87 research outputs found
Smoking cessation
Copyright © 2005 Australian Prescriber Reproduced with permission from Australian Prescriber The document attached has been archived with permission from the publisher/copyright holder.Jersmann
The drug efflux pump Pgp1 in pro-inflammatory lymphocytes is a target for novel treatment strategies in COPD
Extent: 8 p.BACKGROUND: Pro-inflammatory/cytotoxic T cells (IFNγ, TNFα, granzyme B+) are increased in the peripheral circulation in COPD. NKT-like and NK cells are effector lymphocytes that we have also shown to be major sources of pro-inflammatory cytokines and granzymes. P-glycoprotein 1 (Pgp1) is a transmembrane efflux pump well characterised in drug resistant cancer cells. We hypothesized that Pgp1 would be increased in peripheral blood T, NKT-like and NK cells in patients with COPD, and that this would be accompanied by increased expression of IFNγ, TNFα and granzyme B. We further hypothesized that treatment with cyclosporine A, a Pgp1 inhibitor, would render cells more sensitive to treatment with corticosteroids. METHODS: Pgp1, granzyme B, IFNγ and TNFα expression were measured in peripheral blood T, NK and NKT-like cells from COPD patients and control subjects (± cyclosporine A and prednisolone) following in vitro stimulation and results correlated with uptake of efflux dye Calcein-AM using flow cytometry. RESULTS: There was increased Pgp1 expression by peripheral blood T, NKT-like and NK cells co-expressing IFNγ, TNFα and granzyme B in COPD patients compared with controls (e.g. %IFNγ/Pgp1 T, NKT-like, NK for COPD (Control): 25(6), 54(27), 39(23)). There was an inverse correlation between Pgp1 expression and Calcein-AM uptake. Treatment with 2.5 ng/ml cylosporin A and10-6 M prednisolone resulted in synergistic inhibition of pro-inflammatory cytokines in Pgp1 + cells (p < 0.05 for all). CONCLUSIONS: Treatment strategies that target Pgp1 in T, NKT-like and NK cells may reduce systemic inflammatory mediators in COPD and improve patient morbidity.Greg Hodge, Mark Holmes, Hubertus Jersmann, Paul N. Reynolds and Sandra Hodg
Targeting peripheral blood pro-inflammatory cytotoxic lymphocytes by inhibiting CD137 expression: novel potential treatment for COPD
Background: We have shown that chronic obstructive pulmonary disease (COPD) is associated with increased production of pro-inflammatory cytokines and the cytotoxic mediator, granzyme B by peripheral blood steroid resistant CD28nullCD137 + CD8+ T cells and granzyme B by NKT-like and NK cells. We hypothesized that we could target these pro-inflammatory/cytotoxic lymphocytes by inhibiting co-stimulation through CD137. Methods: Isolated PBMC from patients with COPD and healthy controls were stimulated with phytohaemagglutinin (PHA) ± blocking anti-CD137 ± 10-6 M methylprednislone (MP) (±stimulatory anti-CD137 ± control antibodies). Pro-inflammatory cytokine profiles and expression of granzyme B, by T, NKT-like CD28 ± subsets and NK cells were determined using flow cytometry. Results: There was a significant decrease in the percentage of T, NKT-like subsets and NK cells producing IFNγ, TNFα and granzyme B in all subjects in the presence of anti-CD137 blocking antibody compared with PHA alone (eg, 60% decrease in CD8 + granzyme B + cells) or MP. Stimulatory anti-CD137 was associated with an increase in the percentage of pro-inflammatory/cytotoxic cells. The inhibitory effect of anti-CD137 on IFNγ, TNFα and granzyme B production by CD28null cells was greater than by CD28+ cells. Conclusions: Blocking CD137 expression is associated with downregulation of IFNγ, TNFα and granzyme B by CD8+ T and NKT-like and NK cells. Targeting CD137 may have novel therapeutic implications for patients with COPD.Greg Hodge, Mark Holmes, Hubertus Jersmann, Paul N Reynolds and Sandra Hodg
Lymphocyte senescence in COPD is associated with loss of glucocorticoid receptor expression by pro-inflammatory/cytotoxic lymphocytes
BACKGROUND Glucocorticoid (GC) resistance is a major barrier in COPD treatment. We have shown increased expression of the drug efflux pump, Pgp1 in cytotoxic/pro-inflammatory lymphocytes in COPD. Loss of lymphocyte co-stimulatory molecule CD28 (lymphocyte senescence) was associated with a further increase in their pro-inflammatory/cytotoxic potential and resistance to GC. We hypothesized that lymphocyte senescence and increased Pgp1 are also associated with down-regulation of the GC receptor (GCR). METHODS Blood was collected from 10 COPD and 10 healthy aged-matched controls. Flow cytometry was applied to assess intracellular pro-inflammatory cytokines, CD28, Pgp1, GCR, steroid binding and relative cytoplasm/nuclear GCR by CD28+ and CD28null T, NKT-like cells. GCR localization was confirmed by fluorescent microscopy. RESULTS COPD was associated with increased numbers of CD28nullCD8+ T and NKT-like cells. Loss of CD28 was associated with an increased percentage of T and NKT-like cells producing IFNγ or TNFα and associated with a loss of GCR and Dex-Fluor staining but unchanged Pgp1. There was a significant loss of GCR in CD8 + CD28null compared with CD8 + CD28+ T and NKT-like cells from both COPD and controls (eg, mean ± SEM 8 ± 3% GCR + CD8 + CD28null T-cells vs 49 ± 5% GCR + CD8 + CD28+ T-cells in COPD). There was a significant negative correlation between GCR expression and IFNγ and TNFα production by T and NKT-like cells(eg, COPD: T-cell IFNγ R = −.615; ) and with FEV1 in COPD (R = −.777). CONCLUSIONS COPD is associated with loss of GCR in senescent CD28null and NKT-like cells suggesting alternative treatment options to GC are required to inhibit these pro-inflammatory/cytotoxic cells.Greg Hodge, Hubertus Jersmann, Hai B Tran, Mark Holmes, Paul N Reynolds, and Sandra Hodg
Lymphocyte senescence in COPD is associated with decreased histone deacetylase 2 expression by pro-inflammatory lymphocytes
Histone acetyltransferases (HAT) and histone deacetylases (HDAC) are enzymes that upregulate and down-regulate pro-inflammatory gene transcription respectively. HDAC2 is required by corticosteroids to switch off activated inflammatory genes and is reduced in lung macrophages in COPD. We have shown that COPD patients have increased steroid resistant CD28null (senescent) pro-inflammatory T and NKT-like peripheral blood cells (particularly CD8+ subsets) and we hypothesized that these changes would be associated with a loss of HDAC2 from these senescent pro-inflammatory lymphocytes.Blood was collected from 10 COPD and 10 aged-matched controls. Intracellular pro-inflammatory cytokines, IFNγ and TNFα, and expression of CD28, HDAC2 and HAT, were determined in lymphocyte subsets in the presence of ± 5 mg/ml theophylline (HDAC2 activator), 10 μM prednisolone and 2.5 ng/ml cyclosporine A (immunosuppressant), using flow cytometry.There was a loss of HDAC2 from CD28null CD8+ T and NKT-like cells in COPD. There was a significant negative correlation between HDAC2 expression and the percentage of CD28null CD8+ T and NKT-like cells producing IFNγ or TNFα in all subjects (eg, COPD: R = -.763, p < 0.001 for T-cell IFNγ). There was a synergistic upregulation of HDAC2 and associated decrease in pro-inflammatory cytokine production in CD28nullCD8+ T and NKT-like cells in the presence of 5 mg/L theophylline + 10(-6) M prednisolone or 2.5 ng/mL cyclosporine A (CsA).Lymphocyte senescence in COPD is associated with loss of HDAC2 in CD28nullCD8+ T and NKT-like cells. Alternative treatment options such as combined theophylline with low-dose CsA, that inhibit these pro-inflammatory cells, may reduce systemic inflammation in COPD.Greg Hodge, Hubertus Jersmann, Hai B. Tran, Eugene Roscioli, Mark Holmes, Paul N. Reynolds and Sandra Hodg
Bushfire smoke is pro-inflammatory and suppresses macrophage phagocytic function
Bushfires are increasing in frequency and severity worldwide. Bushfire smoke contains organic/inorganic compounds including aldehydes and acrolein. We described suppressive effects of tobacco smoke on the phagocytic capacity of airway macrophages, linked to secondary necrosis of uncleared apoptotic epithelial cells, persistence of non-typeable H. influenzae (NTHi), and inflammation. We hypothesised that bushfire smoke extract (BFSE) would similarly impair macrophage function. THP-1 or monocyte-derived macrophages (MDM) were exposed to 1-10% BFSE prepared from foliage of 5 common Australian native plants (genus Acacia or Eucalyptus), or 10% cigarette smoke extract (CSE). Phagocytic recognition receptors were measured by flow cytometry; pro-inflammatory cytokines and caspase 1 by immunofluorescence or cytometric bead array; viability by LDH assay; and capsase-3/PARP by western blot. BFSE significantly decreased phagocytosis of apoptotic cells or NTHi by both THP-1 macrophages and MDM vs air control, consistent with the effects of CSE. BFSE significantly decreased MDM expression of CD36, CD44, SR-A1, CD206 and TLR-2 and increased active IL-1β, caspase-1 and secreted IL-8. BFSE dose-dependently decreased THP-1 macrophage viability (5-fold increase in LDH at 10%) and significantly increased active caspase-3. BFSE impairs macrophage function to a similar extent as CSE, highlighting the need for further research, especially in patients with pre-existing lung disease.Rhys Hamon, Hai B. Tran, Eugene Roscioli, Miranda Ween, Hubertus Jersmann, Sandra Hodg
Predictors of non-cystic fibrosis bronchiectasis in Indigenous adult residents of central Australia: results of a case-control study
The human T-cell leukaemia virus type 1 (HTLV-1) is associated with pulmonary inflammation. Indigenous Australians in central Australia have a very high prevalence of HTLV-1 infection and we hypothesised that this might contribute to high rates of bronchiectasis in this population. 80 Indigenous adults with confirmed bronchiectasis, each matched by age, sex and language to two controls without bronchiectasis, were recruited. Case notes and chest imaging were reviewed, HTLV-1 serology and the number of peripheral blood leukocytes (PBLs) infected with HTLV-1 (pro-viral load (PVL)) were determined, and radiological abnormality scores were calculated. Participants were followed for a mean±sd of 1.14±0.86 years and causes of death were determined. Median (interquartile range) HTLV-1 PVL for cases was 8-fold higher than controls (cases 213.8 (19.7-3776.3) copies per 10⁵ PBLs versus controls 26.6 (0.9-361) copies per 10⁵ PBLs; p=0.002). Radiological abnormality scores were higher for cases with HTLV-1 PVL ≥1000 copies per 10⁵ PBLs and no cause of bronchiectasis other than HTLV-1 infection. Major predictors of bronchiectasis were prior severe lower respiratory tract infection (adjusted OR (aOR) 17.83, 95% CI 4.51-70.49; p<0.001) and an HTLV-1 PVL ≥1000 copies per 10⁵ PBLs (aOR 12.41, 95% CI 3.84-40.15; p<0.001). Bronchiectasis (aOR 4.27, 95% CI 2.04-8.94; p<0.001) and HTLV-1 PVL ≥1000 copies per 105 PBLs (aOR 3.69, 95% CI 1.11-12.27; p=0.033) predicted death. High HTLV-1 PVLs are associated with bronchiectasis and with more extensive radiological abnormalities, which may result from HTLV-1-mediated airway inflammation.Lloyd Einsiedel, Hai Pham, Virginia Au, Saba Hatami, Kim Wilson, Tim Spelman and Hubertus Jersman
Zinc deficiency as a codeterminant for airway epithelial barrier dysfunction in an ex vivo model of COPD
There is now convincing evidence that the airway epithelium drives the pathogenesis of COPD. A major aspect of this is the disease-related reduction in barrier function that is potentiated by dysregulation of tight junction (TJ) protein complexes. However, a significant number of studies using in vitro smoke exposure models have not observed alterations in barrier permeability. We have previously shown that zinc (Zn) is an influential cytoprotective factor for the airway epithelium, and its depletion by cigarette smoke produces disease-related modifications consistent with inflammatory changes in COPD. We hypothesized that Zn deficiency is a significant co-stimulus with cigarette smoke extract (CSE) for potentiating the leaky barrier phenotype exhibited in COPD. We employed an ex vivo model of differentiated human airway epithelium exposed to Zn depletion and CSE to determine the contribution of Zn in maintaining normal epithelial permeability. Western blot analysis demonstrated a significant downregulation of the TJ proteins such as ZO-1 (-1.93-fold, P<0.05) and Claudin-1 (-3.37-fold, P<0.01) with the combination exposure. Assessment of barrier function via paracellular ionic conductance and tracer permeability also showed that Zn depletion was an important factor, which potentiated an increase in epithelial permeability (P<0.001 for both) compared to Zn depletion or CSE exposures in isolation. Visual inspection of the epithelium using transmission electron microscopy revealed a marked reduction in junction complexes between the adjacent airway epithelial cells treated with a combination of Zn depletion and CSE. These observations identify Zn deficiency as a significant codeterminant with CSE as a factor leading to an increase in airway epithelial permeability. Hence, as Zn dyshomeostasis has been reported in the airway epithelium exposed to chronic cigarette smoke and inflammation, targeting these phenomena may represent a promising strategy to ameliorate the leaky barrier phenotype that is synonymous with COPD.Eugene Roscioli, Hubertus PA Jersmann, Susan Lester, Arash Badiei, Andrew Fon, Peter Zalewski, Sandra Hodg
Identification of tuberculosis-associated proteins in whole blood supernatant
<p>Abstract</p> <p>Background</p> <p>Biological parameters are useful tools for understanding and monitoring complicated disease processes. In this study, we attempted to identify proteins associated with active pulmonary tuberculosis (TB) using a proteomic approach.</p> <p>Methods</p> <p>To assess TB-associated changes in the composition of human proteins, whole blood supernatants were collected from patients with active TB and healthy control subjects. Two-dimensional difference gel electrophoresis (2D-DIGE) was performed to analyze proteins with high molecular weights (approximately >20 kDa). Baseline protein levels were initially compared between patients with active TB and control subjects. Possible changes of protein patterns in active TB were also compared <it>ex vivo </it>between whole blood samples incubated with <it>Mycobacterium tuberculosis </it>(<it>Mtb</it>)-specific antigens (stimulated condition) and under unstimulated conditions. Immunoblot and enzyme-linked immunosorbent assays (ELISA) were performed to confirm differences in identified proteins.</p> <p>Results</p> <p>Under the baseline condition, we found that the levels of retinol-binding protein 4 (RBP4), fetuin-A (also called α-HS-glycoprotein), and vitamin D-binding protein differed between patients with active TB and control subjects on 2D gels. Immunoblotting results confirmed differential expression of RBP4 and fetuin-A. ELISA results further confirmed significantly lower levels of these two proteins in samples from patients with active TB than in control subjects (<it>P </it>< 0.0001). <it>Mtb</it>-specific antigen stimulation <it>ex vivo </it>altered clusterin expression in whole blood samples collected from patients with active TB.</p> <p>Conclusions</p> <p>We identified TB-associated proteins in whole blood supernatants. The dynamics of protein expression during disease progression may improve our understanding of the pathogenesis of TB.</p
Potential link between the Sphingosine-1-Phosphate (S1P) system and defective alveolar macrophage phagocytic function in Chronic Obstructive Pulmonary Disease (COPD)
We previously reported that alveolar macrophages from patients with chronic obstructive pulmonary disease (COPD) are defective in their ability to phagocytose apoptotic cells, with a similar defect in response to cigarette smoke. The exact mechanisms for this defect are unknown. Sphingolipids including ceramide, sphingosine and sphingosine-1-phosphate (S1P) are involved in diverse cellular processes and we hypothesised that a comprehensive analysis of this system in alveolar macrophages in COPD may help to delineate the reasons for defective phagocytic function.We compared mRNA expression of sphingosine kinases (SPHK1/2), S1P receptors (S1PR1-5) and S1P-degrading enzymes (SGPP1, SGPP2, SGPL1) in bronchoalveolar lavage-derived alveolar macrophages from 10 healthy controls, 7 healthy smokers and 20 COPD patients (10 current- and 10 ex-smokers) using Real-Time PCR. Phagocytosis of apoptotic cells was investigated using flow cytometry. Functional associations were assessed between sphingosine signalling system components and alveolar macrophage phagocytic ability in COPD. To elucidate functional effects of increased S1PR5 on macrophage phagocytic ability, we performed the phagocytosis assay in the presence of varying concentrations of suramin, an antagonist of S1PR3 and S1PR5. The effects of cigarette smoking on the S1P system were investigated using a THP-1 macrophage cell line model.We found significant increases in SPHK1/2 (3.4- and 2.1-fold increases respectively), S1PR2 and 5 (4.3- and 14.6-fold increases respectively), and SGPL1 (4.5-fold increase) in COPD vs. controls. S1PR5 and SGPL1 expression was unaffected by smoking status, suggesting a COPD "disease effect" rather than smoke effect per se. Significant associations were noted between S1PR5 and both lung function and phagocytosis. Cigarette smoke extract significantly increased mRNA expression of SPHK1, SPHK2, S1PR2 and S1PR5 by THP-1 macrophages, confirming the results in patient-derived macrophages. Antagonising SIPR5 significantly improved phagocytosis.Our results suggest a potential link between the S1P signalling system and defective macrophage phagocytic function in COPD and advise therapeutic targets.Jameel Barnawi, Hai Tran, Hubertus Jersmann, Stuart Pitson, Eugene Roscioli, Greg Hodge, Robyn Meech, Rainer Haberberger, Sandra Hodg
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