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Structural and metabolic alterations in erythrocytes play an important role in the pathophysiology of Chronic Obstructive Pulmonary Disease (COPD). Whether these dysfunctions are related to the modulation of erythrocyte membrane proteins in patients diagnosed with COPD remains to be determined. Herein, a comparative proteomic profiling of the erythrocyte membrane fraction isolated from peripheral blood of smokers diagnosed with COPD and smokers with no COPD was performed using differential (16)O/(18)O stable isotope labeling. A total of 219 proteins were quantified as being significantly differentially expressed within the erythrocyte membrane proteomes of smokers with COPD and healthy smokers. Functional pathway analysis showed that the most enriched biofunctions were related to cell-to-cell signaling and interaction, hematological system development, immune response, oxidative stress and cytoskeleton. Chorein (VPS13A), a cytoskeleton related protein whose defects had been associated with the presence of cell membrane deformation of circulating erythrocytes was found to be down-regulated in the membrane fraction of erythrocytes obtained from COPD patients. Methemoglobin reductase (CYB5R3) was also found to be underexpressed in these cells, suggesting that COPD patients may be at higher risk for developing methemoglobinemia. This article is part of a Special Issue entitled: Integrated omics., (Copyright © 2012 Elsevier B.V. All rights reserved.)

A comprehensive proteomic profiling of nasal epithelium (NE) is described. This study relies on simple subcellular fractionation used to obtain soluble- and membrane-enriched fractions followed by 2-dimensional liquid chromatography (2D-LC) separation and tandem mass spectrometry (MS/MS). The cells were collected using a brushing technique applied on NE of clinically evaluated volunteers. Subsequently, the soluble- and the membrane-protein enriched fractions were prepared and analyzed in parallel using 2D-LC-MS/MS. In a set of 1482 identified proteins, 947 (63.9%) proteins were found to be associated to membrane fraction. Grand average hydropathy value index (GRAVY) analysis, the transmembrane protein mapping and annotations of primary location deposited in the Human Protein Reference Database (HPRD) confirmed an enrichment of hydrophobic proteins on this dataset. Ingenuity Pathway Analysis (IPA) of soluble fraction revealed an enrichment of molecular and cellular functions associated with cell death, protein folding and drug metabolism while in membrane fraction showed an enrichment of functions associated with molecular transport, protein trafficking and cell-to-cell signaling and interaction. The IPA showed similar enrichment of functions associated with cellular growth and proliferation in both soluble and membrane subproteomes. This finding was in agreement with protein content analysis using exponentially modified protein abundance index (emPAI). A comparison of our data with previously published studies focusing on respiratory tract epithelium revealed similarities related to identification of proteins associated with physical barrier function and immunological defence. In summary, we extended the NE molecular profile by identifying and characterizing proteins associated to pivotal functions of a respiratory epithelium, including the control of fluid volume and ionic composition at the airways' surface, physical barrier maintenance, detoxification and immunological defence. The extent of similarities supports the applicability of a less invasive analysis of NE to assess prognosis and treatment response of lung diseases such as asthma, cystic fibrosis and chronic obstructive pulmonary disease., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The following report provides an overview of the discussions and outcome of the EuPA General Council meeting that took place in Estoril 20-21 October 2010. During the annual meeting future policy and action plans in a variety of areas are decided. Several important points were decided upon during this meeting including the expansion of the EuPA Executive Committee by introducing a new EuPA committee - EuPA Developments - that will initially spearhead activities in standardisation, imaging ms and biobanking. The EuPA General Council also invited Russia as its 17th member. More details about these and additional activities are presented in the article., (Copyright © 2011. Published by Elsevier B.V.)

Complementary 2D-PAGE and 'shotgun' LC-MS/MS approaches were combined to identify medium and low-abundant proteins in sera of Cystic Fibrosis (CF) patients (mild or severe pulmonary disease) in comparison with healthy CF-carrier and non-CF carrier individuals aiming to gain deeper insights into the pathogenesis of this multifactorial genetic disease. 78 differentially expressed spots were identified from 2D-PAGE proteome profiling yielding 28 identifications and postulating the existence of post-translation modifications (PTM). The 'shotgun' approach highlighted altered levels of proteins actively involved in CF: abnormal tissue/airway remodeling, protease/antiprotease imbalance, innate immune dysfunction, chronic inflammation, nutritional imbalance and Pseudomonas aeruginosa colonization. Members of the apolipoproteins family (VDBP, ApoA-I, and ApoB) presented gradually lower expression from non-CF to CF-carrier individuals and from those to CF patients, results validated by an independent assay. The multifunctional enzyme NDKB was identified only in the CF group and independently validated by WB. Its functions account for ion sensor in epithelial cells, pancreatic secretion, neutrophil-mediated inflammation and energy production, highlighting its physiological significance in the context of CF. Complementary proteomics-based approaches are reliable tools to reveal pathways and circulating proteins actively involved in a heterogeneous disease such as CF., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Current clinical, laboratory or radiological parameters cannot accurately diagnose or predict disease outcomes in a range of autoimmune disorders. Biomarkers which can diagnose at an earlier time point, predict outcome or help guide therapeutic strategies in autoimmune diseases could improve clinical management of this broad group of debilitating disorders. Additionally, there is a growing need for a deeper understanding of multi-factorial autoimmune disorders. Proteomic platforms offering a multiplex approach are more likely to reflect the complexity of autoimmune disease processes. Findings from proteomic based studies of three distinct autoimmune diseases are presented and strategies compared. It is the authors' view that such approaches are likely to be fruitful in the movement of autoimmune disease treatment away from reactive decisions and towards a preventative stand point., (Crown Copyright 2009. Published by Elsevier B.V. All rights reserved.)

To gain insight into the proteins potentially involved in the low temperature-induced F508del-CFTR rescue process, we have explored by two-dimensional electrophoresis (2DE) the proteome of BHK cell lines expressing wt or F508del-CFTR, grown at 37 degrees C or 26 degrees C/24h or 26 degrees C/48h followed by 3h of metabolic labelling with [(35)S]-methionine. A set of 139 protein spots (yielding 125 mass spectrometry identifications) was identified as differentially expressed (p ANOVA<0.05) among the six phenotypic groups analysed. The data analysis suggests that the unfolded protein response (UPR) induction and some cell-metabolism repression are the major cold-shock responses that may generate a favourable cellular environment to promote F508del-CFTR rescue. Down-regulation of proteasome regulatory PA28 and/or COP9 signalosome subunit, both involved in CFTR degradation, could also be a relevant cold-shock-induced condition for F508de-CFTR rescue. Moreover, cold-shock may promote the reestablishment of some proteostasis imbalance associated with over-expression of F508del-CFTR. In BHK-F508del cells, the deregulation of RACK1, a protein described to be important for stable expression of CFTR in the plasma membrane, is partially repaired after low temperature treatment. Together these findings give new insights about F508del-CFTR rescue by low temperature treatment and the proteins involved could ultimately constitute potential therapeutic targets in CF disease.

Hepatitis delta virus (HDV) infects human hepatocytes already infected with the hepatitis B virus increasing about ten fold the risk of cirrhosis and fulminant hepatitis. The lack of an appropriate cell culture system capable of supporting virus replication has so far impaired the detailed investigation of the HDV biology including the identification of host factors involved in pathogenesis. Here, we made use of a HDV cDNA stably transfected cell line, Huh7-D12, in a proteomic approach to identify the changes in the protein expression profiles in human liver cells that arise as a consequence of HDV replication. Total protein extracts from Huh7-D12 cells and of the corresponding non transfected human liver carcinoma cell line, Huh7, were separated by 2-DE. Differentially expressed spots were identified by MALDI-TOF followed by database searching. We identified 23 differentially expressed proteins of which 15 were down regulated and 8 up regulated in Huh7-D12 cells. These proteins were found to be involved in different cellular pathways. The down regulation of the histone H1-binding protein and of triosephosphate isomerase was confirmed by Real time PCR, and the up regulation of the La protein and lamin A/C was validated by western blot.

Hepatitis delta virus (HDV) infection of human hepatocytes infected with the hepatitis B virus (HBV) is associated with increased liver damage and risk of fulminant disease. Although considerable progress has been made towards the elucidation of the mechanisms of HDV replication and pathogenesis, little is still known about the host factors involved in the different steps of the replication cycle. Here, we made use of a proteomic approach to analyse the global alterations in protein expression that arise in human hepatocytes separately transfected with each of the HDV components. Huh7 cells were transiently transfected with plasmids that code for the small delta antigen (S-HDAg), large delta antigen (L-HDAg), genomic RNA (gRNA), and antigenomic RNA (agRNA), respectively. Total protein extracts were separated by 2-DE and differentially expressed spots were identified by MALDI-TOF followed by database searching. We identified 32 proteins known to be involved in different pathways namely nucleic acid metabolism, protein metabolism, transport, signal transduction, apoptosis, and cell growth. Moreover, the down regulation of hnRNP D, HSP105, and triosephosphate isomerase was further confirmed by Real time PCR.