An Overview of Physical, Microbiological and Immune Barriers of Oral Mucosa

Microbial functional pathways based on metatranscriptomic profiling enable effective saliva-based health assessments for precision wellness

It is increasingly recognized that an important step towards improving overall health is to accurately measure biomarkers of health from the molecular activities prevalent in the oral cavity. We present a general methodology for computationally quantifying the activity of microbial functional pathways using metatranscriptomic data. We describe their implementation as a collection of eight oral pathway scores using a large salivary sample dataset (n = 9350), and we evaluate score associations with oropharyngeal disease phenotypes within an unseen independent cohort (n = 14,129). Through this validation, we show that the relevant oral pathway scores are significantly worse in individuals with periodontal disease, acid reflux, and nicotine addiction, compared with controls. Given these associations, we make the case to use these oral pathway scores to provide molecular health insights from simple, non-invasive saliva samples, and as molecular endpoints for actionable interventions to address the associated conditions.

Efficacy and tolerability of SEDIFLÙ in treating dry or productive cough in the pediatric population (SEPEDIA): A pilot, randomized, double-blind, placebo-controlled, multicenter clinical trial

The aim of this trial was to assess the effectiveness of Sediflù, a medical device containing active herbal ingredients, on nocturnal and diurnal persistent coughs in children, with a duration of 3 to 7 days. Children with a dry and/or productive cough were enrolled in this prospective, interventional, multicenter, placebo-controlled, double-blind, randomized clinical study. Clinical efficacy was assessed through the evaluation of the soothing action of Sediflù against dry and/or productive coughing, both at night and during the day, and other effects of coughing associated with quality of sleep: frequency, child's quality of sleep, parental quality of sleep and severity. Treatment with Sediflù improved both night-time and day-time cough scores from day 2. The diurnal score also improved significantly in the Sediflù group at days 3 and 7. Sediflù syrup can be considered a valid treatment for cough management in younger children with upper respiratory tract infections, shortening the cough duration.

Development of an Oral Epithelial Ex Vivo Organ Culture Model for Biocompatibility and Permeability Assessment of Biomaterials

In the present study, a customized device (Epi-ExPer) was designed and fabricated to facilitate an epithelial organ culture, allowing for controlled exposure to exogenous chemical stimuli and accommodating the evaluation of permeation of the tissue after treatment. The Epi-ExPer system was fabricated using a stereolithography (SLA)-based additive manufacturing (AM) method. Human and porcine oral epithelial mucosa tissues were inserted into the device and exposed to resinous monomers commonly released by dental restorative materials. The effect of these xenobiotics on the morphology, viability, permeability, and expression of relevant markers of the oral epithelium was evaluated. Tissue culture could be performed with the desired orientation of air-liquid interface (ALI) conditions, and exposure to xenobiotics was undertaken in a spatially guarded and reproducible manner. Among the selected monomers, HEMA and TEGDMA reduced tissue viability at high concentrations, while tissue permeability was increased by the latter. Xenobiotics affected the histological image by introducing the vacuolar degeneration of epithelial cells and increasing the expression of panCytokeratin (pCK). Epi-ExPer device offers a simple, precise, and reproducible study system to evaluate interactions of oral mucosa with external stimuli, providing a biocompatibility and permeability assessment tool aiming to an enhanced in vitro/ex vivo-to-in vivo extrapolation (IVIVE) that complies with European Union (EU) and Food and Durg Administration (FDI) policies.

Efficacy of nebulized GM-CSF inhalation in preventing oral mucositis in patients undergoing hematopoietic stem cell transplantation: A retrospective study

Objective

To study the efficacy of oxygen atomization inhalation of granulocyte-macrophage colony-stimulating factor (GM-CSF) for preventing oral mucositis in patients following hematopoietic stem cell transplantation.

Methods

Data from patients who received hematopoietic stem cell transplantation and were treated with GM-CSF for the prevention/treatment of oral mucositis in our hospital from June 2021 to June 2023 were collected. The enrolled patients were divided into an observation group and a control group according to the use of GM-CSF. The WHO Mucositis Scale Assessment Criteria were utilized to evaluate the characteristics of patients with oral mucositis (OM) from the beginning of the pretreatment period until they were discharged from the hospital. The general data, preconditioning protocol, transplantation method, overall grade and duration of oral mucositis, pain score, nutritional score and number of days of parenteral nutrition use, oral mucosal infection status and antibiotic use intensity, the granulocyte and megakaryocyte reconstruction time, and adverse reaction reports of the patients were collected and summarized through the medical records system.

Results

A total of 143 patients were included in this study, including 75 patients in the observation group. In the observation group, there were 36 males and 39 females aged 22-67 years. There were 45 patients who received autologous transplantation and 30 patients who received allogeneic transplantation. In terms of the disease distribution, there were 33 cases of leukemia, 24 cases of lymphoma, 11 cases of multiple myeloma, and 8 other cases (3 cases of aplastic anemia, 2 cases of myelodysplastic syndrome, 2 cases of myelofibrosis, 1 case of POEMS syndrome). There were 68 patients in the control group, including 33 males and 35 females; the control group patients were aged 25-74years. Forty-one patients received autologous transplantation, and 27 patients received allogeneic transplantation. The disease distribution included 29 cases of leukemia, 17 cases of lymphoma, 12 cases of multiple myeloma, and 7 other cases (3 cases of aplastic anemia, 2 cases of myelodysplastic syndrome, 1 case of myelofibrosis, 1 case of POEMS syndrome). There were no significant differences between the two groups concerning age, sex, disease distribution or the transplantation method (P > 0.05). In the observation group, 13 cases did not develop oral mucositis, and 32 cases developed oral mucositis (16 cases of Grade I, 14 cases of Grade II, 2 cases of Grade III, and 0 cases of Grade IV). In the control group, there were 5 cases without mucositis and 36 cases with oral mucositis (6 cases of Grade Ⅰ, 16 cases of Grade Ⅱ, 8 cases of Grade Ⅲ, and 6 cases of Grade Ⅳ), the difference was statistically significant (P < 0.05). The pain score and duration of mucositis in the observation group were significantly lower than those in the control group (P < 0.05). In addition, the oral infection rate, antibiotic use intensity, nutritional score, per capita number of days of parenteral nutrition use and hematopoietic reconstruction time in the observation group were significantly lower than those in the control group (P < 0.05). In the observation group, 8 patients did not develop oral mucositis, and 22 patients developed oral mucositis (13 cases of Grade I, 7 cases of Grade II, 1 case of Grade III, and 1 case of Grade IV). In the control group, 1 case did not develop mucositis, and 26 cases developed oral mucositis (3 cases of Grade Ⅰ, 10 cases of Grade Ⅱ, 9 cases of Grade Ⅲ, and 4 cases of Grade Ⅳ). The difference was statistically significant (P < 0.05). The pain score and duration of mucositis in the observation group were significantly lower than those in the control group (P < 0.05). In addition, the oral mucosal infection rate, antibiotic use intensity, nutritional score, per capita number of days of parenteral nutrition use and hematopoietic reconstruction time in the observation group were significantly lower than those in the control group (P < 0.05). No adverse reactions were reported in either group.

Conclusion

In both autologous transplantation and allogeneic transplantation patients, GM-CSF atomized inhalation can improve the prevention and treatment of oral mucositis in stem cell transplantation patients, reduce the incidence of oral infection, reduce the intensity of antibiotic use and the number of days of parenteral nutrition use, and thus promote the process of hematopoietic reconstruction.

Streptococcus salivarius ameliorates the destructive effect on the epithelial barrier by inhibiting the growth of Prevotella melaninogenica via metabolic acid production

BACKGROUND

Oral lichen planus (OLP) is one of the most common oral mucosal diseases, exhibiting a higher prevalence in women than men, but its pathogenesis is still unclear. Current research suggests that microbial dysbiosis may play an important role in the pathogenesis of OLP. Our previous research has found that the increase of Prevotella melaninogenica and decrease of Streptococcus salivarius have been identified as a potential pathogenic factor in OLP. Consequently, the objective of this study is to examine whether S. salivarius can counteract the detrimental effects of P. melaninogenica on the integrity of the epithelial barrier function.

MATERIALS AND METHODS

Epithelial barrier disruption was induced by P. melaninogenica in human keratinocytes (HaCaT cells). HaCaT cells were pretreated with S. salivarius(MOI = 20) or cell-free supernatant for 3 h, followed by treatment with P. melaninogenica (MOI = 5) for 3 h. The epithelial barrier integrity of HaCaT cells was detected by FD4 permeability. The mRNA level of tight junction protein was detected by quantitative real-time polymerase chain reaction (PCR). Immunofluorescence and Western Blot were used to detect the protein expression of zonula occludin-1 (ZO-1). The serial dilution-spotting assay was applied to monitor the viability of P. melaninogenica at the end of 8 and 24 h incubation.

RESULTS

Challenge by P. melaninogenica decreased the levels of tight junction proteins, including occludin, ZO-1, and claudin in HaCaT cells. S. salivarius or its cell-free supernatant inhibited the down-regulation of ZO-1 mRNA and protein expression levels induced by P. melaninogenica and thus improved the epithelial barrier function. The inhibitory effect of the cell-free supernatant of S. salivarius on the growth of P. melaninogenica is associated with metabolic acid production rather than with bacteriocins and hydrogen peroxide.

CONCLUSIONS

These results suggest that live S. salivarius or its cell-free supernatant significantly ameliorated the disruption of epithelial tight junctions induced by P. melaninogenica, likely through the inhibition of P. melaninogenica growth mediated by metabolic acid production.

Toward Digital Periodontal Health: Recent Advances and Future Perspectives

Periodontal diseases, ranging from gingivitis to periodontitis, are prevalent oral diseases affecting over 50% of the global population. These diseases arise from infections and inflammation of the gums and supporting bones, significantly impacting oral health. The established link between periodontal diseases and systemic diseases, such as cardiovascular diseases, underscores their importance as a public health concern. Consequently, the early detection and prevention of periodontal diseases have become critical objectives in healthcare, particularly through the integration of advanced artificial intelligence (AI) technologies. This paper aims to bridge the gap between clinical practices and cutting-edge technologies by providing a comprehensive review of current research. We examine the identification of causative factors, disease progression, and the role of AI in enhancing early detection and treatment. Our goal is to underscore the importance of early intervention in improving patient outcomes and to stimulate further interest among researchers, bioengineers, and AI specialists in the ongoing exploration of AI applications in periodontal disease diagnosis.

Applications of Chitosan in Prevention and Treatment Strategies of Infectious Diseases

Chitosan is the most commonly investigated functional cationic biopolymer in a wide range of medical applications due to its promising properties such as biocompatibility, biodegradability, and bioadhesivity, as well as its numerous bioactive properties. Within the last three decades, chitosan and its derivatives have been investigated as biomaterials for drug and vaccine delivery systems, besides for their bioactive properties. Due to the functional groups in its structure, it is possible to tailor the delivery systems with desired properties. There has been a great interest in the application of chitosan-based systems also for the prevention and treatment of infectious diseases, specifically due to their antimicrobial, antiviral, and immunostimulatory effects. In this review, recent applications of chitosan in the prevention and treatment of infectious diseases are reviewed, and possibilities and limitations with regards to technical and regulatory aspects are discussed. Finally, the future perspectives on utilization of chitosan as a biomaterial are discussed.

A hyaluronic acid-based dissolving microneedle patch loaded with 5-aminolevulinic acid for improved oral leukoplakia treatment

INTRODUCTION

A local microneedle patch loaded with 5-aminolevulinic acid (ALA) was constructed to improve the efficiency of ALA photodynamic treatment of oral leukoplakia, reduce local photosensitivity reactions, and promote the healing of lesions.

METHODS

The microneedle patch loaded with ALA was constructed with the hyaluronic acid (HA) solution (ALA-HAMN), and its morphology, strength, mucosal penetration, and biocompatibility were tested.

RESULTS

In vivo safety and permeability tests confirmed that ALA-HAMN had good biocompatibility and could penetrate the mucosal barrier and quickly dissolve and release ALA for in situ transdermal administration. The 4-nitroquinoline oxide (NQO) rat model experiment showed that ALA-HAMN can significantly improve photodynamic therapy (PDT) efficiency and has no damage to mucosal tissue compared with the commonly used ALA cotton ball dressing.

CONCLUSIONS

The ALA-loaded microneedle patch was successfully constructed for the photodynamic treatment of oral leukoplakia, and the photodynamic efficiency and comfort of oral leukoplakia were improved, which provided an effective delivery mode to improve clinical ALA-PDT treatment of oral leukoplakia (OLK).

Oral Patch/Film for Drug Delivery-Current Status and Future Prospects

In recent years, there has been extensive research into drug delivery systems aimed at enhancing drug utilization while minimizing drug toxicities. Among these systems, oral patches/films have garnered significant attention due to their convenience, noninvasive administration, ability to bypass hepatic first-pass metabolism, thereby enhancing drug bioavailability, and their potential to ensure good compliance, particularly among special patient populations. In this review, from the perspective of the anatomical characteristics of the oral cavity and the advantages and difficulties of oral drug delivery, we illustrate the design ideas, manufacturing techniques, research methodologies, and the essential attributes of an ideal oral patch/film. Furthermore, the applications of oral patches/films in both localized and systemic drug delivery were discussed. Finally, we offer insights into the future prospects of the oral patch/film, aiming to provide valuable reference for the advancement of oral localized drug delivery systems.

The mucosal immunity in crustaceans: Inferences from other species

Crustaceans such as shrimps and crabs, hold significant ecological significance and substantial economic value within marine ecosystems. However, their susceptibility to disease outbreaks and pathogenic infections has posed major challenges to production in recent decades. As invertebrate, crustaceans primarily rely on their innate immune system for defense, lacking the adaptive immune system found in vertebrates. Mucosal immunity, acting as the frontline defense against a myriad of pathogenic microorganisms, is a crucial aspect of their immune repertoire. This review synthesizes insights from comparative immunology, highlighting parallels between mucosal immunity in vertebrates and innate immune mechanisms in invertebrates. Despite lacking classical adaptive immunity, invertebrates, including crustaceans, exhibit immune memory and rely on inherent "innate immunity factors" to combat invading pathogens. Drawing on parallels from mammalian and piscine systems, this paper meticulously explores the complex role of mucosal immunity in regulating immune responses in crustaceans. Through the extrapolation from well-studied models like mammals and fish, this review infers the potential mechanisms of mucosal immunity in crustaceans and provides insights for research on mucosal immunity in crustaceans.

Oral Diseases as a Manifestation of Inborn Errors of Immunity

Oral findings such as inflammation, ulcerations, or lesions can indicate serious systemic diseases and should prompt suspicion of acquired chronic conditions or inborn errors of immunity (IEIs). Currently, there are approximately 500 disease entities classified as IEIs, with the list expanding annually. The awareness of the existence of such conditions is of paramount importance, as patients with these disorders frequently necessitate the utilization of enhanced diagnostic techniques. This is exemplified by patients with impaired antibody production, in whom conventional serological methods may prove to be undiagnostic. Patients with IEI may require distinct therapeutic approaches or antimicrobial prophylaxis throughout their lives. An accurate diagnosis and, more importantly, early identification of patients with immune deficiencies is crucial to ensure the quality and longevity of their lives. It is important to note that the failure to establish a proper diagnosis or to provide adequate treatment could also have legal implications for medical professionals. The article presents IEIs, which may manifest in the oral cavity, and their diagnosis alongside therapeutic procedures.

Assessing oral health knowledge among public school children in Saudi Arabian subpopulation

INTRODUCTION

Oral hygiene is paramount for maintaining optimal oral and physical health, especially among children who are particularly susceptible to dental caries and issues due to dietary habits and inadequate hygiene practices. This study aimed to evaluate the awareness and knowledge of oral health among public school children, analyse their oral hygiene habits, educate parents on the importance of oral health for their children, and implement an oral hygiene educational program in Al-Kharj City, Saudi Arabia.

METHODS

Four public elementary schools were selected for the study, with a sample size of 200 school-going children participating. A structured questionnaire was used to assess awareness and knowledge of oral health among the participants. SPSS software version 26 was used for data analysis. Multiple regression analysis and correlation tests was employed to explore the relationships between the different variables measured in the study.

RESULTS

The findings revealed a significant lack of awareness regarding oral health among school children. Oral hygiene habits were found to be inadequate in many participants. Overall, the findings highlight the need for targeted interventions aimed at promoting regular dental visits, addressing dental fear, and fostering positive oral hygiene practices among school-going children to improve oral health outcomes in the studied population.

CONCLUSION

The study highlighted a critical gap in oral health awareness among school children, underscoring the need for targeted interventions. While the oral hygiene educational program has been implemented and future data will shed light on its effectiveness, preliminary observations suggest that such programs could potentially improve oral health outcomes and overall engagement among students.

Early intervention with oral mucosal barrier Protective agents in chronic oral graft-versus-host disease: a retrospective cohort study

BACKGROUND

Preventing the progression of chronic oral graft-versus-host disease (cGVHD) is essential for maintaining oral health, improving quality of life, minimizing functional impairment, reducing systemic complications, and addressing treatment challenges.

PURPOSE

To evaluate the effectiveness of early intervention with oral mucosal barrier protective agents in preventing the progression of cGVHD and its impact on oral health, quality of life, and treatment response.

METHODS

This retrospective cohort study included 75 participants, with 34 in the non-oral mucosal barrier protective agent group and 41 in the oral mucosal barrier protective agent group. Baseline characteristics, oral mucosal health parameters, quality of life assessments, and curative effect data were collected and compared between the two study groups.

RESULTS

The group receiving oral mucosal barrier protectants (n = 41) exhibited significantly lower severity of oral mucositis compared to the group without such protectants (n = 34) (2.12 ± 0.48 vs. 2.56 ± 0.63, P = 0.001) and the incidence of complications was significantly lower in the group receiving oral mucosal barrier protectants (P < 0.05). Additionally, the quality of life assessment showed marked improvements in somatization, emotional management, and social reintegration in the oral mucosal barrier protectant group compared to the group without these protectants (P < 0.05). Furthermore, the assessment of treatment efficacy revealed significantly higher rates of both complete and partial responses in the oral mucosal barrier protectant group, along with a notable reduction in disease progression compared to the group without these protectants (P < 0.001).

CONCLUSION

Early intervention with oral mucosal barrier protective agents was associated with improved oral health parameters, enhanced quality of life, and a more favorable treatment response in the context of cGVHD.

Computational bioprospecting of phytoconstituents as potential inhibitors for peptide deformylase from Streptococcus oralis: An opportunistic pathogen

Streptococcus oralis an opportunistic bacterium has been reported to be involved in various blood borne infections like subacute bacterial endocarditis, septicemia, bacterial meningitis and in some cases dental caries too. Among various targets the peptide deformylase, of S.oralis appears to be most potent druggable target as it is involved in protein synthesis is opted for the current study. Due to unavailability of PDB structure of peptide deformylase from S. oralis the study initiates with homology modelling of the protein and 6OW2 of S pneumoniae is considered as the template. Thereafter, Molecular docking, Molecular dynamic simulation, ADME analysis, and MMPBSA analysis was carried out to explore the inhibitory potential of phyto-constituents as potential inhibitors for Peptide deformylase from S.oralis. Actinonin was considered as reference drug. Among 2370 phyto compounds the best observations were recorded for A1-Barrigenol (IMPHY010984) with binding affinity of -8.5 kcal/mol. Calculated RMSD, RMSF, Binding Free Energy for IMPHY010984 averaged at about 0.10 ± 0.03 nm, 0.08 ± 0.05 nm, 131 ± 21 kJ/mol respectively whereas the RMSD, RMSF, Binding Free Energy recorded for reference drug averaged at about 0.19 ± 0.04 nm, 0.11 ± 0.08 nm, -94 ± 18 kJ/mol respectively. Based on in silico observations IMPHY010984 is proved out as superior candidate over reference drug. The study reflects the potential of IMPHY010984 as prophylactic therapeutics for S.oralis.

Pilot Evaluation of Silicone Surrogates for Oral Mucosa Simulation in Craniofacial Surgical Training

Surgical simulators are crucial in early craniofacial and plastic surgical training, necessitating synthetic materials that accurately replicate tissue properties. Recent critiques of our lab's currently deployed silicone surrogate have highlighted numerous areas for improvement. To further refine our models, our group's objective is to find a composition of materials that is closest in fidelity to native oral mucosa during surgical rehearsal by expert craniofacial surgeons. Fifteen platinum silicone-based surrogate samples were constructed with variable hardness and slacker percentages. These samples underwent evaluation of tactile sensation, hardness, needle puncture, cut resistance, suture retention, defect repair, and tensile elasticity. Expert craniofacial surgeon evaluators provided focused qualitative feedback on selected top-performing samples for further assessment and statistical comparisons. An evaluation revealed surrogate characteristics that were satisfactory and exhibited good performance. Sample 977 exhibited the highest performance, and comparison with the original surrogate (sample 810) demonstrated significant improvements in critical areas, emphasizing the efficacy of the refined composition. The study identified a silicone composition that directly addresses the feedback received by our team's original silicone surrogate. The study underscores the delicate balance between biofidelity and practicality in surgical simulation. The need for ongoing refinement in surrogate materials is evident to optimize training experiences for early surgical learners.

Oral microbiome and its relationship with oral cancer

ABSTRACT

As the initial point for digestion, the balance of oral microorganisms plays an important role in maintaining local and systemic health. Oral dysbiosis, or an imbalance in the oral microbial community, may lead to the onset of various diseases. The presence or abnormal increase of microbes in the oral cavity has attracted significant attention due to its complicated relationship with oral cancer. Oral cancer can remodel microbial profiles by creating a more beneficial microenvironment for its progression. On the other hand, altered microbial profiles can promote tumorigenesis by evoking a complex inflammatory response and affecting host immunity. This review analyzes the oncogenic potential of oral microbiome alterations as a driver and biomarker. Additionally, a potentially therapeutic strategy via the reversal of the oral microbiome dysbiosis in oral cancers has been discussed.

Activity and levels of TNF-α, IL-6 and IL-8 in saliva of children and young adults with dental caries: a systematic review and meta-analysis

BACKGROUND

Cytokines play an important role in the immunopathogenesis of dental caries. A systematic review and meta-analysis was carried out with the following three objectives: 1)To deepen and discuss through a comprehensive analysis of the literature the effects of dental caries on the activity and levels of TNF-α, IL-6 and IL-8 in saliva of children and young adults, 2)To compare the levels of this cytokines in saliva of the exposure group (moderate-severe dental caries) with the control group (caries-free or mild dental caries), and 3)To determine whether the levels of these cytokines could be used as a complementary clinical diagnostic tool to assess the severity of dental caries.

METHODS

The protocol followed PRISMA and Cochrane guidelines and was registered in the Open Science Framework (OSF): https://doi.org/10.17605/OSF.IO/MF74V . A digital search was performed in PubMed/MEDLINE, Cochrane, Scopus, and Google Schoolar databases from February 15th, 2012, to January 13th, 2024. The methodological validity of the selected studies was assessed using Joanna Briggs Institute (JBI) tool. A meta-analysis was performed using a random-effects model to evaluate the association between dental caries/health, and the concentration of TNF-α, IL-6 and IL-8.

RESULTS

The search strategy provided a total of 126 articles, of which 15 investigations met the inclusion criteria. The total number of patients studied was 1,148, of which 743 represented the case/exposure group, and 405 represented the control group. The age of the patients ranged from 3 to 25 years. IL-6 was the most prevalent cytokine in the saliva of children and young adults with active dental caries. The meta-analysis revealed that there are significant differences between the levels of IL-6 and TNF-α in saliva of children with active dental caries compared to their control groups.

CONCLUSIONS

The findings suggest that IL-6 and TNF-α levels may have potential as complementary biomarkers for assessing dental caries severity. However, further research is needed to validate these findings in larger and more diverse populations before clinical application.

The effect of probiotics supplementation on cancer-treatment complications: a critical umbrella review of interventional meta-analyses

Cancer-related complications pose significant challenges in the management and treatment of patients with malignancies. Several meta-analyses have indicated improving effects of probiotics on cancer complications, while some studies have reported contentious findings. The purpose of the present study was to evaluate the efficacy of probiotics in addressing cancer complications, including diarrhea, mucositis, and infections, following chemotherapy, radiotherapy, and surgery. Relevant studies were searched in the PubMed, Scopus, Embase and Web of Science databases and Google Scholar up to September 2023. All meta-analyses addressing the effects of probiotics on all cancer treatments-induced complications including infection, diarrhea and oral mucositis were included. The pooled results were calculated using a random-effects model. Analyses of subgroups, sensitivity and publication bias were also conducted. The results revealed that the probiotics supplementation was effective on reduction of total cancer complications (OR:0.53; 95% CI: 0.44, 0.62, p < 0.001; I2=79.0%, p < 0.001), total infection rate (OR:0.47; 95%CI: 0.41, 0.52, p < 0.001; I2= 48.8%, p < 0.001); diarrhea (OR:0.50; 95%CI: 0.44, 0.57, p < 0.001; I2=44.4%, p = 0.023) and severe diarrhea (OR: 0.4; 95%CI: 0.27, 0.56, p < 0.001; I2=31.3%, p = 0.178), oral mucositis (OR: 0.76; 95%CI: 0.58, 0.94, p < 0.001; I2=95.5%, p < 0.001) and severe oral mucositis (OR:0.65, 95%CI: 0.58, 0.72 p < 0.001; I2=22.1%, p = 0.274). Multi strain probiotic (OR:0.49; 95%CI: 0.32, 0.65, p < 0.001; I2=90.7%, p < 0.001) were more efficacious than single strain (OR:0.73; 95%CI: 0.66, 0.81, p < 0.001; I2=0.00%, p = 0.786). The findings of the current umbrella meta-analysis provide strong evidence that probiotic supplementation can reduce cancer complications.

Phyllanthus emblica fruit extract alleviates halitosis and reduces the inflammatory response to oral bacteria

OBJECTIVE

To assess the efficacy of Phyllanthus emblica extract in alleviating halitosis and reducing the inflammatory response to halitosis-related bacteria.

METHODOLOGY

This investigation, using Phyllanthus emblica fruit extract (PE), involved four aspects. First, we evaluated the effect on growth and aggregation of halitosis-related bacteria, including Fusobacterium nucleatum, Porphyromonas gingivalis, and Solobacterium moorei, using a microdilution assay and scanning electron microscopy. Second, volatile sulfur compound (VSC) levels were measured on individuals with halitosis in randomized short-term (26 participants) and double-blind randomized long-term trials (18 participants in each group) after rinsing with PE for 3, 6, and 12 h, and 28 days. Third, we analyzed pro-inflammatory cytokine expression in TR146 cells using quantitative real-time PCR and enzyme-linked immunosorbent assays. Lastly, we assessed pro-inflammatory cytokine secretion and Toll-like receptor (TLR) 2 mRNA expression via the same experimental methods in a three-dimensional oral mucosal epithelial model (3D OMEM).

RESULTS

PE extract dose-dependently inhibited the growth of F. nucleatum (50% inhibition concentration [IC50]=0.079%), P. gingivalis (IC50=0.65%), and S. moorei (IC50=0.07%) and effectively prevented bacterial aggregation. Furthermore, VSC contents decreased significantly at 3, 6, and 12 h after rinsing with 5% PE compared with those in the control. Long-term use of mouthwash containing 5% PE for 28 days led to a significant decrease in VSC contents. PE attenuated the F. nucleatum- or P. gingivalis-stimulated mRNA expression and protein release of interleukin (IL)-6 and IL-8 in TR146 cells. It also suppressed IL-8 and prostaglandin E2 secretion and TLR2 mRNA expression in F. nucleatum-induced OMEMs.

CONCLUSION

Our findings support the use of PE in oral care products to alleviate halitosis and it may reduce inflammation.

Development of 3D gingival in vitro models using primary gingival cells

Since March 2013, animal testing for toxicity evaluation of cosmetic ingredients is banned in Europe. This directive applies to all personal care ingredients including oral ingredients. Gingival in vitro 3D models are commercially available. However, it is essential to develop "in house model" to modulate several parameters to study oral diseases, determine the toxicity of ingredients, test biocompatibility, and evaluate different formulations of cosmetic ingredients. Our expertise in tissue engineering allowed us to reconstruct human oral tissues from normal human gingival cells (fibroblasts and keratinocytes). Indeed, isolation from surgical leftover was performed to culture these gingival cells. These cells keep their endogenous capacity to proliferate allowing reconstruction of equivalent tissue close to in vivo tissue. Reconstruction of gingival epithelium, chorion equivalent, and the combination of these two tissues (full thickness) using primary gingival cells displayed all characteristics of an in vivo gingival model.

Periodontal inflammation as a potential driver of HIV low level viremia

HIV can be successfully suppressed to undetectable levels by antiretroviral therapy (ART) in most people with HIV (PWH). However, a small proportion continues to have persistent low-level viremia (LLV) during ART. A presumed source of LLV is production or replication from viral reservoirs, which are maintained in the presence of ART. It is unknown whether the oral cavity can be considered an HIV reservoir. As periodontal inflammation is a common problem in PWH, we hypothesize that periodontal inflammation in the oral cavity activates (latently) infected cells and thus might be associated with LLV. We included 11 individuals with HIV LLV, and compared HIV-RNA levels in saliva and plasma at baseline and at week 24 after switch of ART. We compared the LLV-group at baseline with 11 age-matched controls with suppressed viremia. To investigate the severity of periodontitis we used Periodontal Inflamed Surface Areas (PISA) by measuring probing depth, gingival recession, bleeding on probing and clinical attachment level. Severity of periodontitis was classified according to the CDC-AAP case definition. Additional insights in periodontal inflammation were obtained by comparing immune activation markers and the presence of periodontal pathogens. In four individuals of the LLV group, residual levels of HIV-RNA were detected in saliva at baseline (N = 1) or at week 24 (N = 2) or both (N = 1). Of the four individuals with LLV, three had residual levels of HIV-RNA in saliva. All 22 individuals had moderate to severe periodontitis. PISA was not significantly different between cases with LLV and controls. Similarly, periodontal pathogens were frequently observed in both groups. Total activated HLA-DR+CD38+ CD4+ cells and CD8+ cells were significantly higher in the LLV group than in the control group (p = <0.01). No immune markers were associated with LLV. In conclusion, periodontal inflammation is an unlikely driver of HIV LLV compared to HIV suppressed individuals.

Experimental models for peri-implant diseases: a narrative review

OBJECTIVES

Peri-implant diseases, being the most common implant-related complications, significantly impact the normal functioning and longevity of implants. Experimental models play a crucial role in discovering potential therapeutic approaches and elucidating the mechanisms of disease progression in peri-implant diseases. This narrative review comprehensively examines animal models and common modeling methods employed in peri-implant disease research and innovatively summarizes the in vitro models of peri-implant diseases.

MATERIALS AND METHODS

Articles published between 2015 and 2023 were retrieved from PubMed/Medline, Web of Science, and Embase. All studies focusing on experimental models of peri-implant diseases were included and carefully evaluated.

RESULTS

Various experimental models of peri-implantitis have different applications and advantages. The dog model is currently the most widely utilized animal model in peri-implant disease research, while rodent models have unique advantages in gene knockout and systemic disease induction. In vitro models of peri-implant diseases are also continuously evolving to meet different experimental purposes.

CONCLUSIONS

The utilization of experimental models helps simplify experiments, save time and resources, and promote advances in peri-implant disease research. Animal models have been proven valuable in the early stages of drug development, while technological advancements have brought about more predictive and relevant in vitro models.

CLINICAL RELEVANCE

This review provides clear and comprehensive model selection strategies for researchers in the field of peri-implant diseases, thereby enhancing understanding of disease pathogenesis and providing possibilities for developing new treatment strategies.

Biopolymer Drug Delivery Systems for Oromucosal Application: Recent Trends in Pharmaceutical R&D

Oromucosal drug delivery, both local and transmucosal (buccal), is an effective alternative to traditional oral and parenteral dosage forms because it increases drug bioavailability and reduces systemic drug toxicity. The oral mucosa has a good blood supply, which ensures that drug molecules enter the systemic circulation directly, avoiding drug metabolism during the first passage through the liver. At the same time, the mucosa has a number of barriers, including mucus, epithelium, enzymes, and immunocompetent cells, that are designed to prevent the entry of foreign substances into the body, which also complicates the absorption of drugs. The development of oromucosal drug delivery systems based on mucoadhesive biopolymers and their derivatives (especially thiolated and catecholated derivatives) is a promising strategy for the pharmaceutical development of safe and effective dosage forms. Solid, semi-solid and liquid pharmaceutical formulations based on biopolymers have several advantageous properties, such as prolonged residence time on the mucosa due to high mucoadhesion, unidirectional and modified drug release capabilities, and enhanced drug permeability. Biopolymers are non-toxic, biocompatible, biodegradable and may possess intrinsic bioactivity. A rational approach to the design of oromucosal delivery systems requires an understanding of both the anatomy/physiology of the oral mucosa and the physicochemical and biopharmaceutical properties of the drug molecule/biopolymer, as presented in this review. This review summarizes the advances in the pharmaceutical development of mucoadhesive oromucosal dosage forms (e.g., patches, buccal tablets, and hydrogel systems), including nanotechnology-based biopolymer nanoparticle delivery systems (e.g., solid lipid particles, liposomes, biopolymer polyelectrolyte particles, hybrid nanoparticles, etc.).

Advanced Immunomodulatory Biomaterials for Therapeutic Applications

The multifaceted biological defense system modulating complex immune responses against pathogens and foreign materials plays a critical role in tissue homeostasis and disease progression. Recently developed biomaterials that can specifically regulate immune responses, nanoparticles, graphene, and functional hydrogels have contributed to the advancement of tissue engineering as well as disease treatment. The interaction between innate and adaptive immunity, collectively determining immune responses, can be regulated by mechanobiological recognition and adaptation of immune cells to the extracellular microenvironment. Therefore, applying immunomodulation to tissue regeneration and cancer therapy involves manipulating the properties of biomaterials by tailoring their composition in the context of the immune system. This review provides a comprehensive overview of how the physicochemical attributes of biomaterials determine immune responses, focusing on the physical properties that influence innate and adaptive immunity. This review also underscores the critical aspect of biomaterial-based immune engineering for the development of novel therapeutics and emphasizes the importance of understanding the biomaterials-mediated immunological mechanisms and their role in modulating the immune system.

Altered oral microbiome, but normal human papilloma virus prevalence in cartilage-hair hypoplasia patients

BACKGROUND

Cartilage-hair hypoplasia (CHH) is a rare syndromic immunodeficiency with metaphyseal chondrodysplasia and increased risk of malignancy. In this cross-sectional observational study, we examined HPV status and oral microbiome in individuals with CHH. Oral brush samples were collected from 20 individuals with CHH (aged 5-59 years) and 41 controls (1-69 years). Alpha HPVs (43 types) were tested by nested PCR followed by bead-based probe hybridization. Separately, beta-, gamma-, mu- and nu- HPV types were investigated, and a genome-based bacterial microbiome sequencing was performed.

RESULTS

We found a similar alpha HPV prevalence in individuals with CHH (45%) and controls (36%). The HPV types of individuals with CHH were HPV-16 (25%), 27, 28, and 78, and of controls HPV-3, 16 (21%), 27, and 61. Beta HPV positivity and combined beta/gamma/mu/nu prevalence was detected in 11% and 11% of individuals with CHH and in 5% and 3% of the controls, respectively. Individuals with CHH differed from the controls in bacterial microbiota diversity, richness, and in microbial composition. Individuals with CHH had lower abundance of species Mitsuokella sp000469545, Parascardovia denticolens, Propionibacterium acidifaciens, UMGS1907 sp004151455, Salinicola halophilus, Haemophilus_A paraphrohaemolyticus, Fusobacterium massiliense, and Veillonella parvula, and higher abundance of Slackia exigua.

CONCLUSIONS

Individuals with CHH exhibit similar prevalence of HPV DNA but different bacterial microbiota on their oral mucosa compared to healthy controls. This may partly explain the previously observed high prevalence of oral diseases in CHH, and regular oral examination is warranted.

Emerging polymeric materials for treatment of oral diseases: design strategy towards a unique oral environment

Oral diseases are prevalent but challenging diseases owing to the highly movable and wet, microbial and inflammatory environment. Polymeric materials are regarded as one of the most promising biomaterials due to their good compatibility, facile preparation, and flexible design to obtain multifunctionality. Therefore, a variety of strategies have been employed to develop materials with improved therapeutic efficacy by overcoming physicobiological barriers in oral diseases. In this review, we summarize the design strategies of polymeric biomaterials for the treatment of oral diseases. First, we present the unique oral environment including highly movable and wet, microbial and inflammatory environment, which hinders the effective treatment of oral diseases. Second, a series of strategies for designing polymeric materials towards such a unique oral environment are highlighted. For example, multifunctional polymeric materials are armed with wet-adhesive, antimicrobial, and anti-inflammatory functions through advanced chemistry and nanotechnology to effectively treat oral diseases. These are achieved by designing wet-adhesive polymers modified with hydroxy, amine, quinone, and aldehyde groups to provide strong wet-adhesion through hydrogen and covalent bonding, and electrostatic and hydrophobic interactions, by developing antimicrobial polymers including cationic polymers, antimicrobial peptides, and antibiotic-conjugated polymers, and by synthesizing anti-inflammatory polymers with phenolic hydroxy and cysteine groups that function as immunomodulators and electron donors to reactive oxygen species to reduce inflammation. Third, various delivery systems with strong wet-adhesion and enhanced mucosa and biofilm penetration capabilities, such as nanoparticles, hydrogels, patches, and microneedles, are constructed for delivery of antibiotics, immunomodulators, and antioxidants to achieve therapeutic efficacy. Finally, we provide insights into challenges and future development of polymeric materials for oral diseases with promise for clinical translation.

Host-microbiome associations in saliva predict COVID-19 severity

Established evidence indicates that oral microbiota plays a crucial role in modulating host immune responses to viral infection. Following severe acute respiratory syndrome coronavirus 2, there are coordinated microbiome and inflammatory responses within the mucosal and systemic compartments that are unknown. The specific roles the oral microbiota and inflammatory cytokines play in the pathogenesis of coronavirus disease 2019 (COVID-19) are yet to be explored. Here, we evaluated the relationships between the salivary microbiome and host parameters in different groups of COVID-19 severity based on their oxygen requirement. Saliva and blood samples (n = 80) were collected from COVID-19 and from noninfected individuals. We characterized the oral microbiomes using 16S ribosomal RNA gene sequencing and evaluated saliva and serum cytokines and chemokines using multiplex analysis. Alpha diversity of the salivary microbial community was negatively associated with COVID-19 severity, while diversity increased with health. Integrated cytokine evaluations of saliva and serum showed that the oral host response was distinct from the systemic response. The hierarchical classification of COVID-19 status and respiratory severity using multiple modalities separately (i.e. microbiome, salivary cytokines, and systemic cytokines) and simultaneously (i.e. multimodal perturbation analyses) revealed that the microbiome perturbation analysis was the most informative for predicting COVID-19 status and severity, followed by the multimodal. Our findings suggest that oral microbiome and salivary cytokines may be predictive of COVID-19 status and severity, whereas atypical local mucosal immune suppression and systemic hyperinflammation provide new cues to understand the pathogenesis in immunologically compromised populations.

Modulation of myeloid-derived suppressor cell functions by oral inflammatory diseases and important oral pathogens

The oral cavity presents a diverse microbiota in a dynamic balance with the host. Disruption of the microbial community can promote dysregulation of local immune response which could generate oral diseases. Additionally, alterations in host immune system can result in inflammatory disorders. Different microorganisms have been associated with establishment and progression of the oral diseases. Oral cavity pathogens/diseases can modulate components of the inflammatory response. Myeloid-derived suppressor cells (MDSCs) own immunoregulatory functions and have been involved in different inflammatory conditions such as infectious processes, autoimmune diseases, and cancer. The aim of this review is to provide a comprehensive overview of generation, phenotypes, and biological functions of the MDSCs in oral inflammatory diseases. Also, it is addressed the biological aspects of MDSCs in presence of major oral pathogens. MDSCs have been mainly analyzed in periodontal disease and Sjögren's syndrome and could be involved in the outcome of these diseases. Studies including the participation of MDSCs in other important oral diseases are very scarce. Major oral bacterial and fungal pathogens can modulate expansion, subpopulations, recruitment, metabolism, immunosuppressive activity and osteoclastogenic potential of MDSCs. Moreover, MDSC plasticity is exhibited in presence of oral inflammatory diseases/oral pathogens and appears to be relevant in the disease progression and potentially useful in the searching of possible treatments. Further analyses of MDSCs in oral cavity context could allow to understand the contribution of these cells in the fine-tuned balance between host immune system and microorganism of the oral biofilm, as well as their involvement in the development of oral diseases when this balance is altered.

Using formalin fixed paraffin embedded tissue to characterize the microbiota in p16-positive and p16-negative tongue squamous cell carcinoma: a pilot study

BACKGROUND

Tongue squamous cell carcinoma (TSCC) is the most common oral cavity cancer, and p16 immunohistochemistry is an exact and available tool in the prognostic and predictive characterization of squamous cell cancers in the head and neck. Microorganisms have a close relationship with the development of TSCC. However, the association between oral bacteria and p16 status has not been well defined in the case of TSCC. Compared with traditional clinical microbial collection methods, formalin-fixed paraffin-embedded (FFPE) tissue samples have several advantages.

METHODS

To compare the microbiota compositions between p16-positive and p16-negative patients with TSCC, we performed a small pilot study of microbiological studies of TSCC by paraffin tissue. DNA from FFPE tissue blocks were extracted and microbiomes were profiled by sequencing the 16 S-rRNA-encoding gene (V1-V2/V3-V4/V4 regions). Alterations in the functional potential of the microbiome were predicted using PICRUSt, Tax4Fun, and BugBase.

RESULTS

A total of 60 patients with TSCC were enrolled in the study, however, some challenges associated with DNA damage in FFPE tissues existed, and only 27 (15 p16-positive and 12 p16-negative) passed DNA quality control. Nevertheless, we have tentatively found some meaningful results. The p16 status is associated with microbiota diversity, which is significantly increased in p16-positive patients compared with p16-negative patients. Desulfobacteria, Limnochordia, Phycisphaerae, Anaerolineae, Saccharimonadia and Kapabacteria had higher abundances among participants with p16-positive. Moreover, functional prediction revealed that the increase of these bacteria may enhance viral carcinogenesis in p16-positive TSCC.

CONCLUSIONS

Bacterial profiles showed a significant difference between p16-positive TSCC and p16-negative TSCC. These findings may provide insights into the relationship between p16 status and the microbial taxa in TSCC, and these bacteria may provide new clues for developing therapeutic targets for TSCC.

CCL28: A Promising Biomarker for Assessing Salivary Gland Functionality and Maintaining Healthy Oral Environments

The oral cavity serves as the primary path through which substances from the outside world enter our body. Therefore, it functions as a critical component of host defense. Saliva is essential for maintaining a stable oral environment by catching harmful agents, including pathogens, allergens, and chemicals, in the air or food. CCL28, highly expressed in mucosal tissues, such as the colon and salivary glands, is a chemokine that attracts CCR10/CCR3 expressing cells. However, the role of CCL28 in salivary gland formation remains unclear. In this study, we investigated the salivary gland structure in CCL28-deficient mice. Histological analysis showed decreased staining intensity of Alcian blue, which detects acidic mucous, reduced expression of MUC2, and higher infiltration of gram-positive bacteria in the salivary glands of CCL28-deficient mice. In addition, CCL28-deficient mice contained ectopically MUC2-expressed cells in the ducts and reduced the expression of cytokeratin 18, a marker for ductal cells, within the submandibular glands, resulting in decreased duct numbers. Additionally, the submandibular glands of CCL28-deficient mice showed reduced expression of several stem cell markers. These results suggest that CCL28 regulates saliva production via proper differentiation of salivary gland stem cells and could be a valuable biomarker of salivary gland function.

Validated WGS and WES protocols proved saliva-derived gDNA as an equivalent to blood-derived gDNA for clinical and population genomic analyses

BACKGROUND

Whole exome sequencing (WES) and whole genome sequencing (WGS) have become standard methods in human clinical diagnostics as well as in population genomics (POPGEN). Blood-derived genomic DNA (gDNA) is routinely used in the clinical environment. Conversely, many POPGEN studies and commercial tests benefit from easy saliva sampling. Here, we evaluated the quality of variant call sets and the level of genotype concordance of single nucleotide variants (SNVs) and small insertions and deletions (indels) for WES and WGS using paired blood- and saliva-derived gDNA isolates employing genomic reference-based validated protocols.

METHODS

The genomic reference standard Coriell NA12878 was repeatedly analyzed using optimized WES and WGS protocols, and data calls were compared with the truth dataset published by the Genome in a Bottle Consortium. gDNA was extracted from the paired blood and saliva samples of 10 participants and processed using the same protocols. A comparison of paired blood-saliva call sets was performed in the context of WGS and WES genomic reference-based technical validation results.

RESULTS

The quality pattern of called variants obtained from genomic-reference-based technical replicates correlates with data calls of paired blood-saliva-derived samples in all levels of tested examinations despite a higher rate of non-human contamination found in the saliva samples. The F1 score of 10 blood-to-saliva-derived comparisons ranged between 0.8030-0.9998 for SNVs and between 0.8883-0.9991 for small-indels in the case of the WGS protocol, and between 0.8643-0.999 for SNVs and between 0.7781-1.000 for small-indels in the case of the WES protocol.

CONCLUSION

Saliva may be considered an equivalent material to blood for genetic analysis for both WGS and WES under strict protocol conditions. The accuracy of sequencing metrics and variant-detection accuracy is not affected by choosing saliva as the gDNA source instead of blood but much more significantly by the genomic context, variant types, and the sequencing technology used.

Revolutionizing Brain Drug Delivery: Buccal Transferosomes on the Verge of a Breakthrough

The buccal cavity, also known as the oral cavity, is a complex anatomical structure that plays a crucial role in various physiological processes. It serves as a gateway to the digestive system and facilitates the initial stages of food digestion and absorption. However, its significance extends beyond mere digestion as it presents a promising route for drug delivery, particularly to the brain. Transferosomes are lipid-based vesicles that have gained significant attention in the field of drug delivery due to their unique structure and properties. These vesicles are composed of phospholipids that form bilayer structures capable of encapsulating both hydrophilic and lipophilic drugs. Strategies for the development of buccal transferosomes for brain delivery have emerged as promising avenues for pharmaceutical research. This review aims to explore the various approaches and challenges associated with harnessing the potential of buccal transferosomes as a means of enhancing drug delivery to the brain. By understanding the structure and function of both buccal tissue and transferosomes, researchers can develop effective formulation methods and characterization techniques to optimize drug delivery. Furthermore, strategic approaches and success stories in buccal transferosome development are highlighted, showcasing inspiring examples that demonstrate their potential to revolutionize brain delivery.

Medium-sized buccal mucosa defect reconstruction with buccal advancement flap in mucoepidermoid carcinoma ex pleomorphic adenoma: a case report

Introduction and importance

Mucoepidermoid carcinoma (MEC) ex pleomorphic adenoma is a rare type of salivary gland cancer. Surgical resection remains the standard therapy for this malignancy. After tumor removal, larger defects may require a local, regional, or free flap, while smaller ones can be closed primarily. Managing medium-sized defects can be challenging, especially on the buccal mucosa.

Presentation of case

A 47-year-old man had a buccal mucosa mass for 10 years, which gradually grew over a year and irritated his chewing. A 2.2×2 cm buccal mass was observed with telangiectatic and erythematous alterations in the surrounding mucosa. The preoperative tissue biopsy suggested salivary gland malignancy. The patient underwent surgical excision and a single-stage buccal advancement flap reconstruction, successfully closing the 4 cm defect. The final diagnosis was MEC ex pleomorphic adenoma. He reported mild discomfort during the first few months while opening his mouth. The patient had fully recovered after 6 months.

Clinical discussion

This is the first case of MEC arising in a pleomorphic adenoma of the buccal mucosa. For low-grade and small-sized tumors, a single modality is appropriate for treatment. Local flaps such as buccal fat pad or musculomucosal flap can repair medium-sized defects. However, the buccal advancement flap provides effective functional and esthetic benefits, optimal healing conditions, and reduces complications risk.

Conclusion

The buccal advancement flap is a valuable option for reconstructing medium-sized buccal defects up to 4 cm. The single-stage surgical procedure has been proven to yield minimal complications and provide a favorable outcome.

The Role of the Innate Immune Response in Oral Mucositis Pathogenesis

Oral mucositis (OM) is a significant complication of cancer therapy with limited management strategies. Whilst inflammation is a central feature of destructive and ultimately ulcerative pathology, to date, attempts to mitigate damage via this mechanism have proven limited. A relatively underexamined aspect of OM development is the contribution of elements of the innate immune system. In particular, the role played by barriers, pattern recognition systems, and microbial composition in early damage signaling requires further investigation. As such, this review highlights the innate immune response as a potential focus for research to better understand OM pathogenesis and development of interventions for patients treated with radiotherapy and chemotherapy. Future areas of evaluation include manipulation of microbial-mucosal interactions to alter cytotoxic sensitivity, use of germ-free models, and translation of innate immune-targeted agents interrogated for mucosal injury in other regions of the alimentary canal into OM-based clinical trials.

The Potential of Films as Transmucosal Drug Delivery Systems

Pharmaceutical films are polymeric formulations used as a delivery platform for administration of small and macromolecular drugs for local or systemic action. They can be produced by using synthetic, semi-synthetic, or natural polymers through solvent casting, electrospinning, hot-melt extrusion, and 3D printing methods, and depending on the components and the manufacturing methods used, the films allow the modulation of drug release. Moreover, they have advantages that have drawn interest in the development and evaluation of film application on the buccal, nasal, vaginal, and ocular mucosa. This review aims to provide an overview of and critically discuss the use of films as transmucosal drug delivery systems. For this, aspects such as the composition of these formulations, the theories of mucoadhesion, and the methods of production were deeply considered, and an analysis of the main transmucosal pathways for which there are examples of developed films was conducted. All of this allowed us to point out the most relevant characteristics and opportunities that deserve to be taken into account in the use of films as transmucosal drug delivery systems.

Oral mucosa immunity: ultimate strategy to stop spreading of pandemic viruses

Global pandemics are most likely initiated via zoonotic transmission to humans in which respiratory viruses infect airways with relevance to mucosal systems. Out of the known pandemics, five were initiated by respiratory viruses including current ongoing coronavirus disease 2019 (COVID-19). Striking progress in vaccine development and therapeutics has helped ameliorate the mortality and morbidity by infectious agents. Yet, organism replication and virus spread through mucosal tissues cannot be directly controlled by parenteral vaccines. A novel mitigation strategy is needed to elicit robust mucosal protection and broadly neutralizing activities to hamper virus entry mechanisms and inhibit transmission. This review focuses on the oral mucosa, which is a critical site of viral transmission and promising target to elicit sterile immunity. In addition to reviewing historic pandemics initiated by the zoonotic respiratory RNA viruses and the oral mucosal tissues, we discuss unique features of the oral immune responses. We address barriers and new prospects related to developing novel therapeutics to elicit protective immunity at the mucosal level to ultimately control transmission.

Engineering pedicled vascularized bladder tissue for functional bladder defect repair

An engineered bladder construct that mimics the structural and functional characteristics of native bladder is a promising therapeutic option for bladder substitution. We previously showed that pedicled vascularized smooth muscle tissue fabricated by grafting smooth muscle cell (SMC) sheets onto an axial capsule vascular bed had the potential for reliable bladder reconstruction. In this study, we investigated the feasibility of buccal mucosa graft (BMG) integration with the pedicled vascularized smooth muscle tissue to generate a full-layer pedicled vascularized bladder construct. BMG transplanted onto vascularized smooth muscle tissue showed good survival and developed into a pedicled vascularized bladder construct with full-layer structures, appropriate thickness, abundant vascularization, and effective barrier function. Then the full-thickness bladder defects were, respectively, reconstructed by pedicled capsule tissue (pedicled capsule group), nonpedicled vascularized bladder construct (nonpedicled construct group), and pedicled vascularized bladder construct (pedicled construct group). The picrosirius red (PSR) staining and immunohistochemistry results showed minimal fibrosis, maximal smooth muscle proportion, and high vascular density in the pedicled construct group. A continuous mucosal layer was observed only in the pedicled construct group. Moreover, morphological and functional studies revealed better bladder compliance and good ductility in the pedicled construct group. Overall, these results suggested that the BMG could be well integrated with vascularized smooth muscle tissue and generated a pedicled, fully vascularized, and structurally organized bladder construct, which facilitated structural remodeling and functional recovery and could become an alternative to bladder reconstruction.

Functional drug-delivery hydrogels for oral and maxillofacial wound healing

The repair process for oral and maxillofacial injuries involves hemostasis, inflammation, proliferation, and remodeling. Injury repair involves a variety of cells, including platelets, immune cells, fibroblasts, and various cytokines. Rapid and adequate healing of oral and maxillofacial trauma is a major concern to patients. Functional drug-delivery hydrogels play an active role in promoting wound healing and have shown unique advantages in wound dressings. Functional hydrogels promote wound healing through their adhesive, anti-inflammatory, antioxidant, antibacterial, hemostatic, angiogenic, and re-epithelialization-promoting properties, effectively sealing wounds and reducing inflammation. In addition, functional hydrogels can respond to changes in temperature, light, magnetic fields, pH, and reactive oxygen species to release drugs, enabling precise treatment. Furthermore, hydrogels can deliver various cargos that promote healing, including nucleic acids, cytokines, small-molecule drugs, stem cells, exosomes, and nanomaterials. Therefore, functional drug-delivery hydrogels have a positive impact on the healing of oral and maxillofacial injuries. This review describes the oral mucosal structure and healing process and summarizes the currently available responsive hydrogels used to promote wound healing.

Feline chronic gingivostomatitis current concepts in clinical management

PRACTICAL RELEVANCE

Feline chronic gingivostomatitis (FCGS) is a debilitating disease for cats and a challenge for veterinarians and cat caregivers alike. Recent literature indicates that the disease is immune-mediated in nature and likely associated with a chronic viral infection in patients with higher alpha diversity of their subgingival microbiome. The immune-mediated nature of FCGS includes both local as well as systemic effects, and the transcriptomic analysis of affected patients supports these findings.

TREATMENT OPTIONS

Localized therapy in the form of surgical extraction of all, or nearly all, teeth continues to be the mainstay of treatment. For cats that do not respond to surgical management, medical management, in the form of immunosuppressive or immunomodulatory therapy, remains an option. Analgesia is of fundamental importance. Immunomodulation utilizing mesenchymal stromal cell therapy provides an alternative treatment avenue for refractory patients and likely targets the chronic viral infection present in this disease. The potential for treatment stratification and use of novel systemic treatment options may be revealed as the molecular pathways involved in this disease are better described.

AIMS

This review outlines current and emerging concepts linking available science pertaining to FCGS and clinical management of the disease.

EVIDENCE BASE

The article draws on the best evidence base at this juncture and is also driven by the authors' collective experience of working on the disease for over a decade.

Targeting Th17 cells: a promising strategy to treat oral mucosal inflammatory diseases

With the improved quality of life, oral health is under increased pressure. Numerous common oral mucosal diseases, such as oral lichen planus(OLP) and gingivitis, are related to the destruction of the oral immune barrier. The cytokines secreted by T-helper 17 (Th17) cells are essential for maintaining oral immune homeostasis and play essential roles in immune surveillance. When antigens stimulate the epithelium, Th17 cells expand, differentiate, and generate inflammatory factors to recruit other lymphocytes, such as neutrophils, to clear the infection, which helps to maintain the integrity of the epithelial barrier. In contrast, excessive Th17/IL-17 axis reactions may cause autoimmune damage. Therefore, an in-depth understanding of the role of Th17 cells in oral mucosa may provide prospects for treating oral mucosal diseases. We reviewed the role of Th17 cells in various oral and skin mucosal systemic diseases with oral characteristics, and based on the findings of these reports, we emphasize that Th17 cellular response may be a critical factor in inflammatory diseases of the oral mucosa. In addition, we should pay attention to the role and relationship of "pathogenic Th17" and "non-pathogenic Th17" in oral mucosal diseases. We hope to provide a reference for Th17 cells as a potential therapeutic target for treating oral mucosal inflammatory disorders in the future.

AFM methods for studying the morphology and micromechanical properties of the membrane of human buccal epithelium cell

Using AFM methods in air under normal conditions in a wide range of local force effects ([Formula: see text]< 40 μN) the relief, functional micromechanical properties (elasticity coefficient [Formula: see text], Young's modulus [Formula: see text], elastic [Formula: see text] and plastic [Formula: see text] deformations) and adhesive properties (work [Formula: see text] of adhesive forces [Formula: see text]) of the membranes of living adult cells of human buccal epithelium were studied in the presence of a protective layer < 100 nm of buffer solution that prevented the cells from drying. Almost all geometric and functional characteristics of the membrane in the local approximation at the micro- and nanolevels are affected by size effects and obey the laws of fractal geometry. The Brownian multifractal relief of the membrane is characterized by dimension [Formula: see text] < 2.56 and irregularities < 500 nm vertically and < 2 μm horizontally. Its response to elastic (≤ 6 nN), active (6-21 nN), or passive (> 21 nN) stimulation ([Formula: see text]) is a non-trivial selective process and exhibits a correspondingly elastic ([Formula: see text] 67.4 N/m), active ([Formula: see text] 80.2 N/m) and passive ([Formula: see text] 84.5 N/m) responses. [Formula: see text] and [Formula: see text] depend on [Formula: see text]. Having undergone slight plastic deformations [Formula: see text] < 300 nm, the membrane is capable of restoring its shape. We mapped ([Formula: see text], [Formula: see text] = 2.56; [Formula: see text], [Formula: see text] = 2.68; [Formula: see text], [Formula: see text] = 2.42, [Formula: see text] and [Formula: see text]) indicating its complex cavernous structure.

From Pathogenesis to Intervention: The Importance of the Microbiome in Oral Mucositis

Oral mucositis (OM) is a common and impactful toxicity of standard cancer therapy, affecting up to 80% of patients. Its aetiology centres on the initial destruction of epithelial cells and the increase in inflammatory signals. These changes in the oral mucosa create a hostile environment for resident microbes, with oral infections co-occurring with OM, especially at sites of ulceration. Increasing evidence suggests that oral microbiome changes occur beyond opportunistic infection, with a growing appreciation for the potential role of the microbiome in OM development and severity. This review collects the latest articles indexed in the PubMed electronic database which analyse the bacterial shift through 16S rRNA gene sequencing methodology in cancer patients under treatment with oral mucositis. The aims are to assess whether changes in the oral and gut microbiome causally contribute to oral mucositis or if they are simply a consequence of the mucosal injury. Further, we explore the emerging role of a patient's microbial fingerprint in OM development and prediction. The maintenance of resident bacteria via microbial target therapy is under constant improvement and should be considered in the OM treatment.

Host-Microbiome Associations in Saliva Predict COVID-19 Severity

Established evidence indicates that oral microbiota plays a crucial role in modulating host immune responses to viral infection. Following Severe Acute Respiratory Syndrome Coronavirus 2 - SARS-CoV-2 - there are coordinated microbiome and inflammatory responses within the mucosal and systemic compartments that are unknown. The specific roles that the oral microbiota and inflammatory cytokines play in the pathogenesis of COVID-19 are yet to be explored. We evaluated the relationships between the salivary microbiome and host parameters in different groups of COVID-19 severity based on their Oxygen requirement. Saliva and blood samples (n = 80) were collected from COVID-19 and from non-infected individuals. We characterized the oral microbiomes using 16S ribosomal RNA gene sequencing and evaluated saliva and serum cytokines using Luminex multiplex analysis. Alpha diversity of the salivary microbial community was negatively associated with COVID-19 severity. Integrated cytokine evaluations of saliva and serum showed that the oral host response was distinct from the systemic response. The hierarchical classification of COVID-19 status and respiratory severity using multiple modalities separately (i.e., microbiome, salivary cytokines, and systemic cytokines) and simultaneously (i.e., multi-modal perturbation analyses) revealed that the microbiome perturbation analysis was the most informative for predicting COVID-19 status and severity, followed by the multi-modal. Our findings suggest that oral microbiome and salivary cytokines may be predictive of COVID-19 status and severity, whereas atypical local mucosal immune suppression and systemic hyperinflammation provide new cues to understand the pathogenesis in immunologically naïve populations.

ASCT2-mediated glutamine uptake of epithelial cells facilitates CCL5-induced T cell infiltration via ROS-STAT3 pathway in oral lichen planus

BACKGROUND

Oral lichen planus (OLP) is a chronic inflammatory disease characterized by T cell infiltration at lesion sites. T cell migration is greatly facilitated by chemokines produced by epithelial cells. Studies have noted the potential role of glutamine uptake in OLP and other inflammatory diseases. Here, we investigated the effect of altered glutamine uptake of epithelial cells on T cell infiltration and its underlying mechanisms in OLP.

METHODS

Immunohistochemistry was used to identify the expressions of glutamine transporter alanine-serine-cysteine transporter 2 (ASCT2) and C-C motif chemokine ligand 5 (CCL5) in oral tissues of OLP and healthy controls. Human gingival epithelial cells (HGECs) were treated with glutamine deprivation and ASCT2 inhibiter GPNA respectively to detect the expressions of CCL5 and its related signaling molecules. Additionally, we had determined the impact of epithelial cell-derived CCL5 on T-cell migration using a co-culture system in vitro.

RESULTS

ASCT2 and CCL5 expressions in OLP were significantly higher than healthy controls and positively correlated with the density of inflammatory infiltrations. Glutamine supplement significantly increased CCL5 production in HGECs, which was effectively inhibited by GPNA. Besides, glutamine could inhibit reactive oxygen species (ROS) production to activate the signal transducer and activator of transcription 3 (STAT3) causing higher expression level of CCL5 in HGECs. Simultaneously, T cell migration could be blocked by anti-CCL5 neutralizing antibody and STAT3 inhibitor stattic in the co-culture system.

CONCLUSION

The upregulated ASCT2-mediated glutamine uptake in epithelial cells promotes CCL5 production via ROS-STAT3 signaling, which boosts the T-cell infiltration in OLP lesion.

Assessment of Cytological Changes in the Oral Mucosa in Young Hematological Patients Treated with Systemic Chemotherapy

Background and Objectives: The primary objective of the undertaken study was to determine the morphological changes that occur within the oral epithelium in children undergoing chemotherapy following a diagnosis of hematological malignancies. Materials and Methods: The study group consisted of 18 patients diagnosed with leukemia or lymphoma undergoing treatment with chemotherapy. Swabs (liquid-based cytology) were collected from the oral cavity for microscopic evaluation at baseline, during the chemotherapy cycle with oral mucositis symptoms present, and upon completion of the cycle. Both the neutrophil count and oral mucositis (OM) were registered using the WHO (World Health Organization) scale. The control group included 41 children who were generally healthy. All samples underwent microscopical analyses at the Department of Pathology, Medical University of Gdansk, Poland. Results: A total of 190 cytological preparations were evaluated. The baseline preparations revealed similar cytological images, and the superficial cells of the epithelial layers were seen. A significant (p < 0.01) increase in the number of cells in the intermediate layer of the oral epithelium, as well as a decrease (p < 0.01) in the volume of cells in the superficial layers, was observed in further stages of cytostatic treatment. Conclusions: A decrease in the percentage of superficial epithelial cells with a corresponding increase in the number of intermediate epithelial cells is considered to be a result of toxic damage to the oral mucosa during chemotherapy.

Osteoimmunology in Periodontitis and Orthodontic Tooth Movement

PURPOSE OF REVIEW

To review the role of the immune cells and their interaction with cells found in gingiva, periodontal ligament, and bone that leads to net bone loss in periodontitis or bone remodeling in orthodontic tooth movement.

RECENT FINDINGS

Periodontal disease is one of the most common oral diseases causing inflammation in the soft and hard tissues of the periodontium and is initiated by bacteria that induce a host response. Although the innate and adaptive immune response function cooperatively to prevent bacterial dissemination, they also play a major role in gingival inflammation and destruction of the connective tissue, periodontal ligament, and alveolar bone characteristic of periodontitis. The inflammatory response is triggered by bacteria or their products that bind to pattern recognition receptors that induce transcription factor activity to stimulate cytokine and chemokine expression. Epithelial, fibroblast/stromal, and resident leukocytes play a key role in initiating the host response and contribute to periodontal disease. Single-cell RNA-seq (scRNA-seq) experiments have added new insight into the roles of various cell types in the response to bacterial challenge. This response is modified by systemic conditions such as diabetes and smoking. In contrast to periodontitis, orthodontic tooth movement (OTM) is a sterile inflammatory response induced by mechanical force. Orthodontic force application stimulates acute inflammatory responses in the periodontal ligament and alveolar bone stimulated by cytokines and chemokines that produce bone resorption on the compression side. On the tension side, orthodontic forces induce the production of osteogenic factors, stimulating new bone formation. A number of different cell types, cytokines, and signaling/pathways are involved in this complex process. Inflammatory and mechanical force-induced bone remodeling involves bone resorption and bone formation. The interaction of leukocytes with host stromal cells and osteoblastic cells plays a key role in both initiating the inflammatory events as well as inducing a cellular cascade that results in remodeling in orthodontic tooth movement or in tissue destruction in periodontitis.

Novel Double-Layer Dissolving Microneedles for Transmucosal Sequential Delivery of Multiple Drugs in the Treatment of Oral Mucosa Diseases

The development of transmucosal drug delivery systems is a practical requirement in oral clinical practice, and controlled sequential delivery of multiple drugs is usually required. On the basis of the previous successful construction of monolayer microneedles (MNs) for transmucosal drug delivery, we designed transmucosal double-layer sequential dissolving MNs using hyaluronic acid methacryloyl (HAMA), hyaluronic acid (HA), and polyvinyl pyrrolidone (PVP). MNs have the advantages of small size, easy operation, good strength, rapid dissolution, and one-time delivery of two drugs. Morphological test results showed that the HAMA-HA-PVP MNs were small and intact in structure. The mechanical strength and mucosal insertion test results indicated the HAMA-HA-PVP MNs had appropriate strength and could penetrate the mucosal cuticle quickly to achieve transmucosal drug delivery. The in vitro and in vivo experiment results of the double-layer fluorescent dyes simulating drug release revealed that MNs had good solubility and achieved stratified release of the model drugs. The results of the in vivo and in vitro biosafety tests also indicated that the HAMA-HA-PVP MNs were biosafe materials. The therapeutic effect of drug-loaded HAMA-HA-PVP MNs in the rat oral mucosal ulcer model demonstrated that these novel HAMA-HA-PVP MNs quickly penetrated the mucosa, dissolved and effectively released the drug, and achieved sequential drug delivery. Compared to monolayer MNs, these HAMA-HA-PVP MNs can be used as double-layer drug reservoirs for controlled release, effectively releasing the drug in the MN stratification by dissolution in the presence of moisture. The need for secondary or multiple injections can be avoided, thus improving patient compliance. This drug delivery system can serve as an efficient, multipermeable, mucosal, and needle-free alternative for biomedical applications.

Human β-Defensins in Diagnosis of Head and Neck Cancers

Head and neck cancers are malignant growths with high death rates, which makes the early diagnosis of the affected patients of utmost importance. Over 90% of oral cavity cancers come from squamous cells, and the tongue, oral cavity, and salivary glands are the most common locations for oral squamous cell carcinoma lesions. Human β-defensins (hBDs), which are mainly produced by epithelial cells, are cationic peptides with a wide antimicrobial spectrum. In addition to their role in antimicrobial defense, these peptides also take part in the regulation of the immune response. Recent studies produced evidence that these small antimicrobial peptides are related to the gene and protein expression profiles of tumors. While the suppression of hBDs is a common finding in head and neck cancer studies, opposite findings were also presented. In the present narrative review, the aim will be to discuss the changes in the hBD expression profile during the onset and progression of head and neck cancers. The final aim will be to discuss the use of hBDs as diagnostic markers of head and neck cancers.

Cytokines secreted by inflamed oral mucosa: implications for oral cancer progression

The oral mucosa has an essential role in protecting against physical, microbial, and chemical harm. Compromise of this barrier triggers a wound healing response. Key events in this response such as immune infiltration, re-epithelialization, and stroma remodeling are coordinated by cytokines that promote cellular migration, invasion, and proliferation. Cytokine-mediated cellular invasion and migration are also essential features in cancer dissemination. Therefore, exploration of cytokines that regulate each stage of oral wound healing will provide insights about cytokines that are exploited by oral squamous cell carcinoma (SCC) to promote tumor development and progression. This will aid in identifying potential therapeutic targets to constrain SCC recurrence and increase patient survival. In this review, we discuss cytokines that overlap in oral wounds and SCC, emphasizing how these cytokines promote cancer progression.