Oral Mucosal Epithelial Cells Research Articles

Progress in Transdifferentiation of Autologous Alternative Cell Sources into Corneal Epithelial Cells.

Corneal limbal epithelial stem cells (LESCs) play a crucial role in corneal epithelium regeneration. Severe damage to these cells can result in limbal stem cell deficiency (LSCD), characterized by repeated corneal conjunctivalization, leading to corneal turbidity and scar formation. Restoring functional LESCs and their ecological location are essential for treating LSCD. The goal of this review is to provide researchers and clinicians with key insights into LESCs biology and to conclude the current cell-based therapies advancement in LSCD treatments. Therapeutic cell resources mainly include mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), skin keratinocyte stem cells (SKCs), and oral mucosal epithelial cells (OMECs).

Surgical Technique for Oral Mucosa Harvesting in Autologous Cultivated Oral Mucosal Epithelial Cell Transplantation for Ocular Surface Disorders.

Ex vivocultivated oral mucosal epithelial cell transplantation (COMET) was first introduced in Japan in June 2021. This technique is used to treat limbal stem cell deficiency (LSCD). This article provides a detailed description of one of the most critical steps in COMET, which is the harvesting of oral mucosa, along with accompanying videos. The samples harvested using this method were successfully cultured into cell sheets, which were then used in surgical procedures without complications.

The immunobiology of corneal HSV-1 infection and herpetic stromal keratitis.

SUMMARYHuman alphaherpesvirus 1 (HSV-1) is a highly successful neurotropic pathogen that primarily infects the epithelial cells lining the orofacial mucosa. After primary lytic replication in the oral, ocular, and nasal mucosal epithelial cells, HSV-1 establishes life-long latency in neurons within the trigeminal ganglion. Patients with compromised immune systems experience frequent reactivation of HSV-1 from latency, leading to virus entry in the sensory neurons, followed by anterograde transport and lytic replication at the innervated mucosal epithelial surface. Although recurrent infection of the corneal mucosal surface is rare, it can result in a chronic immuno-inflammatory condition called herpetic stromal keratitis (HSK). HSK leads to gradual vision loss and can cause permanent blindness in severe untreated cases. Currently, there is no cure or successful vaccine to prevent latent or recurrent HSV-1 infections, posing a significant clinical challenge to managing HSK and preventing vision loss. The conventional clinical management of HSK primarily relies on anti-virals to suppress HSV-1 replication, anti-inflammatory drugs (such as corticosteroids) to provide symptomatic relief from pain and inflammation, and surgical interventions in more severe cases to replace damaged cornea. However, each clinical treatment strategy has limitations, such as local and systemic drug toxicities and the emergence of anti-viral-resistant HSV-1 strains. In this review, we summarize the factors and immune cells involved in HSK pathogenesis and highlight alternate therapeutic strategies for successful clinical management of HSK. We also discuss the therapeutic potential of immunoregulatory cytokines and immunometabolism modulators as promising HSK therapies against emerging anti-viral-resistant HSV-1 strains.

The mechanism of low molecular weight fucoidan-incorporated nanofiber scaffolds inhibiting oral leukoplakia via SR-A/Wnt signal axis.

Oral leukoplakia (OLK) is the most common oral precancerous lesion, and 3%-17% of OLK patients progress to oral squamous cell carcinoma. OLK is susceptible to recurrence and has no effective treatment. However, conventional drugs have significant side effects and limitations. Therefore, it is important to identify drugs that target OLK. In this study, scavenger receptor A (SR-A) was found to be abnormally highly expressed in the oral mucosal epithelial cells of OLK patients, whereas molecular biology studies revealed that low molecular weight fucoidan (LMWF) promoted apoptosis of dysplastic oral keratinocytes (DOK) and inhibited the growth and migration of DOK, and the inhibitory effect of LMWF on OLK was achieved by regulating the SR-A/Wnt signaling axis and related genes. Based on the above results and the special situation of the oral environment, we constructed LMWF/poly(caprolactone-co-lactide) nanofiber membranes with different structures for the in-situ treatment of OLK using electrospinning technology. The results showed that the nanofiber membranes with a shell-core structure had the best physicochemical properties, biocompatibility, and therapeutic effect, which optimized the LMWF drug delivery and ensured the effective concentration of the drug at the target point, thus achieving precise treatment of local lesions in the oral cavity. This has potential application value in inhibiting the development of OLK.

Long-term prognosis and DNA damage status after oral mucosal epithelial cell sheet transplantation following esophageal endoscopic submucosal dissection for squamous cell carcinoma: A case series

Autologous oral mucosal epithelial cell sheet (AOMECS) transplantation has recently been applied in human patients to prevent postprocedural stenosis following endoscopic submucosal dissection (ESD) for esophageal squamous cell carcinoma. However, the long-term safety of AOMECS transplantation remains unclear. We evaluated the long-term outcomes of 10 patients who participated in a clinical trial of AOMECS transplantation after esophageal ESD. Additionally, we assessed the local DNA damage response in the esophageal epithelium using p53 binding protein 1 (53BP1) immunofluorescence in post-AOMECS biopsy specimens. The median follow-up period was 118.5 months (range: 46–130 months). Two patients developed primary esophageal cancer near the AOMECS site and successfully underwent additional ESD. One patient developed lymph node metastasis and underwent chemotherapy. None of the patients died from the original disease, although one patient died from unrelated causes. The rate of abnormal 53BP1 nuclear foci, indicative of increased genome instability, increased with the progression of neoplasia in patients post AOMECS. Our case series suggests that AOMECS transplantation provides an acceptable long-term prognosis and 53BP1 foci may serve as a useful marker for assessing DNA instability in the post-AOMECS esophageal epithelium.

Identification of activating transcription factor 6 (ATF6) as a novel prognostic biomarker and potential target in oral squamous cell carcinoma

BackgroundOral squamous cell carcinoma (OSCC) is originating from oral mucosal epithelial cells. Autophagy plays a crucial role in cancer treatment by promoting cellular self-degradation and eliminating damaged components, thereby enhancing therapeutic efficacy. In this study, we aim to identify a novel autophagy-related biomarker to improve OSCC therapy. MethodsWe firstly utilized Cox and Lasso analyses to identify that ATF6 is associated with OSCC prognosis, and validated the results by Kaplan-Meier survival analysis. We further identified the downstream pathways and related genes by enrichment analysis and WGCNA analysis. Subsequently, we used short interfering RNA to investigate the effects of ATF6 knockdown on proliferation, migration, apoptosis, and autophagy in SCC-9 and SCC-15 cells through cell viability assay, transwell assay, EdU incorporation assay, flow cytometry analysis, western blot analysis and immunofluorescence analysis, etc. ResultsBioinformatics analyses showed that ATF6 overexpression was associated with prognosis and detrimental to survival. In vitro studies verified that ATF6 knockdown reduced OSCC cell proliferation and migration. Mechanistically, ATF6 knockdown could promote cellular autophagy and apoptosis. ConclusionWe propose that ATF6 holds potential as a prognostic biomarker linked to autophagy in OSCC. This study provides valuable clues for further exploration of targeted therapy against OSCC.

Lessons learned from contamination with endotoxin originated from the supplement in the cell culture medium

IntroductionEndotoxin is a typical pyrogen derived from the outer membrane of Gram-negative bacteria. In fabricating cell-based medicinal products, it is necessary to control endotoxin in the process and the products. In the quality control tests of our clinical study, endotoxin concentration in the culture supernatant of autologous oral mucosal epithelial cell sheets exceeded the criterion value. Therefore, endotoxin measurements were conducted to clarify the cause of the endotoxin contamination. MethodsThe reagents used to prepare the culture medium, the unused culture medium, and the culture supernatants were diluted with pure water. Endotoxin concentrations in the diluted samples were measured. ResultsEndotoxin was detected in both the unused culture medium and the culture supernatant of the epithelial cell sheets at higher concentrations than the criterion value. Therefore, endotoxin concentrations in the reagents used to prepare the culture medium were measured and were found to be below the criterion value, except for cholera toxin. On the other hand, three lots of cholera toxin products were used for the measurement, and the endotoxin concentrations were higher than the criterion value. The results indicate that the endotoxin contamination is caused by the cholera toxin product. ConclusionsTo prevent endotoxin contamination in cell-based medicinal products, endotoxin concentrations in reagents used for the fabrication should be measured in the facility conducting clinical research or confirmed by an adequate certificate of analysis from the manufacturers of the reagents.

Effect of sub-minimum inhibitory concentrations of ceftriaxone on the Pseudomonas aeruginosa adhesion to human oral mucosal epithelial cells and biofilm formation to polystyrene in vitro

Effect of sub-minimum inhibitory concentrations of ceftriaxone on the Pseudomonas aeruginosa adhesion to human oral mucosal epithelial cells and biofilm formation to polystyrene in vitro

Cytomorphometric analysis of buccal mucosal cells in iron deficiency anemia: A cross-sectional study.

Worldwide, at any given moment, more individuals have iron deficiency anemia (IDA) than any other health problems. Very few studies have been conducted to evaluate changes in oral mucosa in IDA. The present study is undertaken for cytomorphometric analysis of buccal mucosal cells in IDA. Nuclear diameter (ND), cell diameter (CD), nuclear area (NA), cell area (CA), and nuclear-cytoplasmic ratio (N/C) are measured and compared in buccal mucosal cells of IDA patients and controls. To evaluate cytomorphometric changes in epithelial cells of oral mucosa in IDA and to compare these changes with the controls. A cross-sectional study. Forty cases of IDA and forty cases of control group were selected for the study. IDA cases were diagnosed with decreased Hb level, MCV, MCH, MCHC and confirmed by decreased serum iron and increased total iron-binding capacity levels. Cytomorphometric analysis of buccal mucosa was performed to study CA, CD, NA, ND, and N/C ratio. Statistical analysis was done using t- test in SPSS software version 4. Results of our study showed increased cell area, cell diameter, nuclear area, nuclear diameter, and nuclear-cytoplasmic ratio in anemic group as compared to controls. The study suggests that individuals with IDA regardless of clinically visible oral lesions show cytological changes in oral mucosal epithelium. Knowledge of quantitative alterations in oral epithelial cells of IDA patients is important as these alterations are similar to those seen in precancerous and radiation-induced changes. Cytomorphometry is an efficient tool to understand the extent of cellular changes that occur in oral epithelial cells in IDA.

Fibrotic Matrix Induces Mesenchymal Transformation of Epithelial Cells in Oral Submucous Fibrosis

Oral submucous fibrosis (OSF) is a potentially malignant disorder of the oral mucosa; however, whether and how the fibrotic matrix of OSF is involved in the malignant transformation of epithelial cells remains unknown. Herein, oral mucosa tissue from patients with OSF, OSF rat models, and their controls were used to observe the extracellular matrix changes and epithelial-mesenchymal transformation (EMT) in fibrotic lesions. Compared with controls, oral mucous tissues from patients with OSF showed an increased number of myofibroblasts, a decreased number of blood vessels, and increased type I and type III collagen levels. In addition, the oral mucous tissues from humans and OSF rats showed increased stiffness, accompanied by increased EMT activities of epithelial cells. The EMT activities of stiff construct-cultured epithelial cells were increased significantly by exogenous piezo-type mechanosensitive ion channel component 1 (Piezo1) activation, and decreased by yes-associated protein (YAP) inhibition. During exvivo implantation, oral mucosal epithelial cells of the stiff group showed increased EMT activities and increased levels of Piezo1 and YAP compared with those in the sham and soft groups. These results indicate that increased stiffness of the fibrotic matrix in OSF led to increased proliferation and EMT of mucosal epithelial cells, in which the Piezo1-YAP signal transduction is important.

Description of Candida albicans Fungus in The Oral Mucosa of Patients With Fe Deficiency Anemia in RSUD Ciamis

Background & Objective Indonesia is a developing country where Fe deficiency anemia is common. Fe deficiency anemia is a malnutrition disease caused by a lack of Fe in the patient's body. Fe deficiency anemia is triggered by a lack of Fe in the body for the formation of hemoglobin, causing patients to experience blood deficiency and thinning of oral mucosal epithelial cells which can cause oral candidiasis. Analyzing the description of oral candidiasis in patients with Fe deficiency anemia. Methods This study is a descriptive study that recruited a total sampling of 17 patients with Fe deficiency anemia. Oral candidiasis in Fe deficiency anemia was measured by planting on sabouraud dextrose agar (SDA) media and sugars media then observed macroscopically and microscopically from SDA and sugars cultures using a microscope. Results Based on the results of the study, 15 (88%) positive respondents and 2 (12%) negative respondents. Conclusion The results of the examination of oral candidiasis as many as 15 samples were affected by oral candidiasis caused by Candida albicans.

Association of Prevotella intermedia with oropharyngeal cancer: A patient-control study

ObjectiveTo investigate the frequencies and bacterial load of three species of periodontal bacteria in samples from oropharyngeal cancer patients versus healthy individuals. Study designThis is a case-control study based on biopsies collected from tumor tissues obtained from patients with oropharyngeal squamous cell carcinoma between 2016 and 2017 and shed oral mucosal epithelial cells that were collected from controls using the Cepimax® brush, carrying out several brushings towards the posterior third edge of the tongue and the cheek. Porphyromonas gingivalis, Tannerella forsythia and Prevotella intermedia detection and absolute quantification was determined through q-PCR. Statistical analysis included a U- test, X2, Fisher's exact test, odds ratio (OR) and Conditional logistic regression analysis and unconditional regression analysis (p < 0.05). ResultsA total of 48 donors older than 55 years old participated in this study. The population was distributed into 24 patients (cases) and 24 controls. A robust association was established in cases and controls with significance regarding Prevotella intermedia (OR: 15.00) and Porphyromonas gingivalis (OR:11.00). In the comparison between the amount of each bacteria in the groups, P. intermedia showed a higher bacterial load in oropharyngeal cancer patients (p = 0.04). However, multivariate analysis adjusted to the presence of different bacteria and the diverse confounding variables did not reveal significant differences for oropharyngeal cancer association. ConclusionP. gingivalis and P. intermedia were detected more frequently in the group of patients with cancer. The bivariate analysis of the bacterial load evidenced significant differences for Prevotella intermedia, suggesting that it could be associated with oropharyngeal cancer.

CommerciallyA novel cultivated oral mucosal epithelial cell sheet transplantation (COMET) method using a commercially available regenerative product sheet originating from human ectopic autologous tissue

commerciallyA novel cultivated oral mucosal epithelial cell sheet transplantation (COMET) method using a commercially available regenerative product sheet originating from human ectopic autologous tissue

Thrombospondin-1 induction and VEGF reduction by proteasome inhibition

The present study focuses on investigating the expression of thrombospondin-1 (TSP-1), a natural inhibitor of neovascularization. Immunofluorescent staining was used to detect the expression of TSP-1 in rabbit corneal tissue with vascularization induced by limbectomy. TSP-1 was detected in healthy and Cultured Autologous Oral Mucosal Epithelial Cell Sheet (CAOMECS) grafted rabbit corneas. TSP-1 was not detected in diseased corneas. Rabbit and human primary oral mucosal and corneal epithelial cells were cultured and treated with proteasome inhibitor (PI) in vitro. Changes in the expression of TSP-1, HIF-1 alpha and 2 alpha, VEGF-A, and VEGF receptor were analyzed by Western blotting. Neovascularization developed in rabbits’ corneas as early as 1 month after limbectomy and was stable for at least 3 months. HIF-1 alpha and VEGF-A expression was reduced in CAOMECS grafted corneas, as compared to sham corneas. While TSP-1 expression was decreased in injured corneas, it was expressed in CAOMECS grafted corneas, but still less expressed compared to healthy corneas. PI treatment, of human oral mucosal and corneal epithelial cells increased TSP-1 expression and reduced VEGF-A expression. The results showed that TSP-1 expression was lost in injured corneal surface and that CAOMECS grafting restored TSP-1 expression to certain extent. Proteasome inhibition treatment increased TSP-1 and decreased VEGF-A expression in human oral mucosal and corneal epithelial cells. The result suggests that corneal neovascularization could be managed with the inhibition of the proteasome after CAOMECS grafting and increase corneal transparency.

Long-term outcomes of regenerative treatment by endoscopic oral mucosal epithelial cell sheet transplantation for the prevention of esophageal stricture after endoscopic resection

IntroductionWe reported the short-term outcomes of a regenerative medical treatment to prevent esophageal stricture after endoscopic submucosal dissection (ESD) using cultured tis oral mucosal epithelial cell sheets. This study investigated the long-term outcomes of this treatment. MethodsEpithelial cells, isolated from the patient's own oral mucosal tissue, were cultured for 16 days using temperature-responsive culture dishes. Then, the autologous cell sheets were endoscopically transplanted onto the bed of the esophageal ulcer after endoscopic mucosal resection (EMR) and ESD. Results of 10 patients who underwent endoscopic transplantation of oral mucosal epithelial cell sheets from April 2008 through February 2022 were recorded. We analyzed the outcome, the cause, and the endoscopic findings. ResultsThe median period of observation was 3761 days. No stricture was detected in any of the patients long-term. Two patients died because of pancreatic cancer and brainstem hemorrhage. One patient underwent chemo-radiotherapy for further treatment. The patients underwent surgery due to metastasis to the lymph nodes. Only the lymph nodes were dissected, and the esophagus remained intact. From the endoscopic findings: Melanosis was found at the transplanted site in a patient. Strong iodine staining was shown at the transplanted site in a patient. Transplantation of cultured oral mucosal epithelial cell sheets to prevent esophageal stricture has been proven to be a safe treatment. All patients showed no controlled esophageal stricture in the long term.

Expression of K-19 Cytokeratin in Gingival Epithelial Cells in Periodontal Health and Disease - An Immunohistochemical Study

Background and aim: CK19, a secondary keratin of simple epithelial cells, is the smallest cytokeratin. Its expression was observed in basal and suprabasal stratified squamous epithelial cells of oral mucosa, especially in case of inflammatory conditions and epithelial dysplasia. The aim of this analytical cross-sectional study was to investigate the expression of CK 19 in the gingival epithelial cells of healthy and periodontitis subjects and to correlate the findings with the clinical parameters. Materials and methods: The tissue samples were collected from a total of 30 patients from the healthy and periodontitis groups, during orthodontic/ 3rd molar extractions and during periodontal surgeries respectively. The tissues were then processed for immunohistochemistry analysis and the results were obtained. Results: The data obtained were statistically analysed (CHI square and ANOVA tests) and the results suggested that, there was no statistically significant difference in the expression of CK-19 between healthy and periodontitis groups. Conclusion: The results of this study further affirm the varied responses to destruction (breakdown and repair) from individual to individual during the host-microbial interactions. The mixed outcome could also be due to the suppression of overt inflammation following phase I therapy. Keywords: basal layers, cytokeratin, immunohistochemistry, inflammation, oral epithelium.

Prevention of Esophageal Stricture After Whole Circumferential Endoscopic Resection: A Review for Endoscopists.

The incidence of esophageal stricture without stricture prophylaxis measures after whole circumferential endoscopic resection is almost 100%, which substantially decreases the patients' quality of life and requires multiple sessions of endoscopic balloon dilation. To date, there are many reports concerning the prevention of esophageal stricture after whole circumferential endoscopic resection. Oral steroid may be effective for preventing esophageal stricture after whole circumferential endoscopic resection. However, exposure to a high dose of steroid raises concerns with regard to adverse events. Intralesional triamcinolone acetonide injection and preventive endoscopic balloon dilation did not appear to reduce the frequency of stricture formation after whole circumferential endoscopic resection. Esophageal stent appeared to be a possible prophylactic treatment, but adverse events should be of great concern. Polyglycolic acid sheets seemed promising, because they can not only act as protective barriers but can also be drug carriers to prevent esophageal stricture. Tissue engineering and regenerative medicine such as oral mucosal epithelial cell sheets cultured in vitro have been used in patients to prevent esophageal stricture, but it is technically and financially burdensome. Autologous tissue transplantation showed a promising preventive effect for esophageal stricture and it is relatively easy to carry out in clinical practice, and this technique needs further improvements to prevent esophageal stricture after whole circumferential endoscopic resection.

COVID-19 and oral cancer: Critical viewpoint.

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has marked the beginning of a new pandemic named coronavirus disease 2019 (COVID-19). The World Health Organization has announced it as a health emergency that is of international concern. The disease has been reported to cause respiratory illness, pneumonia and even hinder the immunity of an individual. Individuals with disturbed immune responses have been found to be quite susceptible to this viral infection. Oral cancer patients are also at high risk in this pandemic situation and might encounter severe detrimental outcomes. Angiotensin receptors, documented in studies as the path of entry of this virus, are highly expressed in the epithelial cells of oral mucosa, making the group of individuals with oral cancers even more vulnerable. Extracellular matrix metalloproteinase inducer is another potential target for SARS-CoV-2. An exhaustion of angiotensin converting enzyme 2 cell receptors leads to protumoral effects, whereas a downregulation of extracellular matrix metalloproteinase inducer leads to antitumoral effects. Thus, it causes a variation of the biological behavior of the tumor. This article focusses on the molecular mechanisms, effects and patho-physiology of COVID-19 in oral squamous cell carcinoma patients. The different molecular changes in oral squamous cell carcinoma in the background of COVID-19 will modify various environmental factors for this pathology and have an effect on the carcinogenesis process. Understanding the behavior of the tumor will help plan advanced treatment strategies for oral squamous cell carcinoma patients in the background of COVID-19.

Human Umbilical Cord Lining-Derived Epithelial Cells: A Potential Source of Non-Native Epithelial Cells That Accelerate Healing in a Porcine Cutaneous Wound Model.

Human umbilical cord lining epithelial cells [CLECs) are naïve in nature and can be ethically recovered from cords that are routinely discarded. The success of using oral mucosal epithelial cells for cornea defects hints at the feasibility of treating cutaneous wounds using non-native CLECs. Herein, we characterized CLECs using flow cytometry (FC) and skin organotypic cultures in direct comparison with skin keratinocytes (KCs). This was followed by wound healing study to compare the effects of CLEC application and the traditional use of human skin allografts (HSGs) in a porcine wound model. While CLECs were found to express all the epidermal cell markers probed, the major difference between CLECs and KCs lies in the level of expression (in FC analysis) as well as in the location of expression (of the epithelium in organotypic cultures) of some of the basal cell markers probed. On the pig wounds, CLEC application promoted accelerated healing with no adverse reaction compared to HSG use. Though CLECs, like HSGs, elicited high levels of local and systemic immune responses in the animals during the first week, these effects were tapered off more quickly in the CLEC-treated group. Overall, the in vivo porcine data point to the potential of CLECs as a non-native and safe source of cells to treat cutaneous wounds.

Antimicrobial Effect of Extracellular Vesicles Derived From Human Oral Mucosal Epithelial Cells on Candida albicans.

Candida albicans (C. albicans) is a commensal microorganism that colonizes the mucosal surfaces of healthy individuals. Changes in the host or environment can lead to overgrowth of C. albicans and infection of the host. Extracellular vesicles (EVs) are released by almost all cell types and play an increasingly recognized role in fighting microbial infection. The aim of the present study was to assess whether EVs derived from human oral mucosal epithelial (Leuk-1) cells can suppress the growth and invasion of C. albicans. The in vitro efficacy of Leuk-1-EVs against C. albicans was assessed by optical microscopy, laser scanning confocal microscopy, scanning electron microscopy, and transmission electron microscopy. The germ tube formation rate, the percentage of hyphae and the microcolony optical density were also used to analyze the growth of C. albicans in a coculture model with Leuk-1 cells and EVs or after inhibition of the secretion of EVs. A mouse model of oral candidiasis was established and submucosal injection of Leuk-1-EVs in the tongue was performed. Macroscopic observation, H&E staining, PAS staining, and scanning electron microscopy were used to assess antifungal effects of Leuk-1-EVs in vivo. The in vitro results showed that the growth of C. albicans was inhibited and that the morphology and ultrastructure were changed following Leuk-1-EVs treatment. The in vivo results exhibited that white lesions of the tongue, C. albicans infection, and oral mucosal inflammation of the infected mice were significantly alleviated after Leuk-1-EVs treatment. We thus reveal an antifungal capability of EVs derived from oral epithelial cells against C. albicans that is mediated by direct damage effects and potential synergy between EVs and human oral mucosal epithelial cells. This finding offers an intriguing, previously overlooked method of antifungal defense against C. albicans.