Differential genotypes of TNF-α and IL-10 for immunological diagnosis in discoid lupus erythematosus and oral lichen planus: A narrative review.

Discoid lupus erythematosus and oral lichen planus are chronic systemic immune system-mediated diseases with unclear etiology and pathogenesis. The oral mucosa is the common primary site of pathogenesis in both, whereby innate and adaptive immunity and inflammation play crucial roles. The clinical manifestations of discoid lupus erythematosus on the oral mucosa are very similar to those of oral lichen planus; therefore, its oral lesion is classified under oral lichenoid lesions. In practice, the differential diagnosis of discoid lupus erythematosus and oral lichen planus has always relied on the clinical manifestations, with histopathological examination as an auxiliary diagnostic tool. However, the close resemblance of the clinical manifestations and histopathology proves challenging for accurate differential diagnosis and further treatment. In most cases, dentists and pathologists fail to distinguish between the conditions during the early stages of the lesions. It should be noted that both are considered to be precancerous conditions, highlighting the significance of early diagnosis and treatment. In the context of unknown etiology and pathogenesis, we suggest a serological and genetic diagnostic method based on TNF-α and IL-10. These are the two most common cytokines produced by the innate and adaptive immune systems and they play a fundamental role in maintaining immune homeostasis and modulating inflammation. The prominent variability in their expression levels and gene polymorphism typing in different lesions compensates for the low specificity of current conventional diagnostic protocols. This new diagnostic scheme, starting from the immunity and inflammation of the oral mucosa, enables simultaneous comparison of discoid lupus erythematosus and oral lichen planus. With relevant supportive evidence, this information can enhance physicians' understanding of the two diseases, contribute to precision medicine, and aid in prevention of precancerous conditions.

Expression Profiles of GILZ and Annexin A1 in Human Oral Candidiasis and Lichen Planus.

Adrenal glands are the major source of glucocorticoids, but recent studies indicate tissue-specific production of cortisol, including that in the oral mucosa. Both endogenous and exogenous glucocorticoids regulate the production of several proteins, including the glucocorticoid-induced leucine zipper (GILZ) and Annexin A1, which play important roles in the regulation of immune and inflammatory responses. Common inflammation-associated oral conditions include lichen planus and candidiasis, but the status of GILZ and Annexin A1 in these human conditions remains to be established. Accordingly, archived paraffin-embedded biopsy samples were subjected to immunohistochemistry to establish tissue localization and profile of GILZ and Annexin A1 coupled with the use of hematoxylin-eosin stain for histopathological assessment; for comparison, fibroma specimens served as controls. Histopathological examination confirmed the presence of spores and pseudohyphae for oral candidiasis (OC) specimens and marked inflammatory cell infiltrates for both OC and oral lichen planus (OLP) specimens compared to control specimens. All specimens displayed consistent and prominent nuclear staining for GILZ throughout the full thickness of the epithelium and, to varying extent, for inflammatory infiltrates and stromal cells. On the other hand, a heterogeneous pattern of nuclear, cytoplasmic, and cell membrane staining was observed for Annexin A1 for all specimens in the suprabasal layers of epithelium and, to varying extent, for inflammatory and stromal cells. Semi-quantitative analyses indicated generally similar fractional areas of staining for both GILZ and Annexin A1 among the groups, but normalized staining for GILZ, but not Annexin A1, was reduced for OC and OLP compared to the control specimens. Thus, while the cellular expression pattern of GILZ and Annexin A1 does not differentiate among these conditions, differential cellular profiles for GILZ vs. Annexin A1 are suggestive of their distinct physiological functions in the oral mucosa.

Identification of Potential Key Biomarkers and Immune Infiltration in Oral Lichen Planus.

Background: Oral lichen planus (OLP) is a chronic autoimmune oral mucosal disease that seriously affects the life quality of the patients. But till now, the exact etiology and pathogenesis of OLP remain unclear. Our study is aimed at finding the key molecules and pathways involved in the pathogenesis mechanisms of OLP, providing more effective therapeutic strategies for OLP. Methods: Data from GSE52130 were downloaded from GEO datasets for analysis. Then, we carried out enrichment analysis of the differentially expressed genes (DEGs) using Gene Ontology (GO) and KEGG pathway analyses. Next, the CIBERSORT algorithm was used to assess immune cell infiltration in OLP patients. Furthermore, we also constructed a protein-protein interaction network using STRING and Cytoscape and simultaneously sought potential transcription factors plug-in including MCODE CytoHubba and iRegulon. In addition, ROC analysis was employed to assess the diagnostic performance of these hub genes. Lastly, we identified 6 promising novel drugs to treat OLP through Connectivity Map. Results: We illustrated that 255 DEGs were mainly enriched in the focal adhesion pathway and metabolism pathways. Besides, Cibersort analysis showed that M1 macrophages, T follicular helper cells, and T regulatory cells are more infiltrated in OLP samples. In addition, ROC analysis demonstrated that these hub genes owned higher diagnostic value in OLP, in which SPRR1B had the highest diagnostic value. And we also predicted that SOX7 was the most relevant transcription factor of those hub genes. Lastly, through the CMap database, we identified 6 small molecules as possible treatment drugs of OLP. Conclusion: Our research identified that SPRR1B could be used as potential biomarkers for the early diagnosis of OLP. In addition, as a chronic autoimmune oral mucosal disease, OLP has different infiltration types of immune cells. Furthermore, 6 small molecules were proposed as promising novel treatment drugs for OLP patients. Therefore, our research may provide new impetus for the development of effective OLP biological treatment options.

Reveals of quercetin's therapeutic effects on oral lichen planus based on network pharmacology approach and experimental validation.

Oral lichen planus (OLP) is a localized autoimmune disease of the oral mucosa, with an incidence of up to 2%. Although corticosteroids are the first-line treatment, they cause several adverse effects. Quercetin, a naturally occurring compound, has fewer side-effects and provides long-term benefits. Besides, it has powerful anti­inflammatory activities. Here, we combined network pharmacology with experimental verification to predict and verify the key targets of quercetin against OLP. First, 66 quercetin-OLP common targets were analyzed from various databases. The protein-protein interaction (PPI) network was constructed. Topology analysis and MCODE cluster analysis of common targets were conducted to identify 12 key targets including TP53, IL-6 and IFN-γ and their connections. Gene functions and key signaling pathways, including reactive oxygen species metabolism, IL-17 pathway and AGE-RAGE pathway, were enriched by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Then, in vitro experiments showed that quercetin interfered with Th1/Th2 balance by acting on IL-6 and IFN-γ to modulate the immune system in treating OLP. Quercetin considerably affected the apoptosis and migration of T lymphocytes in OLP patients. Our study reveals the potential therapeutic targets and signaling pathways of quercetin associated with OLP, and establishes the groundwork for future clinical applications.

Immunohistochemical expression of cyclooxygenase-2 in oral lichen planus and normal oral mucosa.

BACKGROUND: Oral lichen planus (OLP) is a chronic inflammatory disease for which the pathogenesis is complex and not fully understood; autoimmunity has been suggested as a causative factor. World health organization (WHO) has classified OLP as a potentially malignant lesion. Cyclooxygenase-2 (COX-2) is an inducible key enzyme that generates prostanoids which play a critical role in inflammation, immunopathology; also considered as a malignant potential marker. AIMS: The present study was conducted to analyze and compare epithelial COX-2 expression in OLP clinical subtypes and normal oral mucosa to evaluate its role in the pathophysiology of the disease process. METHODS: This retrospective immunohistochemistry (IHC) study was performed on tissue sections of 30 OLP and 10 normal oral mucosae for COX-2 expression. STATISTICAL ANALYSIS USED: Descriptive and comparative statistical methods were done using 'one-way Analysis of Variance (ANOVA), 't' and Chi-square tests. RESULTS: All the OLP showed epithelial COX-2 expression; strong expression was noted in 80% of the OLP while normal oral mucosa sections showed no expression. Cox-2 expression was significantly higher in erosive lichen planus compared to reticular lichen planus. CONCLUSIONS: Strong expression of COX-2 in OLP suggested its important role in pathogenesis. Although COX-2 has been connected to malignant development and autoimmunity, as the malignant development in OLP is quite rare, this study suggests that increased levels of COX-2 seen here may support an autoimmune cause of the disease process.

Patch test of dental materials in Oral Lichen Planus with considering the role of saliva.

Lichen planus is the most common skin disease that affects the oral mucosa. Oral Lichen Planus is a T-cell-mediated autoimmune disorder. In the current study, for the first time, an oral cavity condition in skin patch tests with adding saliva is simulated. In addition, the patch results are compared with healthy subjects. Forty-one OLP patients and 63 healthy subjects were enrolled in the study. All participants were provided with patch tests, including allergens, in combination with saliva in chambers. Allergens from the European baseline (standard) series selected according to the most prevalent positive results in the previous study were applied. Positive results of Mercury and Cobalt tests were significantly higher in the case group. In this study, the differentiation of patients with lichen planus and lichenoid was identified according to the Van der Meij & Van der Waal criteria. The patch test was conducted for healthy individuals as well. The most important of all was the use of patients' saliva in the patch test, done for the first time in this field. In the case of OLP, a patch test can help identify positive reactions to dental materials; thus, the replacement of dental restorations may be needed.

Oral lichen planus: a microbiologist point of view.

Oral lichen planus (OLP) is a chronic disease of uncertain etiology, although it is generally considered as an immune-mediated disease that affects the mucous membranes and even the skin and nails. Over the years, this disease was attributed to a variety of causes, including different types of microorganisms. This review analyzes the present state of the art of the disease, from a microbiological point of view, while considering whether or not the possibility of a microbial origin for the disease can be supported. From the evidence presented here, OLP should be considered an immunological disease, as it was initially proposed, as opposed to an illness of microbiological origin. The different microorganisms so far described as putative disease-causing agents do not fulfill Koch's postulates; they are, actually, not the cause, but a result of the disease that provides the right circumstances for microbial colonization. This means that, at this stage, and unless new data becomes available, no microorganism can be envisaged as the causative agent of lichen planus.

Interferon-γ activated T-cell IRGM-autophagy axis in oral lichen planus.

Oral lichen planus (OLP) is an inflammatory immune disease featured by dense T-cell infiltrate and basal keratinocytes degeneration. Immunity related GTPase M (IRGM) is vital for the induction of autophagy. Our previous studies have demonstrated aberrant autophagy in OLP, however, the involvement of IRGM-autophagy axis in OLP has not yet been revealed. The expression of IRGM and autophagy activity were evaluated in oral mucosal tissues and peripheral T cells of OLP patients and healthy controls, respectively. We found significant upregulation of IRGM and LC3B in lesions of patients with OLP as compared with healthy donors. IRGM, LC3B and NOD2 levels were also elevated in the peripheral T cells of OLP. Then, knockdown of IRGM after electrotransfection with siRNA resulted in attenuated autophagy, growth inhibition, and apoptosis of T cells. In addition, preincubation with IFN-γ promoted the expression of IRGM mRNA and induced autophagy in T cells. Furthermore, IFN-γ decreased the proliferation and apoptosis of T cells, whereas facilitated the viability of keratinocytes in a co-culture system of activated T cells and keratinocytes. Taken together, activated IRGM-autophagy axis under IFN-γ regulation in T cells might participate in the immunoregulatory mechanism of OLP.

Can We Separate Oral Lichen Planus from Allergic Contact Dermatitis and Should We Patch Test? A Systematic Review of Chronic Oral Lichenoid Lesions.

This systematic review summarizes characteristics and treatment outcomes of dental amalgam-associated oral lichenoid lesions (OLLs) and oral lichen planus (OLP). Embase and MEDLINE were searched for original studies on OLLs or OLP associated with dental amalgam. Data extraction was completed from 44 studies representing 1855 patients. Removal of amalgam restorations led to complete resolution in 54.2% (n = 423/781), partial resolution in 34.8% (n = 272/781), and no resolution in 11.0% (n = 86/781) of the patients with OLLs, whereas complete resolution occurred in 37.1% (n = 72/194), partial resolution in 26.3% (n = 51/194), and no resolution in 36.6% (n = 71/194) of the patients with OLP. For patients with OLLs, 91.6% of the patients with positive patch tests and 82.9% with negative patch tests had improvement with removal of amalgam, whereas for patients with OLP, 89.2% of the patients with positive patch tests and 78.9% with negative patch tests had improvement with removal of amalgam. Our results suggest improvement occurs, regardless of patch testing status.

Omega-3 polyunsaturated fatty acids: a promising approach for the management of oral lichen planus.

BACKGROUND: Oral lichen planus (OLP) is a T-cell-mediated inflammatory disease with a risk of malignant transformation. Although the etiology of OLP is still uncertain, growing evidence suggests that oral microbiota, antigen-specific, and non-specific mechanisms are involved in the pathogenesis of OLP. Antigen-specific mechanisms include antigen presentation, T-cell activation, nuclear factor-kappa B signaling pathway, and cytokine secretion, while non-specific mechanisms consist of matrix metalloproteinases (MMP)-9 upregulation, psychological pressure, oxidative damage, aberrant expression of microRNAs (miRNAs), and autophagy. Till now, there is no cure for OLP, and the main purpose of OLP therapy is symptomatic control. FINDING: Seafood and its derivative omega-3 polyunsaturated fatty acids (n-3 PUFAs) can suppress antigen presentation, T-cell activation, and nuclear factor-kappa B signaling pathway, modulate the overexpressed inflammatory cytokines, inhibit the expression of MMP-9, as well as regulate the expression of miRNAs and autophagy. And they are possible agents for ameliorating psychological disorder and oxidative damage. Moreover, n-3 PUFAs supplementation has a beneficial effect on preventing tumorigenesis. CONCLUSION: n-3 PUFAs consumption may provide a non-toxic, inexpensive administration for OLP.

Oral Lichen Planus - Related Connection with HLA-System Antigens.

AIM: To determine whether there is an immunogenic connection and antigen difference between the HLA antigens in the erosive (EOLP) and reticular (ROLP) oral lichen planus. MATERIALS AND METHOD: 73 patients with ROLP and EOLP have been tested. Typing of the HLA antigens has been made for locus A and B. The typing of the HLA was conducted with the use of microlymphocyto toxic test by Terasaki. The reading of the findings has been conducted with an inverse microscope. When a reaction has 4 points it is considered to be positive. RESULTS: The most frequently typified antigens in ROLP from locus A are HLA А2 (57.57%) and А3 (33.33)%, and for locus B 21.21%. In EOLP it is А9 (8888%). In locus B a connection has been found with HLA B8 (77.77%). The statistical analysis with the ×2 test has shown that the carriers of HLA A9 display a relative risk (RR) of 3.65 and ×2=20.72. Consequently, there is high static importance for locus A p<0,001. For locus B, In EOLP for HLA B8, RR=6. 7 ×2=37.64 and p<0,001. ROLP has shown association with HLA A3, where RR=2. 31 and ×2 =9.14 and p<0.05. CONCLUSIONS: In ROLP A3 antigen and in EOLP A9 and A8 may be considered as carriers with proneness to OLP.

Alteration of Streptococcus salivarius in Buccal Mucosa of Oral Lichen Planus and Controlled Clinical Trial in OLP Treatment.

Oral lichen planus (OLP) is a T cell-mediated common chronic inflammatory mucosal disease, with limited therapies available for long-term use. Previous study showed that ratio of genus Streptococcus decreased significantly in OLP patients when compared with controls. Buccal cotton swab samples of 43 OLP patients and 48 healthy individuals were collected for real-time quantitative polymerase chain reaction (RT-PCR) to investigate relative abundance alteration of Streptococcus salivarius in OLP lesions. Bacterial supernatants of S. salivarius ATCC® BAA-2593™ were collected by centrifugation and added to HSC-3 cells, and quantitative analysis of expression of IL-1ß, IL-6, IL-8, and TNF-α in the HSC-3 cells was determined by RT-PCR. Then, a randomized, non-blinded, controlled study was conducted. Forty patients with symptomatic OLP were randomly allocated into two groups and received topical treatment of 0.1% triamcinolone acetonide dental paste (group A) and S. salivarius K12 lozenge (group B), respectively, for 4 weeks. Sign scores, visual analogue scale (VAS), and adverse reactions were recorded. Relative abundance of S. salivarius in the OLP group was lower than that of control group (P < 0.05). After treated with 0.1% supernatants of S. salivarius ATCC® BAA-2593™, the expression level of IL-6 in the HSC-3 cells significantly reduced (P < 0.001), while IL-1ß, IL-8, and TNF- α showed a decreasing tendency (P > 0.05). There was significant reduction in sign scores and VAS scores in both groups after the 4-week treatment, with no significant difference between two groups. No adverse reaction was observed. S. salivarius might maintain local immune balance by inhibiting the NF-κB pathway. Topical application of Streptococcus salivarius K12 seemed to be effective in treatment of symptomatic OLP, especially with promising potential in long-term use. More detailed clinical studies with long follow-up period and standardized usage/dosage are expected to acquire definite conclusions.

Induction of High Endothelial Venule-like Vessels in Oral and Cutaneous Lichen Planus: A Comparative Study.

Lichen planus (LP) is a chronic inflammatory mucocutaneous disease involving the oral mucosa and skin. Both oral LP (OLP) and cutaneous LP (CLP) are histopathologically characterized by dense subepithelial lymphocyte infiltrates; however, the mechanisms underlying lymphocyte recruitment to sites of LP lesions are not fully understood. Here, we assessed the induction of peripheral lymph node addressin (PNAd)-expressing high endothelial venule (HEV)-like vessels in 19 OLP and 17 CLP cases. To do so, we performed immunohistochemical staining for PNAd and CD34, followed by quantitative analysis. We also conducted triple immunohistochemistry for PNAd and either CD3 and CD20 or CD4 and CD8 to identify the lymphocyte subset preferentially recruited via HEV-like vessels. PNAd-expressing HEV-like vessels were induced in and around lymphocyte aggregates in all cases of OLP and in 10 of 17 CLP cases, and these vessels were more frequently observed in OLP relative to CLP. Although the number of T-cells attached per HEV-like vessel exceeded the number of B-cells in both OLP and CLP, the number of CD4+ T-cells attached was greater than the number of CD8+ T-cells only in OLP. These findings combined suggest that PNAd-expressing HEV-like vessels play a more important role in the pathogenesis of OLP compared with CLP.

Identificación de apoptosis liquen plano oral con caspasa 3 / Apoptosis identification in oral lichen planus with caspase 3

Las enfermedades autoinmunes tienen múltiples manifestaciones en estomatología, entre las más frecuentes se encuentra el liquen plano oral (LPO), se trata de una enfermedad crónica con manifestaciones clínicas en piel y mucosas. Se agrupa en dos formas anatomoclínicas, la de curso evolutivo benigno identificado como típico y la susceptible de transformación maligna, identificada como atípico. Histológicamente, la degeneración vacuolar del estrato basal del epitelio es el signo histomorfológico patognomónico seguido de apoptosis celular. La apoptosis es un evento esencial entre los fenómenos del ciclo celular, sucede con la finalidad de eliminar células dañadas o inútiles. De todas las proteínas implicadas las caspasas son los responsables de la ejecución de este mecanismo, especialmente la caspasa 3 por fragmentar y activar otras caspasas responsables de la proteólisis. El potencial de transformación maligna del LPO podría estar en relación con el fallo de este mecanismo de regulación del ciclo de las células epiteliales agredidas y la persistencia de células dañadas. El presente trabajo de investigación tuvo como objetivo analizar la presencia y proporción de apoptosis en las distintas variantes de LPO con técnicas histológicas de rutina y posterior aplicación de inmunohistoquímica, utilizando como marcador la caspasa 3. Se obtuvieron 20 biopsias de LPO de cinco variedades clínicas nueve variantes típicas (VT): cinco placa, cuatro reticulares y 11 variantes atípicas (VA): dos atróficos, seis erosivos, tres ampollares. El método de evaluación fue semicuantitativo, se consideró en función del porcentaje, se realizó un recuento celular de un total de 100 células en cinco campos de gran aumento considerando las siguientes categorías según ausencia, presencia leve (< 10%), moderada (10 ≤ 25%), intensa (25 ≤ 50%), no valorables. Se encontró una buena correlación de los cambios histológicos y el grado de expresión del marcador utilizado para poner en evidencia la apoptosis, sobre todo con las muestras de LPO de variante atípica. En los casos de las variantes atípicas de liquen observados en comparación con la tinción de rutina (H/E) se observó igualdad o una disminución en algunos casos del número de queratinocitos apoptóticos. En cuanto a las variantes clínicas consideradas «típicas¼ se observó que el recuento de células en apoptosis estaba significativamente elevado. Obtuvimos excelentes resultados con el inmunomarcador caspasa 3, el cual coincide con la literatura en su alta sensibilidad como recurso para cuantificar el número de apoptosis en estas lesiones orales (AU)

Autoimmune diseases have multiple manifestations in stomatology, among the most frequent is oral lichen planus (LPO), it is a chronic disease with clinical manifestations in skin and mucous membranes. It is grouped into two anatomoclinic forms, the benign evolutionary course identified as typical and susceptible to malignant transformation, identified as atypical. Histologically, vacuolar degeneration of the basal stratum of the epithelium is the pathognomonic histomorphological sign followed by cellular apoptosis. Apoptosis is an essential event among cell cycle phenomena, it happens in order to eliminate damaged or useless cells. Of all the proteins involved, caspases are responsible for the execution of this mechanism, especially caspase-3 for fragmenting and activating other caspases responsible for proteolysis. The potential for malignant transformation of the LPO could be related to the failure of this mechanism to regulate the cycle of attacked epithelial cells and the persistence of damaged cells. This research work aimed to analyze the presence and proportion of apoptosis in the different variants of LPO with routine histological techniques and subsequent application of immunohistochemistry, using caspase as a marker 3. 20 LPO biopsies from 5 clinical varieties were obtained 9 typical variants (VT): 5 plate, 4 reticular and 11 atypical variants (VA): 2 atrophic, 6 erosive, 3 ampoules. The evaluation method was semi-quantitative considering the percentage, making a cell count of a total of 100 cells, in five large-scale fields considering the following categories according to absence, mild presence (< 10%), moderate (10 ≤ 25%), intense (25 ≤ 50%), not valuable. We found a good correlation of histological changes and the degree of expression of the marker used to highlight apoptosis, especially with the atypical variant LPO samples. In the cases of atypical variants of lichen observed, compared with routine staining (H/E) we find equality or a decrease in some cases of the number of apoptotic keratinocytes. For clinical variants considered «typical¼ it was observed that the cell count in apoptosis was significantly increased. We obtained excellent results with the caspase 3 immunomarker coinciding with the literature of its high sensitivity as a resource to quantify the number of apoptosis in these oral lesions (AU)

Possible Mechanisms Involved in the Cooccurrence of Oral Lichen Planus and Hashimoto's Thyroiditis.

Oral lichen planus (OLP) is a chronic inflammatory oral mucosal disorder mediated by T cells, with a multifactorial etiology. Hashimoto's thyroiditis (HT) is a common autoimmune disease characterized by hypothyroidism. Although many clinical studies conducted over the past several decades have reported the cooccurrence of OLP and HT, the underlying mechanism remains unclear. This review summarizes potential mechanisms that might be involved in the cooccurrence of OLP and HT. We find that OLP and HT share a common or overlapping pathogenesis in terms of immune, heredity, environmental, and hormonal factors, which might cause cooccurrence. Furthermore, considering the latency of HT, a routine screen for thyroid diseases, particularly HT, is suggested for confirmed OLP patients.

[Effects of interleukin-35 on the balance of helper T cell 17/regulatory T cell in peripheral blood of patients with oral lichen planus].

Objective: To investigate the effects of exogenous interleukin (IL)-35 on the balance of helper T cell 17 (Th17) and regulatory T cell (Treg) in peripheral blood of patients with oral lichen planus (OLP). Methods: Totally 12 peripheral blood samples of OLP patients (OLP group, one male and 11 female, 26-68 years old; four cases of reticular OLP and eight cases of erosive OLP) were collected from patients of Department of Oral Mucosal Specialist of the Affiliated Hospital of Guizhou Medical University from October to December 2016. During the same period, thirteen normal peripheral blood samples were collected from the Physical Examination Center of the Affiliated Hospital of Guizhou Medical University (normal control group, one male and 12 female, 20-68 years old). The peripheral blood mononuclear cells (PBMC) were extracted in sterile condition and CD4+ T cells were sorted by flow cytometry (FCM). Quantitative real-time PCR (qPCR) technique was used to detect the mRNA expression levels of retinoid-related orphan nuclear γt (RORγt) and forkhead box3 (Foxp3). The CD4+ T cells were divided into experimental group and control group. The CD4+ T cells of experimental group were cultured in vitro by adding rhIL-35, and the CD4+ T cells of control group were cultured with the same volume of phosphate buffered saline (PBS). After the completion of the culture, the cells were collected. The expression levels of the same factors were detected by qPCR. Results: The expression [M(Q(25), Q(75))] of Foxp3 [0.15 (0.09, 0.30)] and RORγt mRNA [1.04 (0.45, 2.15)] in the CD4+ T cells of OLP were significantly higher than those in normal control group [0.04 (0.02, 0.06), 0.10 (0.05, 0.11)] (Z=-4.134, P<0.01; Z=-3.699, P<0.01). The ratio of ROR γt/Foxp3 mRNA in OLP group [6.22(3.67, 15.34)] was higher than that in normal control group [2.50 (1.24, 5.23)] (Z=-2.665, P=0.007). In the CD4+ T cells of OLP patients, the expression of Foxp3 mRNA in the experiment group [0.40 (0.21, 1.22)] was higher than that in the control group [0.15 (0.11, 0.26)](Z=-2.510, P=0.012), and the expression of ROR γt mRNA between two groups showed no significant difference (P>0.05). The ROR γt/Foxp3 mRNA ratio [3.44 (1.55, 8.16)] of the experiment group was lower than that in the control group [6.22 (4.43, 12.21)] (Z=-2.746, P=0.006). Conclusions: There was a Th17/Treg imbalance with predominated by Th17 cells in the peripheral blood of patients with OLP. Exogenous rhIL-35 had an immunomodulatory effect on the balance of Th17/Treg.

MicroRNA-26a/b have protective roles in oral lichen planus.

Oral lichen planus (OLP) is a kind of oral epithelial disorder featured with keratinocyte apoptosis and inflammatory reaction. The pathogenesis of OLP remains an enigma. Herein, we showed that the levels of miR-26a/b were robustly down-regulated in oral mucosal biopsies, serum and saliva in OLP patients compared with healthy control. Moreover, we found the binding sites of vitamin D receptor (VDR) in the promoter regions of miR-26a/b genes and proved that the induction of miR-26a/b was VDR dependent. The reduction of miR-26a/b expression was also detected in the oral epithelium of vitamin D deficient or VDR knockout mice. miR-26a/b inhibitors enhanced apoptosis and Type 1T helper (Th1) cells-related cytokines production in oral keratinocytes, whereas miR-26a/b mimics were protective. Mechanistically, we analyzed miRNA target genes and confirmed that miR-26a/b blocked apoptosis by directly targeting Protein Kinase C δ (PKCδ) which promotes cellular apoptotic processes. Meanwhile, miR-26a/b suppressed Th1-related cytokines secretion through targeting cluster of the differentiation 38 (CD38). In accordant with miR-26a/b decreases, PKCδ and CD38 levels were highly elevated in OLP patients' samples. Taken together, our present investigations suggest that vitamin D/VDR-induced miR-26a/b take protective functions in OLP via both inhibiting apoptosis and impeding inflammatory response in oral keratinocytes.

Potential roles of the CCL17-CCR4 axis in immunopathogenesis of oral lichen planus.

BACKGROUND: Oral lichen planus (OLP) is a T cell-mediated chronic inflammatory disease. C-C chemokine receptor type 4 (CCR4) and its cognate C-C motif chemokine ligand 17 (CCL17) play a key role in T-cell activation and trafficking, but their implication in OLP pathogenesis has not been explored. Our study was designed to analyze the expression and function of the CCL17-CCR4 axis in OLP. METHODS: The mRNA expression levels of CCL17 and CCR4 in the circulating T cells of OLP subjects were examined by quantitative real-time PCR. The protein levels of CCL17 and CCR4 in the peripheral blood of OLP subjects were detected by enzyme-linked immunosorbent assay (ELISA) and Simple Western assay, respectively. The functional relevance of increased expression of CCL17 and CCR4 in OLP was demonstrated in proliferation, apoptosis, and migration assays. RESULTS: The mRNA and protein expression levels of CCL17 and CCR4 in the peripheral blood of patients with OLP were significantly upregulated compared with those of controls. CCL17 induced the migration of OLP T cells. In addition, blocking CCR4 with a small molecule CCR4 antagonist not only inhibited the proliferation and migration of OLP T cells but also promoted the apoptosis of OLP T cells. CONCLUSION: Our findings indicate that the CCL17-CCR4 axis might be responsible for the inflammatory infiltration of T cells in OLP.

Enhanced T-cell proliferation and IL-6 secretion mediated by overexpression of TRIM21 in oral lesions of patients with oral lichen planus.

BACKGROUNDS: To explore the expression and functions of the tripartite motif-containing protein 21 (TRIM21) in oral lichen planus(OLP) lesions. METHODS: Paraffin sections of buccal mucosa samples from 15 cases of reticular oral lichen planus (OLP) patients and 10 healthy controls were used for immunohistochemistry to determine expression and distribution of TRIM21. Buccal mucosae from 11 OLP patients and seven healthy controls were analyzed by qPCR to quantify its gene expression. Peripheral blood mononuclear cells and CD3+ cells from four pairs of age- and sex-matched OLP patients and healthy controls were isolated for immunocytochemistry and culture. Following lentivirus-mediated overexpression of TRIM21 gene in CD3+ cells, CCK-8 was applied to evaluate cell proliferation. Cytokines including IL-2, IL-4, IL-5, IL-6, IL-10, TNF-α, and IFN-γ in the supernatants were measured by the cytometric bead array and verified by ELISA. RESULTS: A larger number of TRIM21-positive cells infiltrating the lamina propria were observed in OLP lesions by immunohistochemistry than those of healthy controls. Significantly higher transcription of TRIM21 was revealed by qPCR. TRIM21 overexpression in CD3+ cells significantly enhanced the proliferation and IL-6 secretion in CD3+ cells from 12 to 72 hours. CONCLUSION: Overexpressed TRIM21 in OLP may be a primary proinflammatory molecule rather than a secondary and inducible regulatory factor in immunopathogenesis of OLP.