Mass Spectrometry-Based Untargeted Approaches to Reveal Diagnostic Signatures of Male Infertility in Seminal Plasma: A New Laboratory Perspective for the Clinical Management of Infertility?

Male infertility has been recognized as a global health problem. Semen analysis, although considered the golden standard, may not provide a confident male infertility diagnosis alone. Hence, there is the urgent request for an innovative and reliable platform to detect biomarkers of infertility. The rapid expansion of mass spectrometry (MS) technology in the field of the 'omics' disciplines, has incredibly proved the great potential of MS-based diagnostic tests to revolutionize the future of pathology, microbiology and laboratory medicine. Despite the increasing success in the microbiology area, MS-biomarkers of male infertility currently remain a proteomic challenge. In order to address this issue, this review encompasses proteomics investigations by untargeted approaches with a special focus on experimental designs and strategies (bottom-up and top-down) for seminal fluid proteome profiling. The studies reported here witness the efforts of the scientific community to address these investigations aimed at the discovery of MS-biomarkers of male infertility. Proteomics untargeted approaches, depending on the study design, might provide a great plethora of biomarkers not only for a male infertility diagnosis, but also to address a new MS-biomarkers classification of infertility subtypes. From the early detection to the evaluation of infertility grade, new MS-derived biomarkers might also predict long-term outcomes and clinical management of infertility.

S100A8 and S100A9 in saliva, blood and gingival crevicular fluid for screening established periodontitis: a cross-sectional study

Background

Periodontitis is one of major oral diseases, which has no consensus on early screening tool. This study aimed to compare the association and screening ability of S100A8 and S100A9 in saliva, blood and gingival crevicular fluid (GCF) for periodontitis status.

Methods

We recruited 149 community Korean adults, 50 no or initial periodontitis (NIPERIO) and 99 established periodontitis (PERIO). Using clinical attachment loss and a panoramic radiograph, stage II–IV of new classification of periodontitis proposed at 2018 was considered cases as PERIO. Enzyme linked immunosorbent assay kit was used to quantify S100A8 and S100A9. T-test, analysis of covariance, Mann–Whitney test and correlation analysis were applied to compare the relationship of S100A8 and S100A9 in saliva, blood, and GCF for periodontitis. Receiver operating characteristic curve was applied for screening ability.

Results

Among S100A8 and S100A9 in saliva, blood and GCF, S100A8 in saliva was significantly higher in PERIO than in NIPERIO (p < 0.05). However, S100A8 and S100A9 in GCF were higher in NIPERIO (p < 0.05). The screening ability of salivary S100A8 was 75% for PERIO, while that of GCF S100A8 was 74% for NIPERIO. Salivary S100A8 was positively correlated to blood S100A8 (p < 0.05).

Conclusion

Salivary S100A8 could be a potential diagnostic marker for established periodontitis and be useful for screening established periodontitis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01749-z.

Diagnostic potential and future directions of matrix metalloproteinases as biomarkers in gingival crevicular fluid of oral and systemic diseases

Gingival crevicular fluid (GCF) is a physiological fluid and an inflammatory serum exudate derived from the gingival plexus of blood vessels and mixed with host tissues and subgingival plaque flows. In addition to proteins, GCF contains a diverse population of cells, including desquamated epithelial cells, cytokines, electrolytes, and bacteria from adjacent plaques. Recently, matrix metalloproteinases(MMPs), which are endopeptidases that are active against extracellular macromolecules, in GCF have been revealed as potential utility biomarkers for the diagnosis and follow-up of oral and systemic diseases, thereby facilitating the early evaluation of malignancy risk and the monitoring of disease progression and treatment response. Tissue inhibitors of metalloproteinases (TIMPs) are specific inhibitors of matrixins that participate in the regulation of local activities of MMPs in tissues. This review provides an overview of the latest findings on the diagnostic and prognostic values of MMPs and TIMPs in GCF of oral and systemic diseases, including periodontal disease, pulpitis, peri-implantitis and cardiovascular disease as well as the extraction, detection and analytical methods for GCF.

Dysbiosis From a Microbial and Host Perspective Relative to Oral Health and Disease

The significance of microbiology and immunology with regard to caries and periodontal disease gained substantial clinical or research consideration in the mid 1960's. This enhanced emphasis related to several simple but elegant experiments illustrating the relevance of bacteria to oral infections. Since that point, the understanding of oral diseases has become increasingly sophisticated and many of the original hypotheses related to disease causality have either been abandoned or amplified. The COVID pandemic has reminded us of the importance of history relative to infectious diseases and in the words of Churchill "those who fail to learn from history are condemned to repeat it." This review is designed to present an overview of broad general directions of research over the last 60 years in oral microbiology and immunology, reviewing significant contributions, indicating emerging foci of interest, and proposing future directions based on technical advances and new understandings. Our goal is to review this rich history (standard microbiology and immunology) and point to potential directions in the future (omics) that can lead to a better understanding of disease. Over the years, research scientists have moved from a position of downplaying the role of bacteria in oral disease to one implicating bacteria as true pathogens that cause disease. More recently it has been proposed that bacteria form the ecological first line of defense against "foreign" invaders and also serve to train the immune system as an acquired host defensive stimulus. While early immunological research was focused on immunological exposure as a modulator of disease, the "hygiene hypothesis," and now the "old friends hypothesis" suggest that the immune response could be trained by bacteria for long-term health. Advanced "omics" technologies are currently being used to address changes that occur in the host and the microbiome in oral disease. The "omics" methodologies have shaped the detection of quantifiable biomarkers to define human physiology and pathologies. In summary, this review will emphasize the role that commensals and pathobionts play in their interaction with the immune status of the host, with a prediction that current "omic" technologies will allow researchers to better understand disease in the future.

Diagnostic and Prognostic ability of salivary MMP-9 and S100A8 for periodontitis

OBJECTIVES

Salivary diagnostic using matrix metalloproteinase (MMP) and S100 for periodontitis is a promising issue. However, its prognostic effect is still unclear. This study aimed to evaluate the prognostic ability of salivary MMP-9 and S100A8 for periodontitis through non-surgical periodontitis treatment clinical trial.

MATERIALS AND METHODS

Total 149 participants, 99 periodontitis and 50 healthy, were recruited. Among 99 non-surgical periodontitis treatment participants, 74 participants were revisited after three months. Periodontitis was classified as stage II-IV of new classification of periodontitis proposed at 2018. Enzyme-linked immunosorbent assay kit was used to quantify salivary MMP-9 and S100A8. Receiver operating characteristic curve was applied for diagnostic ability. Paired t test was applied for prognostic ability evaluating changes in salivary markers between pre- and post-treatment.

RESULTS

Salivary MMP-9 and S100A8 were associated with periodontitis (p < .05). The screening ability of algorithm using salivary MMP-9 and S100A8 for periodontitis was 0.86 (p < .05). After treatment, reduction rate of salivary S100A8 and MMP-9 was 83.7% and 23.5%, respectively, (p < .05): only salivary S100A8 was superior compared to clinical parameters.

CONCLUSION

Algorithm using salivary MMP-9 and S100A8 showed high diagnostic power for periodontitis. Both salivary S100A8 and MMP-9 showed prognostic ability for periodontitis, but S100A8 was better.

Gingival Crevicular Fluid Peptidome Profiling in Healthy and in Periodontal Diseases

Given its intrinsic nature, gingival crevicular fluid (GCF) is an attractive source for the discovery of novel biomarkers of periodontal diseases. GCF contains antimicrobial peptides and small proteins which could play a role in specific immune-inflammatory responses to guarantee healthy gingival status and to prevent periodontal diseases. Presently, several proteomics studies have been performed leading to increased coverage of the GCF proteome, however fewer efforts have been done to explore its natural peptides. To fill such gap, this review provides an overview of the mass spectrometric platforms and experimental designs aimed at GCF peptidome profiling, including our own data and experiences gathered from over several years of matrix-assisted laser desorption ionization/time of flight mass spectrometry (MALDI-TOF MS) based approach in this field. These tools might be useful for capturing snapshots containing diagnostic clinical information on an individual and population scale, which may be used as a specific code not only for the diagnosis of the nature or the stage of the inflammatory process in periodontal disease, but more importantly, for its prognosis, which is still an unmet medical need. As a matter of fact, current peptidomics investigations suffer from a lack of standardized procedures, posing a serious problem for data interpretation. Descriptions of the efforts to address such concerns will be highlighted.

Host-microbe interactions: Profiles in the transcriptome, the proteome, and the metabolome

Periodontal studies using transcriptomics, proteomics, and metabolomics encompass the collection of mRNA transcripts, proteins, and small-molecule chemicals in the context of periodontal health and disease. The number of studies using these approaches has significantly increased in the last decade and they have provided new insight into the pathogenesis and host-microbe interactions that define periodontal diseases. This review provides an overview of current molecular findings using -omic approaches that underlie periodontal disease, including modulation of the host immune response, tissue homeostasis, and complex metabolic processes of the host and the oral microbiome. Integration of these -omic approaches will broaden our perspective of the molecular mechanisms involved in periodontal disease, advancing and improving the diagnosis and treatment of various stages and forms of periodontal disease.

Rapid diagnosis of periodontitis, a feasibility study using MALDI-TOF mass spectrometry

AIM

The aim of the present study was to assess the feasibility and diagnostic contribution of protein profiling using MALDI-TOF mass spectrometry applied to saliva, gingival crevicular fluid (GCF) and dental plaque from periodontitis and healthy subjects. We hypothesized that rapid routine and blinded MALDI-TOF analysis could accurately classify these three types of samples according to periodontal state.

MATERIALS AND METHODS

Unstimulated saliva, GCF and dental plaque, collected from periodontitis subjects and healthy controls, were analyzed by MALDI-TOF MS. Based on the differentially expressed peaks between the two groups, diagnostic decision trees were built for each sample.

RESULTS

Among 141 patients (67 periodontitis and 74 healthy controls), the decision trees diagnosed periodontitis with a sensitivity = 70.3% (± 0.211) and a specificity = 77.8% (± 0.165) for saliva, a sensitivity = 79.6% (± 0.188) and a specificity = 75.7% (± 0.195) for GCF, and a sensitivity = 72.1% (± 0.202) and a specificity = 72.2% (± 0.195) for dental plaque. The sensitivity and specificity of the tests were improved to 100% (CI 95% = [0.91;1]) and 100% (CI 95% = [0.92;1]), respectively, when two samples were tested.

CONCLUSION

We developed, for the first time, diagnostic tests based on protein profiles of saliva, GCF and dental plaque between periodontitis patients and healthy subjects. When at least 2 of these samples were tested, the best results were obtained.

Top-Down and Bottom-Up Proteomics of Circulating S100A8/S100A9 in Plasma of Septic Shock Patients

Well-characterized prognostic biomarkers and reliable quantitative methods are key in sepsis management. Among damage-associated molecular patterns, S100A8/S100A9 complexes are reported to be markers for injured cells and to improve the prediction of death in septic shock patients. In view of the structural diversity observed for the intracellular forms, insight into circulating complexes and proteoforms is required to establish prognostic biomarkers. Here, we developed top-down and bottom-up proteomics to characterize the association of S100A8 and S100A9 in complexes and major circulating proteoforms. An antibody-free method was developed for absolute quantification of S100A8/S100A9 in a cohort of 49 patients to evaluate the prognostic value on the first day after admission for septic shock. The predominant circulating forms identified by top-down proteomics were S100A8, mono-oxidized S100A8, truncated acetylated S100A9, and S-nitrosylated S100A9. S100A8, truncated acetylated S100A9, and mono-oxidized S100A8 discriminated between survivors and nonsurvivors, along with total S100A8/S100A9 measured by the antibody-free bottom-up method. Overall, new insights into circulating S100A8/S100A9 and confirmation of its prognostic value in septic shock are crucial in qualification of this biomarker. Also, the simple antibody-free assay would support the harmonization of S100A8/S100A9 measurements.

Minimally invasive non-surgical vs. surgical approach for periodontal intrabony defects: a randomised controlled trial

Background

Periodontal intrabony defects are usually treated surgically with the aim of increasing attachment and bone levels and reducing risk of progression. However, recent studies have suggested that a minimally invasive non-surgical therapy (MINST) leads to considerable clinical and radiographic defect depth reductions in intrabony defects. The aim of this study is to compare the efficacy of a modified MINST approach with a surgical approach (modified minimally invasive surgical therapy, M-MIST) for the treatment of intrabony defects.

Methods

This is a parallel-group, single-centre, examiner-blind non-inferiority randomised controlled trial with a sample size of 66 patients. Inclusion criteria are age 25–70, diagnosis of periodontitis stage III or IV (grades A to C), presence of ≥ 1 ‘intrabony defect’ with probing pocket depth (PPD) > 5 mm and intrabony defect depth ≥ 3 mm. Smokers and patients who received previous periodontal treatment to the study site within the last 12 months will be excluded. Patients will be randomly assigned to either the modified MINST or the M-MIST protocol and will be assessed up to 15 months following initial therapy. The primary outcome of the study is radiographic intrabony defect depth change at 15 months follow-up. Secondary outcomes are PPD and clinical attachment level change, inflammatory markers and growth factors in gingival crevicular fluid, bacterial detection, gingival inflammation and healing (as measured by geometric thermal camera imaging in a subset of 10 test and 10 control patients) and patient-reported outcomes.

Discussion

This study will produce evidence about the clinical efficacy and potential applicability of a modified MINST protocol for the treatment of periodontal intrabony defects, as a less invasive alternative to the use of surgical procedures.

Trial registration

ClinicalTrials.gov, NCT03797807. Registered on 9 January 2019.

Comparative evaluation of Gingival Crevicular Fluid (GCF) levels of Interleukin-34 levels in periodontally healthy and in patients with chronic and aggressive periodontitis- A cross-sectional study

Background and objectives

Proinflammatory cytokines appear to have a central role in the destruction of periodontal tissues. By binding to Receptor Activator of Nuclear Factor κb (RANK) on osteoclast progenitor cells, these cytokines are locally responsible for the activation of bone resorbing osteoclasts differentiation and function. Interleukin-34 (IL-34) is a proinflammatory cytokine derived from the osteoblasts and plays an important role in osteoclastogenesis. The present study was carried out to assess the levels of IL-34 in Gingival Crevicular Fluid (GCF) in periodontally healthy patients, chronic periodontitis and aggressive periodontitis.

Materials and method

A total of 90 patients were recruited in the study and were divided into 3 groups: Periodontally healthy patients (Group I), Chronic periodontitis (Group II) and Aggressive periodontitis (Group III). Clinical Parameters like plaque index, gingival index, probing depth, clinical attachment levels were recorded and GCF samples were collected at baseline for the assessment of IL-34 levels in all the three groups. IL-34 levels were calculated using Enzyme-Linked Immune-Sorbent Assay (ELISA).

Results

The mean GCF levels of IL-34 in Group I was 47.22 ± 18.04 pg/ml, Group II was 103.76 ± 26.61 pg/ml and in Group III was 191.71 ± 49.24 pg/ml. The mean GCF IL-34 level was found to be higher in Group III followed by Group II and Group I. The IL-34 levels correlated with clinical parameters like plaque index, gingival index, probing depth, clinical attachment levels. But correlation with probing depth and clinical attachment level were significantly higher in Group III followed by Group II and Group I.

Interpretation and conclusion

The study demonstrated higher levels of IL-34 in aggressive periodontitis when compared with chronic periodontitis. IL-34, a novel diagnostic marker which was found to be at higher level in GCF of aggressive and chronic periodontitis patients.

Proteomic analysis of gingival crevicular fluid for novel biomarkers of pubertal growth peak

Background

Detection of pubertal growth peak is vital in orthodontic treatment timing and planning. Gingival crevicular fluid (GCF) contains abundant proteins from different sources and is an ideal source of biomarkers. The aim of this research is to detect candidate GCF biomarkers of pubertal growth by tandem mass tags (TMT) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) to help diagnosis and treatment planning of functional treatment.

Methods

Forty subjects were recruited and were divided into pubertal and post-pubertal groups according to cervical vertebral maturation method. GCF samples were collected by paper points. GCF proteome of pubertal and post-pubertal subjects was compared by TMT labelling coupled with LC-MS/MS.

Results

A total of 537 proteins were detected in GCF samples, with 183 proteins detected in GCF for the first time. These proteins were involved in processes of immune response, ion transport, and signal transduction. The GCF concentration of vitamin D binding protein (DBP) and seroserotransferrin (Tf) was significantly higher in pubertal than that in post-pubertal subjects. DBP and Tf, therefore, were considered to be candidate biomarkers of pubertal growth. This result was validated using GCF samples from new subjects (P < 0.05).

Conclusion

Our results indicate that TMT labelling coupled with LC-MS/MS were proved to be a useful method for proteomic analysis of GCF with high accuracy. The expression of DBP and Tf was increased in children at circumpubertal stage and can be considered candidate biomarkers of pubertal growth.

Salivary S100 proteins screen periodontitis among Korean adults

AIM

This study aims to evaluate the association of salivary S100A8 and A9 proteins with periodontitis and its screening ability for periodontitis cross-sectionally.

MATERIAL AND METHODS

We selected 326 participants from the Yangpyeong Cohort: 218 participants with periodontitis and 108 participants without periodontitis. Stage II-IV periodontitis according to the modification of new international classification of periodontitis was considered as periodontitis. S100A8 and A9 were assayed using enzyme-linked immunosorbent assay kit. Age, sex, education, smoking, drinking, exercise, and metabolic syndrome were factored as confounders. Analyses of covariance and logistic regression analysis were applied to evaluate the association of S100A8 and A9 with periodontitis. Receiver operating characteristic curve was applied for screening ability.

RESULTS

Those with periodontitis compared to those without periodontitis showed higher adjusted amount of S100A8 (3694 versus 6757 ng/ml, p < 0.001), but less adjusted amount of S100A9 (1341 versus 1030 ng/ml, p = 0.015). The screening ability of S100A8 and A9 on periodontitis was c-statistics of 0.69 (p < 0.001) for both S100A8 and A9, 0.67 for S100A8 and 0.63 (p < 0.001) for S100A9.

CONCLUSIONS

Overall, salivary S100A8 and S100A9 could be practical markers for periodontitis. Its screening ability for periodontitis could be beneficial in clinics and at home.

Plasma Peptidome Pattern of Breast Cancer Using Magnetic Beads-Based Plasma Fractionation and MALDI-TOF MS: A Case Control Study in Egypt

Objective: The present study aimed to determine peptidome patterns in breast cancer (BC). Methods: We analyzed the plasma proteomic profiling of 80 BC patients and 50 healthy controls, using hydrophobic interaction chromatography magnetic beads (MB-HIC8) separation followed by Matrix assisted laser desorption ionization/ time of flight mass spectrometry (MALDI-TOF MS). Results: ClinProTools software identified 92 peaks that differed among the analyzed groups, 33 peaks were significantly different (P < 0.05). Of those, 22 peaks were up-regulated while 11 peaks were down-regulated in BC patients compared with the healthy controls. Three peptide ion signatures (m/z 1,570.31, 1,897.4 and 2,568.17) were provided by the Quick Classifier model to discriminate BC patients from healthy control subjects with 96.4% accuracy. External validation was performed by an independent group and this achieved a sensitivity of 100% and a specificity of 76.9%. Conclusion: MALDI-TOF MS has good analytical performance in distinguishing BC patients from healthy controls.

Applications of MALDI-TOF mass spectrometry in clinical proteomics

INTRODUCTION

The development of precision medicine requires advanced technologies to address the multifactorial disease stratification and to support personalized treatments. Among omics techniques, proteomics based on Mass Spectrometry (MS) is becoming increasingly relevant in clinical practice allowing a phenotypic characterization of the dynamic functional status of the organism. From this perspective, Matrix Assisted Laser Desorption Ionization Time of Flight (MALDI-TOF) MS is a suitable platform for providing a high-throughput support to clinics. Areas covered: This review aims to provide an updated overview of MALDI-TOF MS applications in clinical proteomics. The most relevant features of this analysis have been discussed, highlighting both pre-analytical and analytical factors that are crucial in proteomics studies. Particular emphasis is placed on biofluids proteomics for biomarkers discovery and on recent progresses in clinical microbiology, drug monitoring, and minimal residual disease (MRD). Expert commentary: Despite some analytical limitations, the latest technological advances together with the easiness of use, the low time and low cost consuming and the high throughput are making MALDI-TOF MS instruments very attractive for the clinical practice. These features offer a significant potential for the routine of the clinical laboratory and ultimately for personalized medicine.

Gingival Crevicular Fluid as a Novel Potential Source of Biomarkers Distinguishes Pubertal from Post-Pubertal Subjects

Detection of pubertal growth peak is vital in orthodontic treatment timing and planning. Gingival crevicular fluid (GCF) contains abundant proteins from different sources and has been proven to be an ideal source of biomarkers. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS) is an advanced technique that can detect low-molecular-weight peptides with high sensitivity and resolution. The aim of this research was to identify novel candidate biomarkers in GCF to help the diagnosis of pubertal growth peak by MALDI-TOF/MS. Results showed that the peak intensities of six peptides were significantly different between two groups: 1660.2 Da, 1783.0 Da, 2912.5 Da, 4178.6 Da, 5064.9 Da, and 6108.9 Da and are considered to be potential candidate biomarkers to identify pubertal growth peak. Further studies are needed to identify sequence information of these candidate biomarkers.