Immunohistochemical and serological comparison of idiopathic and hepatitis C virus-associated forms of oral lichen planus

Periodontopathogen profile of healthy and oral lichen planus patients with gingivitis or periodontitis

Oral lichen planus (OLP) is a chronic inflammatory disease that is frequently detected in oral tissues. The aim of our study was to identify the prevalence of the detection of periodontopathogenic microorganisms (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia and Treponema denticola in OLP patients and to compare with this prevalence of periodontopathogenic microorganisms in healthy non-OLP patients. Our study included 27 (18 chronic periodontitis (OLPP) and 9 gingivitis (OLPG)) patients diagnosed with OLP along with 26 (13 chronic periodontitis (HP) and 13 gingivitis (HG)) healthy non-OLP patients. The multiplex polymerase chain reaction (PCR) with subsequent reverse hybridization method (micro-IDent) was used for identifying periodontopathogenic microorganisms present in subgingival plaque samples. The percentages of detection for A. actinomycetemcomitans, P. gingivalis, P. intermedia, T. forsythia and T. denticola in subgingival plaque samples taken from OLP patients (OLPG and OLPP) were 18.5%, 85.1%, 81.4%, 88.8% and 74%, respectively. Meanwhile, in the non-OLP patients (HG and HP), these values were 7.6%, 50%, 46.1%, 73% and 57.7%, respectively. Thus, comparing the non-OLP groups with the OLP groups, the periodontopathogens' percentages of detection in the OLP groups were higher than those in the non-OLP groups. According to our study results, OLP patients have higher levels of infection with A. actinomycetemcomitans, P. gingivalis, P. intermedia, T. forsythia and T. denticola than non-OLP patients. We argue that the high percentages in patients with OLP may help identify the importance of periodontopathogenic microorganisms in the progress of periodontal diseases of OLP.

Hepatitis C virus-host interactions: Etiopathogenesis and therapeutic strategies

Hepatitis C virus (HCV) is a significant health problem facing the world. This virus infects more than 170 million people worldwide and is considered the major cause of both acute and chronic hepatitis. Persons become infected mainly through parenteral exposure to infected material by blood transfusions or injections with nonsterile needles. Although the sexual behavior is considered as a high risk factor for HCV infection, the transmission of HCV infection through sexual means, is less frequently. Currently, the available treatment for patients with chronic HCV infection is interferon based therapies alone or in combination with ribavirin and protease inhibitors. Although a sustained virological response of patients to the applied therapy, a great portion of patients did not show any response. HCV infection is mostly associated with progressive liver diseases including fibrosis, cirrhosis and hepatocellular carcinoma. Although the focus of many patients and clinicians is sometimes limited to that problem, the natural history of HCV infection (HCV) is also associated with the development of several extrahepatic manifestations including dermatologic, rheumatologic, neurologic, and nephrologic complications, diabetes, arterial hypertension, autoantibodies and cryglobulins. Despite the notion that HCV-mediated extrahepatic manifestations are credible, the mechanism of their modulation is not fully described in detail. Therefore, the understanding of the molecular mechanisms of HCV-induced alteration of intracellular signal transduction pathways, during the course of HCV infection, may offer novel therapeutic targets for HCV-associated both hepatic and extrahepatic manifestations. This review will elaborate the etiopathogenesis of HCV-host interactions and summarize the current knowledge of HCV-associated diseases and their possible therapeutic strategies.

Detection of fascin and CCR-7 positive mature dendritic cells in oral lichen planus

BACKGROUND

Dendritic cells (DC) play a crucial role in the pathogenesis of oral lichen planus (OLP) with respect to antigens presented to T cells. We performed immunohistochemical analysis to elucidate the process of activation of DC in OLP.

METHODS

Thirty biopsy specimens were obtained from the patients with OLP. The expressions of CD1a, Langerin, S-100, fascin, chemokine receptor-7 (CCR-7), D2-40, cyclooxygenase-2 (COX-2), and microsomal prostaglandin E synthase-1 (mPGES-1) in DC from OLP and disease free control were investigated using specific antibodies. The distribution and number (1 mm(2)) of DC were assessed in the intra-epithelium and the submucosa specimens. Correlation between the number of DC and epithelium thickness was also determined.

RESULT

Immature DC (Langerin(+), CD1a(+), and S-100(+)) were identified in the epithelia from OLP patients and control, though the numbers of Langerin(+) and CD1a(+) positive cells were decreased in the OLP samples as compared to the control. Mature DC (fascin(+)) were identified in the submucosa specimens, not found in the epithelium from OLP or control. Double immunostaining revealed DC positive for fascin and CCR-7 in the submucosa, which had migrated into D2-40(+) lymph vessels. Furthermore, keratinocytes expressed both Prostaglandin E(2) (PGE(2)) converting enzymes, COX-2, and mPGES-1, indicating PGE(2) synthesis in the epithelial layer of the OLP specimens.

CONCLUSION

Our results indicate that DC change from immature to mature in the epithelium and are then drawn out to the submucosa. We demonstrate that mature DC localized in the submucosa, it consequently migrates into lymph vessels. This maturation process of DC is an important immunopathological feature of OLP.

Oral diseases associated with hepatitis C virus infection. Part 2: lichen planus and other diseases

Some of the most frequent extrahepatic manifestations of hepatitis C virus (HCV) infection involve the oral region predominantly or exclusively. Part 2 of this review discusses the current evidences regarding the association of lichen planus (LP) and other diseases frequently involving the oral cavity with HCV. Epidemiological data suggest that LP may be significantly associated with HCV infections especially in southern Europe and Japan but not in northern Europe. These geographical differences are possibly influenced by immunogenetic factors, the duration of the HCV infection and the design of the published studies. Because of the fact that most of the studies published are retrospective, it is impossible to establish whether the HCV exposure occurred earlier to or after the onset of disease and more prospective studies are clearly warranted. As the virus may replicate in the skin and oral mucosa and HCV-specific T lymphocytes can be found in the oral mucosa of patients with chronic hepatitis C and LP, HCV may be implicated in the pathogenesis of LP. However, little attention has been paid to the variable effect of therapy with interferon-alpha (IFN-alpha), with or without ribavirin for LP. Conversely, it is unlikely that other oral diseases such as oral carcinoma, pemphigus and Behcet disease are triggered by HCV.

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.

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.

Changes in Soluble Adhesion Molecules in Gingival Crevicular Fluid Following Periodontal Surgery

BACKGROUND

Inflammation of periodontal tissues during postoperative wound healing is mediated by cell surface adhesion molecules. Soluble forms of these antigens have also been identified and shown to be important in immunoregulatory processes, but have previously not been investigated during periodontal repair and regeneration. The present study has examined the presence and possible changes in soluble intercellular adhesion molecule-1 (sICAM-1; CD54) and lymphocyte function-associated antigen-3 (sLFA-3; CD58) in gingival crevical fluid (GCF) following periodontal surgery.

METHODS

GCF samples were collected from four groups: 1) a guided tissue regeneration (GTR) test; 2) a GTR control, at least one complete tooth unit away from the periodontal defect; 3) a conventional flap (CF) surgery; and 4) a crown lengthening (CL). Sandwich enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of sICAM-1 and sLFA-3 in the GCF samples.

RESULTS

A marked increase in GCF volumes was found in all sites after surgery, although a persistent increase was associated only with the period of membrane retention at the GTR test sites. In addition, sICAM-1 and sLFA-3 were found in the GCF of healthy as well as diseased sites prior to treatment and the total amounts of both increased transiently following surgical intervention, especially sLFA-3. However, the concentrations of these GCF components, particularly sICAM-1, tended to decrease.

CONCLUSIONS

The temporal decrease in the concentration of sICAM-1 and sLFA-3 in GCF may serve to enhance inflammatory reactions at surgically-treated periodontal sites, thereby limiting repair and regeneration in the periodontium. These soluble adhesion molecules may thereby be of potential therapeutic value and might also be useful markers for monitoring periodontal wound healing.

Hepatitis C virus and lichen planus

Hepatitis C virus (HCV) is an important factor in the development of chronic liver disease and hepatocellular carcinoma. In recent years it has become known that HCV induces various extrahepatic manifestations including mixed cryoglobulinemia, membranoproliferative glomerulonephritis, Sjögren's syndrome, autoimmune thyroiditis, malignant lymphoma, porphyria cutanea tarda and lichen planus. Although the mechanisms of extrahepatic manifestations remain unclear, it is known that interferon (IFN) therapy and coadministration of IFN with ribavirin are effective in promoting the disappearance or alleviation of such extrahepatic lesions, which have tended to be overlooked. The present review focuses on lichen planus, one of the major extrahepatic manifestations.

Oral diseases possibly associated with hepatitis C virus

Morbidity associated with hepatitis C virus (HCV) infection can involve a variety of extrahepatic conditions, including lichen planus (LP) and sialadenitis, predominantly or exclusively involving the oral region, conditions which have been largely neglected in reviews. The literature suggests that HCV-infected patients may frequently have Sjögren-like sialadenitis with mild clinical symptoms, whereas oral LP may be significantly associated with HCV infections in Southern Europe and Japan but not in Northern Europe. These geographical differences could be related to immunogenetic factors such as the HLA-DR6 allele, significantly expressed in Italian patients with OLP and HCV. Analysis of experimental data suggests that HCV could be involved in the pathogenesis of both these diseases. Moreover, parotid lymphoma may arise in patients with sialadenitis, mainly with type II cryoglobulinemia. Little attention has been paid to oral health needs in HCV-infected patients and the variable effect of interferon-alpha therapy on oral tissues. Further research is needed, because of the potentially great influence of oral diseases possibly linked to HCV on the quality of life of millions of patients.

Immunohistochemical study of oral lichen planus associated with hepatitis C virus infection, oral lichenoid contact sensitivity reaction and idiopathic oral lichen planus

OBJECTIVES

Oral lichen planus (OLP) is a common mucocutaneous disorder and might be associated to a possible pathogenic relationship with hepatitis C virus (HCV) infection or hypersensitivity to dental alloy. We examined the clinical and immunohistochemical features of OLP associated with HCV infection (OLP-HCV), oral lichenoid contact sensitivity reaction (OLCSR), and idiopathic oral lichen planus (iOLP). The immunohistochemical expressions of CD4, CD8, B cells, Class II major histocompatibility complex antigen (HLA-DR), S-100, HSP60, Proliferating cell nuclear antigen (PCNA) and Ki-67 were compared to study the pathogenic differences of the three OLP groups.

MATERIALS AND METHODS

Three groups of OLP patients, (I) OLP-HCV patients (n = 17), (2) OLCSR patients (n = 10) and (3) iOLP patients (n = 14) were retrieved from clinical records and tissues examined immunohistochemically by the avidin-biotin-complex technique.

RESULTS

The patients with OLP-HCV showed widespread lesions. The proportion of CD8+ cells was found to be significantly higher in the lamina propria of the OLP-HCV patients and a significantly lower proportion of CD8+ cells of the OLCSR patients was noticed in the epithelium or the connective tissue papillae than in the iOLP patients. There were no significant differences in either the number of CD4+ cells or B cells between the three OLP groups. No significant differences in the number of HLA-DR+ cells were found between the three OLP groups and some OLP-HCV patients showed a significant increase of S-100+ cells in the epithelium compared with iOLP patients. There were no significant differences in either the number of PCNA+ or Ki-67+ cells between the groups. The patients showed similar weak expressions of HSP60 in the three OLP groups.

CONCLUSION

The different distributions of the CD8+ cells that could have functionally different roles might be related to the distinct pathogenic mechanisms in the three OLP groups.

Soluble and cell-associated forms of the adhesion molecule LFA-3 (CD58) are differentially regulated by inflammatory cytokines

The adhesion molecule lymphocyte function-associated antigen 3 (LFA-3) (CD58) is an important regulator of immune cell function which occurs as both surface-associated and 'soluble' forms. This study has investigated the inter-relationship and the effects of cytokines on the expression of LFA-3 isoforms. The surface antigen was found to be relatively unaffected by cytokines, but the release of soluble LFA-3 (sLFA-3) was highly responsive to interleukin 1beta (IL-1beta), interferon gamma (IFN-gamma) and tumour necrosis factor alpha (TNF-alpha). This modulation was cell-specific, particularly with regard to IFN-gamma, which up-regulated sLFA-3 release by A431 cells but down-regulated the release of the soluble form from HEp2 and HepG2 cells. We further demonstrated that LFA-3 is also present in a cytoplasmic 'pool' in each of the cells and, moreover, that cleavage of LFA-3 from the cell surface by phospholipase C resulted in an increase in the levels of the intracellular LFA-3 and replacement of the membrane-associated antigen. These observations suggest that the expression of the surface, soluble and intracellular forms of LFA-3 may be linked by regulatory mechanisms which are likely to exert an important influence on inflammatory interactions.

Histopathological and immunohistochemical study of oral lichen planus-associated HCV infection

Background: In recent years, it has been suggested that oral lichen planus (OLP), a chronic inflammatory keratotic lesion, is related to hepatitis C virus (HCV) infection. Therefore, we evaluated whether the presence or absence of HCV infection caused any histopathological differences in OLP tissues. Methods; The subjects consisted of 31 patients with HCV-related liver disease complicated by OLP (32 OLP lesions) and ten OLP patients without complications due to either HCV infection or liver disease (control). A histopathological evaluation was performed in these patients. In addition, immunostaining was done on nine OLP tissues infected with HCV and on six OLP tissues without HCV infection in order to evaluate lymphocyte subsets (T cells or B cells) infiltrating into topical regions with OLP. Furthermore, the severity of hepatic fibrosis and inflammation was evaluated in liver tissues obtained by liver biopsy from six patients with HCV-related liver disease to evaluate whether there were any relationships between the severity of hepatic fibrosis or inflammation and OLP tissues. Results: There were no significant differences in the histopathological characteristics specific to OLP or in the ratios of T and B cells among infiltrating lymphocytes regardless of the presence or absence of HCV infection. Moreover, there were no certain relationships between the severity of hepatic fibrosis or inflammation and the severity of lymphocytic infiltration in OLP. Conclusions: HCV infection does not appear to influence the histopathological and immunohistochemical features of OLP.

Localized adhesion molecule expression and circulating LFA-3 levels in adult and early onset forms of periodontitis

Because of their importance in mediating cellular interactions in chronic inflammatory diseases, this study has examined the expression of a number of adhesion molecules in adult (n=11), generalized early onset (n=5) and localized early onset (n=2) forms of periodontitis. In comparison with immunostaining profiles of cryostat sections of healthy gingival tissue (n=7), the beta 1 integrins VLA-1, VLA-2 and VLA-4 were found to be up-regulated in periodontitis, with VLA-6 being markedly elevated. Although only small differences were observed in ICAM-1 and LFA-3 expression in the gingival epithelium, there was particularly notable up-regulation of these adhesion molecules within the inflammatory infiltrates of the diseased tissues. However, there were no statistically significant differences between the serum levels of a soluble form of LFA-3 in periodontitis patients (n=47) compared with healthy control subjects (n=40), although the generalized early onset and adult periodontitis groups exhibited wider ranges of circulating LFA-3. These findings show that there is localized modulation of adhesion molecule expression in the chronic inflammatory periodontal diseases studied, but that the levels of LFA-3 in the circulation nevertheless remain unaffected.

LFA-3 (CD58) mediates T-lymphocyte adhesion in chronic inflammatory infiltrates

Previous studies have suggested that LFA-3 has an important role in a number of chronic inflammatory pathologies, although an active role for LFA-3 within in vivo inflammatory reactions has not previously been directly observed in humans. To assess the importance of LFA-3 in this process, this study used an adaptation of the Stamper-Woodruff lymphocyte adhesion assay to measure the binding of exogenous activated lymphocytes to the T-cell-dominated chronic inflammatory infiltrate of oral lichen planus. Antibody blockade experiments showed that anti-LFA-3 monoclonal antibody reduced lymphocyte adhesion by approximately 29%, while anti-ICAM-1 produced a reduction of 26%. These results thus suggest that both LFA-3 and ICAM-1 are likely to mediate cell-cell interactions within lesional tissues in vivo. Moreover, these findings are also the first to directly demonstrate that LFA-3-mediated adhesion, like that of ICAM-1, is functionally important in the molecular pathology of inflammatory mucosal disease.

Hepatitis C virus and oral disease: a critical review

Hepatitis C virus (HCV) infection is widespread with an estimated 3% of the world population being infected. Acute infection is usually mild but chronicity develops in as many as 70% of patients, of whom at least 20% will eventually develop cirrhosis. A further 1-4% of cirrhotic individuals will develop hepatocellular carcinoma. Infection with HCV may have effects on various organs other than the liver. HCV has been causally associated with a remarkable array of extrahepatic manifestations, some of which remain unproven. This review discusses the evidence implicating HCV in the aetiology of two important oral conditions, namely Sjögren's syndrome and lichen planus.