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

Biomarkers in Body Fluids as Indicators of Skeletal Maturity: A Systematic Review and Meta-analysis

OBJECTIVES

This review aimed to critically appraise the evidence for biomarkers in blood serum, gingival crevicular fluid (GCF), saliva, and urine in comparison with standard radiographic indices for skeletal maturation assessment.

MATERIALS AND METHODS

A thorough literature search in multiple databases was conducted for biomarkers in body fluids for skeletal maturation assessed with cervical vertebrae in lateral cephalograms or on hand-wrist radiographs. Different combinations including free text, MeSH terms, and Boolean operators were used. Two researchers used strict inclusion and exclusion criteria to screen title, abstract, and full text, and used the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 instrument for risk of bias assessment of individual studies. Meta-analysis was performed on eligible studies using RevMan 5 software.

RESULTS

A total of 344 articles were screened, of which 33 met the inclusion criteria and quality assessment. The skeletal maturity indicators included insulin-like growth factors (IGF-1), alkaline phosphatase (ALP), bone-specific alkaline phosphatase (BALP), dehydroepiandrosterone sulfate (DHEAS), vitamin D binding protein (DBP), parathormone-related protein (PTHrP), osteocalcin, metalloproteins, and serotransferrin (TF) along with different metabolites. At puberty, a significant rise was seen in IGF-1, DBP, ALP, osteocalcin, TF, and BALP. However, the serum DHEAS and PTHrP increased from pre-pubertal to post-pubertal stages. Due to the data heterogeneity, a meta-analysis could be performed on seven studies in total on IGF-1 in serum and blood. Of these, five were included for data in males and six in females, and four studies on IGF-1 in serum and blood. A significant difference in IGF-1 levels was seen between stages of peak pubertal growth spurt (CS3 and CS4) and decelerating pubertal growth (CS5) compared with growth initiation stage (CS2).

CONCLUSIONS

Pubertal growth spurts were correlated with peak serum IGF-1 and BALP in both sexes individually. Peak ALP levels in GCF were correlated with the pubertal spurt in a combined sample of males and females. Standard biofluid collection protocols and homogeneity in sampling and methodology are strongly recommended for future research.

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.

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.

Human Gingival Crevicular Fluids (GCF) Proteomics: An Overview

Like other fluids of the human body, a gingival crevicular fluid (GCF) contains proteins, a diverse population of cells, desquamated epithelial cells, and bacteria from adjacent plaque. Proteomic tools have revolutionized the characterization of proteins and peptides and the detection of early disease changes in the human body. Gingival crevicular fluids (GCFs) are a very specific oral cavity fluid that represents periodontal health. Due to their non-invasive sampling, they have attracted proteome research and are used as diagnostic fluids for periodontal diseases and drug analysis. The aim of this review is to explore the proteomic science of gingival crevicular fluids (GCFs), their physiology, and their role in disease detection.