Alteration in peripheral blood mononuclear cell function and serum cytokines in oral lichen planus

Relationship between salivary levels of interleukin-8 and HbA1c in patients with type 2 diabetes

INTRODUCTION

Diabetes mellitus is a metabolic disease, which genetic and environmental factors play a role in its pathogenesis. Cytokines as important elements in the immune system have diverse expressions in different individuals and societies and are effective in the pathogenesis of diabetes. This study investigated the relationship between blood sugar control and salivary levels of interleukin-8 (IL-8) in patients with type 2 diabetes.

METHODS

This cross-sectional study was conducted on 73 subjects (35 diabetic and 38 healthy individuals). Unstimulated saliva samples were collected and the correlation between IL-8, as an inflammatory marker and HbA1c (Haemoglobin A1C) was studied.

RESULTS

The levels of IL-8 and HbA1c were significantly higher in the patient group than control group (p < .001, p < .001, respectively). There was not any relationship between salivary IL-8 levels and glycemic control levels (p = .629). Also, there was no remarkable difference between men and women in terms of the levels of IL-8 and HbA1c saliva (p = .524, p = .998, respectively).

CONCLUSION

Although the salivary IL-8 levels were higher in the diabetic patients, blood sugar control did not significantly affect cytokine concentrations. Increased salivary levels of IL-8 in patients with type 2 diabetes could be a basis for risk assessment, prevention and treatment of diabetes-related complications.

Association of interleukin-8 polymorphism (+ 781 C/T) with the risk of oral Lichen Planus disease

BACKGROUND

Oral Lichen Planus (OLP) is a chronic inflammatory mucosal disease. The pathogenesis of OLP is unknown. The Single Nucleotide Polymorphism (SNP) that occurs in the regulatory position + 781 could affect the expression of interleukin-8. This polymorphism is probably associated with increased serum levels of IL-8. The current study aimed to investigate the genotype and allele frequencies of IL-8( + 781 C/T) in OLP patients and whether it is associated with the severity of OLP disease in an Iranian population.

METHODS

Three milliliters of saliva were taken from 100 patients with OLP and 100 healthy individuals who were matched in age and gender. After DNA extraction from saliva samples of patients and healthy individuals, the genotype of IL-8 at position + 781 is detected using the PCR-RFLP method. The results were analyzed using SPSS software.

RESULTS

Frequency of C/C, T/C, and T/T genotypes at position IL-8 + 781 gene in the patient group were 47%, 41%, and 12%, respectively, and in the control group, were 37%, 42%, and 21%. The difference between the two groups regarding allele frequency distribution was statistically significant (χ² = 3.86, p = 0.049, 95% CI = 0.44-1, OR = 0.66). Our results indicated the significantly higher frequency of the TT genotype in the erosive OLP compared to the nonerosive group (p = 0.03, OR = 0.89, 95% CI = 0.49-1.6).

CONCLUSION

This study depicted the difference in the frequency of SNP IL-8 + 781 C/T allele in the patient and control groups had a significant association with the risk of OLP. In addition, our data revealed that IL-8 + 781 C/T polymorphisms might be associated with the severity of OLP in the Iranian population.

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.

Analysis of Immunologic Function Changes in Lichen Planus After Clinical Treatment

BACKGROUND Lichen planus (LP) is a common chronic superficial skin lesion that causes chronic or sub-acute inflammatory disorders. LP can affect the oral cavity, skin, mucous membrane, and other body parts, and features include repeat attacks and long duration, leading to lower quality of life. This study aimed to analyze the changes of immunologic function before and after treatment of LP. MATERIAL AND METHODS Thirty cutaneous LP patients were selected. Peripheral blood was collected in the morning before and after treatment. Peripheral blood mononuclear cells (PBMCs) were isolated by density gradient method. Flow cytometry was used to detect T cell subpopulation CD4⁺ T cells and CD8⁺ T to calculate CD4⁺ T/CD8⁺ T ratio. Enzyme-linked immunosorbent assay (ELISA) was adopted to detect the helper T-cell (Th) factor IL-2, IFN-γ, IL-4, IL-6, IL-17, and IL-22 levels. RESULTS Compared with before treatment, the expressions of CD4⁺ T cells and CD8⁺ T cells were decreased, while the proportion of CD4⁺ T/CD8⁺ T were significantly elevated after treatment. IL-2 and IFN-γ secretion were markedly increased, whereas IL-4, IL-6, IL-17, and IL-22 were significantly reduced after treatment (P<0.05). CONCLUSIONS LP treatment reduces the distribution of CD4⁺ T cells and CD8⁺ T cells, and promotes the changes of Th1, Th2, and Th17 cytokines secretion.

The Measurement of Serum Tumor Necrosis Factor-alpha Levels in Patients with Lichen Planus

Background:

Lichen planus is a common mucocutaneous inflammatory skin disease with a multifactorial etiology. Cytokines have a key role in its pathogenesis. In our study, we aimed to investigate the relationship between the disease severity and levels of the tumor necrosis factor alpha (TNF-α) cytokine which was considered as a primary cytokine that initiates the cytotoxicity.

Materials and Methods:

A total of 34 patients with lichen planus who were 18 year or older and gender-matched healthy controls were included in the study. Serum TNF-α levels were measured by human TNF-α enzyme-linked immunosorbent assay test kits and the values in the two groups were statistically compared.

Results:

The mean serum TNF-α levels were higher in the patient group than that in the control group. Serum TNF-α levels were not associated with oral mucosal involvement and gender. However, it was observed that the level of TNF-α was higher in older ages, both in patient and in control groups.

Conclusion:

It is thought that TNF-α, a proinflammatory cytokine, may have an important role in the pathogenesis of lichen planus.

The measurement of serum TNF-α levels in patients with lichen planus

BACKGROUND

Lichen planus is a common mucocutaneous inflammatory skin disease with a multifactorial etiology. Cytokines play a key role in lichen planus pathogenesis. This study investigates the relationship between disease severity and levels of tumor necrosis factor-α (TNF-α), which is considered a primary cytokine that initiates cytotoxicity.

MATERIAL AND METHODS

Serum TNF-α levels were compared between a patient group (n = 34) and a control group (n = 20). TNF-α serum levels were measured using human TNF-α Enzyme-Linked Immunosorbent Assay (ELISA) test kits, and the two groups were statistically compared to each other.

RESULTS

Mean serum TNF-α levels were found to be significantly higher in the patient group than in the control group (p < 0.005). However, no significant association was observed between TNF-α levels and oral mucosal involvement (p > 0.005). No relationship was detected between TNF-α levels and patients' sex.

CONCLUSION

It is thought that TNF-α, a proinflammatory cytokine, may play an important role in the pathogenesis of lichen planus. TNF-α may be a simple and effective predictor to illustrate the inflammatory status in patients with lichen planus.

Identifying the association between interleukin-6 and lichen planus: A meta-analysis

Numerous studies have examined the association between interleukin-6 and the pathogenesis of lichen planus (LP)/oral LP (OLP) in various populations; however, there is a lack of systematic analysis. The aim of the present study was to assess this association more precisely, thus a meta-analysis was performed. Case-control studies, which were published up to December 2015, were obtained from PubMed, Embase and the China National Knowledge Infrastructure databases. Data were extracted and pooled mean differences (MDs) with 95% confidence intervals (CIs) were calculated. Ultimately, eight studies were included, comprising 299 LP/OLP cases and 231 control subjects. Overall, the pooled MD for IL-6 was 16.24 (95% CI, 9.84-22.64; I²=99% for heterogeneity). In the subgroup analysis by ethnicity, a significant increase of the IL-6 expression level was identified among Asian individuals, but not in Caucasian individuals. Thus, IL-6 may be significant in the pathogenesis of LP. However, further studies are required to validate these associations.

Salivary levels of interleukin-8 in oral lichen planus and diabetic patients: A biochemical study

BACKGROUND

This study aimed to assess the salivary levels of interleukin-8 (IL-8) in oral lichen planus (OLP) and diabetes mellitus (DM) patients, and OLP + DM patients in comparison with healthy individuals.

MATERIALS AND METHODS

This descriptive cross-sectional study was conducted on 75 patients (30 with OLP, 5 with both OLP and DM, 20 with DM and 20 healthy controls). The salivary levels of IL-8 and fasting blood sugar and 2-h postprandial blood glucose levels were measured in all the subjects. Data were analyzed with one-way ANOVA and post hoc least significant difference tests.

RESULTS

The mean salivary level of IL-8 was the highest in OLP + DM patients, followed by DM, OLP and control groups, respectively. Pair-wise comparisons of the groups revealed significant differences in the salivary levels of IL-8 between OLP and control, DM and control, also OLP + DM patients and control (P < 0.05).

CONCLUSION

The increasing salivary level of IL-8 in the control, OLP, DM, OLP + DM groups, respectively, indicates the role of this inflammatory cytokine in the pathogenesis of OLP and diabetes.

Association of genetic polymorphisms in interferon-γ, interleukin-6 and transforming growth factor-β1 gene with oral lichen planus susceptibility

BACKGROUND

Oral lichen planus (OLP) is a premalignant mucocutaneous disease in which genetic factors and immune responses play a major role. Cytokines play an important role in the pathogenesis and disease progression of OLP. The aim of this study was to investigate the impact of gene polymorphisms of T helper cell subtype Th1 and Th2 cytokines, interferon-gamma (IFN-γ), interleukin-6 (IL-6) and transforming growth factor (TGF)-β1 on OLP susceptibility in a Saudi cohort.

METHODS

Forty two unrelated patients with OLP and 195 healthy controls were genotyped for IFN-γ (874A/T), IL-6 (174G/C) and TGF-β1 (509C/T) polymorphisms.

RESULTS

The frequency of genotype AT of IFN-γ (874A/T) was significantly higher while genotype AA was lower in OLP patients as compared to controls (P < 0.05). The frequency of T containing genotypes (AT + TT) was also higher in OLP patients as compared to that in controls (P = 0.003). The frequencies of allele T was higher while that of allele A lower in patients than the controls however the difference was not statistically significant (P = 0.07). There was no significant difference in the frequencies of alleles and genotypes of IL-6 (174G/C) and TGF-β1 (509C/T) polymorphisms between patient and control groups. These results indicated that genotype AT of IFN-γ (874A/T) polymorphism is associated with OLP risk and genotype AA is protective to OLP. On the other hand the polymorphisms IL-6 (174G/C) and TGF-β1 (509C/T) may not be associated with OLP risk in our population.

CONCLUSION

It is concluded that IFN-γ (874A/T) polymorphism is associated with the susceptibility of OLP, however further studies with large sample size involving different ethnic populations should be conducted to strengthen our results.

Serum level of Interleukin-8 in subjects with diabetes, diabetes plus oral lichen planus, and oral lichen planus: A biochemical study

BACKGROUND

Correlation between diabetes mellitus (DM) and oral lichen planus (OLP) seems probable. Since Interleukin-8 (IL-8) is an important inflammatory mediator involved in both conditions, this study aimed to measure and compare the serum level of IL-8 in DM, OLP, and DM + OLP patients in comparison with healthy individuals.

MATERIALS AND METHODS

This cross sectional study was conducted on 75 patients (30 OLP, 5 OLP and type II DM, 20 type II DM, and 20 healthy controls). Serum levels of IL-8, fasting blood sugar (FBS) and 2-h postprandial blood sugar were measured in the four groups. Data were analyzed using SPSS version 20 by one-way ANOVA and post_hocleast significant difference test.

RESULTS

Type II DM patients with OLP had the highest mean serum level of IL-8 followed by OLP, DM and control groups, respectively. Pairwise comparison of groups revealed significant differences in serum IL-8 between the control and OLP and also control and OLP+DM (P < 0.05) groups. No other significant differences were noted. The mean levels of FBS and 2-h postprandial blood sugar were the highest in OLP+DM patients followed by DM, OLP and control groups, respectively.

CONCLUSION

The ascending trend of serum level of IL-8 in the control, DM, OLP, and DM+OLP patients may indicate the role of this factor in the pathogenesis of DM and OLP. Moreover, it may play a synergistic role in patients suffering from both conditions.

Role of distinct CD4(+) T helper subset in pathogenesis of oral lichen planus

Oral lichen planus (OLP) is one of the most common chronic inflammatory oral mucosal diseases with T-cell-mediated immune pathogenesis. In subepithelial and lamina propria of OLP local lesions, the presence of CD4(+) T helper (CD4(+) Th) cells appeared as the major lymphocytes. These CD4(+) T lymphocytes can differentiate into distinct Th cell types such as Th1, Th2, Treg, Th17, Th22, Th9, and Tfh within the context of certain cytokines environment. Growing evidence indicated that Th1/Th2 imbalance may greatly participate into the cytokine network of OLP immunopathology. In addition, Th1/Th2 imbalance can be regulated by the Treg subset and also greatly influenced by the emerging novel CD4(+) Th subset Th17. Furthermore, the presence of novel subsets Th22, Th9 and Tfh in OLP patients is yet to be clarified. All these Th subsets and their specific cytokines may play a critical role in determining the character, extent and duration of immune responses in OLP pathogenesis. Therefore, we review the roles of distinct CD4(+) Th subsets and their signature cytokines in determining disease severity and susceptibility of OLP and also reveal the novel therapeutic strategies based on T lymphocytes subsets in OLP treatment.

Role of serum interleukin-6 in deciding therapy for multidrug resistant oral lichen planus

Background

Oral lichen planus (OLP) is a T cell mediated immune response. T cells locally present in the involved tissues release cytokines like interleukin-6 (IL-6), which contributes to pathogenesis of OLP. Also IL-6 has been associated with multidrug resistance protein (MRP) expression by keratinocytes. Correspondingly, upregulation of MRP was found in OLP. We conducted this study to evaluate the effects of various drugs on serum IL-6 in OLP; and correlation of these effects with the nature of clinical response and resistance pattern seen in OLP lesions with various therapeutic modalities. Thus we evaluated the role of serum IL-6 in deciding therapy for multidrug resistant OLP.

Material and Methods

Serum IL-6 was evaluated in 42 erosive OLP (EOLP) patients and 10 normal mucosa and 10 oral squamous cell carcinoma cases using ELISA technique. OLP patients were randomly divided into 3 groups of 14 patients each and were subjected to Pimecrolimus local application, oral Mycophenolate Mofetil (MMF) and Methotrexate (MTX) alongwith Pimecrolimus local application. IL-6 levels were evaluated before and after treatment.

Results

Serum IL-6 levels were raised above 3pg/ml in 26.19% erosive OLP (EOLP) cases (mean- 3.72±8.14). EOLP (5%) cases with IL-6 levels above 5pg/ml were resistant in MTX group. However significant decrease in serum IL-6 corresponding with the clinical resolution was seen in MMF group.

Conclusions

Significantly raised IL-6 levels in EOLP reflect the chronic inflammatory nature of the disease. As serum IL-6 levels significantly decreased in MMF group, correspondingly no resistance to treatment was noted. However with MTX there was no significant decrease in IL-6 and resistance to treatment was noted in some, especially plaque type lesions. Thus IL-6 can be a possible biomarker in deciding the best possible therapy for treatment resistant OLP.

Key words:Lichen planus, biological markers, cytokines, enzyme-linked immunosorbent assay, immunosuppressive agents.

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.

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.

Oral lichen planus may enhance the expression of Th17-associated cytokines in local lesions of chronic periodontitis

OBJECTIVES

This study aims to compare the expression levels of interleukin (IL)-17 and IL-23 in local periodontal tissues from patients with both chronic periodontitis and oral lichen planus (CP-OLP), patients with chronic periodontitis (CP) only, patients with oral lichen planus (OLP) only, and healthy controls (HC).

MATERIALS AND METHODS

The periodontal tissues were collected from 15 CP-OLP patients, 15 CP patients, 15 OLP patients, and 10 healthy controls. Immunohistochemistry (IHC) and real-time quantitative PCR (qPCR) was performed to investigate the protein and mRNA expression level of IL-17 and IL-23 in periodontal lesions from these four groups.

RESULTS

IHC statistical analysis showed that the expression level of IL-17- and IL-23p19-positive cells significantly increased in CP-OLP group compared with that in CP (P < 0.01) and OLP groups (P < 0.05), showing intense staining reaction in local lamina propria lesions. Meanwhile, qPCR result showed higher IL-17 mRNA level in CP-OLP compared with that in CP and OLP groups and demonstrated a significant increase than OLP group (P < 0.05). Moreover, it was found that IL-17 mRNA expression level in erosive CP-OLP patients was significantly correlated with probing depth and attachment loss (P < 0.05).

CONCLUSIONS

This study indicated that there was an increased expression level of IL-17 and IL-23 in periodontal tissues from periodontitis patients with oral lichen planus, which might aggravate the inflammatory response in local lesions.

CLINICAL RELEVANCE

Oral lichen planus and chronic periodontitis may have interaction in disease pathogenesis, while IL-17 detection in local lesions may be helpful in identifying the disease severity in periodontitis patients with oral lichen planus.

Interferon-γ and interleukin-4 detected in serum and saliva from patients with oral lichen planus

Our previous salivary study had demonstrated an apparent T helper 2 (Th2)-predominance in saliva of oral lichen planus (OLP) patients and suggested a potential of salivary interleukin-4 (IL-4) as a biomarker for monitoring disease severity. To further determine the consistency of Th1/Th2 bias of OLP, this study investigated the expression profile of interferon-γ (IFN-γ) and IL-4 in serum and the relationship of the serum levels of these cytokines with their saliva partners. Sixty ethnic Chinese patients with OLP (40 of the erythematous/ulcerative form and 20 of the reticular form) were recruited for this study, with 40 age–sex-matched healthy volunteers as control group. IFN-γ and IL-4 levels in serum and paired saliva samples were screened by enzyme-linked immunosorbent assay. OLP patient showed a low-level IFN-γ but high-level IL-4 expression profile in both serum and saliva, with a lower IFN-γ/IL-4 ratio. Serum IL-4 level in the erythematous/ulcerative group was significantly higher than that in the reticular group. Serum levels of IFN-γ and IL-4 were significantly and positively correlated with their saliva partners. These results provided more evidence for Th2 cytokine-predominant immune imbalance in OLP, as well as the potential of IL-4 as the biomarker for monitoring severity of OLP.

Reduced immune responses to purified protein derivative and Candida albicans in oral lichen planus

BACKGROUND

Impairment of cellular immunity is reported in lichen planus, an autoimmune disease affecting mucosae and skin. Our aim was to investigate immune responses directed against a set of microbial antigens in patients with oral lichen planus and in matched controls.

METHODS

Venous blood was obtained, and the mononuclear cells were enriched by density gradient centrifugation. The proliferation of peripheral blood mononuclear cells was assessed, following stimulation with purified protein derivative (PPD), Candida albicans, phytohemagglutinin or when cells were left unstimulated, after three or six days of cell culture. The production of interleukin-1ß (IL-1ß), IL-2, IL-4, IL-5, IL-6, IL-10, IL-12, IL-13, IL-17, interferon-γ (IFN-γ), tumour necrosis factor-α (TNF-α), G-CSF, GM-CSF, MCP-1, MIP-ß was assessed in supernatants using the Bio-plex(®) assay and was complemented with ELISA for selected cytokines.

RESULTS

Patients with oral lichen planus demonstrated reduced proliferative responses against PPD (P < 0.05) and C. albicans (P < 0.05). The majority of investigated cytokines, including the pro-inflammatory, IFN-γ and TNF-α were expressed at reduced levels in PPD-stimulated supernatants from patients with oral lichen planus.

CONCLUSIONS

Collectively, the findings suggested that memory lymphocytes from patients with oral lichen planus (OLP) may have an impaired functional ability to react against certain recall antigens, as part of a generalized response, which may reflect immune regulatory processes. Further studies are needed to clarify the mechanisms of down-regulation in OLP pathogenesis and progression.

Proliferation and apoptosis of peripheral blood mononuclear cells in patients with oral lichen planus

Oral lichen planus (OLP) is generally accepted to be a T cell-mediated chronic inflammatory disease with an unclear pathogenesis. There have been numerous studies on the proliferation and apoptosis of T cells in situ. In contrast, research on the proliferation and apoptosis of peripheral blood mononuclear cells (PBMCs) in patients with OLP is rare. The aim of the present study was to investigate the proliferation and apoptosis of PBMCs in patients with OLP. PBMCs were isolated from 20 patients with reticular OLP, 20 patients with atrophic-erosive OLP, and 20 healthy volunteers. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl-2,5-tetrazolium bromide assays were performed to investigate the proliferation of PBMCs, and caspase-3 colorimetric assays were performed to investigate the apoptosis of PBMCs. The proliferation rate of PBMCs in atrophic-erosive OLP subjects was significantly higher than that in both healthy (P < 0.05) and reticular OLP (P < 0.05) subjects. In contrast, the proliferation rate of PBMCs in reticular OLP subjects was significantly lower than that in healthy subjects (P < 0.05). The apoptosis rates of PBMCs in OLP subjects (P < 0.05) and atrophic-erosive OLP subjects (P < 0.05) were significantly lower than the apoptosis rate in the healthy group. Our findings reinforce the view that T cell-mediated immune responses play a critical role in the pathogenesis of OLP. It can reasonably be concluded that these abnormalities are linked to the presence of inflammatory infiltrates.

Levels of salivary IFN-gamma, TNF-alfa, and TNF receptor-2 as prognostic markers in (erosive) oral lichen planus

To explore the feasibility of detecting salivary levels of IFN-γ, TNF-α, and sTNFR-2 from erosive oral lichen planus (ELP) patients for clinical application, 20 ELP patients were enrolled in the study as were 20 age-sex-matched controls. From all subjects, saliva level of the tested biomarkers was determined by ELISA. Salivary profiles were assessed in ELP patients by ELISA after being treated with prednisone. A significantly higher level of IFN-γ (P ≤ .01), TNF-α (P ≤ .0001), and sTNFR-2 (P ≤ .01) was detected in ELP patients before treatment than in controls. Following treatment, the salivary levels of IFN-γ (P ≤ .01), TNF-α (P ≤ .05), and sTNFR-2 (P ≤ .01) decreased significantly when compared to their pretreatment levels. This study demonstrated that salivary IFN-γ, TNF-α, and sTNFR-2 can be detectable in ELP patients and decreased significantly after treatment with prednisone, which may reveal the possibility of using these disease-related biomarkers in diagnosis and monitoring.

Association of interleukin-8 gene polymorphisms and haplotypes with oral lichen planus in a Chinese population

Interleukin-8 (IL-8), a CXC chemokine with multiple biological functions, plays an important role in the pathogenesis of oral lichen planus (OLP). The aim of this study was to investigate the association of single nucleotide polymorphisms (SNPs) of IL-8 gene with OLP in a Chinese population. Four SNPs of the IL-8 gene at positions -845 T/C (rs2227532), -738 T/A, -251 A/T (rs4073) and +781 C/T (rs2227306) were analyzed in 109 patients with OLP and 101 normal controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The data revealed that the -251 AA genotype and -251 A allele frequency was significantly lower in the erosive OLP (eOLP) group than in the control group (P = 0.012 and P = 0.031, respectively). Haplotype analysis revealed that the -251 A/+781 C haplotype frequency was lower in the eOLP group than in the control group (P = 0.029) while the -251 T/+781 C haplotype frequency was higher in the eOLP patients than in the healthy controls (P = 0.028). The study suggests that the IL-8 polymorphisms may be associated with the severity of OLP in this Chinese cohort.

Mannose-binding lectin gene (MBL-2) polymorphism in oral lichen planus

TNF-α may be associated with the etiopathogenesis of oral lichen planus (OLP), and it has been suggested that polymorphism of mannose-binding lectin (MBL) increases the in vitro production of TNF- α. The aim of the present study was to assess the relevance of genetic diversity of MBL in OLP. The study sample comprised 90 individuals, 45 OLP patients and 45 healthy volunteers. MBL-2 gene was amplified using real-time PCR. Frequency of A/A genotype was 55.6% in OLP and 53.3% in healthy volunteers. Likewise, A/0 heterozygote genotype was found in 42.2% and 35.6%; 2.2% and 11.1%, had the recessive 0/0 genotype respectively. Frequencies of the "A" and "0" alleles were 77% and 23% in the OLP group and 71.2% in control group. There were no statistically significant differences regarding genotype frequency (p = 0.546) or allele frequency (p = 0.497). In conclusion, no significant association was found between polymorphism of MBL-2 gene and OLP.

Cytokine gene polymorphisms in hepatitis C virus-related oral lichen planus

Cytokine polymorphisms may influence both the risk of developing oral lichen planus (OLP) and the outcome of hepatitis C virus (HCV)-infected patients and OLP has been frequently associated with HCV infection. The aim of the present study was to analyse whether cytokine polymorphisms may influence the susceptibility to HCV-related OLP. Thirty-five patients with OLP and chronic HCV infection (OLP-HCV+ve) took part in the study. As controls, 44 patients with OLP but without HCV (OLP-HCV-ve) infection and 140 healthy donors were studied. Thirteen cytokine genes with 22 single nucleotide polymorphisms (SNP) were studied. IFN-gamma UTR 5644 genotype frequencies showed an increase in number of A/T heterozygote in OLP-HCV+ve patients compared with OLP-HCV-ve that approached the statistical significance [P = 0.03, P-corrected (PC) = 0.66]. Contrarily, in OLP-HCV+ve patients, the frequency of genotype -308 G/A of the TNF-alpha was decreased, whereas the genotype -308 G/G was increased compared with OLP-HCV-ve (P = 0.0005, PC = 0.011 and P = 0.0016, PC = 0.0352, respectively). OLP patients with and without HCV infection showed a different genetic cytokine background suggesting distinct pathogenetic mechanisms.

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.

Th1/Th2 cytokine ratio in tissue transudates from patients with oral lichen planus

OBJECTIVE

The characteristics of oral lichen planus (OLP) provoke investigators to explore possible biomarkers by which to monitor disease activity and therapeutic efficacy. Oral fluids may provide an accessible medium for analysis of such biomarkers. Previous studies have shown that activation of nuclear factor-kappa B (NF-kappa B) plays an important role in the pathogenesis of oral lichen planus (OLP), which is a chronic inflammatory disorder mediated by T cells. Prior to the present investigation, reports of the levels of NF-kappa B and its dependent cytokines in oral fluids have not been forthcoming. The purpose of this study was to detect the level of NF-kappa B dependent cytokines, TNF-alpha, IL-1-alpha, IL-6, and IL-8 in tissue transudates directly from lesions of OLP, and explore the feasibility of the data for clinical application.

STUDY DESIGN

Thirteen definitively diagnosed OLP subjects were enrolled in the study as were 13 age-sex matched controls. In each subject, lesion tissue transudates (TTs) were collected by a novel collection technique with a filter paper. The level of cytokines, TNF-alpha, IL-1-alpha, IL-6, and IL-8 in three types of oral fluids were determined by ELISA.

RESULTS

In the tissue transudate(TT), there were significantly higher level of cytokines TNF-alpha, IL-1-alpha, IL-6, and IL-8 detected in OLP patients than in controls: (TT: 40.0 +/- 9.8 versus 4.5 +/- 0.7, 710 +/- 114 versus 305 +/- 78, 150 +/- 25 versus 1.7 +/- 0.5, 2800 +/- 260 versus 1450 +/- 130, P < .0001; unit: pg/mL).

CONCLUSIONS

These results indicate that NF-kappa B dependent inflammatory cytokines may be detected at increased levels in oral lesion tissue transudates which may have diagnostic and prognostic potentials for monitoring disease activity and making therapeutic decisions in patients with OLP.

Cytokine alterations in lichen sclerosus: an immunohistochemical study

BACKGROUND

Although the histology of lichen sclerosus is characteristic, the precise nature of the inflammatory changes and the signals provoking them is uncertain.

OBJECTIVES

To delineate the inflammatory changes in lichen sclerosus more accurately by studying cytokine changes.

METHODS

An immunohistochemical study of 12 specimens of genital lichen sclerosus and one specimen of extragenital lichen sclerosus was undertaken using monoclonal antibodies to interferon (IFN)-gamma, IFN-gamma receptor, tumour necrosis factor (TNF)-alpha, interleukin (IL)-1alpha, IL-2 receptor (CD25), intercellular adhesion molecule-1 (ICAM-1) and its ligand CD11a. Control specimens were seven specimens of normal vulva obtained during gynaecological procedures, three specimens of normal skin, adjacent uninvolved thigh from three of the patients with lichen sclerosus, five specimens of nonvulval psoriasis, four specimens of nonvulval lichen planus and two specimens from chronic wounds.

RESULTS

The lichen sclerosus specimens demonstrated slightly increased staining for IFN-gamma within the epidermis compared with the normal vulva and nonvulval skin. There was increased dermal staining for IFN-gamma both within the pale zone of the upper dermis and within the inflammatory zone below this. We confirmed our previous demonstration that in lichen sclerosus HLA-DR immunostaining is increased in association with vascular endothelium, the inflammatory cell infiltrate and around the keratinocytes. The areas of the epidermis with the strongest immunostaining for HLA-DR generally also had the strongest staining for IFN-gamma. In the lichen sclerosus specimens the zone of inflammation also demonstrated increased immunostaining for TNF-alpha, IL-1alpha, IFN-gamma receptor, CD25, CD11a and ICAM-1 while the zone of sclerosus demonstrated a smaller increase in immunostaining for IFN-gamma receptor, TNF-alpha, CD11a and ICAM-1, and the epidermis demonstrated increased staining for ICAM-1.

CONCLUSIONS

The increased staining for IFN-gamma, TNF-alpha, IL-1alpha, IFN-gamma receptor, CD25, CD11a and ICAM-1 suggest that the cytokine response in lichen sclerosus shares characteristics of the cytokine response in lichen planus and chronic wounds.

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.

A comparison of the pro-inflammatory, NF-kappaB-dependent cytokines: TNF-alpha, IL-1-alpha, IL-6, and IL-8 in different oral fluids from oral lichen planus patients

To explore the feasibility of detection of the level of NF-kappaB-dependent cytokines in oral fluids from patient with oral lichen planus (OLP) for clinical application, 13 OLP subjects were enrolled in the study as were 13 age-sex-matched controls. In each subject, the whole unstimulated saliva (WUS), mixture of saliva and isotonic saline oral rinse (Saliva-NaCl), and lesion tissue transudates (TT) were collected by standard techniques. The level of cytokines, TNF-alpha, IL-1-alpha, IL-6, and IL-8 in three types of oral fluids was determined by ELISA. In the three types of oral fluids, a significantly higher level of these cytokines was detected in OLP patients than in normal controls. These results indicate that NF-kappaB-dependent inflammatory cytokines may be detected at increased levels in certain oral fluids which may have diagnostic and prognostic potential for monitoring disease activity and making therapeutic decisions in patients with OLP.

Oral and serum IL-6 levels in oral lichen planus patients

OBJECTIVE

The purpose of this study was to compare IL-6 levels in oral exfoliated mucosal cell samples and in serum in subjects with oral lichen planus versus controls. Study design Ten patients with ulcerative OLP, 10 with reticular OLP, and 10 control subjects were recruited at a University Oral Medicine Clinic. Using smear tissue culture brushes, oral samples were collected from lesional sites for OLP patients and from buccal mucosa for controls into vials with 300 muL PBS. After centrifugation, the supernatants were aspirated for cytokine ELISA assay and protein assay. Venous blood was processed to serum for ELISA assay. Oral IL-6 was expressed as both pg/mL and pg/mug protein, and serum IL-6 was expressed as pg/mL.

RESULTS

The mean oral IL-6 levels were higher in the ulcerative OLP group (11.19 +/- 5.34 pg/mL) than in the reticular OLP (1.05 +/- 0.34 pg/mL) and control (0.52 +/- 0.29 pg/mL) groups. There were significant differences between ulcerative OLP and reticular OLP groups (P < .039), and between ulcerative OLP and control groups (P < .009). After the standardization of IL-6 concentration by protein, a significant difference in IL-6 concentration was shown only between the ulcerative OLP (0.0245 +/- 0.0121 pg/mug protein) and control (0.0023 +/- 0.0012 pg/mug protein) groups (P < .029). Similarly, the ulcerative OLP group showed a significantly higher serum IL-6 level than the control group (P < .021).

CONCLUSION

Both oral and serum IL-6 levels were higher in patients with ulcerative OLP. An oral exfoliated cell technique may be a useful and sensitive method to measure IL-6 in patients with OLP as it provided results consistent with those found in peripheral blood.

Immune activation and chronic inflammation as the cause of malignancy in oral lichen planus: is there any evidence ?

The association of chronic inflammation with a variety of epithelial malignancies has been recognised for centuries. Well established examples include, among many others, oesophageal adenocarcinoma associated with chronic oesophagitis and bowel cancer associated with chronic inflammatory bowel diseases. By now no data, other than clinical observation, have been available in understanding the pathogenesis of these inflammation-related tumours. However, recent molecular studies on the relationship between solid malignancies and the surrounding stroma have given new insights. There is now enough evidence to accept that the chronic inflammatory process per se is able to provide a cytokine-based microenvironment which is able to influence cell survival, growth, proliferation, differentiation and movement, hence contributing to cancer initiation, progression, invasion and metastasis. Here it is discussed whether also oral lichen planus (OLP), being a chronic inflammatory autoimmune disease which has been clinically associated with development of oral squamous cell carcinoma, might be categorised among these disorders. With this aim, we critically reviewed and detailed the presence, in OLP subepithelial infiltrate, of inflammatory cells and cytokine networks that might act to promote squamous tumorigenesis.

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.

Serum interleukin-6 level is a useful marker in evaluating therapeutic effects of levamisole and Chinese medicinal herbs on patients with oral lichen planus

BACKGROUND

Oral lichen planus (OLP) is a T cell-mediated inflammatory disease. Interleukin-6 (IL-6) is a pro-inflammatory cytokine that has effects on cellular and humoral immunities. Previous studies have shown that keratinocytes and tissue-infiltrating mononuclear cells from OLP lesions can secrete IL-6. In some OLP patients, the high serum IL-6 levels are reduced after treatment, suggesting that IL-6 may be a useful marker in evaluating therapeutic effects and in monitoring the disease status of OLP.

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 180 patients with erosive OLP (EOLP), nonerosive OLP (NEOLP), 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 OLP patients were treated with levamisole plus Chinese medicinal herbs or levamisole only for 0.5-5.5 months and their serum IL-6 levels were measured after treatment.

RESULTS

We found that approximately 99% of the normal control subjects and the patients with EM, TU, or OSF had a normal serum IL-6 level less than 5.0 pg/ml. However, 15% (22/149) OLP patients, 15% (20/136) EOLP patients, 20% (5/25) major type EOLP patients, 14% (15/111) minor type EOLP patients, 15% (2/13) NEOLP patients, 14% (1/7) EM patients, 43% (3/7) PV patients, and 100% (6/6) SS patients had a serum IL-6 level greater than 5.0 pg/ml. The mean serum IL-6 level in patients with OLP (3.4 +/- 3.1 pg/ml, P < 0.001), EOLP (3.4 +/- 3.2 pg/ml, P < 0.001), major type EOLP (4.9 +/- 3.5 pg/ml, P < 0.001), minor type EOLP (3.0 +/- 3.0 pg/ml, P < 0.01), or NEOLP (4.2 +/- 1.5 pg/ml, P < 0.001) was significantly higher than that in normal control subjects (2.0 +/- 1.5 pg/ml). A significant difference in the mean serum IL-6 level was also found between major type and minor type EOLP patients (P < 0.01). The mean reduction of serum IL-6 level in OLP patients treated with levamisole plus Chinese medicinal herbs was significantly higher (7.4 +/- 4.7 pg/ml) than that in OLP patients treated with levamisole only (3.8 +/- 2.3 pg/ml, P < 0.05), suggesting that the combination therapy was superior to levamisole only.

CONCLUSION

We conclude that levamisole and levamisole plus Chinese medicinal herbs can modulate the serum IL-6 level in OLP patients. IL-6 may be a useful marker in evaluating therapeutic effects and in monitoring the disease status of OLP.

Reduced in vivo cell-mediated immune responses to mumps, tuberculin, and streptokinase/streptodornase but not to Candida albicans in oral lichen planus

Oral lichen planus is considered to be a T-cell-mediated disease. The purpose of this study was to investigate the capacity of T-lymphocytes in oral lichen planus patients to respond to a number of commonly encountered environmental antigens in vivo. To do this, we assessed dermal delayed-type hypersensitivity responses to mumps, streptokinase/streptodornase, Candida albicans, and purified protein derivative of tuberculin (PPD) in 17 oral lichen planus patients and in matched controls. Reduced induration in response toward mumps, PPD, and streptokinase/streptodornase was demonstrated in oral lichen planus patients compared with controls. In addition, the total sum of induration diameters was decreased in the patients. However, C. albicans stimulation resulted in similar levels of response in both groups. The differences in induration size between matched patients and controls for mumps and PPD were thus significantly greater than the corresponding differences for the C. albicans antigen. This suggests that a selective difference in the response to these antigens exists in oral lichen planus patients. The results may point to a loss of memory T-helper function to infrequently encountered environmental antigens, represented by mumps, PPD, and streptokinase/streptodornase, contrarily to memory function to common antigens (C. albicans), which seem to be unaffected.

Update on oral lichen planus: etiopathogenesis and management

Lichen planus (LP) is a relatively common disorder of the stratified squamous epithelia, which is, in many ways, an enigma. This paper is the consensus outcome of a workshop held in Switzerland in 1995, involving a selection of clinicians and scientists with an interest in the condition and its management. The oral (OLP) eruptions usually have a distinct clinical morphology and characteristic distribution, but OLP may also present a confusing array of patterns and forms, and other disorders may clinically simulate OLP. Lesions may affect other mucosae and/or skin. Lichen planus is probably of multifactorial origin, sometimes induced by drugs or dental materials, often idiopathic, and with an immunopathogenesis involving T-cells in particular. The etiopathogenesis appears to be complex, with interactions between and among genetic, environmental, and lifestyle factors, but much has now been clarified about the mechanisms involved, and interesting new associations, such as with liver disease, have emerged. The management of lichen planus is still not totally satisfactory, and there is as yet no definitive treatment, but there have been advances in the control of the condition. There is no curative treatment available; immunomodulation, however, can control the condition. Based on the observed increased risk of malignant development, OLP patients should be offered regular follow-up examination from two to four times annually and asked to report any changes in their lesions and/or symptoms. Follow-up may be particularly important in patients with atrophic/ulcerative/erosive affections of the tongue, the gingiva, or the buccal mucosa. Much more research is required into the genetic and environmental aspects of lichen planus, into the premalignant potential, and into the possible associations with chronic liver, and other disorders. More clinical studies are required into the possible efficacy of immunomodulatory drugs such as pentoxifylline and thalidomide.

Immunopathogenesis of oral lichen planus and recurrent aphthous stomatitis

Oral mucosal bullous/desquamative/ulcerative diseases involve immunopathological mechanisms that account for loss of adhesion between contiguous keratinocytes or to structures within the basal lamina. Some are antibody mediated, in which specific adhesion molecules of the desmosome, hemidesmosome, and basement membrane become antigenic targets. Oral lichen planus and recurrent apthous ulcers, although manifesting disparate clinical appearances and natural history, share immunopathological features that involve T cell-mediated immunity. Although the antigens, haptens, or autoantigens are not usually apparent, current research poses the hypothesis that both of these common oral mucosal diseases are a delayed-type hypersensitivity or cell-mediated response to an antigenic stimulus residing within the epithelium. This article reviews the research evidence for this hypothesis.