Sputum and salivary protein biomarkers and point-of-care biosensors for the management of COPD

Biological and technical factors affecting the point-of-care diagnostics in not-oncological chronic diseases

Inexpensive point-of-care (POC) analytical solutions have the potential to allow the implementation of large-scale screening campaigns aimed at identifying the initial stages of pathologies in the population, reducing morbidity, mortality and, indirectly, also the costs for the healthcare system. At global level, the most common preventive screening schemes address some cancer pathologies or are used to monitor the spread of some infective diseases. However, systematic testing might become decisive to improve the care response even in the case of chronic pathologies and, in this review, we analyzed the state-of-the-art of the POC diagnostics for Chronic Kidney Disease, Chronic Obstructive Pulmonary Disease and Multiple Sclerosis. The different technological options used to manufacture the biosensors and evaluate the produced data have been described and this information has been integrated with the present knowledge relatively to the biomarkers that have been proposed to monitor such diseases, namely their availability and reliability. Finally, the nature of the macromolecules used to capture the biomarkers has been discussed in relation to the biomarker nature.

Innovations in Biosensor Technologies for Healthcare Diagnostics and Therapeutic Drug Monitoring: Applications, Recent Progress, and Future Research Challenges

This comprehensive review delves into the forefront of biosensor technologies and their critical roles in disease biomarker detection and therapeutic drug monitoring. It provides an in-depth analysis of various biosensor types and applications, including enzymatic sensors, immunosensors, and DNA sensors, elucidating their mechanisms and specific healthcare applications. The review highlights recent innovations such as integrating nanotechnology, developing wearable devices, and trends in miniaturisation, showcasing their transformative potential in healthcare. In addition, it addresses significant sensitivity, specificity, reproducibility, and data security challenges, proposing strategic solutions to overcome these obstacles. It is envisaged that it will inform strategic decision-making, drive technological innovation, and enhance global healthcare outcomes by synthesising multidisciplinary insights.

Mucus Structure, Viscoelastic Properties, and Composition in Chronic Respiratory Diseases

The respiratory mucus, a viscoelastic gel, effectuates a primary line of the airway defense when operated by the mucociliary clearance. In chronic respiratory diseases (CRDs), such as asthma, chronic obstructive pulmonary disease (COPD), and cystic fibrosis (CF), the mucus is overproduced and its solid content augments, changing its structure and viscoelastic properties and determining a derangement of essential defense mechanisms against opportunistic microbial (virus and bacteria) pathogens. This ensues in damaging of the airways, leading to a vicious cycle of obstruction and infection responsible for the harsh clinical evolution of these CRDs. Here, we review the essential features of normal and pathological mucus (i.e., sputum in CF, COPD, and asthma), i.e., mucin content, structure (mesh size), micro/macro-rheology, pH, and osmotic pressure, ending with the awareness that sputum biomarkers (mucins, inflammatory proteins and peptides, and metabolites) might serve to indicate acute exacerbation and response to therapies. There are some indications that old and novel treatments may change the structure, viscoelastic properties, and biomarker content of sputum; however, a wealth of work is still needed to embrace these measures as correlates of disease severity in association with (or even as substitutes of) pulmonary functional tests.

Role and new insights of microfibrillar-associated protein 4 in fibrotic diseases

Fibrosis is one of the most worrisome complications of chronic inflammatory diseases, leading to tissue damage, organ failure, and ultimately, death. The most notable pathological characteristic of fibrosis is the excessive accumulation of extracellular matrix (ECM) components such as collagen and fibronectin adjacent to foci of inflammation or damage. The human microfibrillar-associated protein 4 (MFAP4), an important member of the superfamily of fibrinogen-related proteins, is considered to have an extremely important role in ECM transformation of fibrogenesis. This review summarizes the structure, characteristics, and physiological functions of MFAP4 and the importance of MFAP4 in various fibrotic diseases. Meanwhile, we elaborated the underlying actions and mechanisms of MFAP4 in the development of fibrosis, suggesting that a better understand of MFAP4 broadens novel perspective for early screening, diagnosis, prognostic risk assessment, and treatment of fibrotic diseases.

The salivary microbiota of patients with acute lower respiratory tract infection-A multicenter cohort study

The human microbiome contributes to health and disease, but the oral microbiota is understudied relative to the gut microbiota. The salivary microbiota is easily accessible, underexplored, and may provide insight into response to infections. We sought to determine the composition, association with clinical features, and heterogeneity of the salivary microbiota in patients with acute lower respiratory tract infection (LRTI). We conducted a multicenter prospective cohort study of 147 adults with acute LRTI presenting to the emergency department of seven hospitals in three states (Pennsylvania, Michigan, and Ohio) between May 2017 and November 2018. Salivary samples were collected in the emergency department, at days 2-5 if hospitalized, and at day 30, as well as fecal samples if patients were willing. We compared salivary microbiota profiles from patients to those of healthy adult volunteers by sequencing and analyzing bacterial 16-rRNA. Compared to healthy volunteers, the salivary microbiota of patients with LRTI was highly distinct and strongly enriched with intestinal anaerobes such as Bacteroidaceae, Ruminococcaceae, and Lachnospiraceae (e.g., mean 10% relative abundance of Bacteroides vs < 1% in healthy volunteers). Within the LRTI population, COPD exacerbation was associated with altered salivary microbiota composition compared to other LRTI conditions. The largest determinant of microbiota variation within the LRTI population was geography (city in which the hospital was located).

Facemask analyses for the non-invasive detection of chronic and acute P. aeruginosa lung infections using nanoparticle-based immunoassays

Pseudomonas aeruginosa (P. aeruginosa) is a pathogen that persistently colonizes the respiratory tract of patients with chronic lung diseases. The risk of acquiring a chronic P. aeruginosa infection can be minimized by rapidly detecting the pathogen in the patient's airways and promptly administrating adequate antibiotics. However, the rapid detection of P. aeruginosa in the lungs involves the analysis of sputum, which is a highly complex matrix that is not always available. Here, we propose an alternative diagnosis based on analyzing breath aerosols. In this approach, nanoparticle immunosensors identify bacteria adhered to the polypropylene layer of a surgical facemask that was previously worn by the patient. A polypropylene processing protocol was optimized to ensure the efficient capture and analysis of the target pathogen. The proposed analytical platform has a theoretical limit of detection of 105 CFU mL-1 in aerosolized mock samples, and a dynamic range between 105 and 108 CFU mL-1. When tested with facemasks worn by patients, the biosensors were able to detect chronic and acute P. aeruginosa lung infections, and to differentiate them from respiratory infections caused by other pathogens. The results shown here pave the way to diagnose Pseudomonas infections at the bedside, as well as to identify the progress from chronic to acute infection.

Engineering a Point-of-Care Paper-Microfluidic Electrochemical Device Applied to the Multiplexed Quantitative Detection of Biomarkers in Sputum

Health initiatives worldwide demand affordable point-of-care devices to aid in the reduction of morbidity and mortality rates of high-incidence infectious and noncommunicable diseases. However, the production of robust and reliable easy-to-use diagnostic platforms showing the ability to quantitatively measure several biomarkers in physiological fluids and that could in turn be decentralized to reach any relevant environment remains a challenge. Here, we show the particular combination of paper-microfluidic technology, electrochemical transduction, and magnetic nanoparticle-based immunoassay approaches to produce a unique, compact, and easily deployable multiplex device to simultaneously measure interleukin-8, tumor necrosis factor-α, and myeloperoxidase biomarkers in sputum, developed with the aim of facilitating the timely detection of acute exacerbations of chronic obstructive pulmonary disease. The device incorporates an on-chip electrochemical cell array and a multichannel paper component, engineered to be easily aligned into a polymeric cartridge and exchanged if necessary. Calibration curves at clinically relevant biomarker concentration ranges are produced in buffer and artificial sputum. The analysis of sputum samples of healthy individuals and acutely exacerbated patients produces statistically significant biomarker concentration differences between the two studied groups. The device can be mass-produced at a low cost, being an easily adaptable platform for measuring other disease-related target biomarkers.

Prognostic Biomarkers Based on Proteomic Technology in COPD: A Recent Review

Chronic obstructive pulmonary disease (COPD) is a common heterogeneous respiratory disease which is characterized by persistent and incompletely reversible airflow limitation. Due to the heterogeneity and phenotypic complexity of COPD, traditional diagnostic methods provide limited information and pose a great challenge to clinical management. In recent years, with the development of omics technologies, proteomics, metabolomics, transcriptomics, etc., have been widely used in the study of COPD, providing great help to discover new biomarkers and elucidate the complex mechanisms of COPD. In this review, we summarize the prognostic biomarkers of COPD based on proteomic studies in recent years and evaluate their association with COPD prognosis. Finally, we present the prospects and challenges of COPD prognostic-related studies. This review is expected to provide cutting-edge evidence in prognostic evaluation of clinical patients with COPD and to inform future proteomic studies on prognostic biomarkers of COPD.

Virtual monitoring in CF - the importance of continuous monitoring in a multi-organ chronic condition

Cystic Fibrosis (CF) is a chronic life-limiting condition that affects multiple organs within the body. Patients must adhere to strict medication regimens, physiotherapy, diet, and attend regular clinic appointments to manage their condition effectively. This necessary but burdensome requirement has prompted investigations into how different digital health technologies can enhance current care by providing the opportunity to virtually monitor patients. This review explores how virtual monitoring has been harnessed for assessment or performance of physiotherapy/exercise, diet/nutrition, symptom monitoring, medication adherence, and wellbeing/mental-health in people with CF. This review will also briefly discuss the potential future of CF virtual monitoring and some common barriers to its current adoption and implementation within CF. Due to the multifaceted nature of CF, it is anticipated that this review will be relevant to not only the CF community, but also those investigating and developing digital health solutions for the management of other chronic diseases.

Advances in Electrochemical Biosensors Based on Nanomaterials for Protein Biomarker Detection in Saliva

The focus on precise medicine enhances the need for timely diagnosis and frequent monitoring of chronic diseases. Moreover, the recent pandemic of severe acute respiratory syndrome coronavirus 2 poses a great demand for rapid detection and surveillance of viral infections. The detection of protein biomarkers and antigens in the saliva allows rapid identification of diseases or disease changes in scenarios where and when the test response at the point of care is mandated. While traditional methods of protein testing fail to provide the desired fast results, electrochemical biosensors based on nanomaterials hold perfect characteristics for the detection of biomarkers in point-of-care settings. The recent advances in electrochemical sensors for salivary protein detection are critically reviewed in this work, with emphasis on the role of nanomaterials to boost the biosensor analytical performance and increase the reliability of the test in human saliva samples. Furthermore, this work identifies the critical factors for further modernization of the nanomaterial-based electrochemical sensors, envisaging the development and implementation of next-generation sample-in-answer-out systems.

A Systematic Review of Internet of Things in Clinical Laboratories: Opportunities, Advantages, and Challenges

The Internet of Things (IoT) is the network of physical objects embedded with sensors, software, electronics, and online connectivity systems. This study explores the role of IoT in clinical laboratory processes; this systematic review was conducted adhering to the PRISMA Statement 2020 guidelines. We included IoT models and applications across preanalytical, analytical, and postanalytical laboratory processes. PubMed, Cochrane Central, CINAHL Plus, Scopus, IEEE, and A.C.M. Digital library were searched between August 2015 to August 2022; the data were tabulated. Cohen's coefficient of agreement was calculated to quantify inter-reviewer agreements; a total of 18 studies were included with Cohen's coefficient computed to be 0.91. The included studies were divided into three classifications based on availability, including preanalytical, analytical, and postanalytical. The majority (77.8%) of the studies were real-tested. Communication-based approaches were the most common (83.3%), followed by application-based approaches (44.4%) and sensor-based approaches (33.3%) among the included studies. Open issues and challenges across the included studies included scalability, costs and energy consumption, interoperability, privacy and security, and performance issues. In this study, we identified, classified, and evaluated IoT applicability in clinical laboratory systems. This study presents pertinent findings for IoT development across clinical laboratory systems, for which it is essential that more rigorous and efficient testing and studies be conducted in the future.

Novel Applications of Biomarkers in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is an important health problem and an increasing cause of morbidity and mortality worldwide. Currently, COPD is considered a multisystem disease. Although it primarily affects the lungs, structural and functional changes occur in other organs due to systemic inflammation. It is stated that in patients with COPD, airway and systemic inflammatory markers are increased and that these markers are high are associated with a faster decline in lung functions. In recent years, numerous articles have been published on the discovery and evaluation of biomarkers in COPD. Many markers have also been studied to accurately assess COPD exacerbations and provide effective treatment. However, based on the evidence from published studies, a single molecule has not been adequately validated for broad clinical use.

Proteomic Analysis of Human Sputum for the Diagnosis of Lung Disorders: Where Are We Today?

The identification of markers of inflammatory activity at the early stages of pulmonary diseases which share common characteristics that prevent their clear differentiation is of great significance to avoid misdiagnosis, and to understand the intrinsic molecular mechanism of the disorder. The combination of electrophoretic/chromatographic methods with mass spectrometry is currently a promising approach for the identification of candidate biomarkers of a disease. Since the fluid phase of sputum is a rich source of proteins which could provide an early diagnosis of specific lung disorders, it is frequently used in these studies. This report focuses on the state-of-the-art of the application, over the last ten years (2011-2021), of sputum proteomics in the investigation of severe lung disorders such as COPD; asthma; cystic fibrosis; lung cancer and those caused by COVID-19 infection. Analysis of the complete set of proteins found in sputum of patients affected by these disorders has allowed the identification of proteins whose levels change in response to the organism's condition. Understanding proteome dynamism may help in associating these proteins with alterations in the physiology or progression of diseases investigated.

Lack of Evidence for a Relationship Between Salivary CRP and Women's Sexual Desire: An Investigation Across Clinical and Healthy Samples

BACKGROUND

Inflammation has been linked to a variety of mental and physical health outcomes that disproportionately impact women, and which can impair sexual function; thus, there is reason to expect a link between inflammation and women's sexual functioning.

AIM

To test the hypothesis that higher concentrations of C-reactive protein (CRP), a general biomarker of inflammation, would predict women's lower sexual desire.

METHOD

As 2 independent research teams, we conducted 3 separate studies (total n = 405) that assessed salivary CRP and various measurements of sexual desire in different women populations.

OUTCOMES

Female Sexual Function Index, Sexual Desire Inventory-2, Decreased Sexual Desire Screener, and Sexual Interest and Desire Inventory.

RESULTS

Regardless of the way sexual desire was measured (e.g., state vs trait; general desire vs. desire functioning) and the population sampled (i.e., healthy vs. clinically diagnosed with sexual dysfunction), all the studies revealed null results.

CLINICAL IMPLICATIONS

While exploratory, the convergence of these null results across studies and researchers suggests that if there is an association between inflammation and women's sexual desire, it is likely very subtle.

STRENGTHS & LIMITATIONS

Across 2 independent research teams, 3 unrelated studies, and various measurements of sexual desire, results were consistent. These points lend to the generalizability of the results. However, study designs were cross-sectional.

CONCLUSIONS

Future research may reveal (i) a non-linear threshold effect, such that inflammation does not begin to impact women's sexual desire until it is at a high level, (ii) inflammatory biomarkers other than CRP might be more sensitive in detecting associations between inflammation and desire, should they exist, or (iii) the mechanisms underlying sexual dysfunction may differ between sexes. Clephane K, et al. Lack of Evidence for a Relationship Between Salivary CRP and Women's Sexual Desire: An Investigation Across Clinical and Healthy Samples. J Sex Med 2022;19:745-760.

Defining the Protease and Protease Inhibitor (P/PI) Proteomes of Healthy and Diseased Human Skin by Modified Systematic Review

Proteases and protease inhibitors (P/PIs) are involved in many biological processes in human skin, yet often only specific families or related groups of P/PIs are investigated. Proteomics approaches, such as mass spectrometry, can define proteome signatures (including P/PIs) in tissues; however, they struggle to detect low-abundance proteins. To overcome these issues, we aimed to produce a comprehensive proteome of all P/PIs present in normal and diseased human skin, in vivo, by carrying out a modified systematic review using a list of P/PIs from MEROPS and combining this with key search terms in Web of Science. Resulting articles were manually reviewed against inclusion/exclusion criteria and a dataset constructed. This study identified 111 proteases and 77 protease inhibitors in human skin, comprising the serine, metallo-, cysteine and aspartic acid catalytic families of proteases. P/PIs showing no evidence of catalytic activity or protease inhibition, were designated non-peptidase homologs (NPH), and no reported protease inhibitory activity (NRPIA), respectively. MMP9 and TIMP1 were the most frequently published P/PIs and were reported in normal skin and most skin disease groups. Normal skin and diseased skin showed significant overlap with respect to P/PI profile; however, MMP23 was identified in several skin disease groups, but was absent in normal skin. The catalytic profile of P/PIs in wounds, scars and solar elastosis was distinct from normal skin, suggesting that a different group of P/PIs is responsible for disease progression. In conclusion, this study uses a novel approach to provide a comprehensive inventory of P/PIs in normal and diseased human skin reported in our database. The database may be used to determine either which P/PIs are present in specific diseases or which diseases individual P/PIs may influence.

Role and mechanism of miR-181a-5p in mice with chronic obstructive pulmonary disease by regulating HMGB1 and the NF-κB pathway

Chronic obstructive pulmonary disease (COPD) is a common respiratory disease. This study explored the mechanism of miR-181a-5p in the inflammatory response in COPD mice. COPD mouse models were established by cigarette smoke (CS) exposure following pretreatment with recombinant adeno-associated virus (rAAv)-miR-181a-5p, si-HMGB1 (high mobility group box 1), and NF-κB pathway inhibitor PDTC, respectively. Pathological changes of lung tissues were determined by HE staining. BALF was collected to count total cells, neutrophils and lymphocytes using a Countess II automatic cell counter. Expressions of NE and inflammatory factors (TNF-α, IL-6, IL-8 and IFN-γ) were detected by ELISA. Binding relationship between miR-181a-5p and HMGB1 was predicted on Starbase (http://starbase.sysu.edu.cn/index.php) and validated by dual-luciferase assay. miR-181a-5p expression was detected by RT-qPCR, and expressions of HMGB1, IκBα, p-IκBα were detected by Western blot. The expression level of miR-181a-5p was lower in lung tissues. miR-181a-5p overexpression alleviated inflammatory response and pathological changes of lung tissues in COPD mice, with decreased pulmonary inflammation scores, total cells, neutrophils, and lymphocytes and expressions of NE and inflammatory factors. HMGB1 expression level was increased in COPD mice. miR-181a-5p targeted HMGB1. si-HMGB1 relieved inflammatory responses in COPD mice. NF-κB was activated in COPD mice, evidenced by degraded IκBα and increased p-IκBα level. si-HMGB1 significantly restrained the activation of NF-κB pathway. Briefly, miR-181a-5p targets HMGB1 to inhibit the NF-κB pathway, thus alleviating the inflammatory response in COPD mice.

Effect of physical training on cytokine expression in CD4+ T lymphocytes in subjects with stable COPD

Introduction:

Although evidence suggests that physical exercise reduces systemic inflammation, at the plasma level, there are still contradictions in chronic obstructive pulmonary disease (COPD). In this sense, analysis of intracellular cytokines could clear off the effect of physical exercise on the inflammatory profile of these subjects.

Aim:

The aim was to evaluate the effect of physical training on cytokine expression in CD4+ T lymphocytes from subjects with COPD.

Methods:

This is a randomized controlled trial. Subjects with stable COPD were grouped into two groups, exercise and control. In total, 23 subjects with stable COPD were evaluated, of which 15 underwent aerobic strength training [physical exercise group (PEG)] and 8 underwent breathing exercises [respiratory physiotherapy group (RPG)]. Intracellular cytokines [interleukin (IL)-8, IL-13, IL-17, IL-6, IL-2, IL-10, and tumor necrosis factor alpha (TNF-α)] from CD4+ T lymphocytes were analyzed from peripheral blood through flow cytometry, before and after 8 weeks of intervention.

Results:

The PEG and RPG groups had a mean age of 68 ± 5.96 and 72.25 ± 6.86 years and predicted forced expiratory volume in the first second (FEV₁) of 58.6 ± 15.99% and 39.75 ± 10.39%, respectively. It was possible to detect a significant reduction in IL-8 (p = 0.0125) and an increase in IL-13 (p = 0.0014) and an increase in TNF-α (p < 0.001) in both groups.

Conclusion:

Eight weeks of physical training, both peripheral and respiratory, were able to reduce concentrations of IL-8 and to increase IL-13, and TNF-α in CD4+ T lymphocytes in subjects with stable COPD. The findings reinforce the benefits of interventions in subjects with COPD, revealing data not previously investigated.

Cascade of immune mechanism and consequences of inflammatory disorders

Inflammatory responses arise as an outcome of tissues or organs exposure towards harmful stimuli like injury, toxic chemicals or pathogenic microorganism. It is a complex cascade of immune mechanism to overcome from tissue injury and to initiate the healing process by recruiting various immune cells, chemical mediators such as the vasoactive peptides and amines, pro-inflammatory cytokines, eicosanoids and acute-phase proteins to prevent tissue damage and ultimately complete restoration of the tissue function. The cytokines exhibits a central function in communication between the cells, inflammatory response initiation, amplification and their regulation. This review covers the importance of inflammatory responses; the significance of cytokines in inflammation and numerous inflammatory disorders/ailments due to the abrupt expression of cytokines and the hyper-inflammatory response or cytokine storm associated with poor prognosis in COVID-19 pandemic. Also highlighting the importance of naturally derived anti-inflammatory metabolites to overcome the side-effects of currently prevailing anti-inflammatory drugs.

Kakkonto Inhibits Cytokine Production Induced by Rhinovirus Infection in Primary Cultures of Human Nasal Epithelial Cells

Rhinovirus (RV) is a primary etiologic agent of common cold that can subsequently acutely exacerbate bronchial asthma or chronic obstructive pulmonary disease. Kakkonto (Ge-gen-tang in Chinese), one of the most frequently prescribed traditional Japanese (Kampo) medicines, is used for treating common cold, shoulder stiffness, or inflammatory diseases of the upper body. Previous experimental studies have indicated that kakkonto exerts antiviral and anti-inflammatory effects on the influenza virus and the human respiratory syncytial virus. However, there is a lack of reports investigating the efficacy of kakkonto in RV infection. Hence, the aim of the current study was to investigate the effects of kakkonto on RV infection of human nasal epithelial (HNE) cells. HNE cells obtained via endoscopic sinus surgery were cultured and infected with RV14, with or without kakkonto treatment. The supernatants from the cells were collected, and the RV14 titer and cytokine levels were assessed. Reverse transcription-polymerase chain reaction was performed to determine the amount of viral RNA, while the level of nuclear factor kappa B (NF-κB) subunits in the nucleus was assessed by enzyme-linked immunosorbent assay. Although kakkonto treatment did not reduce RV14 titer or RNA levels, indicating that it did not inhibit RV14 proliferation, it was found to reduce the production of specific pro-inflammatory cytokines, including interleukin (IL)-8, tumor necrosis factor (TNF)-α, and monocyte chemotactic protein-1 (MCP-1). Unlike that observed with the kakkonto extract, none of the crude drugs contained in kakkonto reduced IL-8 level. Furthermore, though kakkonto treatment significantly reduced p50 levels, it did not impact the p65 subunit of NF-κB. These results indicated that kakkonto can inhibit inflammation caused by RV infection and may exert an immunomodulatory effect on HNE cells. This is the first report to elucidate the effects of kakkonto extract on RV infection in primary cultures of HNE cells, providing evidence that kakkonto may act as an effective therapy for RV infection and subsequent airway inflammation.

A narrative review of exploring potential salivary biomarkers in respiratory diseases: still on its way

Saliva is abundant with proteins, metabolites, DNA, and a diverse range of bacterial species. During the past two decades, saliva has emerged as a novel diagnostic and evaluation medium for several diseases. Collection of saliva samples is simple, minimally invasive, and convenient even in infants, children, and patients with anxious. Furthermore, with the development of hypersensitive techniques [e.g., microsensor arrays, enzyme-labeled immunosensors, nanoparticle-labeled immunosensors, capacitive or impedimetric immunosensors, magneto immunosensors, field effect transistor immunosensors, and surface enhanced Raman spectroscopy (SERS)], the sensitivity and accuracy of saliva diagnostic procedures have been improved. Nowadays, saliva has been used as a potential medium for several disease diagnosis and assessment, such as periodontitis, caries, cancers, diabetes mellitus, and cardiovascular diseases. Saliva has been used widely for studying microbiomics, genomics, transcriptomics, proteomics, and metabolomics of respiratory diseases, however, the use of salivary biomarkers for the diagnosis, prognosis, and monitoring of respiratory disease is still in its infancy. Herein, we review the progress of research on salivary biomarkers related to several respiratory diseases, including bronchial asthma, chronic obstructive pulmonary disease (COPD), obstructive sleep apnea (OSA), pneumonia, tuberculosis (TB), Langerhans cell histiocytosis (LCH) and cystic fibrosis (CF). Furthermore, several limitations of saliva test such as the lack of standard protocol for saliva collection and reasonable reference values for saliva test are also mentioned in this review.

Silencing YKL-40 gene can inhibit inflammatory factor expression and affects the effect of THP-1 cells on endometrial cancer

PURPOSE

To investigate the effect of silencing the YKL-40 gene on the expression of inflammatory factors and the effect of silencing the YKL-40 gene of THP-1 cells on endometrial cancer.

METHODS

We used a siRNA targeting a sequence in YKL-40 (si-YKL-40) to transfect HEC-1A and THP-1 cells. Quantitative real-time polymerase chain reaction assay was performed to investigate the mRNA levels of YKL-40, IL-8 and MMP-9 in HEC-1A and THP-1 cells. Migration, and invasion assays were performed to identify the effects of co-culture with THP-1 cells that silenced YKL-40 gene on the migration and invasion capacity of HEC-1A cells. Tube formation ability were detected by Matrigel-based angiogenesis assay.

RESULTS

We successfully transfected HEC-1A and THP-1 cells with lentivirus to silence the YKL-40 gene. Compared with the blank control group and NC group, the expression of YKL-40, IL-8 and MMP-9 which were examined by qRT-PCR in YKL-40-siRNA group was significantly reduced in the two cell lines; after co-cultured with the supernatant of transfected THP-1 cells, the migration and invasion ability of HEC-1A cells in YKL-40-siRNA group was significantly reduced; the number of tubes in the YKL-40-siRNA group was significantly reduced, the spacing between the tubes was significantly increased, and the structure of tubes was incomplete.

CONCLUSION

Silencing the YKL-40 gene in THP-1 cells can inhibit the expression of inflammatory factors, the invasion and migration of human endometrial cancer cells and the capacity of vitro angiogenic. And YKL-40 gene as a marker of inflammation may be an effective therapeutic target for endometrial cancer.

Sputum proteomic analysis for distinguishing between pulmonary tuberculosis and non-tuberculosis using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS): preliminary results

OBJECTIVES

The aim was to evaluate the feasibility and diagnostic contribution of protein profiling using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) applied to sputum to diagnose pulmonary tuberculosis.

METHODS

Sputum samples collected from patients suspected of having pulmonary tuberculosis were analysed using MALDI-TOF MS. Using the differentially expressed protein peaks, we compared three groups of patients, including those with confirmed pulmonary tuberculosis (PTB), those without tuberculosis but with a lower respiratory tract infection (non-TB LRTI) and those without tuberculosis and without an LRTI (non-TB controls).

RESULTS

A total of 102 patients included 35 PTB, 36 non-TB LRTI and 31 non-TB controls. The model differentiated between the PTB patients and the non-TB controls using the 25 most differentially expressed protein peaks, with a sensitivity of 97%, 95% CI 85-100%, and a specificity of 77%, 95% CI 59-90%. The model distinguished the PTB patients from the non-TB LRTI patients using the ten most differentially expressed protein peaks, with a sensitivity of 80%, 95% CI 63-92%, and a specificity of 89%, 95% CI 74-97%. We observed that the negative predictive value of MALDI-TOF MS sputum analysis was higher (96%, 95% CI 80-100%) than that of direct sputum microscopic examination and sputum culture (78%, 95% CI 62-89%) for non-TB controls. When MALDI-TOF MS sputum analysis and direct microscopic examination were combined, the negative predictive value reached 94%, 95% CI 80-99%, for non-TB LRTI patients.

DISCUSSION

These results suggest that MALDI-TOF MS sputum analysis coupled with microscopic examination could be used as a screening tool for diagnosing pulmonary TB.

Characterization of the COPD Salivary Fingerprint through Surface Enhanced Raman Spectroscopy: A Pilot Study

Chronic Obstructive Pulmonary Disease (COPD) is a debilitating pathology characterized by reduced lung function, breathlessness and rapid and unrelenting decrease in quality of life. The severity rate and the therapy selection are strictly dependent on various parameters verifiable after years of clinical observations, missing a direct biomarker associated with COPD. In this work, we report the methodological application of Surface Enhanced Raman Spectroscopy combined with Multivariate statistics for the analysis of saliva samples collected from 15 patients affected by COPD and 15 related healthy subjects in a pilot study. The comparative Raman analysis allowed to determine a specific signature of the pathological saliva, highlighting differences in determined biological species, already studied and characterized in COPD onset, compared to the Raman signature of healthy samples. The unsupervised principal component analysis and hierarchical clustering revealed a sharp data dispersion between the two experimental groups. Using the linear discriminant analysis, we created a classification model able to discriminate the collected signals with accuracies, specificities, and sensitivities of more than 98%. The results of this preliminary study are promising for further applications of Raman spectroscopy in the COPD clinical field.

Electrochemical sensing: A prognostic tool in the fight against COVID-19

The COVID-19 pandemic has devastated the world, despite all efforts in infection control and treatment/vaccine development. Hospitals are currently overcrowded, with health statuses of patients often being hard to gauge. Therefore, methods for determining infection severity need to be developed so that high-risk patients can be prioritized, resources can be efficiently distributed, and fatalities can be prevented. Electrochemical prognostic biosensing of various biomarkers may hold promise in solving these problems as they are low-cost and provide timely results. Therefore, we have reviewed the literature and extracted the most promising biomarkers along with their most favourable electrochemical sensors. The biomarkers discussed in this paper are C-reactive protein (CRP), interleukins (ILs), tumour necrosis factor alpha (TNFα), interferons (IFNs), glutamate, breath pH, lymphocytes, platelets, neutrophils and D-dimer. Metabolic syndrome is also discussed as comorbidity for COVID-19 patients, as it increases infection severity and raises chances of becoming infected. Cannabinoids, especially cannabidiol (CBD), are discussed as a potential adjunct therapy for COVID-19 as their medicinal properties may be desirable in minimizing the neurodegenerative or severe inflammatory damage caused by severe COVID-19 infection. Currently, hospitals are struggling to provide adequate care; thus, point-of-care electrochemical sensor development needs to be prioritized to provide an approximate prognosis for hospital patients. During and following the immediate aftermath of the pandemic, electrochemical sensors can also be integrated into wearable and portable devices to help patients monitor recovery while returning to their daily lives. Beyond the COVID-19 pandemic, these sensors will also prove useful for monitoring inflammation-based diseases such as cancer and cardiovascular disease.

Rapid Detection of Pseudomonas aeruginosa Biofilms via Enzymatic Liquefaction of Respiratory Samples

Respiratory infections caused by multi-drug-resistant Pseudomonas aeruginosa often yield poor outcomes if not detected right away. However, detecting this pathogen in respiratory samples with a rapid diagnostic test is challenging because the protective biofilms created by the pathogen are themselves surrounded by a high-viscosity sputum matrix. Here, we introduce a method for liquefying respiratory samples and disrupting bacterial biofilms on the spot within a minute. It relies on the generation of oxygen bubbles by bacterial catalase through the addition of hydrogen peroxide. When coupled with a mobile biosensor made of paper, the resulting diagnostic kit was able to detect P. aeruginosa infections in sputa from patients with excellent sensitivity and specificity within 8 min. The quick turnaround time along with few infrastructure requirements make this method ideal for the rapid screening of P. aeruginosa infections at the point of care.

Neuromorphic on-chip recognition of saliva samples of COPD and healthy controls using memristive devices

Chronic Obstructive Pulmonary Disease (COPD) is a life-threatening lung disease, affecting millions of people worldwide. Implementation of Machine Learning (ML) techniques is crucial for the effective management of COPD in home-care environments. However, shortcomings of cloud-based ML tools in terms of data safety and energy efficiency limit their integration with low-power medical devices. To address this, energy efficient neuromorphic platforms can be used for the hardware-based implementation of ML methods. Therefore, a memristive neuromorphic platform is presented in this paper for the on-chip recognition of saliva samples of COPD patients and healthy controls. Results of its performance evaluations showed that the digital neuromorphic chip is capable of recognizing unseen COPD samples with accuracy and sensitivity values of 89% and 86%, respectively. Integration of this technology into personalized healthcare devices will enable the better management of chronic diseases such as COPD.

Comparative proteomic analysis of silica-induced pulmonary fibrosis in rats based on tandem mass tag (TMT) quantitation technology

Silicosis is a systemic disease characterized by chronic persistent inflammation and incurable pulmonary fibrosis with the underlying molecular mechanisms to be fully elucidated. In this study, we employed tandem mass tag (TMT) based on quantitative proteomics technology to detect differentially expressed proteins (DEPs) in lung tissues of silica-exposed rats. A total of 285 DEPs (145 upregulated and 140 downregulated) were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to predict the biological pathway and functional classification of the proteins. Results showed that these DEPs were mainly enriched in the phagosome, lysosome function, complement and the coagulation cascade, glutathione metabolism, focal adhesion and ECM-receptor interactions. To validate the proteomics data, we selected and analyzed the expression trends of six proteins including CD14, PSAP, GM2A, COL1A1, ITGA8 and CLDN5 using parallel reaction monitoring (PRM). The consistent result between PRM and TMT indicated the reliability of our proteomic data. These findings will help to reveal the pathogenesis of silicosis and provide potential therapeutic targets. Data are available via ProteomeXchange with identifier PXD020625.

Biosensors for Managing the COVID-19 Cytokine Storm: Challenges Ahead

The global COVID-19 pandemic has oversaturated many intensive care units to the point of collapse, leading to enormous spikes in death counts. Before critical care becomes a necessity, identifying patients who are likely to become critically ill and providing prompt treatment is a strategy to avoid ICU oversaturation. There is a consensus that a hyperinflammatory syndrome or a "cytokine storm" is responsible for poor outcomes in COVID-19. Measuring cytokine levels at the point of care is required in order to better understand this process. In this Perspective, we summarize the main events behind the cytokine storm in COVID-19 as well as current experimental treatments. We advocate for a new biosensor-enabled paradigm to personalize the management of COVID-19 and stratify patients. Biosensor-guided dosing and timing of immunomodulatory therapies could maximize the benefits of these anti-inflammatory treatments while minimizing deleterious effects. Biosensors will also be essential in order to detect complications such as coinfections and sepsis, which are common in immunosuppressed patients. Finally, we propose the ideal features of these biosensors using some prototypes from the recent literature as examples. Multisensors, lateral flow tests, mobile biosensors, and wearable biosensors are seen as key players for precision medicine in COVID-19.

Biosensors for detecting viral and bacterial infections using host biomarkers: a review

A schematic diagram showing multiple modes of biosensing platforms for the diagnosis of bacterial or viral infections.