Proteomics and its applications for biomarker discovery in human saliva

Human saliva is a biological fluid with enormous diagnostic potential. Because saliva can be non-invasively collected, it provides an attractive alternative for blood, serum or plasma. It has been postulated that the blood concentrations of many components are reflected in saliva. Saliva harbors a wide array of proteins, which can be informative for the detection of diseases. Profiling the proteins in saliva over the course of disease progression could reveal potential biomarkers indicative of different stages of diseases, which may be useful in medical diagnostics. With advanced instrumentation and developed refined analytical techniques, proteomics is widely envisioned as a useful and powerful approach for salivary proteomic biomarker discovery. As proteomic technologies continue to mature, salivary proteomics have great potential for biomarker research and clinical applications. The progress and current status of salivary proteomics and its application in the biomarker discovery of oral and systematic diseases will be reviewed. The scientific and clinical challenges underlying this approach will also be discussed.     

Proteomics and its applications for biomarker discovery in human saliva

Human saliva is a biological fluid with enormous diagnostic potential. Because saliva can be non-invasively collected, it provides an attractive alternative for blood, serum or plasma. It has been postulated that the blood concentrations of many components are reflected in saliva. Saliva harbors a wide array of proteins, which can be informative for the detection of diseases. Profiling the proteins in saliva over the course of disease progression could reveal potential biomarkers indicative of different stages of diseases, which may be useful in medical diagnostics. With advanced instrumentation and developed refined analytical techniques, proteomics is widely envisioned as a useful and powerful approach for salivary proteomic biomarker discovery. As proteomic technologies continue to mature, salivary proteomics have great potential for biomarker research and clinical applications. The progress and current status of salivary proteomics and its application in the biomarker discovery of oral and systematic diseases will be reviewed. The scientific and clinical challenges underlying this approach will also be discussed.     

Usefulness of copeptin as a potential biomarker in TBE

Objective: The aim of the study was to evaluate the usefulness of copeptin for differentiation of hyponatremia in the course of tick-borne encephalitis (TBE) and for being a prognostic marker of the severity of TBE.

Materials and methods: One hundred and fourteen patients with TBE were included in the study. The control group consisted of 62 patients diagnosed with viral meningitis.

Results: Copeptin concentration did not differ in patients with hyponatremia and normonatremia. Urinary sodium excretion to plasma copeptin (copeptin/UNa Secretion) ratio was significantly lower in Syndrome of Inappropriate Antidiuretic Hormone (SIADH) Secretion patients than in patients with hyponatremia of other origin. Mean copeptin concentration in TBE patients was higher than in control group (VM) patients. There were no differences between patients with severe and mild course of TBE.

Conclusions: Copeptin/UNa ratio may be used as a potential biomarker of SIADH in patients with TBE. Copeptin concentration is significantly higher in patients with TBE than in viral meningitis of other origin, especially in patients aged 18–34 and >49 years old. Copeptin does not differentiate TBE of mild and severe course.     

The potential of using blood circular RNA as liquid biopsy biomarker for human diseases

Circular RNA (circRNA) is a novel class of single-stranded RNAs with a closed loop structure. The majority of circRNAs are formed by a back-splicing process in pre-mRNA splicing. Their expression is dynamically regulated and shows spatiotemporal patterns among cell types, tissues and developmental stages. CircRNAs have important biological functions in many physiological processes, and their aberrant expression is implicated in many human diseases. Due to their high stability, circRNAs are becoming promising biomarkers in many human diseases, such as cardiovascular diseases, autoimmune diseases and human cancers. In this review, we focus on the translational potential of using human blood circRNAs as liquid biopsy biomarkers for human diseases. We highlight their abundant expression, essential biological functions and significant correlations to human diseases in various components of peripheral blood, including whole blood, blood cells and extracellular vesicles. In addition, we summarize the current knowledge of blood circRNA biomarkers for disease diagnosis or prognosis.     

Serum lactate as a novel potential biomarker in multiple sclerosis

Multiple sclerosis (MS) is a primary inflammatory demyelinating disease associated with a probably secondary progressive neurodegenerative component. Impaired mitochondrial functioning has been hypothesized to drive neurodegeneration and to cause increased anaerobic metabolism in MS. The aim of our multicentre study was to determine whether MS patients had values of circulating lactate different from those of controls. Patients (n = 613) were recruited, assessed for disability and clinically classified (relapsing–remitting, secondary progressive, primary progressive) at the Catholic University of Rome, Italy (n = 281), at the MS Centre Amsterdam, The Netherlands (n = 158) and at the S. Camillo Forlanini Hospital, Rome, Italy (n = 174). Serum lactate levels were quantified spectrophotometrically with the analyst being blinded to all clinical information. In patients with MS serum lactate was three times higher (3.04 ± 1.26 mmol/l) than that of healthy controls (1.09 ± 0.25 mmol/l, p < 0.0001) and increased across clinical groups, with higher levels in cases with a progressive than with a relapsing–remitting disease course. In addition, there was a linear correlation between serum lactate levels and the expanded disability scale (EDSS) (R² = 0.419; p < 0.001). These data support the hypothesis that mitochondrial dysfunction is an important feature in MS and of particular relevance to the neurodegenerative phase of the disease. Measurement of serum lactate in MS might be a relative inexpensive test for longitudinal monitoring of “virtual hypoxia” in MS and also a secondary outcome for treatment trials aimed to improve mitochondrial function in patients with MS.     

IRF1 as a potential biomarker in Mycobacterium tuberculosis infection

Pulmonary tuberculosis (PTB) is a major global public health problem. The purpose of this study was to find biomarkers that can be used to diagnose tuberculosis. We used four NCBI GEO data sets to conduct analysis. Among the four data sets, GSE139825 is lung tissue microarray, and GSE83456 , GSE19491 and GSE50834 are blood microarray. The differential genes of GSE139825 and GSE83456 were 68 and 226, and intersection genes were 11. Gene ontology (GO) analyses of 11 intersection genes revealed that the changes were mostly enriched in regulation of leucocyte cell-cell adhesion and regulation of T-cell activation. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of DEGs revealed that the host response in TB strongly involves cytokine-cytokine receptor interactions and folate biosynthesis. In order to further narrow the range of biomarkers, we used protein-protein interaction to establish a hub gene network of two data sets and a network of 11 candidate genes. Eventually, IRF1 was selected as a biomarker. As validation, IRF1 levels were shown to be up-regulated in patients with TB relative to healthy controls in data sets GSE19491 and GSE50834 . Additionally, IRF1 levels were measured in the new patient samples using ELISA. IRF1 was seen to be significantly up-regulated in patients with TB compared with healthy controls with an AUC of 0.801. These results collectively indicate that IRF1 could serve as a new biomarker for the diagnosis of pulmonary tuberculosis.     

Total reactive antioxidant potential in human saliva of smokers and non-smokers.

Uric acid is the most important non-enzymatic antioxidant present in human saliva. There is a great variability among individuals, both in salivary uric acid content and saliva total reactive antioxidant potential (TRAP). The uric acid present in saliva correlates with plasma uric acid, suggesting that the former is imported from plasma. There are not statistical differences between uric acid or TRAP values in saliva of smokers and non-smokers. Also, smoking a cigarette does not modify the levels of antioxidants present in saliva.     

Calreticulin as a potential diagnostic biomarker for lung cancer

Calreticulin (CRT) is an endoplasmic reticulum luminal Ca(2+)-binding chaperone protein. By immunizing mice with recombinant fragment (rCRT/39-272), six clones of monoclonal antibodies (mAbs) were generated and characterized. Based on these mAbs, a microplate chemiluminescent enzyme immunoassay (CLEIA) system with a measured limit of detection of 0.09?ng/ml was developed. Using this CLEIA system, it was found that soluble CRT (sCRT) level in serum samples from 58 lung cancer patients was significantly higher than that from 40 healthy individuals (only 9 were detectable, P?相似文献   

Evaluation of the human IgG antibody response to Aedes albopictus saliva as a new specific biomarker of exposure to vector bites

Background

The spread of Aedes albopictus, a vector for re-emergent arbovirus diseases like chikungunya and dengue, points up the need for better control strategies and new tools to evaluate transmission risk. Human antibody (Ab) responses to mosquito salivary proteins could represent a reliable biomarker for evaluating human-vector contact and the efficacy of control programs.

Methodology/Principal Findings

We used ELISA tests to evaluate specific immunoglobulin G (IgG) responses to salivary gland extracts (SGE) in adults exposed to Aedes albopictus in Reunion Island. The percentage of immune responders (88%) and levels of anti-SGE IgG Abs were high in exposed individuals. At an individual level, our results indicate heterogeneity of the exposure to Aedes albopictus bites. In addition, low-level immune cross-reactivity between Aedes albopictus and Aedes aegypti SGEs was observed, mainly in the highest responders.

Conclusion/Significance

Ab responses to saliva could be used as an immuno-epidemiological tool for evaluating exposure to Aedes albopictus bites. Combined with entomological and epidemiological methods, a “salivary” biomarker of exposure to Aedes albopictus could enhance surveillance of its spread and the risk of arbovirus transmission, and could be used as a direct tool for the evaluation of Aedes albopictus control strategies.     

MiRNAs as potential biomarker of kidney diseases: A review

MicroRNAs (miRNAs) are 22 nucleotides short, non-coding and tissue-specific single-stranded RNA which modulates target gene expression. Presently, shreds of evidence confirmed that miRNAs play a key role in kidney pathophysiology. The objectives of the present review are to summarize new research data towards the latest developments in the potential use of miRNAs as a diagnostic biomarker for kidney diseases. This holistic information will update the existing knowledge of kidney disease biomarkers. “miRNA profile for Diabetic Kidney disease, Acute kidney injury, Renal fibrosis, hemodialysis, transplants, FSGS, IgAN, etc.” are the search keywords which have been used in this review. The search outcome gave an exciting insightful perception of miRNAs competence as a biomarker. Also it is observed that various samples as plasma, urine and biopsies were used for profiling the miRNA expression. The miRNAs were not only used for diagnostic biomarkers but also for therapeutic targets. Each kidney disease showed different miRNAs expression profile and few miRNAs quite common with some kidney diseases. miRNAs are simple and efficient diagnostic biomarkers for kidney diseases.     

Interferon-gamma inducible protein-10 as a potential biomarker in localized scleroderma

Introduction

The purpose of this study was to evaluate the presence and levels of interferon-gamma inducible protein-10 (IP-10) in the plasma and skin of pediatric localized scleroderma (LS) patients compared to those of healthy pediatric controls and to determine if IP-10 levels correlate to clinical disease activity measures.

Methods

The presence of IP-10 in the plasma was analyzed using a Luminex panel in 69 pediatric patients with LS and compared to 71 healthy pediatric controls. Of these patients, five had available skin biopsy specimens with concurrent clinical and serological data during the active disease phase, which were used to analyze the presence and location of IP-10 in the skin by immunohistochemistry (IHC).

Results

IP-10 levels were significantly elevated in the plasma of LS patients compared to that of healthy controls and correlated to clinical disease activity measures in LS. Immunohistochemistry staining of IP-10 was present in the dermal infiltrate of LS patients and was similar to that found in psoriasis skin specimens, the positive disease control.

Conclusions

Elevation of IP-10 levels in the plasma compared to those of healthy controls and the presence of IP-10 staining in the affected skin of LS patients indicates that IP-10 is a potential biomarker in LS. Furthermore, significant elevation of IP-10 in LS patients with active versus inactive disease and correlations between IP-10 levels and standardized disease outcome measures of activity in LS strongly suggest that IP-10 may be a biomarker for disease activity in LS.     

Liquid biopsy: miRNA as a potential biomarker in oral cancer

Oral cancer is one of the leading cancers in South-Asian countries. Despite the easy access of the oral cavity, the detection and five year survival rates of OSCC patients are dismal. Identification of non-invasive biomarkers to determine the progression and recurrence of OSCC could be of immense help to patients. Recent studies on oral cancer suggest the importance of non-invasive biomarker development. Micro-RNAs (miRNAs) are one of the important components of the cell-free nucleic acids available in different body fluids. Here, we have reviewed the current understanding of circulating miRNAs as non-invasive biomarkers in different body fluids of oral cancer patients. A number of circulating miRNAs are found to be common in the body fluids of OSCC patients, while many of these are study specific, the possible sources of this variability could be due to differences in sample processing, assay procedure, clinical stage of the disease, oral habit and environmental factors. The prognostic and therapeutic significance of these circulating miRNAs are suggested by several studies. Mir-371, mir-150, mir-21 and mir-7d were found to be potential prognostic markers, while mir-134, mir-146a, mir-338 and mir-371 were associated with metastases. The prognostic markers, mir-21 and mir-7d were also found to be significantly correlated with resistance to chemotherapy, while mir-375, mir-196 and mir-125b were significantly correlated with sensitivity to radiotherapy. Despite the promising roles of circulating miRNAs, challenges still remain in unravelling the exact regulation of these miRNAs before using them for targeted therapy.     

Regucalcin as a potential biomarker for metabolic and neuronal diseases

Regucalcin was initially discovered in 1978 as a regulatory protein in calcium signaling. The regucalcin gene, which is localized on the X chromosome, is found in vertebrate and invertebrate species. Regucalcin has been shown to play a pivotal role in cell regulation: maintaining of intracellular calcium homeostasis, suppressions of signal transduction, inhibition of translational protein synthesis, nuclear deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) synthesis, regulation of gene expression, and anti-effects on proliferation and apoptosis in many cell types. The expression of the regucalcin gene and its protein has been shown to alter with various metabolic diseases, and regucalcin plays an important role in the development of many pathophysiologic states. Serum regucalcin has been found to increase with liver injury, and also urinary regucalcin is elevated with kidney damage, suggesting a useful tool as biomarker for diagnosis. Moreover, regucalcin has been shown to be good tool in early diagnosis for Alzheimer’s disease and other brain diseases. This review will discuss a significance of regucalcin as a clinical biomarker in various diseases.     

Suction blister fluid as potential body fluid for biomarker proteins

Early diagnosis is important for effective disease management. Measurement of biomarkers present at the local level of the skin could be advantageous in facilitating the diagnostic process. The analysis of the proteome of suction blister fluid, representative for the interstitial fluid of the skin, is therefore a desirable first step in the search for potential biomarkers involved in biological pathways of particular diseases. Here, we describe a global analysis of the suction blister fluid proteome as potential body fluid for biomarker proteins. The suction blister fluid proteome was compared with a serum proteome analyzed using identical protocols. By using stringent criteria allowing less than 1% false positive identifications, we were able to detect, using identical experimental conditions and amount of starting material, 401 proteins in suction blister fluid and 240 proteins in serum. As a major result of our analysis we construct a prejudiced list of 34 proteins, relatively highly and uniquely detected in suction blister fluid as compared to serum, with established and putative characteristics as biomarkers. We conclude that suction blister fluid might potentially serve as a good alternative biomarker body fluid for diseases that involve the skin.     

Label-free, chemiresistor immunosensor for stress biomarker cortisol in saliva

Salivary cortisol is commonly used as a bioindicator of the psychobiologic response to environmental and psychological stressors. Current analytical approaches rely on immunoassays performed at distant, centralized laboratories and involve an elaborate specimen collection-processing-transportation-storage-analysis-reporting cycle. To facilitate point-of-use measurement of salivary cortisol levels, we describe the development and proof-of-concept testing of an ultrasensitive, label-free immunosensor based on a single-walled, carbon nanotube-based chemiresistive transducer. Carbon nanotubes were functionalized with a cortisol analog [cortisol-3-CMO-NHS ester] and a monoclonal anti-cortisol antibody was ligated to this receptor. Addition of phosphate buffer as well as artificial saliva spiked with varying cortisol concentrations displaced the anti-cortisol antibody producing corresponding decreases in the resistance/conductance of the nanotube-biomolecule hybrid. The immunosensor demonstrated an ultralow detection limit of 1 pg/ml and excellent binding selectivity for cortisol even in the presence of structurally similar steroids such as 21-hydroprogesterone. The nanotube immunosensor offers attractive prospects for the development of highly sensitive biosensor for rapid, label-free measurement of salivary cortisol in a variety of clinical and research settings.     

Endocannabinoids effect on oxidative status of human platelets

Reactive oxygen species (ROS) are known to regulate platelet activation. Since endocannabinoids behave as platelet agonists, we investigated the effect of two endocannabinoids, 2-arachidonoylglycerol (2AG) and anandamide (AEA) on the oxidative status of human platelets. We have demonstrated that 2AG and AEA stimulate ROS production, superoxide anion formation and lipid peroxidation. The effect is dose and time dependent and mainly occurs through the involvement of cannabinoid receptor 1 (CB1) since all tested parameters are greatly reduced by SR141716, the CB1 specific inhibitor. The specific inhibitor of cannabinoid receptor 2 (CB2) SR144528 produces a very small inhibition. The involvement of syk/PI3K/AKT/mTor pathway in oxidative stress induced by endocannabinoids is shown. Nicotinamide adenine dinucleotide phosphate oxidase seems to be poorly involved in the endocannabinoids effect. Concerning the aerobic metabolism, it has been demonstrated that endocannabinoids reduce the oxygen consumption and adenosine triphosphate synthesis, both in the presence of pyruvate + malate or succinate. In addition, endocannabinoids inhibit the activity of respiratory complexes II, III and IV and increase the activity of respiratory complex I. The endocannabinoids effect on aerobic metabolism seems to be also a CB1 mediated mechanism. Thus, in human platelets oxidative stress induced by endocannabinoids, mainly generated in the respiratory chain through the activation of complex I and the inhibition of complex II, III and IV, may lead to thrombotic events, contributing to cardiovascular diseases.