Host-Pathogen Interaction in the Lung of Patients Infected with <em>Pseudomonas aeruginosa</em>

Pseudomonas aeruginosa is an opportunistic bacterium that can proliferate in the soil, water, and even humans if they are immunologically depressed. During lung infections, P. aeruginosa goes through significant morphological changes turning into the mucoid form after which its eradication becomes almost impossible. Within this chapter, we explore the bioenergetics changes produced within P. aeruginosa during infections in humans and the metabolic pathways that are involved in those changes that lead to chronic infection

Consequences of cystic fibrosis transmembrane regulator mutations on inflammatory cells

Recent studies in cystic fibrosis (CF) transmembrane regulator (CFTR) mutations and function have shed light on its involvement in disease progression. The extent of cell and tissue distribution of CFTR facilitates systemic dysfunction of ion transport in patients carrying a mutation in CFTR, however, its incidences as cofounding risk factor to develop other diseases is not well studied. In this review we differentiate the dysfunctions driven by CFTR mutations in cell of the immune system and their role in CF progression and examine the types of medical treatments available to patients up to date.Fil: Grumelli, Sandra. Universidad Católica de Córdoba; ArgentinaFil: Islan, German Abel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; ArgentinaFil: Castro, Guillermo Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentin

Consequences of cystic fibrosis transmembrane regulator mutations on inflammatory cells

Recent studies in cystic fibrosis (CF) transmembrane regulator (CFTR) mutations and function have shed light on its involvement in disease progression. The extent of cell and tissue distribution of CFTR facilitates systemic dysfunction of ion transport in patients carrying a mutation in CFTR, however, its incidences as cofounding risk factor to develop other diseases is not well studied. In this review we differentiate the dysfunctions driven by CFTR mutations in cell of the immune system and their role in CF progression and examine the types of medical treatments available to patients up to date.Centro de Investigación y Desarrollo en Fermentaciones Industriale

CD46 Protects against Chronic Obstructive Pulmonary Disease

BACKGROUND: Chronic obstructive pulmonary disease and emphysema develops in 15% of ex-smokers despite sustained quitting, while 10% are free of emphysema or severe lung obstruction. The cause of the incapacity of the immune system to clear the inflammation in the first group remains unclear. METHODS AND FINDINGS: We searched genes that were protecting ex-smokers without emphysema, using microarrays on portions of human lungs surgically removed; we found that loss of lung function in patients with chronic obstructive pulmonary disease and emphysema was associated with a lower expression of CD46 and verified this finding by qRT-PCR and flow cytometry. Also, there was a significant association among decreased CD46(+) cells with decreased CD4(+)T cells, apoptosis mediator CD95 and increased CD8(+)T cells that were protecting patients without emphysema or severe chronic obstructive pulmonary disease. CD46 not only regulates the production of T regulatory cells, which suppresses CD8(+)T cell proliferation, but also the complement cascade by degradation of C3b. These results were replicated in the murine smoking model, which showed increased C5a (produced by C3b) that suppressed IL12 mediated bias to T helper 1 cells and elastin co-precipitation with C3b, suggesting that elastin could be presented as an antigen. Thus, using ELISA from elastin peptides, we verified that 43% of the patients with severe early onset of chronic obstructive pulmonary disease tested positive for IgG to elastin in their serum compared to healthy controls. CONCLUSIONS: These data suggest that higher expression of CD46 in the lungs of ex-smoker protects them from emphysema and chronic obstructive pulmonary disease by clearing the inflammation impeding the proliferation of CD8(+) T cells and necrosis, achieved by production of T regulatory cells and degradation of C3b; restraining the complement cascade favors apoptosis over necrosis, protecting them from autoimmunity and chronic inflammation

An Immune Basis for Lung Parenchymal Destruction in Chronic Obstructive Pulmonary Disease and Emphysema

BACKGROUND: Chronic obstructive pulmonary disease and emphysema are a frequent result of long-term smoking, but the exact mechanisms, specifically which types of cells are associated with the lung destruction, are unclear. METHODS AND FINDINGS: We studied different subsets of lymphocytes taken from portions of human lungs removed surgically to find out which lymphocytes were the most frequent, which cell-surface markers these lymphocytes expressed, and whether the lymphocytes secreted any specific factors that could be associated with disease. We found that loss of lung function in patients with chronic obstructive pulmonary disease and emphysema was associated with a high percentage of CD4(+) and CD8(+) T lymphocytes that expressed chemokine receptors CCR5 and CXCR3 (both markers of T helper 1 cells), but not CCR3 or CCR4 (markers of T helper 2 cells). Lung lymphocytes in patients with chronic obstructive pulmonary disease and emphysema secrete more interferon gamma—often associated with T helper 1 cells—and interferon-inducible protein 10 and monokine induced by interferon, both of which bind to CXCR3 and are involved in attracting T helper 1 cells. In response to interferon-inducible protein 10 and monokine induced by interferon, but not interferon gamma, lung macrophages secreted macrophage metalloelastase (matrix metalloproteinase-12), a potent elastin-degrading enzyme that causes tissue destruction and which has been linked to emphysema. CONCLUSIONS: These data suggest that Th1 lymphoctytes in the lungs of people with smoking-related damage drive progression of emphysema through CXCR3 ligands, interferon-inducible protein 10, and monokine induced by interferon

Inflammation in the murine smoking model.

<p>(A) Increased expression of CD46 in the lung tissue of no smoker mice compared to smoke exposed mice determined by IHC, arrow heads, and by western western blot on lung tissue homogenates of control mice or smoke-exposed mice (p = 0.02, n = 4, n = 4). (B) Increased deposition of C3b on lung tissue of control mice (n = 3) compared to smoke- exposed mice at 4 and 24 weeks (n = 3) determined by Western blot. Middle plot, immunoprecipitation of C3b from lung homogenate shows a significant increase of C3b deposition upon smoke exposure (p = 0.05). Elastin was stained and detected after stripping the membrane, showing significant increased co-precipitation with C3b (p = 0.01). Student t-test two tails was used to compare both groups; values in the plots represent average ± SD.</p

Protective genes.

a<p>mRNA expression tested in the same participants by microarray and quantitative RT-PCR which had either ^b lung resection for treatment of small peripheral cancer (n = 5); or ^c lung volume reduction surgery for emphysema (non-cancer, n = 4).</p>d<p>Values are expressed as average ± SD, P values are relative to control, calculated using two tailed T students test.</p>*<p>, p<0.0001;</p>†<p>, p<0.001;</p>‡<p>, p<0.01;</p>§<p>, p<0.05.</p

Clinical and Demographic Characteristics of Participants.

a<p>Determined by Ct scan.</p>b<p>Lung Volume Reduction Surgery (LVRS).</p>c<p>Percentage of Forced expiratory volume (FEV1) in one second is *significantly different (p<0.05) for the end-stage group compared to the control group.</p>d<p>Packs per years (PPY), quitting time (QT) and age values are similar among the three groups.</p>e<p>Quitting time: continue time without smoking since quitting.</p>f<p>, The patients had no history of allergy or asthma and had not received oral/systemic or inhaled corticosteroids during the last six months. At the time of study, all patients were free of acute symptoms suggestive of upper or lower respiratory tract infection in the 6 weeks preceding the study.</p

Molecular cross-talk of the protective genes.

<p>(A) CD46 coupling with CD3 activates the transcription factor ubiquitously transcribed tetratricopeptide (UTX), which interacts with signal transducer and activator of transcription 1 (STAT1) both translocate to the nucleus to activate proliferation of CD4⁺T cells. T cell receptor activates Bcl-2 that inhibits cytochrome C (Cyto C) released by chloride intracellular channel 4 (CLIC4), which positively regulates Fas Ligand receptor (CD95) mediated activation of Caspase 8 (Casp 8) and apoptosis. Homeodomain interacting protein kinase 3 (HIPK3) phophorilates CD95, and HuR stabilizes CD95 mRNA also positively regulates it. While 2 negative regulators of CD95 are methionine adenosyl transferase II, alpha (MATII) and hepatocyte growth factor receptor (HFGR). Red font signifies protective gene, black arrow apoptosis activation, black bold arrow apoptosis inhibition. Red arrow, proliferation pathway. Red proteins are kinases; blue, transcription factors; light brown, cell surface receptors. (B) Total CD46 expression on the surface of lung cells of patients (n = 14) significantly correlates with their FEV1% in a linear regression using minimum square approximation, with a coefficient r = 0.563 and a goodness of fit p = 0.036. The FasL receptor, CD95, protein expression on the same patients, also, positively correlates with FEV1% with an r = 0.711 and a goodness of fit p = 0.006. There is a significative linear association between cells surface proteins expression, CD46⁺ and CD95⁺ (r = 0.666, p = 0.012). Right top plot, total lung lymphocytes CD4⁺ plus CD8⁺ has a constant number in the lung parenchyma despite their lung FEV1% change with disease progression (r = 0.107, p = 0.6332, n = 22) although there is a significant change in the number of CD4⁺ and CD8⁺ T cells. Right middle plot, in the same patients group, CD4⁺T cells (black circles) correlates directly with the FEV1% (r = 0.549, slope = 0.24, p = 0.008, n = 22), conversely CD8⁺ T cells (red circles) inversely correlates with FEV1% increasing its number with disease progression (r = 0.480, slope  = −0.329, p = 0.024). Bottom right plot shows a direct correlation between FEV1% and depletion of CD4⁺ with increment of CD8⁺ T cells (slope = 8.4, r = 0.726, p = 0.0002). (C) There is a remarkable association among CD46⁺ decrement and CD4⁺/CD8⁺ ratio of T cells, r = 0.896 p = 0.006, n = 7. (D) Increased IgG to elastin in early-onset COPD (EO-COPD) patients, relative to normal controls, tested in n = 21 and n = 28, respectively, plot represents the patients that give signal above the threshold n = 9 for both EO-COPD and control with a significant increased in the diseased group p = 0.038, determined by Mann-Whitney test, values represent median ± SD.</p

Quantification of CD46 levels.

<p>(A) Forward and side scatter plot of lung cells. Circles show the lymphocyte, macrophages and neutrophil populations. To the right a single color histograms showing expression of receptor CD46 from representative control, emphysema and end-stage participants. Pooled data from all participants (control, n = 4; emphysema, n = 4, end-stage n = 5) showing percent (median±SD) of total lung neutrophils, and macrophages expressing CD46; Cumulative values for lymphocytes showed a significative decrease (control, n = 6; emphysema, n = 7, end-stage n = 6, p<0.05) more patient were included with the same lung characteristics. (B) Gene expression of Casp 8, on the same patients, determined by qRT-PCR (median±SD) on emphysema patients with (n = 5) and without cancer (n = 4) shows no different expression level due to cancer away from the emphysemic region (p = 1). Mann-Whitney test was used to determine significant difference.</p