Hypermethylation and low transcription of TLR2 gene in chronic periodontitis.

Periodontitis is an inflammatory disorder characterized by interactions between periodontal pathogens and host's immune response. Epigenetic may contribute to disease development and outcome by influencing the expression of genes involved in the immune response. It has been shown that Toll-like receptors (TLR) play an important role in the response to periodontopathic bacteria. The aim of study was to evaluate the methylation status and the expression of TLR2 gene in gingival samples from individuals with and without periodontitis. DNA was analyzed using the Methyl Profiler DNA Methylation qPCR assay. DNA methylation and transcript levels were evaluated by real-time polymerase chain reaction. The periodontitis group showed a hypermethylated profile and a low expression of gene. Positive correlation between the TLR2 methylation frequency and probing depth was observed. This study gives the first evidence of methylation frequency in inflamed periodontal tissues and of the possible participation of methylation in the development of periodontitis.

Oral cGVHD screening tests in the diagnosis of systemic chronic graft-versus-host disease.

To determine the diagnostic properties of oral manifestations and histological features of graft-versus-host disease (GVHD) screening tests in the diagnosis of systemic chronic graft-versus-host disease (cGVHD). Sixty patients having undergone allogeneic haematopoietic stem cell transplantation were selected. The patients were submitted to a clinical oral examination to assess symptoms and clinical changes in the oral mucosa. Histopathologic analysis of the lower lip oral mucosa (LLOM) and salivary glands (SG) was also performed. Systemic cGVHD was used for a comparison to oral cGVHD. The accuracy of oral cGVHD tests was low for all methods (58.4% and 52.6% for white lesions and white/red lesions, respectively, in the clinical analysis; 50.4% for the presence of oral pain; and 66.8% and 55.1% for LLOM and SG histopathologic tests, respectively). However, the presence of oral pain had good diagnostic properties [specificity: 100.0, 95% confidence interval (CI): 88.0-100.0; positive predictive value (PPV): 100.0, 95% CI: 94.4-100.0; and negative predictive value (NPV): 72.0, 95% CI: 57.3-83.3]. Moreover, SG alterations revealed by the histopathological analysis also exhibited good diagnostic properties (sensitivity: 98.6, 95% CI: 81.5-99.8; PPV: 71.1, 95% CI: 62.1-79.7; NPV: 85.9 95% CI: 32.9-99.4). The clinical severity of oral lesions and histophatological changes in the LLOM did not exhibit adequate diagnostic properties, whereas both oral pain and SG histopathological analysis exhibited adequate properties for the diagnosis of systemic cGVHD. Histological changes in lip oral mucosa and salivary glands together with a clinical manifestation of the disease in the oral mucosa can be useful to determining the systemic cGVHD.

Increased miRNA-146a and miRNA-155 expressions in oral lichen planus.

Oral lichen planus (OLP) is a chronic inflammatory disease T helper 1 lymphocytes (Th1)-mediated. Interferon-gamma (IFN-γ) plays a central role in local immune response in this disease. MicroRNAs (miRNAs) are endogenously expressed non-coding RNAs that have important biological and pathological functions due to their potential mechanism regulating gene expression. Recently, some studies have demonstrated that miRNA-146a and miRNA-155 participate in immune response regulation, and are important in several chronic inflammatory and autoimmune diseases. The purpose of the present study was to investigate the expression of the miRNA-146a and miRNA-155 in 31 OLP lesions compared to normal oral mucosa and blood samples. Quantitative real-time polymerase chain reaction was used to analyze miRNA expressions. Our results showed increased expression of miRNA-146a and miRNA-155 in OLP lesions. In conclusion, these data highlight the possibility of miRNA-146a and miRNA-155 involvement in the regulation of the immune response in OLP.

Investigation of functional IL-10 gene polymorphism and IL-10 levels in acute graft-versus-host disease.

BACKGROUND: Graft-versus-host disease (GVHD) represents a major complication in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients. Although studies have been conducted concerning the investigation of cytokine polymorphisms in the development of acute GVHD (aGVHD), the contribution of recipients and donors as regards cytokine levels has not yet been thoroughly assessed. OBJECTIVE: The aim of this study was to investigate the impact of IL-10 polymorphisms on cytokine levels in blood and saliva, in addition to the occurrence and severity of aGVHD. METHODS: Fifty-eight consecutive allo-HSCT recipients and their donors were included in this prospective study. Saliva and/or blood samples were obtained from recipients and donors to determine IL10 polymorphisms. The IL-10 levels in the blood and saliva were also assessed. The samples were collected from seven days before transplant (day -7) to 100 days after allo-HSCT (day +100), once a week or until the death of recipient. RESULTS: No association was found between recipient and donor IL10 polymorphism and IL-10 levels in the saliva with aGVHD. In contrast, IL-10 levels in the blood were associated with the occurrence of aGVHD. The high producer phenotype in the recipient was also associated with high levels of IL-10 in the blood and saliva. CONCLUSION: Although IL10 polymorphisms were not associated with the occurrence and severity of aGVHD, the genetic background of the recipient did in fact influence the production of the cytokine. Furthermore, as IL-10 levels in the blood were associated with the disease development, this parameter may well be a useful predictor of aGVHD development.