïve patients who were classified as 'good' (plasma HIV-1 RNA 5000 copies/ml; n = 17) or 'poor' (HIV-1 RNA 50 000 copies/ml; n = 15) controllers at week 52. HIV-1 p24-specific PROAb responses were assayed using a plasmacytoid dendritic cell line (Gen2.2), and HIV-1 p24-specific IgG3, IgG1 and IgG2 levels were assayed by ELISA.HIV-1 p24-specific PROAb responses increased in 'good controllers' (P = 0.01) but remained unchanged in 'poor controllers' between weeks 8 and 52. Of the HIV-1 p24-specific IgG subclasses measured, only IgG1 increased over this time period in 'good controllers' alone (P = 0.003), which correlated with the increase in HIV-1 p24-specific PROAb responses (r = 0.83, P 0.0001). Depletion of IgG1 from IgG preparations of 'good controllers' resulted in the inhibition of HIV-1 p24-specific PROAb responses. In the total patient cohort, plasma HIV-1 RNA levels at week 52 correlated inversely with changes in HIV-1 p24-specific PROAb responses (r = -0.37, P = 0.04) and IgG1 (r = -0.51, P = 0.003) levels between weeks 8 and 52.Control of early HIV-1 infection was associated with an increase in HIV-1 p24-specific PROAb responses, which was mediated by HIV-1 p24-specific IgG1 antibodies. These findings provide further evidence that antibodies to HIV core proteins may contribute to control of HIV-1 infection.

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are characterized by increased pulmonary and systemic inflammation and commonly caused by bacterial and/or viral infection. Little is known about the T-cell dysregulation in AECOPD that promotes these outcomes. CD39 is an ectonucleotidase able to hydrolyse adenosine triphosphate to create adenosine that may inhibit T-cell responses in patients with AECOPD. Here T-cell expression of CD39 measured by flow cytometry was higher in AECOPD patients than stable COPD patients or healthy controls. Higher expression of CD39 was associated with higher levels of plasma soluble tumor necrosis factor receptor but lower interferon-γ (IFNγ) levels in supernatants from staphylococcal enterotoxin-B stimulated peripheral blood mononuclear cells. This links increased expression of CD39 with systemic inflammation and impaired T-cell responses (e.g. IFNγ). The blockade of CD39 pathways may be a novel approach to the control of AECOPD, reducing the dependency on antibiotics.

Identifying the mechanisms of natural control of HIV-1 infection could lead to novel approaches to prevent or cure HIV infection. Several studies have associated natural control of HIV-1 infection with IgG antibodies against HIV-1 Gag proteins (e.g. p24) and/or production of IgG2 antibodies against HIV-1 proteins. These antibodies likely exert their effect by activating anti-viral effector cell responses rather than virus neutralization. We hypothesized that an opsonophagocytic IgG antibody response against HIV-1 p24 that activates plasmacytoid dendritic cells (pDCs) through FcγRIIa would be associated with control of HIV and that this would be enhanced by antibody isotype diversification. Using the Gen2.2 pDC cell line, we demonstrated that pDC-reactive opsonophagocytic IgG antibody responses against HIV-1 p24 were higher in HIV controllers (HIV RNA 10,000 copies/mL) particularly in controllers with low but detectable viremia (HIV RNA 75–2000 copies/mL). Opsonophagocytic antibody responses correlated with plasma levels of IgG1 and IgG2 anti-HIV-1 p24 and notably, correlated inversely with plasma HIV RNA levels in viremic HIV patients. Phagocytosis of these antibodies was mediated via FcγRIIa. Isotype diversification (towards IgG2) was greatest in HIV controllers and depletion of IgG2 from immunoglobulin preparations indicated that IgG2 antibodies to HIV-1 p24 do not enhance phagocytosis, suggesting that they enhance other aspects of antibody function, such as antigen opsonization. Our findings emulate those for pDC-reactive opsonophagocytic antibody responses against coxsackie, picorna and influenza viruses and demonstrate a previously undefined immune correlate of HIV-1 control that may be relevant to HIV vaccine development.

To expand upon our previous observation that HIV-1 Gag-specific IgG antibodies were highest in HIV controllers not carrying HLA-B*57:01, we analysed these antibodies in a larger cohort of viremic controllers (VCs) or elite controllers (ECs) considering carriage of ‘protective’ HLA-B alleles. HIV-1 p24-specific IgG1 and IgG2 antibodies were higher only in HLA-B*57:01− VCs but there were no differences in ECs. Associations of HIV-1 gp140-specific IgG antibodies with HLA-B*57:01 carriage were inconsistent amongst VCs and ECs.

Pulmonary disease due to non-tuberculous mycobacteria (NTM) is caused by several species (particularly Mycobacterium avium, Mycobacterium intracellulare) that are abundant in the environment. Th1 cytokines such as interferon (IFN)-γ are important in the control of mycobacteria, but in vitro production of IFN-γ is not deficient in adult patients with pulmonary NTM disease. Antibodies reactive with IFN-γ have been described in patients with disseminated NTM disease, but it is not clear whether they are common in pulmonary disease. Here we show that patients with pulmonary NTM have a higher level of anti-IFN-γ and anti-GM-CSF antibodies than healthy controls, although some controls also have high levels. Levels of anti-IFN-γ antibodies did not correlate with levels of total immunoglobulin. Longitudinal studies are required to determine whether anti-cytokine autoantibodies are consequence rather than a cause of pulmonary NTM disease.

Objectives: Most HIV patients who experience Mycobacterium tuberculosis-associated immune restoration disease (TB IRD) display elevated interferon-gamma (IFN gamma) responses against mycobacterial antigens, but these can occur without an IRD. Recognition of mycobacteria-associated molecular patterns through toll-like receptors (TLRs) on dendritic cells and monocytes induces cytokine production. Here, we investigate TLR-induced responses in IRD. Design: Peripheral blood mononuclear cells (PBMCs) were collected at approximately weeks 0, 6, 12, 24 and 48 after antiretroviral therapy from five patients experiencing TB IRD, nine matched non-IRD patients and 15 healthy controls. Methods: IFNg production by PBMC stimulated with protein purified derivative (PPD) was assessed by ELISpot. TLR2 expression on myeloid dendritic cells (mDCs) and monocytes was assessed by flowcytometry. TNF alpha, IL-12p40 and IL-10 were measured by ELISA in 24-h cultures of PBMC with lipomannan (mycobacteria-derived TLR2 agonist). Results: TLR2 expression on mDC and monocytes was higher in patients than controls at baseline (P

Mesenchymal stromal cell infusion may provide an alternative immune-based therapeutic option for COPD patients http://ow.ly/5DpA30hQS6y

Chronic obstructive pulmonary disease (COPD) is characterized by chronic irreversible inflammation and progressive decline in lung function. While smoking and other environmental agents (e.g., air pollutants) are common causes of COPD, the major challenges in managing this condition are the persistent inflammation and functional deterioration which are not reversed by removal of precipitating agents (e.g., smoking cessation) or treatment with anti-inflammatory agents. We hypothesized that the reactivation of latent CMV infection may trigger expansion of pro-inflammatory CD28null T cells and hence promote sysmetic inflammation in patients with COPD. This study presents novel data showing increased levels of CMV-reactive IgM and IgG in COPD patients compared to controls. This paralleled observed increases in markers of sytemic inflammation ex vivo and proportions of circulating CD28null T cells. This mechanism may explain the persistent inflammation in COPD patients.

Anti-inflammatory pathways affecting chronic obstructive pulmonary disease (COPD) are poorly understood. Regulatory T-cells (Tregs) are important negative regulators of T-cell activity and hence were investigated in COPD patients in this study. We hypothesised that functional defects in Tregs may promote increased inflammation contributing to the pathogenesis of COPD. Peripheral blood mononuclear cells (PBMC) were isolated from patients with stable COPD and age-matched non-smoking controls. Treg-mediated suppression of memory non-Treg (Foxp3(-)CD45RO(+)) CD4(+) T-cell activation was analysed by comparing PBMC responses to staphylococcal enterotoxin-B (SEB) pre- and post-depletion of Tregs (CD25(+)CD127(low)CD4(+) T-cells) by fluorescence-activated cell sorting (FACS). Activation of T-cells was assessed by HLA-DR expression. Levels of secreted cytokines were measured by ELISA. Depletion of Tregs increased SEB-induced activation of Foxp3(-)CD45RO(+) CD4(+) T-cells in samples from 15/15 healthy controls (demonstrating Treg-mediated suppression) and 9/14 COPD patients (Fisher's test, p=0.017). A screen of clinical data associated a failure of Treg-mediated suppression in the remaining five COPD patients with a higher body mass index (BMI) (33-38 kg/m(2)) compared to patients with unimpaired Treg function (20-32 kg/m(2)). In conclusion, we demonstrate impaired Treg-mediated suppression of CD4(+) T-cell activation in a subset of COPD patients, all of whom had high BMI. Obesity and/or perturbed homeostasis of Treg subsets may explain this defect and therefore contribute to increased inflammation observed in COPD.

Systemic inflammation is a feature of chronic obstructive pulmonary disease (COPD). Defects in T cell-mediated anti-inflammatory pathways such as cytotoxic T lymphocyte antigen-4 (CTLA-4) may promote damaging inflammation. This study provides novel data implicating the impaired induction of an anti-inflammatory molecule, CTLA-4 in the elevated inflammation observed in COPD patients. Low induction of CTLA-4 in COPD patients paralleled increased markers of systemic inflammation ex vivo and increased T-cell responses to a bacterial superantigen, staphylococcal enterotoxin-B (SEB) in vitro. This mechanism may explain the increased inflammation in COPD patients.

Myeloid-derived suppressor cells (MDSC) have been implicated in the regulation of chronic inflammation. Chronic obstructive pulmonary disease (COPD) involves persistent inflammation, but the role of MDSC has not been explored. Here, proportions of MDSC (CD14 − HLA-DR − CD33 + CD11b + cells) were quantified in peripheral blood mononuclear cells (PBMC) isolated from patients with ‘stable’ COPD ( n = 12), smokers with no evidence of COPD ( n = 11) and healthy non-smokers ( n = 11). The proportions of MDSC were similar in all groups. MDSC function was assessed by comparing T-cell and cytokine responses of whole and MDSC-depleted PBMC stimulated with Staphylococcus enterotoxin-B (SEB). Depletion of MDSC did not enhance CD4 + or CD8 + T-cell activation and proliferation, or alter IFNγ and IL-17 production in response to SEB. However production of TGFβ decreased after depletion of MDSC, so MDSC may be a source of this cytokine. In conclusion, COPD was not associated with perturbations in the proportion or function of MDSC in peripheral blood.

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is a major cause of global morbidity and mortality. Mesenchymal stem cells (MSC) have shown promise in treating inflammatory lung conditions. We hypothesised that human MSC (hMSC) can improve ALI/ARDS through their anti-inflammatory actions. We subjected pigs (n = 6) to intravenous oleic acid (OA) injury, ventilation and hMSC infusion, while the controls (n = 5) had intravenous OA, ventilation and an infusion vehicle control. hMSC were infused 1 h after the administration of OA. The animals were monitored for additional 4 h. Nuclear translocation of nuclear factor-light chain enhancer of activated B cells (NF-κB), a transcription factor that mediates several inflammatory pathways was reduced in hMSC treated pigs compared to controls (p = 0.04). There was no significant difference in lung injury, assessed by histological scoring in hMSC treated pigs versus controls (p = 0.063). There was no difference in neutrophil counts between hMSC-treated pigs and controls. Within 4 h, there was no difference in the levels of IL-10 and IL-8 pre- and post-treatment with hMSC. In addition, there was no difference in hemodynamics, lung mechanics or arterial blood gases between hMSC treated animals and controls. Subsequent studies are required to determine if the observed decrease in inflammatory transcription factors will translate into improvement in inflammation and in physiological parameters over the long term.