Is there a role for tumor necrosis factor-alpha (TNF-alpha) in oral lichen planus?

Tumour Necrosis Factor Alpha (TNF-α) and Oral Squamous Cell Carcinoma

Uncovering the inflammatory mechanisms underpinning initiation, progression, and promotion of oral squamous cell carcinoma (OSCC) development is fundamental to the rational pursuit of targeted therapeutics. Here we present a review of the current knowledge of the role of TNF-α in the aetiology, pathogenesis, and potential therapies with regards to OSCC. TNF-α is worthy of particular attention in OSCC, with its presence demonstrated to enhance cell proliferation and its downregulation demonstrated to inhibit proliferation and migration in other carcinomas in both in vitro and in vivo models and oral cancer patients. Increased TNF-α in the OSCC tumour microenvironment has been demonstrated to favour invasion through promotion of firstly the pro-inflammatory, pro-invasive phenotypes of OSCC cells and secondly its paracrine mechanism mediating recruitment and activation of inflammatory cells. Polymorphisms affecting the gene expression of TNF-α have been strongly associated with an increased risk for oral squamous cell carcinoma. A number of studies have considered TNF-α within biofluids, including saliva and serum, as a potential biomarker for the early detection of OSCC, as well as its staging, differentiation, and prognosis. The broad and multifaceted role that TNF-α plays in many inflammatory states presents an obvious confounder, particularly with demonstrated increased TNF-α levels in common oral disease states. Lastly, biologic agents targeting TNF-α are currently in clinical use for immune-mediated inflammatory rheumatological and gastrointestinal diseases. There is the potential that these biological agents might have an adjunctive role in OSCC prevention and treatment.

Updates on immunological mechanistic insights and targeting of the oral lichen planus microenvironment

Oral lichen planus (OLP) is a chronic immune inflammatory disease that is an oral potentially malignant disorder (OPMD), occurs in the oral mucosa and affects approximately 0.5% to 4% of the general population. There are usually five types of OLP: reticular/papular, plaque-like, atrophic/erythematous, erosive/ulcerative, and bullous. Furthermore, the chance of causing oral squamous cell carcinoma (OSCC) is 1.4%. Although the etiology of OLP is still unknown, accumulating evidence supports that immune dysregulation may play a vital role in the pathogenesis of OLP, especially the massive production of various inflammatory cells and inflammatory mediators. In this review, we focus on the relationship between OLP and its immune microenvironment. We summarize current developments in the immunology of OLP, summarizing functional cell types and crucial cytokines in the OLP immune microenvironment and the underlying mechanisms of key signaling pathways in the OLP immune microenvironment. We highlight the application potential of targeted immune microenvironment therapy for OLP.

Profiling and Characterization of Localized Cytokine Response in Congenital Cleft Affected Lip Tissue

(1) Background: Despite cleft lips and palates belonging to the most common orofacial congenital anomalies, their morphopathogenesis is not yet fully understood. The study aimed to determine the distribution and relation of cytokines interferon-γ (IFN-γ), tumor necrosis factor-alpha (TNF-α), interleukin (IL)-2, IL-7, IL-12, and IL-13 in the cleft affected mucosa of the lip. (2) Materials and Methods: Twenty cleft lip (CL) mucosal samples and seven control tissues of oral cavity mucosa were included in the study. Specimen were obtained during reconstruction surgeries and processed by hematoxylin and eosin staining and immunohistochemistry for IFN-γ, TNF-α, IL-2, IL-7, IL-12, and IL-13. (3) Results: The distribution of cytokines was higher overall in the cleft affected epithelium compared to the connective tissue, with TNF-a, IL-2, and IL-12 displaying the highest number of immunopositive cells. With the exception of IL-2, CL specimen showed higher immunoreactivity. IFN-γ displayed only minor immunoreactivity, with no expression in the control epithelium. Correlation analysis was strongest between CL epithelial IL-13 and IFN-γ (z = 0.71, p < 0.0001). (4) Conclusions: The CLP affected epithelium displays high degrees of plasticity in expressing different cytokines, pointing towards the stimulation of a local adaptive immune response based on consistent inflammatory processes.

Salivary Biomarkers and Their Application in the Diagnosis and Monitoring of the Most Common Oral Pathologies

Saliva is a highly versatile biological fluid that is easy to gather in a non-invasive manner—and the results of its analysis complement clinical and histopathological findings in the diagnosis of multiple diseases. The objective of this review was to offer an update on the contribution of salivary biomarkers to the diagnosis and prognosis of diseases of the oral cavity, including oral lichen planus, periodontitis, Sjögren’s syndrome, oral leukoplakia, peri-implantitis, and medication-related osteonecrosis of the jaw. Salivary biomarkers such as interleukins, growth factors, enzymes, and other biomolecules have proven useful in the diagnosis and follow-up of these diseases, facilitating the early evaluation of malignization risk and the monitoring of disease progression and response to treatment. However, further studies are required to identify new biomarkers and verify their reported role in the diagnosis and/or prognosis of oral diseases.

Mast cell expression in oral lichen planus: A systematic review

Lichen planus is a common chronic, inflammatory, immune-mediated mucocutaneous disorder affecting the skin and mucosa. The role of mast cells in the genesis of lichen planus has been debated. Establishing a definitive part played by mast cells and its degranulation would possibly provide a permanent, cost-effective treatment modality for oral lichen planus (OLP). This review aims to study the expression of mast cells qualitatively and quantitatively in OLP. The research questions were framed to assess the mast cell count, localization within the epithelium basement membrane zone and degranulation of mast cells. We performed a systematic search of PubMed, Medline, Cochrane and Web of Science. We found a total of 120 studies from which 12 were found suitable for the review. There is a marked increase in the number of mast cells in OLP. The mast cells were seen in increased numbers in the epithelial and connective tissue junction at areas of basement membrane disruption. There was also an increase in the degranulation of mast cells. It is evident that there is an increase in the mast cell number in lichen planus and its subsequent degranulation.

A Case of Cycloserine-Induced Lichenoid Drug Eruption Supported by the Lymphocyte Transformation Test

Lichenoid drug eruption (LDE) is a rare form of delayed-type drug eruption. Among anti-tuberculosis (Tb) agents, cycloserine (CS) has been reported as a rare cause of LDE. Positive results on the lymphocyte transformation test (LTT) have not been reported in patients with LDE. In the present case, we performed LTT and a patch test, and successfully proved CS as the offending drug in this patient, who had been treated with multiple anti-Tb drugs. These observations suggest that CS should be considered a possible cause of LDE and that LTT can be an option for the diagnosis of LDE.

A Review of the Use of Infliximab to Manage Cutaneous Dermatoses

Background:

Infliximab is a chimeric monoclonal antibody that binds specifically to human tumor necrosis factor-alpha (TNF-α), decreasing the effect of the cytokine in inflammatory diseases.

Objective:

The aim of this study was to review the efficacy and safety of infliximab in the treatment of dermatological diseases.

Methods:

A MEDLINE search (1966–January 2003), using the keyword “infliximab” was performed to find relevant articles pertaining to the use of infliximab in dermatology.

Results:

Infliximab has been used in the following dermatological diseases: psoriasis, Behçet's disease, graft versus host disease, hidradenitis suppurativa, panniculitis, pyoderma gangrenosum, SAPHO (synovitis, acne, pustulosis, hyperostosis and osteitis) syndrome, sarcoidosis, subcorneal pustular dermatosis, Sweet's syndrome, toxic epidermal necrolysis, and Wegener's granulomatosis. There is a generally good safety profile for infliximab, which is similar to that when it is used to treat Crohn's disease and rheumatoid arthritis.

Conclusion:

Although not approved for use in dermatological diseases, there have been numerous reports of the efficacy of infliximab in cutaneous inflammatory diseases. The most promise lies in those diseases that have increased amounts of TNF-α in the cutaneous lesions, such as psoriasis.

[Immunomorphology of oral lichen planus]

The article is devoted to immunohistochemical study of reticular and erosive forms of oral lichen planus. Morphological examination of the reticular form revealed the increased number of Langerhans cells (CD1a), mast cells (CD25) and T lymphocytes (CD4, CD8, CD16) in the oral epithelium. Activation of these cells leads to the secretion of TNF-α and destruction of basal keratinocytes, which manifests as a focal reduction of intercellular protein expression of E-cadherin. Destruction of basal keratinocytes in a reticular form of oral lichen planus is accompanied by a significant decrease in proliferative activity of the basal cell layer (21.7±10.2%) compared with normal mucosa (33.6±7.0%), p=0.0045. In erosive form along with the above changes IgG and C3d complement's elements are revealed, which confirms the activation of immune complex mechanisms in the erosion area.

MicroRNAs in oral lichen planus and potential miRNA-mRNA pathogenesis with essential cytokines: a review

Oral lichen planus (OLP) is a potentially premalignant condition with unknown pathogenesis. Immune and inflammatory factors are thought to play important roles in the development of OLP, and cytokines, such as interferon (IFN)-γ and tumor necrosis factor (TNF)-α, can act as critical players in the immunopathogenesis of OLP. MicroRNAs (miRNAs) are closely correlated with cytokines in various inflammation-related diseases. In patients with OLP, miRNA-146a and miRNA-155 are increased in peripheral blood mononuclear cells, and numerous miRNAs have been shown to exhibit altered expression profiles in lesions. Although the microRNA-messenger RNA (miRNA-mRNA) network is thought to be involved in the development of OLP, in-depth studies are lacking. Here, we summarize current data on the mechanisms of action of miRNAs regulating typical cytokines in OLP, including interleukin (IL)-10, IL-17, IL-22, IFN-γ, and TNF-α, to study the genetic basis of the pathogenesis of OLP and to provide prospects of therapy.

Oral lichen planus

Lichen planus is an inflammatory mucocutaneous disease that can affect the skin, hair, nails, and mucosal surfaces. Mucosal sites of involvement include oral, genital, ocular, otic, esophageal, and, less commonly, bladder, nasal, laryngeal, and anal surfaces. Oral lichen planus is a mucosal variant of lichen planus, which tends to affect women more often than men, with a typically more chronic course and potential for significant morbidity. Treatment can be challenging, and there is potentially a low risk of malignant transformation; however, therapeutic benefits can be obtained with various topical and systemic medications. Clinical monitoring is recommended to ensure symptomatic control. Increasing awareness and recognition of this entity have continued to fuel advances in therapy and in our understanding of the disease.

Dysplastic change rate in cases of oral lichen planus: A retrospective study of 112 cases in an Iranian population

Backgrounds:

Lichen planus is a chronic systemic disease and oral mucosa is commonly involved. Oral lichen planus (OLP) most commonly affects middle-aged women. The prevalence of the disease ranges between 0.5% and 2.6% in the general population and the range of malignant transformation varies between 0% and 10%.

Objectives:

To assess the rate of malignant transformation of OLP samples.

Materials and Methods:

This retrospective study was carried out on 112 medical records of patients with histological diagnosis of OLP who attended the Department of Pathology at the Educational Hospital from 2005 to 2012. H&E-stained slides were reviewed by two pathologists using strict clinical and histopathological diagnostic World Health Organization (WHO) criteria. Dysplastic changes were diagnosed and graded according to the latest WHO classification.

Results:

Of the 112 cases diagnosed as OLP, there were 39 males and 73 females and the patients’ ages ranged from 15 to 86 years (mean age 44.5 years). The erosive form with fifty cases was the most common clinical type and the papular type with one case was the least common clinical type. Regarding the site, the buccal mucosa was the most common site with 52 cases. Totally, dysplastic changes were found in 12 samples, among them five cases showed mild dysplasia and seven cases showed moderate dysplasia. One case developed oral squamous cell carcinoma after 3 years.

Conclusion:

OLP is considered as a premalignant condition by the WHO and several authors. Although the malignancy rate is not so high, to reduce morbidity and mortality from cancer arising on OLP lesions, a regular follow-up examination is recommended.

Quantitative Analysis of Salivary TNF-α in Oral Lichen Planus Patients

Objective. The aim of this study was to quantitatively evaluate the salivary tumor necrosis factor-alpha (TNF-α) level in oral lichen planus patients and to compare the levels of TNF-α between saliva and serum of OLP and controls. Methods. Serum and whole saliva from 30 patients with active lesions of oral lichen planus (OLP) and 30 healthy persons were investigated for the presence of TNF-α by enzyme immunoassay. Student's independent t-test and two-sample binomial proportion test were used to calculate significance of the mean values of TNF-alpha in serum and saliva and to determine the proportions of the detected and nondetected samples in both groups. Results. Proportion of detection and the mean of detectability between saliva and serum of Group B show an almost equal value, which suggests that saliva can be a good alternate to serum to analyze TNF-α in oral lichen planus patients.

Immunohistochemical expression of perforin in lichen planus lesions

BACKGROUND

Lichen planus (LP) is a chronic inflammatory papulosquamous skin disease characterized by epidermal basal cell damage and a particular band-like infiltrate predominantly of T cells in the upper dermis. It is characterized by the formation of colloid bodies representing apoptotic keratinocytes. The apoptotic process mediated by CD8+ cytotoxic T lymphocytes and natural killer cells mainly involves two distinct pathways: the perforin/granzyme pathway and the Fas/FasL pathway. So far, little is known regarding the role of perforin-mediated apoptosis in LP.

AIM

Is to study the expression and distribution of perforin in the epidermis and dermis of lesional LP skin.

MATERIALS AND METHODS

Skin biopsy specimens from lesional skin of 31 patients with LP and 10 healthy persons were analyzed by immunohistochemistry.

RESULTS

Significant accumulation of perforin + cells was found in both epidermis and dermis of LP lesions compared with healthy skin. Perforin expression was significantly upregulated in the epidermis of LP lesions.

CONCLUSION

Accumulation of perforin + cells in the epidermis of LP lesions suggest a potential role of perforin in the apoptosis of basal keratinocytes.

Inflammation-related cytokines in oral lichen planus: an overview

Cytokines are powerful mediators which play a central role in both innate and adapted immune responses. Aberrant productions of cytokines may lead to the onset of immune deficiency, allergy or autoimmunity, which are involved in the mechanisms of various immune-mediated inflammatory diseases. Oral lichen planus (OLP) is a chronic inflammation disease affecting the oral mucosa with unknown aetiology. Previous studies have described the abnormal expression patterns of various inflammation-related cytokines, such as IL-1, 2, 4, 5, 6, 8, 10, 12, 17, 18, TGF-β, IFN-γ and TNF-α, in lesions, saliva, serum and peripheral blood mononuclear cells from patients with OLP, which may reflect the immune dysregulation status and emerge as central players in the immunopathogenesis of OLP. Besides, the gene polymorphisms of several cytokines such as IFN-γ, TNF-α, IL-4, IL-10 have been found to be involved in the susceptibility of OLP. In this review, we gave a brief introduction of the characteristics and biological functions of these inflammation-related cytokines and summarized for the first time the current knowledge on the involvement of inflammation-related cytokines in OLP. Further research on the exact roles of these cytokines will aid the understanding of the pathogenesis and the identification of novel therapeutic approaches of OLP.

Association of cytokine gene polymorphisms with oral lichen planus in Malayalam-speaking ethnicity from South India (Kerala)

Oral lichen planus (OLP) is a chronic mucocutaneous condition that affects the oral mucous membrane as well as skin. It is a chronic cell-mediated autoimmune condition where the T-cell-mediated immune response plays an important part in the pathogenesis by causing damage to basal keratinocytes in oral mucosa. Cytokine gene polymorphisms have an unquestionable role in the orchestration of the immune response, leading to different functional scenarios, which in turn influence the outcome of the disease establishment and evolution. The purpose of this study was to understand the role of these cytokine gene polymorphisms in the tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and IL-6 genes with OLP in 101 individuals of Malayalam-speaking ethnicity from South India (Kerala). We further investigated the role of these polymorphisms in patients suffering from OLP with other comorbid factors. Genotyping was carried out by polymerase chain reaction-restriction fragment length polymorphism. The results demonstrate that the A allele in the TNF-α -308 polymorphism could play an important role in the susceptibility to OLP. IL-1β +3954 in OLP was associated with other comorbid factors in both allelic and genotypic combinations. However, when patients suffering from OLP were stratified to understand the involvement of other comorbid factors, we observed that the T and C alleles were independent risk factors for chronic periodontitits and diabetes mellitus. On the other hand, IL-6 -597 did not show any disease association with OLP in the study population. This study indicates that proinflammatory cytokines are an important factor in understanding the disease burden of OLP and their comorbid factors.

Mast cells distribution and variations in epithelium thickness and basement membrane in oral lichen planus lesion and oral lichenoid reaction

Background:

Oral lichen planus (OLP) is a chronic mucocutaneous lesion with unknown etiology. Oral lichenoid lesions (OLL) comprise a family of lesions with different etiologies. Both lesions have similar clinical and histopathologic characteristics although their management is different. Differential diagnosis between OLP and OLL has always been a major challenge.

Materials and Methods:

In this prospective analytical study, the role of mast cells in pathogenesis of these lesions was investigated by evaluation of 52 patients with clinical and histopathological diagnosis of OLP (26 cases) and OLL (26 cases) based on WHO criteria, and by applying a more accessible staining methods, Hematoxylin and Eosin, toluidine blue (histochemistry) and Periodic Acid Schiff staining. In order to distinguish these two lesions, number of mast cells and thickness of epithelium and basement membrane were measured using light microscopy. Data were analyzed by SPSS software using t-test method (P<0.001).

Results:

No significant difference was observed between the total numbers of mast cells of two groups (P=0.148), but a statistically significant difference was detected between degranulated mast cells in two groups (P<0.001). A significant difference was also observed between the thickness of epithelium in two groups (P<0.001), although no difference was seen between basement membrane thickness in these lesions.

Conclusion:

Number of degranulated mast cells in reticular layer of corium in lichenoid lesions was more than that of OLP. This implies that despite the increase in number of these cells, in both groups of diseases, the role of these cells has not been the same in pathogenesis of the diseases. Moreover, the epithelium thickness was lower in lesions of OLP compared to lesions of oral lichenoid, so this parameter may be a useful criterion together with other histopathological and clinical finding to discriminate these lesions. However, discrepancy of basement membrane thickness can not be a reliable criterion. Finally we suggest more accessible staining methods which are reliable for differentiation of these two lesions.

Degranulated mast cells and TNF-α in oral lichen planus and oral lichenoid reactions diseases

Background:

The objective of this study was to assess mast cells and TNF-α in oral lichen planus (OLP) and oral lichenoid reactions (OLR) patients as diagnostic marker to the differential diagnosis of OLP and OLR diseases.

Materials and Methods:

In this cross-sectional study, samples were obtained from 30 OLP and 30 OLR patients, between June 2010 and March 2011 in Dental clinic of the University of Isfahan, Iran. Mast cells in the reticular layer of the lamina propria for samples were evaluated using toluidine blue method and immunohistochemical technique. The clinical relevant data taken into account were: demographical data, total number and degranulated mast cells, ratio of degranulated mast cells and TNF-α positive degranulated mast cells.

Results:

In OLP and OLR, the total mast cells were 21.2 ± 7.9 and 20.3 ± 6.8, degranulated mast cells were 15.5 ± 6.9 and 19.2 ± 6.9, ratio of degranulated mast cells to total mast cells were 0.716 ± 0.067 and 0.946 ± 0.081, and TNF-α positive degranulated mast cells were 13.6 ± 6.3 and 17.1 ± 6.04, respectively. There was no significant difference for the total mast cells. But degranulated mast cells, ratio of degranulated mast cells and TNF-α positive degranulated mast cells in OLR were significantly higher than OLP patients.

Conclusions:

Our results showed that the degranulated mast cells, ratio of degranulated mast cells and TNF-α in OLR was significantly more than OLP patients and these may be able to be used as diagnostic markers to the differential diagnosis of OLP and OLR.

Oral lichen planus as a preneoplastic inflammatory model

Oral lichen planus (OLP) is a chronic oral inflammatory disease of unknown etiology. According to reports, 1-2% of OLP patients develop oral squamous cell carcinoma (OSCC) in the long run. While World Health Organization (WHO) classifies OLP as “a potentially malignant disorder,” it is still a matter of debate which mechanisms drive OLP to such a condition. The current hypothesis connecting OLP and OSCC is that chronic inflammation results in crucial DNA damage which over time results in cancer development. Initial studies investigating the OLP and OSCC link were mainly retrospective clinical studies. Over the past years, several amount of information has accumulated, mainly from molecular studies on the OLP malignant potential. This article is a critical review of whether OLP has a malignant potential and, therefore, represents a model of preneoplastic inflammation.

Oral health and pathology: a macrophage account

Macrophages are present in healthy oral mucosa and their numbers increase dramatically during disease. They can exhibit a diverse range of phenotypes characterised as a functional spectrum from pro-inflammatory to anti-inflammatory (regulatory) subsets. This review illustrates the role of these subsets in the oral inflammatory disease lichen planus, and the immunosuppressive disease oral squamous cell carcinoma (SCC). We conclude that the role of macrophages in driving progression in oral disease identifies them as potential therapeutic targets for a range of oral pathologies.

Oral lichen planus and lichenoid reactions: etiopathogenesis, diagnosis, management and malignant transformation

Lichen planus, a chronic autoimmune, mucocutaneous disease affects the oral mucosa (oral lichen planus or OLP) besides the skin, genital mucosa, scalp and nails. An immune mediated pathogenesis is recognized in lichen planus although the exact etiology is unknown. The disease most commonly affects middle-aged females. Oral lichenoid reactions (OLR) which are considered variants of OLP, may be regarded as a disease by itself or as an exacerbation of an existing OLP, by the presence of medication (lichenoid drug reactions) or dental materials (contact hypersensitivity). OLP usually presents as white striations (Wickham's striae), white papules, white plaque, erythema, erosions or blisters. Diagnosis of OLP is established either by clinical examination only or by clinical examination with histopathologic confirmation. Direct immunofluorescence examination is only used as an adjunct to the above method of diagnosis and to rule out specific autoimmune diseases such as pemphigus and pemphigoid. Histopathologic features of OLP and OLR are similar with suggestions of certain discriminatory features by some authors. Topical corticosteroids are the treatment of choice for OLP although several other medications have been studied including retinoids, tacrolimus, cyclosporine and photodynamic therapy. Certain OLP undergo malignant transformation and the exact incidence and mechanisms are still controversial. In this paper, etiopathogenesis, diagnosis, management and malignant transformation of OLP and OLR have been reviewed.

Involvement of granzyme B and granulysin in the cytotoxic response in lichen planus

BACKGROUND

Lichen planus is an inflammatory dermatosis involving either skin and/or mucosal epithelial surfaces. A cell-mediated cytotoxicity response is the main suspected mechanism of this dermatosis. Granzyme B and granulysin are components of the cytoplasmic granules of cytotoxic T lymphocytes and natural killers. They are involved in cell-mediated apoptosis. This work studies the possible implication of granzyme B and granulysin in the cell-mediated cytotoxicity response in lichen planus.

METHODS

In situ expression of granzyme B and granulysin was studied by real-time reverse transcriptase polymerase chain reaction in 15 biopsies of lichen planus. The distribution and the phenotype of the inflammatory infiltrate and the expression of granzyme B were studied by immunohistochemistry in seven other biopsies of lichen planus.

RESULTS

Granzyme B and granulysin mRNA expression was one to two hundred times greater than in biopsies of normal skin. Immunohistochemical study revealed that the lymphohistiocytic infiltrate consisted mainly of CD4+ and CD8+ lymphocytes. Granzyme B+ cells were observed close to apoptotic keratinocytes.

CONCLUSION

Our results suggest a central role for cell-mediated cytotoxicity by the granule exocytosis pathway probably because of auto-cytotoxic T-cell clones in the pathogenesis of lichen planus.

TNF- alpha inhibitors

Tumor necrosis-alpha (TNF-alpha) has been implicated in many forms of inflammation and is an end-stage product of the inflammatory cytokine cascade. It is an inducer of inflammation and is involved in many cutaneous and systemic inflammatory diseases. The development of agents that block the effects of TNF-alpha has aided in the treatment of many of these diseases. This article will briefly discuss the production, structure, and administration of the TNF-alpha inhibitors. There will be a focus on the mechanism of action of each of the TNF-alpha inhibitors as well as their benefit in their FDA approved and non FDA approved dermatologic conditions. The side effect profile and monitoring recommendations for these agents will also be discussed.

Histochemical analysis of pathological alterations in oral lichen planus and oral lichenoid lesions

Lichen planus is a dermatologic disease of unknown etiology characterized by keratotic plaques on the skin. Many patients also harbor white lesions of the oral mucosa. The literature contains numerous reports of lichen planus-like lesions evolving in conjunction with the administration of a variety of pharmacologic agents. It is difficult, if not impossible, to distinguish such lesions from one another. The present study evaluated the epithelial and basement membrane thickness, mast cells (intact cells and degranulated cells subepithelially) and the presence or absence of blood vessels in oral lichen planus and oral lichenoid lesions. The evaluation was done using the periodic acid-schiff (PAS) and toluidine blue staining techniques on 20 cases each of oral lichen planus and oral lichenoid lesions and 5 control specimens of normal buccal mucosa. The results showed an increased number of degranulated mast cells in areas of basement membrane degeneration, increased vascularity and increased PAS-positive basement membrane thickness in oral lichen planus as compared with oral lichenoid lesions. Reduced epithelial thickness was found in oral lichen planus. The present study emphasizes the importance of these parameters in differentiating oral lichen planus from oral lichenoid lesions using special staining techniques.

Investigation of functional gene polymorphisms interleukin-1β, interleukin-6, interleukin-10 and tumor necrosis factor in individuals with oral lichen planus

Oral lichen planus (OLP) is a chronic inflammatory oral mucosal disease. There are some studies in the literature demonstrating association between cytokines genes polymorphisms and susceptibility to develop some immune-mediate conditions. The purpose of this study was to investigate cytokine gene polymorphisms in a sample of Brazilian patients with OLP. Fifty-three patients with OLP (mean age = 43.1 years; range 20-68 years) and 53 healthy volunteers (mean age = 42.9 years; range 21-67) were genotyped for IL-1beta +3954 (C/T), IL-6-174 (G/C), IL-10-1082 (G/A) and TNFA-308 (G/A) gene polymorphisms. Statistical analysis was based on the use of logistic regression (P-values below 0.05 were considered as significant). IL-6 and TNFA homozygous genotypes were significantly more often detected in OLP patients. These genotypes were associated with an increased risk of OLP development (OR 6.89 and 13.04, respectively). IL-1beta and IL-10 gene polymorphisms were not related to OLP development. Our findings clearly demonstrate an association between inheritance of IL-6 and TNFA gene polymorphisms and OLP occurrence, thus giving additional support for genetic basis of this disease.

Salivary interleukin-6 and tumor necrosis factor-alpha in patients with recurrent aphthous ulceration

BACKGROUND

Recurrent apthous ulceration (RAU) is a well known oral disease which seems to be mediated principally by the immune system. However, it is still a matter of debate which part of the immune system is implicated in its pathogenesis as a reaction to the still unknown antigen. The aim of this study was to evaluate salivary cytokines, interleukin (IL)-6, and tumor necrosis factor (TNF)-alpha.

METHODS

In 26 patients with minor RAU, age range of 23-49 years (mean 27.3 years), during both the acute phase and remission and in 26 healthy controls, age range of 22-64 years (mean 30.1 years), salivary IL-6 and TNF-alpha levels were determined by use of enzyme-linked immunosorbent assay (ELISA). Statistical analysis was performed by use of descriptive statistics.

RESULTS

Significant differences in salivary TNF-alpha between healthy controls and patients with acute RAU and during the remission period were found (P < 0.001) as well as between patients with acute RAU and those during the remission period (P < 0.001). No differences in salivary IL-6 between all three groups could be found.

CONCLUSIONS

We might conclude that elevated salivary TNF-alpha levels during acute RAU and especially during the remission period are of importance in RAU, whereas salivary IL-6 levels seem not to play a role in the RAU disease.

Expression of TNF-alpha in oral lichen planus treated with fluocinolone acetonide 0.1%

BACKGROUND

Oral lichen planus (OLP) is a common chronic inflammatory disease involving T cells-mediated immunity. Tumor necrosis factor (TNF)-alpha has been reported to be involved in the disease process. The purpose of this study was to investigate the effect of fluocinolone acetonide in orabase (FAO) 0.1% on the expression of TNF-alpha in patients with OLP.

METHODS

Eighteen Thai patients with atrophic or erosive OLP were recruited. Biopsy specimens were taken before and 1 month after treatment with FAO 0.1% and sent for histopathologic examination where they were immunohistochemically stained with antibody to TNF-alpha. Twenty normal mucosa specimens were identically processed. Oral squamous cell carcinoma tissue was used as a positive control for TNF-alpha expression, whereas OLP sections without primary antibody were served as negative control.

RESULTS

Sixteen of 18 cases (88.89%) of OLP exhibited positive staining for TNF-alpha. Most of the TNF-alpha was observed in the mononuclear cells. Ten cases (55.56%) of OLP demonstrated TNF-alpha expression in keratinocytes. The number of mononuclear cells positive for TNF-alpha before the treatment with FAO 0.1% in orabase was statistically higher than that after the treatment (P=0.000) and in the normal mucosa (P=0.000). Moreover, the number of mononuclear cells after treatment with FAO 0.1% in orabase was statistically lower than before the treatment (P=0.000).

CONCLUSION

Our study exhibited that TNF-alpha may be associated with the immunopathogenesis of OLP in Thai patients and FAO 0.1% had an effect on the reduction of TNF-alpha expression.

Levamisole can modulate the serum tumor necrosis factor-alpha level in patients with recurrent aphthous ulcerations

BACKGROUND

Recurrent aphthous ulcerations (RAU) are common oral inflammatory lesions. Tumor necrosis factor (TNF)-alpha is an important inflammatory mediator and a critical cytokine for adequate host defense. Our previous studies have shown that 14-43% and 59-63% of patients in the ulcerative stage of major, minor or herpetiform RAU have significantly higher than normal serum levels of interleukin (IL)-6 and IL-8, respectively. In this study, we examined whether RAU patients in the ulcerative stage had a significantly higher than normal serum level of TNF-alpha and assessed whether treatment with levamisole can modulate serum TNF-alpha levels in RAU patients.

METHODS

This study used a solid phase, two-site sequential chemiluminescent immunometric assay to determine the baseline serum levels of TNF-alpha in 146 patients with RAU, nine patients with traumatic ulcers (TU), and 54 normal control subjects. Fifty-five RAU patients with serum TNF-alpha levels higher than 5.0 pg/ml were treated with levamisole for 0.5-4 months and their serum TNF-alpha levels were measured after treatment.

RESULTS

We found that 29% (42 of 146) RAU patients as well as 39% (24 of 61) major type, 20% (14 of 69) minor type, and 25% (four of 16) herpetiform type RAU patients had a serum level of TNF-alpha greater than the upper normal limit of 7.4 pg/ml. The mean serum level of TNF-alpha in patients with RAU (9.1 +/- 1.0 pg/ml, P < 0.001), major type RAU (11.6 +/- 1.9 pg/ml, P < 0.001), minor type RAU (6.9 +/- 0.9 pg/ml, P < 0.005), or herpetiform type RAU (9.6 +/- 2.7 pg/ml, P < 0.001) was higher than that (3.8 +/- 0.2 pg/ml) in normal control subjects. The mean serum TNF-alpha level was significantly higher in patients with major type RAU than in patients with minor type RAU (P < 0.05) and was significantly higher in major type RAU patients in the exacerbation stage than in the post-exacerbation stage (P < 0.05). In 55 RAU patients with serum TNF-alpha levels higher than 5.0 pg/ml, treatment with levamisole for a period of 0.5-4 months could significantly reduce the serum TNF-alpha level from 16.4 +/- 1.9 to 5.8 +/- 0.6 pg/ml (P < 0.001).

CONCLUSIONS

We conclude that a significantly higher than normal serum level of TNF-alpha can be detected in 20-39% of patients in the ulcerative stage of major, minor or herpetiform RAU. The serum TNF-alpha level may be associated with the severity and the stage of RAU. Levamisole can modulate serum TNF-alpha levels in RAU patients.

Number V Oral lichen planus: clinical features and management

Oral lichen planus (OLP) is a relatively common chronic inflammatory disorder affecting stratified squamous epithelia. Whereas in the majority of instances, cutaneous lesions of lichen planus (LP) are self-limiting and cause itching, oral lesions in OLP are chronic, rarely undergo spontaneous remission, are potentially premalignant and are often a source of morbidity. Current data suggest that OLP is a T cell-mediated autoimmune disease in which auto-cytotoxic CD8+ T cells trigger apoptosis of oral epithelial cells. The characteristic clinical aspects of OLP may be sufficient to make a correct diagnosis if there are classic skin lesions present. An oral biopsy with histopathologic study is recommended to confirm the clinical diagnosis and mainly to exclude dysplasia and malignancy. The most commonly employed and useful agents for the treatment of lichen planus (LP) are topical corticosteroids but other newer agents are available.

"Tien-Hsien liquid" can modulate antigen-stimulated cytokine production by T-cells isolated from patients with recurrent aphthous ulcerations

Recurrent aphthous ulcerations (RAU) represent a common oral mucosal disease with altered humoral and cellular immunities. Tien-Hsien liquid (THL) is an extract of Chinese medicinal herbs with immunomodulating effects. Our previous study found that THL can modulate the antigen-stimulated proliferative response of peripheral blood mononuclear cells and T-cells isolated from RAU patients. In this study, we further tested whether THL can modulate the antigen-stimulated cytokine production by T-cells isolated from RAU patients. To achieve this goal, T-cells isolated from 19 RAU patients were incubated with phytohemagglutinin (PHA), glutaraldehyde-inactivated tetanus toxoid (TT), glucosyltransferase D (GtfD), or antigens of Streptococcus mutans in the presence or absence of THL. The levels of interleukin (IL)-2, interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), IL-6, or IL-10 in the supernatants of T-cell cultures were measured by cytokine enzyme-linked immunosorbent assay (ELISA) kits. We found that THL significantly increased the PHA- or TT-stimulated TNF-alpha, IL-6, and IL-10 production by T-cells isolated from RAU patients. However, THL could also significantly decrease the TT-stimulated IL-2 production, the GtfD-stimulated IL-2, TNF-alpha, IL-6 and IL-10 production, and the S. mutans-stimulated IFN-gamma, TNF-alpha, and IL-10 production by T-cells isolated from RAU patients. These results indicate that THL can modulate the antigen-stimulated cytokine production by T-cells isolated from RAU patients. Because RAU is probably a Thl-mediated disease with elevated levels of IL-2, IFN-gamma, TNF-alpha and IL-6 in either the patient's sera or oral lesions and these increased levels of cytokines can be reduced by THL, we suggest that THL may be a potential immunoceutical agent for treatment of RAU.

The ‐308 Promoter Polymorphism in the Tumour Necrosis Factor Gene in Patients with Lichen Planus

The close chromosomal proximity of major histocompatibility complex and tumour necrosis factor genes may suggest the involvement of the latter in the pathogenesis of immunological diseases associated with HLA antigenes. The major histocompatibility complex antigens may play a certain role in the pathogenesis of lichen planus. Therefore we examined the -308 promoter polymorphism of tumour necrosis factor gene in patients with lichen planus. Sixty-six patients and 66 age- and sex-matched controls participated in the study. Genomic DNA from patients and controls was typed for tumour necrosis factor (-308) polymorphism using an allele-specific polymerase chain reaction. We did not find any correlation between genotype distribution, allele frequency and lichen planus. In our study we failed to observe any association between a genotype and mean level of tumour necrosis factor in plasma of our patients.

Current controversies in oral lichen planus: Report of an international consensus meeting. Part 1. Viral infections and etiopathogenesis

Despite recent advances in understanding the immunopathogenesis of oral lichen planus (LP), the initial triggers of lesion formation and the essential pathogenic pathways are unknown. It is therefore not surprising that the clinical management of oral LP poses considerable difficulties to the dermatologist and the oral physician. A consensus meeting was held in France in March 2003 to discuss the most controversial aspects of oral LP. Part 1 of the meeting report focuses on (1) the relationship between oral LP and viral infection with special emphasis on hepatitis C virus (HCV), and (2) oral LP pathogenesis, in particular the immune mechanisms resulting in lymphocyte infiltration and keratinocyte apoptosis. Part 2 focuses on patient management and therapeutic approaches and includes discussion on malignant transformation of oral LP.

Serum interleukin-8 level is a more sensitive marker than serum interleukin-6 level in monitoring the disease activity of oral lichen planus

BACKGROUND

Oral lichen planus (OLP) is a T-cell-mediated inflammatory disease. Interleukin (IL)-8 is a pro-inflammatory cytokine of host response to injury and inflammation.

OBJECTIVES

To investigate whether serum IL-8 level was a more sensitive marker than serum IL-6 level in monitoring the disease activity of OLP and to assess whether IL-8 was a useful serum marker in evaluating the therapeutic effects of levamisole on OLP patients.

METHODS

In this study, we used a solid phase, two-site sequential chemiluminescent immunometric assay to determine the baseline serum levels of IL-6 and IL-8 in 158 patients with OLP, nine patients with traumatic ulcers (TU) and 54 normal control subjects. Some OLP patients with the serum IL-6 or IL-8 levels higher than the upper limit of normal serum concentration were treated with levamisole for 0.5-6.0 months and their serum IL-6 and IL-8 levels were measured after treatment.

RESULTS

We found that 28% (44 of 158) OLP, 28% (40 of 142) erosive OLP (EOLP), and 25% (four of 16) nonerosive OLP (NEOLP) patients had a serum IL-6 level greater than the upper normal limit of 4.7 pg mL(-1). In contrast, 63% (99 of 158) OLP, 63% (90 of 142) EOLP and 56% (nine of 16) NEOLP patients had a serum IL-8 level greater than the upper normal limit of 8.7 pg mL(-1). In some OLP patients with the serum IL-6 or IL-8 levels higher than the upper limit of normal serum concentration, treatment with levamisole for a period of 0.5-6.0 months could significantly reduce the mean serum IL-6 level from 14.3 +/- 1.9 pg mL(-1) to 3.2 +/- 0.6 pg mL(-1) (P < 0.001) and could significantly reduce the mean serum IL-8 level from 95.8 +/- 17.1 pg mL(-1) to 14.8 +/- 5.8 pg mL(-1) (P < 0.001).

CONCLUSIONS

Because measurement of the serum IL-8 level can detect more OLP patients with an abnormal serum level than measurement of the serum IL-6 level (63% vs. 28%), we conclude that serum IL-8 level is a more sensitive marker than serum IL-6 level in monitoring the disease activity of OLP. Levamisole can modulate both the serum IL-6 and IL-8 levels in OLP patients. IL-8, like IL-6, is also a useful serum marker in evaluating the therapeutic effects of levamisole on OLP patients.

Salivary levels of tumor necrosis factor-alpha in oral lichen planus

OBJECTIVE

Oral lichen planus (OLP) is chronic inflammatory disease of the oral mucosa, presenting in various clinical forms. The etiology of OLP is still unknown but mounting evidence points to the immunologic basis of this disorder.

AIM

Our study was undertaken to quantify the salivary levels of pro-inflammatory tumor necrosis factor-alpha (TNF-alpha) in the reticular and the erosive/atrophic forms of OLP, compared with age-matched healthy control volunteers.

SUBJECTS AND METHODS

Whole saliva from 40 patients with active lesions of OLP, as well as from 20 healthy persons, was investigated for the presence of TNF-alpha by enzyme immunoassay.

RESULTS

Salivary TNF-alpha levels were significantly increased in patients with OLP in comparison with healthy subjects. The presence of TNF-alpha showed positive correlation to clinical forms of OLP, being significantly higher in the erosive/atrophic type than in the reticular type of disease.

CONCLUSION

Saliva provides an ideal medium for the detection of pro-inflammatory markers of the oral cavity. In patients with OLP, TNF-alpha levels in saliva are elevated, correlating with the severity of illness. Salivary TNF-alpha analysis may be a useful diagnostic tool and a potential prognostic marker in OLP.

The role of perforin-mediated apoptosis in lichen planus lesions

Lichen planus is recognized as a T-cell-mediated disease. Histologically, it is characterized by the formation of colloid bodies representing apoptotic keratinocytes. The apoptotic process mediated by CD8(+) cytotoxic T lymphocytes (CTLs) and NK cells mainly involves two distinct pathways: the perforin/granzyme pathway and the Fas/FasL pathway. So far, little is known regarding the role of perforin-mediated apoptosis in lichen planus. In the present study, the expression and distribution of perforin, T and NK cell subsets in the epidermis and dermis of lesional and nonlesional lichen planus skin were studied. Skin biopsy specimens from lesional and nonlesional skin of ten patients with lichen planus and eight healthy persons were analysed by immunohistochemistry. Significant accumulation of T cells, particularly of CD4(+) and CD8(+) subsets, was found in both epidermis and dermis of lichen planus lesions compared with nonlesional and healthy skin. There were no significant differences in the incidence of NK cells (CD16(+) and CD56(+)) between lesional, nonlesional and healthy skin. Perforin expression was significantly upregulated in the epidermis of lichen planus lesions. In conclusion, accumulation of perforin(+) cells in the epidermis of lichen planus lesions suggest a potential role of perforin in the apoptosis of basal keratinocytes.

Histopathology of the teeth in segmental odontomaxillary dysplasia: new findings

Histological examination of the deciduous teeth in two cases of segmental odontomaxillary dysplasia (SOMD) showed fibrous enlargement of the pulps, an irregular pulp/dentine interface displaying many pseudoinclusions and pulp stones. There were tubular defects in the coronal dentine from pulp horn to cusp tip, an irregular tubular structure to the circumpulpal dentine of the apical half, a focally deficient odontoblast layer and widespread external resorption. Together with the clinical features of unilateral maxillary enlargement, upper alveolar expansion in the distal segment, increased spacing and delayed eruption of the deciduous molars and absence of premolar teeth, these histological appearances allow distinction of this condition from fibrous dysplasia (FD), segmental hemifacial hypertrophy (SHH) and regional odontodysplasia (ROD).

Tumor necrosis factor-alpha and interferon-gamma polymorphisms contribute to susceptibility to oral lichen planus

Most lymphocytes in the lamina propria of oral lichen planus (OLP) lesions express and secrete interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha), whereas they do not secret interleukin-4 and -10 or transforming growth factor-beta. We analyzed whether the polymorphisms of several cytokines may influence the susceptibility to OLP. Cytokine typing was performed by a sequence-specific PCR assay. Thirteen cytokine genes with 22 single-nucleotide polymorphisms were studied. IFN-gamma UTR 5644 genotype frequencies showed a significant increase in number of T/T homozygotes in OLP patients compared with controls (40.9 vs. 22.9%; p=0.0022). Moreover, in OLP patients, the frequency of the -308A TNF-alpha allele was higher than in the controls (21.6 vs. 9.3%; p < 0.05) causing a significantly increased frequency of the genotype G/A in OLP (43.2 vs. 14.3%; p=0.0002). Because in patients with mucocutaneous lichen planus (LP), the frequency of the -308A TNF-alpha allele was more than double the values in the pure OLP patients (40.9 vs. 15.1%; p=0.003), the -308G/A TNF-alpha genotype showed a significantly higher frequency in patients with mucocutaneous LP than in patients with pure OLP (81.8 vs. 30.3%, p=0.003). In conclusion, we suggest that genetic polymorphism of the first intron of the promoter gene of IFN-gamma may be an important risk factor to develop oral lesions of LP, whereas an increase in the frequency of -308A TNF-alpha allele may best contribute to the development of additional skin involvement.

Oral lichen planus part I: epidemiology, clinics, etiology, immunopathogeny, and diagnosis

This article presents a review of the literature on oral lichen planus, focusing on important aspects of its epidemiology, etiopathogeny, and clinical manifestations. The oral form is an important clinical presentation of lichen planus. It may precede or accompany the skin lesions, or it may be the only manifestation of the disease. Dermatologists, dentists, otorhinolaryngologists, and other specialists who deal with the oral cavity must be aware of this disease so they can diagnose, treat, and keep these patients under observation.

Mast cells and oral inflammation

Mast cells are mobile granule-containing secretory cells that are distributed preferentially about the microvascular endothelium in oral mucosa and dental pulp. The enzyme profile of mast cells in oral tissues resembles that of skin, with most mast cells expressing the serine proteases tryptase and chymase. Mast cells in oral tissues contain the pro-inflammatory cytokine tumour necrosis factor-alpha in their granules, and release of this promotes leukocyte infiltration during evolving inflammation in several conditions, including lichen planus, gingivitis, pulpitis, and periapical inflammation, through induction of endothelial-leukocyte adhesion molecules. Mast cell synthesis and release of other mediators exerts potent immunoregulatory effects on other cell types, while several T-lymphocyte-derived cytokines influence mast cell migration and mediator release. Mast cell proteases may contribute to alterations in basement membranes in inflammation in the oral cavity, such as the disruptions that allow cytotoxic lymphocytes to enter the epithelium in oral lichen planus. A close relationship exists among mast cells, neural elements, and laminin, and this explains the preferential distribution of mast cells in tissues. Mast cells are responsive to neuropeptides and, through their interaction with neural elements, form a neural immune network with Langerhans cells in mucosal tissues. This facilitates mast cell degranulation in response to a range of immunological and non-immunological stimuli. Because mast cells play a pivotal role in inflammation, therapies that target mast cell functions could have value in the treatment of chronic inflammatory disorders in the oral cavity.

Upregulation of human beta-defensin 2 peptide expression in oral lichen planus, leukoplakia and candidiasis. an immunohistochemical study

Human beta defensin 2 (hBD-2) is a major antimicrobial peptide that is produced by many types of epithelial cells, and is transcriptionally inducible by various proinflammatory agents, such as cytokines and bacteria. Although in vitro studies of the hBDs in oral epithelial cells have been well documented, only little is known about the in vivo pathological state of oral epithelium. We investigated the localization of hBD-2 peptide in tissue sections of oral lichen planus, leukoplakia, candidal leukoplakia and radicular cysts using immunohistochemistry. HBD-2 was stained in both the hyperkeratinized and the granular layers in cases of lichen planus with hyperkeratosis and leukoplakia. Expression in spinous and suprabasal layers was often strong in lichen planus. There were no significant differences in the number of S-100 positive dendritic cells between the widely stained areas and those with limited staining areas in lichen planus. In cases of candidal leukoplakia, the hyphae of candida were mainly detected on the surface of keratinization, which showed only negative or faint staining for hBD-2. These results suggest that hBD-2 is vigorously induced by lichen planus-related inflammation and that it plays an important role in protection from Candida albicans infection; however, it is not a strong chemotactic attractant for Langerhans cells in pathological conditions of oral epithelium.

Levamisole and Chinese medicinal herbs can modulate the serum interleukin-6 level in patients with recurrent aphthous ulcerations

BACKGROUND

Recurrent aphthous ulcerations (RAU) are common oral inflammatory lesions. Interleukin-6 (IL-6) is a pro-inflammatory cytokine that has effects on cellular and humoral immunities. Previous studies have shown that the high serum IL-6 levels in some RAU patients can be reduced by drug treatment. This finding suggests that IL-6 may be a useful marker in evaluating therapeutic effects of RAU.

METHODS

In this study, we used a solid phase, two-site sequential chemiluminescent immunometric assay to determine the baseline serum levels of IL-6 in a group of 228 patients with RAU, erythema multiforme (EM), traumatic ulcers (TU), oral submucous fibrosis (OSF), pemphigus vulgaris (PV), or Sjögren's syndrome (SS), and in 77 normal control subjects. Some RAU patients were treated with levamisole plus Chinese medicinal herbs or levamisole only for 0.5-5 months and their serum IL-6 levels were measured after treatment.

RESULTS

We found that about 99% of the normal control subjects and the patients with EM, TU, or OSF had a serum IL-6 level within the normal limit of 5.0 pg/ml. However, 24% (48/197) RAU patients, 14% (1/7) EM patients, 43% (3/7) PV patients, and 100% (6/6) SS patients had a serum level of IL-6 greater than 5.0 pg/ml. The mean serum level of IL-6 in patients with RAU (3.6 +/- 3.5 pg/ml, P < 0.001), minor type RAU (2.7 +/- 2.0 pg/ml, P < 0.05), major type RAU (5.2 +/- 4.6 pg/ml, P < 0.001), or herpetiform type RAU (4.1 +/- 3.8 pg/ml, P < 0.01) was higher than that in normal control subjects. The mean serum level of IL-6 in major type (P < 0.001) or in herpetiform type RAU patients (P < 0.05) was higher than that in minor type RAU patients. The mean reduction of serum IL-6 level (10.0 +/- 7.1 pg/ml) in RAU patients after treatment with levamisole plus Chinese medicinal herbs was significantly higher than that (5.1 +/- 3.7 pg/ml) in RAU patients after treatment with levamisole only (P < 0.005), suggesting that the combination therapy is superior to the single therapy of levamisole only.

CONCLUSION

We conclude that levamisole and levamisole plus Chinese medicinal herbs can modulate the serum IL-6 level in RAU patients. Although the therapeutic effect of RAU can be assessed by a decrease in the frequency, duration and number of the oral ulcerations, it can also be monitored by a reduction of serum IL-6 level in RAU patients.