Morph-specific protein patterns in the femoral gland secretions of a colour polymorphic lizard.

Colour polymorphism occurs when two or more genetically-based colour morphs permanently coexist within an interbreeding population. Colouration is usually associated to other life-history traits (ecological, physiological, behavioural, reproductive …) of the bearer, thus being the phenotypic marker of such set of genetic features. This visual badge may be used to inform conspecifics and to drive those decision making processes which may contribute maintaining colour polymorphism under sexual selection context. The importance of such information suggests that other communication modalities should be recruited to ensure its transfer in case visual cues were insufficient. Here, for the first time, we investigated the potential role of proteins from femoral gland secretions in signalling colour morph in a polymorphic lizard. As proteins are thought to convey identity-related information, they represent the ideal cues to build up the chemical modality used to badge colour morphs. We found strong evidence for the occurrence of morph-specific protein profiles in the three main colour-morphs of the common wall lizard, which showed both qualitative and quantitative differences in protein expression. As lizards are able to detect proteins by tongue-flicking and vomeronasal organ, this result support the hypothesis that colour polymorphic lizards may use a multimodal signal to inform about colour-morph.

A Pilot Study to Investigate the Balance between Proteases and α1-Antitrypsin in Bronchoalveolar Lavage Fluid of Lung Transplant Recipients.

: The neutrophilic component in bronchiolitis obliterans syndrome (BOS, the main form of chronic lung rejection), plays a crucial role in the pathogenesis and maintenance of the disorder. Human Neutrophil Elastase (HNE), a serine protease responsible of elastin degradation whose action is counteracted by α1-antitrypsin (AAT), a serum inhibitor specific for this protease. This work aimed to investigate the relationship between HNE and AAT in bronchoalveolar lavage fluid (BALf) from stable lung transplant recipients and BOS patients to understand whether the imbalance between proteases and inhibitors is relevant to the development of BOS. To reach this goal a multidisciplinary procedure was applied which included: (i) the use of electrophoresis/western blotting coupled with liquid chromatography-mass spectrometric analysis; (ii) the functional evaluation of the residual antiprotease activity, and (iii) a neutrophil count.

Searching for biomarkers of chronic obstructive pulmonary disease using proteomics: The current state.

Detection of proteins which may be potential biomarkers of disorders represents a big step forward in understanding the molecular mechanisms that underlie pathological processes. In this context proteomics plays the important role of opening a path for the identification of molecular signatures that can potentially assist in early diagnosis of several clinical disturbances. Aim of this report is to provide an overview of the wide variety of proteomic strategies that have been applied to the investigation of chronic obstructive pulmonary disease (COPD), a severe disorder that causes an irreversible damage to the lungs and for which there is no cure yet. The results in this area published over the past decade show that proteomics indeed has the ability of monitoring alterations in expression profiles of proteins from fluids/tissues of patients affected by COPD and healthy controls. However, these data also suggest that proteomics, while being an attractive tool for the identification of novel pathological mediators of COPD, remains a technique mainly generated and developed in research laboratories. Great efforts dedicated to the validation of these biological signatures will result in the proof of their clinical utility.

Could Proteomics Become a Future Useful Tool to Shed Light on the Mechanisms of Rare Neurodegenerative Disorders?

Very often the clinical features of rare neurodegenerative disorders overlap with those of other, more common clinical disturbances. As a consequence, not only the true incidence of these disorders is underestimated, but many patients also experience a significant delay before a definitive diagnosis. Under this scenario, it appears clear that any accurate tool producing information about the pathological mechanisms of these disorders would offer a novel context for their precise identification by strongly enhancing the interpretation of symptoms. With the advent of proteomics, detection and identification of proteins in different organs/tissues, aimed at understanding whether they represent an attractive tool for monitoring alterations in these districts, has become an area of increasing interest. The aim of this report is to provide an overview of the most recent applications of proteomics as a new strategy for identifying biomarkers with a clinical utility for the investigation of rare neurodegenerative disorders.

Advances in the analysis of "less-conventional" human body fluids: An overview of the CE- and HPLC-MS applications in the years 2015-2017.

Aim of this article is to focus the attention of the reader on the application of CE/MS and LC/MS to the analysis of human body fluids not currently used for the diagnosis of disorders and, for this reason, catalogued as "less/nonconventional" fluids, that is, tears, nasal secretions, cerumen, bronchoalveolar lavage fluid, sputum, exhaled breath condensate, nipple aspirate, breast milk, amniotic fluid, bile, seminal plasma, liposuction aspirate fluid, and synovial fluid. The pool of articles presented in this report demonstrates that, rather than being neglected, these fluids are an important resource for the evaluation of possible pathologic conditions. Thus, being a sort of mirror that reflects the normal internal characteristics and disease state of an individual, they benefit of an increasing appreciation. This review follows a previous report of this series and covers the latest developments in this field that have been published in specialist journals in the years 2015-2017.

1H NMR To Evaluate the Metabolome of Bronchoalveolar Lavage Fluid (BALf) in Bronchiolitis Obliterans Syndrome (BOS): Toward the Development of a New Approach for Biomarker Identification.

This report describes the application of NMR spectroscopy to the profiling of metabolites in bronchoalveolar lavage fluid (BALf) of lung transplant recipients without bronchiolitis obliterans syndrome (BOS) (stable, S, n = 10), and with BOS at different degrees of severity (BOS 0p, n = 10; BOS I, n = 10). Through the fine-tuning of a number of parameters concerning both sample preparation/processing and variations of spectra acquisition modes, an efficient and reproducible protocol was designed for the screening of metabolites in a pulmonary fluid that should reflect the status of airway inflammation/injury. Exploiting the combination of mono- and bidimensional NMR experiments, 38 polar metabolites, including amino acids, Krebs cycle intermediates, mono- and disaccharides, nucleotides, and phospholipid precursors, were unequivocally identified. To determine which signature could be correlated with the onset of BOS, the metabolites' content of the above recipients was analyzed by multivariate (PCA and OPLS-DA) statistical methods. PCA analysis (almost) totally differentiated S from BOS I, and this discrimination was significantly improved by the application of OPLS-DA, whose model was characterized by excellent fit and prediction values (R2 = 0.99 and Q2 = 0.88). The analysis of S vs BOS 0p and of BOS 0p vs BOS I samples showed a clear discrimination of considered cohorts, although with a poorer efficiency compared to those measured for S vs BOS I patients. The data shown in this work assess the suitability of the NMR approach in monitoring different pathological lung conditions.

Do the complementarities of electrokinetic and chromatographic procedures represent the "Swiss knife" in proteomic investigation? An overview of the literature in the past decade.

This report reviews the literature of the past decade dealing with the combination of electrokinetic and chromatographic strategies in the proteomic field. Aim of this article is to highlight how the application of complementary techniques may contribute to substantially improve protein identification. Several studies here considered demonstrate that exploring the combination of these approaches can be a strategy to enrich the extent of proteomic information achieved from a sample. The coupling of "top-down" and "bottom-up" proteomics may result in the generation of a hybrid analytical tool, very efficient not only for large-scale profiling of complex proteomes but also for studying specific subproteomes. The range of applications described, while evidencing a continuous boost in the imagination of researchers for developing new combinations of methods for protein separation, also underlines the adaptability of these techniques to a wide variety of samples. This report points out the general usefulness of combining different procedures for proteomic analysis, an approach that allows researchers to go deeper in the proteome of samples under investigation.

Proteomics as an innovative tool to investigate frontotemporal disorders.

Neurodegenerative diseases are characterized by slow progressive loss of one or more functions of the CNS. Worldwide, the number of people affected by neurodegeneration is dramatically high and the social impact is upsetting. While being a heterogeneous group of diseases, most of these pathologies manifest similar clinical features and illness progression, thus making their diagnosis elusive. With its ability to meet the needs of neurodegenerative research, proteomics could help facilitate the diagnosis of these disorders. This strategy, recently emerged as complementary to genomics, has led in the last years to substantial achievements in deciphering molecular mechanisms and the follow-up of neurodegenerative diseases. Specifically, aim of this review is to cover the main proteomic investigations realized in the field of familial frontotemporal dementias. This disorder is less common than Alzheimer's disease and disproportionately affects younger individuals, thus representing a major psychological and economic burden for both patients and families. Although early and accurate differential diagnosis of frontotemporal dementias is crucial because of its implications for heritability, prognosis, therapeutics, and environmental management of patients, the investigative methods currently available to clinicians are incomplete. Certainly, the development of a focused therapy cannot be separated from the investigation of biochemical pathways involved in the pathogenesis.

Recent applications of CE- and HPLC-MS in the analysis of human fluids.

The present review intends to cover the literature on the use of CE-/LC-MS for the analysis of human fluids, from 2010 until present. It has been planned to provide an overview of the most recent practical applications of these techniques to less extensively used human body fluids, including, bronchoalveolar lavage fluid, synovial fluid, nipple aspirate, tear fluid, breast fluid, amniotic fluid, and cerumen. Potential pitfalls related to fluid collection and sample preparation, with particular attention to sample clean-up procedures, and methods of analysis, from the research laboratory to a clinical setting will also be addressed. While being apparent that proteomics/metabolomics represent the most prominent approaches for global identification/quantification of putative biomarkers for a variety of human diseases, evidence is also provided of the suitability of these sophisticated techniques for the detection of heterogeneous components carried by these fluids.

Ixodes ricinus and Its Endosymbiont Midichloria mitochondrii: A Comparative Proteomic Analysis of Salivary Glands and Ovaries.

Hard ticks are hematophagous arthropods that act as vectors of numerous pathogenic microorganisms of high relevance in human and veterinary medicine. Ixodes ricinus is one of the most important tick species in Europe, due to its role of vector of pathogenic bacteria such as Borrelia burgdorferi and Anaplasma phagocytophilum, of viruses such as tick borne encephalitis virus and of protozoans as Babesia spp. In addition to these pathogens, I. ricinus harbors a symbiotic bacterium, Midichloria mitochondrii. This is the dominant bacteria associated to I. ricinus, but its biological role is not yet understood. Most M. mitochondrii symbionts are localized in the tick ovaries, and they are transmitted to the progeny. M. mitochondrii bacteria have however also been detected in the salivary glands and saliva of I. ricinus, as well as in the blood of vertebrate hosts of the tick, prompting the hypothesis of an infectious role of this bacterium. To investigate, from a proteomic point of view, the tick I. ricinus and its symbiont, we generated the protein profile of the ovary tissue (OT) and of salivary glands (SG) of adult females of this tick species. To compare the OT and SG profiles, 2-DE profiling followed by LC-MS/MS protein identification were performed. We detected 21 spots showing significant differences in the relative abundance between the OT and SG, ten of which showed 4- to 18-fold increase/decrease in density. This work allowed to establish a method to characterize the proteome of I. ricinus, and to detect multiple proteins that exhibit a differential expression profile in OT and SG. Additionally, we were able to use an immunoproteomic approach to detect a protein from the symbiont. Finally, the method here developed will pave the way for future studies on the proteomics of I. ricinus, with the goals of better understanding the biology of this vector and of its symbiont M. mitochondrii.

Proteomic analysis of lymphoblastoid cells from Nasu-Hakola patients: a step forward in our understanding of this neurodegenerative disorder.

Nasu-Hakola disease (NHD) is a recessively inherited rare disorder characterized by a combination of neuropsychiatric and bone symptoms which, while being unique to this disease, do not provide a rationale for the unambiguous identification of patients. These individuals, in fact, are likely to go unrecognized either because they are considered to be affected by other kinds of dementia or by fibrous dysplasia of bone. Given that dementia in NHD has much in common with Alzheimer's disease and other neurodegenerative disorders, it cannot be expected to achieve the differential diagnosis of this disease without performing a genetic analysis. Under this scenario, the availability of protein biomarkers would indeed provide a novel context to facilitate interpretation of symptoms and to make the precise identification of this disease possible. The work here reported was designed to generate, for the first time, protein profiles of lymphoblastoid cells from NHD patients. Two-dimensional electrophoresis (2-DE) and nano liquid chromatography-tandem mass spectrometry (nLC-MS/MS) have been applied to all components of an Italian family (seven subjects) and to five healthy subjects included as controls. Comparative analyses revealed differences in the expression profile of 21 proteins involved in glucose metabolism and information pathways as well as in stress responses.

Respiratory Proteomics Today: Are Technological Advances for the Identification of Biomarker Signatures Catching up with Their Promise? A Critical Review of the Literature in the Decade 2004-2013.

To improve the knowledge on a variety of severe disorders, research has moved from the analysis of individual proteins to the investigation of all proteins expressed by a tissue/organism. This global proteomic approach could prove very useful: (i) for investigating the biochemical pathways involved in disease; (ii) for generating hypotheses; or (iii) as a tool for the identification of proteins differentially expressed in response to the disease state. Proteomics has not been used yet in the field of respiratory research as extensively as in other fields, only a few reproducible and clinically applicable molecular markers, which can assist in diagnosis, having been currently identified. The continuous advances in both instrumentation and methodology, which enable sensitive and quantitative proteomic analyses in much smaller amounts of biological material than before, will hopefully promote the identification of new candidate biomarkers in this area. The aim of this report is to critically review the application over the decade 2004-2013 of very sophisticated technologies to the study of respiratory disorders. The observed changes in protein expression profiles from tissues/fluids of patients affected by pulmonary disorders opens the route for the identification of novel pathological mediators of these disorders.

An insight into the abundant proteome of 46BR.1G1 fibroblasts deficient of DNA ligase I.

This work presents the proteome profile of cultured human skin fibroblasts established from a patient affected by DNA ligase I (Lig I) deficiency syndrome, a rare disorder characterized by immunodeficiency, growth retardation and sun sensitivity. 2-DE (in the 3-10 and 4-7 pH ranges) was the separation technique used for the production of maps. MALDI-TOF/MS and LC-MS/MS were the mass spectrometry platforms applied for the identification of proteins in gel spots. A total of 154 proteins, including 41 never detected before in skin fibroblasts with this approach, were identified in gel spots analyzed. This newly generated extensive database provides for the first time a global picture of abundant proteins in 46BR.1G1 skin fibroblasts. While being relevant to the particular disorder considered, these results may be regarded as an intriguing starting point on the way to achieve a reference map of the proteins highly expressed in an inherited syndrome with defect in DNA replication and repair pathways.

Phosphorylation of SRSF1 is modulated by replicational stress.

DNA ligase I-deficient 46BR.1G1 cells show a delay in the maturation of replicative intermediates resulting in the accumulation of single- and double-stranded DNA breaks. As a consequence the ataxia telangiectasia mutated protein kinase (ATM) is constitutively phosphorylated at a basal level. Here, we use 46BR.1G1 cells as a model system to study the cell response to chronic replication-dependent DNA damage. Starting from a proteomic approach, we demonstrate that the phosphorylation level of factors controlling constitutive and alternative splicing is affected by the damage elicited by DNA ligase I deficiency. In particular, we show that SRSF1 is hyperphosphorylated in 46BR.1G1 cells compared to control fibroblasts. This hyperphosphorylation can be partially prevented by inhibiting ATM activity with caffeine. Notably, hyperphosphorylation of SRSF1 affects the subnuclear distribution of the protein and the alternative splicing pattern of target genes. We also unveil a modulation of SRSF1 phosphorylation after exposure of MRC-5V1 control fibroblasts to different exogenous sources of DNA damage. Altogether, our observations indicate that a relevant aspect of the cell response to DNA damage involves the post-translational regulation of splicing factor SRSF1 which is associated with a shift in the alternative splicing program of target genes to control cell survival or cell death.

Recent novel MEKC applications to analyze free amino acids in different biomatrices: 2009-2010.

This report intends to provide an updated overview of the most important methodological developments of MEKC in the field of qualitative/quantitative analysis of free amino acids in different matrices. A good number of articles published in the years 2009-2010 addresses the main applications of such procedures together with their advantages and/or drawbacks. The usefulness of chiral CE selective methods for the separation of D-amino acids in biological and food samples and the use of microchips, as well as other foreseen trends in different areas, are also discussed.

Indoleamine 2,3-dioxygenase in lung allograft tolerance.

BACKGROUND: Indoleamine 2,3-dioxygenase (IDO), an enzyme involved in the degradation of tryptophan (Try) to kynurenine (Kyn), is thought to suppress T-cell activity. Although a few experimental studies have suggested a role for IDO in graft acceptance, human data are scarce and inconclusive. We sought to establish whether, in lung transplant recipients (LTRs), plasma IDO activity mirrors the level of graft acceptance. METHODS: We measured the plasma Kyn/Try ratio, reflecting IDO activity, by high-performance liquid chromatography (HPLC) in 90 LTRs, including 26 patients who were still functionally/clinically stable for >36 post-transplant months (stable LTRs) and 64 LTRs with bronchiolitis obliterans syndrome (BOS, Grades 0-p to 3). Twenty-four normal healthy controls (NHCs) were also included. RESULTS: The Kyn/Try ratio in stable LTRs resembled that observed in NHCs, whereas, unexpectedly, patients with BOS, who had lower counts of peripheral CD4(+) T-regulatory cells and tolerogenic plasmacytoid dendritic cells than stable LTRs, showed an increased plasma Kyn/Try ratio compared with both NHCs and stable LTRs. IDO expression by in vitro-stimulated peripheral blood mononuclear cells (PBMC) did not vary between BOS and stable LTRs. Furthermore, BOS patients displayed signs of chronic systemic inflammation (increased plasma levels of interleukin-8 and tumor necrosis factor-alpha) and higher T-cell activation (increased frequency of peripheral interferon-gamma-producing clones). CONCLUSIONS: Our results suggest that, in vivo, in lung transplantation, plasma IDO activity does not reflect the degree of lung graft acceptance, but instead is correlated with the degree of chronic inflammation.

2-DE and LC-MS/MS for a comparative proteomic analysis of BALf from subjects with different subsets of inflammatory myopathies.

The protein profiles of bronchoalveolar lavage fluid (BALf) of patients belonging to three selected subsets of Polymyositis/Dermatomyositis (PM/DM) have been compared by using a combination of 2-DE and MALDI-TOF/MS or LC-MS/MS. Our study examined the hypothesis that there were distinct differences in protein expression profiles that were related to the phenotype. From among the 323+/-51 protein spots that may represent the most highly expressed proteins in BALf of these patients, 24 unique spots were isolated and proteins identified. In particular, 9 spots were present in BALf of PM/DM patients only; 12 spots were exclusive of Overlap patients and 3 spots of AS patients. From among the proteins identified, a few were classified as cytoskeletal proteins, others were involved in oxidative stress and a number of proteins were associated with general metabolic activity or immunological response and inflammation. This is the first study in which evidence is provided that a number of different proteins are expressed in different subsets of PM/DM and supports our contention that the proteomic approach would be beneficial in discovering molecules which could represent possible prognostic factors of these rare pathologies.

Bronchoalveolar lavage fluid proteome in bronchiolitis obliterans syndrome: possible role for surfactant protein A in disease onset.

BACKGROUND: Bronchiolitis obliterans syndrome (BOS) affects long-term survival of lung transplant (Tx) recipients (LTRs), with no consistently effective treatment strategy. Identifying early markers of BOS is of paramount importance for improving graft survival. METHODS: We used 2-dimensional gel electrophoresis and protein identification by mass spectrometry to compare the protein profile of bronchoalveolar lavage fluid (BALf) in two groups of LTRs: one composed of patients with BOS and the other composed of patients with good graft function at >5 years post-surgery (stable LTRs). Based on the hypothesis that only proteins of lung origin could represent reliable BOS markers, we also evaluated paired plasma samples. Proteins of interest were also assessed in the BALf of control subjects and results confirmed by dot- blot analysis. RESULTS: Among 11 differentially expressed proteins, we identified 2 locally produced factors: peroxiredoxin II (PRXII), exclusively expressed in BOS; and surfactant protein A (SP-A), expressed consistently less in BOS patients than in stable LTRs. PRXII expression was never observed in BALf from control subjects, whereas SP-A was present in higher amounts compared with stable LTRs and BOS patients. Finally, the time course of SP-A was studied in 5 LTRs who subsequently developed BOS. A reduction in BALf SP-A content was detectable early after Tx, preceding BOS onset in 4 of 5 patients. CONCLUSIONS: Our results suggest that testing SP-A levels in BALf could predict LTR patients who are at higher risk of BOS development.

2-DE and MALDI-TOF-MS for a comparative analysis of proteins expressed in different cellular models of amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a fatal, neurodegenerative disorder characterized by the selective loss of motor neurons from the spinal cord and brain. About 10% of ALS cases are familial (FALS), and in 20% of these cases the disease has been linked to mutations in the Cu,Zn-SOD1 gene. Although the molecular mechanisms causing these forms of ALS are still unclear, evidence has been provided that motor neurons injuries associated with mutant superoxide dismutase (SOD1)-related FALS result from a toxic gain-in-fuction of the mutated enzyme. To understand better the role of these mutations in the pathophysiology of FALS we have compared the pattern of proteins expressed in human neuroblastoma SH-SY5Y cell line with those of cell lines transfected with plasmids expressing the wild-type human SOD1 and the H46R and G93A mutants. 2-DE coupled to MALDI-TOF-MS were the proteomic tools used for identification of differentially expressed proteins. These included cytoskeletal proteins, proteins that regulate energetic metabolism and intracellular redox conditions, and the ubiquitin proteasome system. The proteomic approach allowed to expand the knowledge on the pattern of proteins, with altered expression, which we should focus on, for a better understanding of the possible mechanism involved in mutated-SOD1 toxicity. The cellular models considered in this work have also evidenced biochemical characteristics common to other SOD1-mutated cellular lines connected to the pathogenesis of ALS.

Optimizing separation efficiency of 2-DE procedures for visualization of different superoxide dismutase forms in a cellular model of amyotrophic lateral sclerosis.

Neurodegenerative diseases such as Alzheimer disease (AD) and Parkinson disease (PD) have been associated with increased production of reactive oxygen species. In AD and PD patients, superoxide dismutase (SOD1) was also indicated as a major target of oxidative damage. In particular, in brain tissue of these patients, different SOD1 isoforms have been identified, although their functional role still remains to be elucidated. In the light of the possibility that different SOD1 entities could be expressed also in other neurodegenerative disorders, as a sort of unifying event with AD and PD, we have investigated amyotrophic lateral sclerosis (ALS) using human neuroblastoma SH-SY5Y cells with mutated SOD1 gene H46R as cellular model. 2-DE using a narrow-range IPG 4-7 strips in the first dimension and linear 15% SDS-PAGE in the second allowed to separate different SOD1 spots. MALDI-TOF MS and CapLC-MS/MS have been used for their complete identification. This is the first report in which the presence of SOD1 (iso) forms in a cellular model of ALS has been evidenced.