The human microbiome in immunobullous disorders and lichen planus.

For several decades, there has been a significant growth in the incidence of autoimmune diseases. Studies indicate that genetic factors may not be the only trigger for disease development and that dysbiosis of the microbiome may be another mechanism involved in the pathogenesis of autoimmune diseases. The role of the microbiome in the development of common skin disorders such as psoriasis, atopic dermatitis, acne and rosacea is increasingly well understood. However, few studies have focused on lichen planus and the rare acquired immunobullous diseases, both mucocutaneous groups of disorders linked to skin, oral and gut microbiomes. This review provides an insight into the current understanding of how the microbiome may contribute to the development of autoimmunity and to the maintenance and exacerbation of acquired immunobullous and lichenoid diseases. These mechanisms may have implications for future preventive and therapeutic approaches.

Study of virulence factor of Candida species in oral lesions and its association with potentially malignant and malignant lesions.

OBJECTIVE: The aim of this study was to explore the association between malignant and premalignant lesions and the virulence factor profile of Candida spp. recovered from different oral lesions. DESIGN: Candida spp. isolated from malignant lesions (squamous cell carcinoma, OC, n = 25), atypical lichen planus (AL, n = 11), chronic candidiasis (CC, n = 25), and asymptomatic carriers (WI, n = 15, control strains.) Isolates were identified in chromogenic medium, colony morphology and biochemical tests. The lipolytic and proteinase activity was determined on supplemented agar with olive oil and BSA, respectively. The biofilm formation with XTT reduction assay and cellular surface hydrophobicity (CSH) by water-hydrocarbon method were performed. RESULTS: All isolates recovered from oral lesions produced the four virulence factors studied with significantly higher levels than in WI isolates. Interestingly, lipolytic activity was absent in WI isolates. The proteolytic activity was similar in AL and OC isolates. OC isolates showed significantly higher CSH values than other clinical isolates. Non-albicans species showed higher biofilm formation than C.albicans (P = 0.03.) There were no significant differences in virulence factors among species. A strong positive correlation was found between proteinase and lipase activity (r = 0.90, P < 0.0001), and between hydrophobicity and biofilm (R = 0.81, P < 0.0001.) CONCLUSIONS: Our results indicate that OC Candida isolates exhibited a significant higher attributes of virulence than other lesions fungus isolates, providing evidence about the association between Candida pathogenicity and lesions severity.

In Situ Detection of Bacteria within Paraffin-embedded Tissues Using a Digoxin-labeled DNA Probe Targeting 16S rRNA.

The presence of bacteria within the pocket epithelium and underlying connective tissue in gingival biopsies from patients with periodontitis has been reported using various methods, including electron microscopy, immunohistochemistry or immunofluorescence using bacteria-specific antibodies, and fluorescent in situ hybridization (FISH) using a fluorescence-labeled oligonucleotide probe. Nevertheless, these methods are not widely used due to technical limitation or difficulties. Here a method to localize bacteria within paraffin-embedded tissues using DIG-labeled DNA probes has been introduced. The paraffin-embedded tissues are the most common form of biopsy tissues available from pathology banks. Bacteria can be detected either in a species-specific or universal manner. Bacterial signals are detected as either discrete forms (coccus, rod, fusiform, and hairy form) of bacteria or dispersed forms. The technique allows other histological information to be obtained: the epithelia, connective tissue, inflammatory infiltrates, and blood vessels are well distinguished. This method can be used to study the role of bacteria in various diseases, such as periodontitis, cancers, and inflammatory immune diseases.

Oral lichen planus and hepatitis C virus (HCV) infection: is there a relationship? A report of 10 cases.

Ten patients are reported suffering from oral lichen planus (OLP) associated with chronic liver diseases linked to HCV. All patients were affected by varieties of erosive oral lichen planus. In six of these 10 patients the diagnosis of HCV was made as a result of the OLP diagnosis and four of them had unknown, but severe, chronic liver disease. These preliminary data support the possible existence of a relationship between oral erosive lichen planus and HCV infection.

Lichen planus and hepatitis C virus--related chronic active hepatitis.

BACKGROUND AND DESIGN: An increased prevalence of chronic liver disease has been reported in patients with lichen planus (LP). We report six cases of LP associated with chronic active hepatitis and actively replicating hepatitis C virus (HCV). RESULTS: We studied six patients (three men and three women; mean age, 61 years; age range, 47 to 70 years) with various forms (cutaneous and/or mucosal) of LP and abnormal liver test results. Four patients had severe mucosal lesions. Cutaneous and mucosal lesions had a long-term evolution. Liver disease was discovered 2 to 6 years before LP in three cases and was diagnosed at the same time as LP in the three other cases. Liver biopsy performed in five patients showed chronic active hepatitis without cirrhosis in all five cases. Anti-HCV antibodies were detected in all cases by second-generation enzyme-linked immunosorbent assay and confirmed by second-generation recombinant immunoblot assay. Hepatitis C virus RNA was evidenced by means of polymerase chain reaction in the serum samples from the six patients, proving active viral replication. CONCLUSIONS: Lichen planus may be associated with HCV-related chronic active hepatitis. As interferon treatment may induce viral inactivation in some patients with HCV-related chronic liver disease, a search for HCV infection should be systematically performed in patients with chronic LP.

In situ hybridization analysis of human papillomavirus in orofacial lesions using a consensus biotinylated probe.

The effectiveness of the Viratype Omniprobe in situ human papillomavirus tissue hybridization kit (Digene Diagnostics) was evaluated for the detection of HPV DNA in common orofacial lesions. Seventy mucocutaneous lesions were hybridized with a biotinylated Omniprobe that was specific for HPV types 6, 11, 16, 18, 31, 33, 35, 42, 43, 44, 45, 51, 52, and 56. Eighteen (25.7%) of the specimens analyzed had intranuclear positive signals for HPV. Probing with HPV 6/11, 16/18, and 31/33/35 to delimit the HPV genotype yielded HPV DNA 6/11 in 16 (88.9%) of the Omniprobe-positive specimens. Only squamous papilloma and condyloma acuminatum were found to harbor HPV DNA. Sites most frequently infected were the labial and buccal mucosa (21.7%) and the floor of the mouth (17.4%). These results suggest that hybridization with the Omniprobe provides appropriate sensitivity and specificity for detecting HPV in some benign proliferations of the oral cavity. However, the detection of HPV in oral squamous cell carcinoma, lichen planus, and keratoacanthoma remains problematic until more sensitive and specific molecular techniques are used.

Superficial oral fungal infections.

Fungal infections in humans are provoked and exacerbated by defects in the cellular immune system. Hence, the emergence of novel clinical variants of oral candidoses and rare mycoses with the pandemic spread of human immunodeficiency virus infection is not surprising. The new clinical entities of oral candidoses that have been described in the past few years have had a significant impact on the classification of these diseases. Classification of oral candidoses is an issue addressed in some detail here. Angular cheilitis is a disease commonly associated with Candida infection. In the West, it is frequently seen in the elderly, but a report from Asia indicates that the disease may be prevalent in the young age groups due to factors such as anemia, despite the similarity of the infective agents. A novel cofactor implicated in infectious states has been the host blood group secretor status, and data from three studies suggest that the latter may play an intriguing role in the pathogenesis of oral candidosis. Finally, a new mouse model has been described as a substitute for the rat model in investigating the host-parasite interactions in oral candidosis, and its pros and cons are reviewed.

In situ DNA hybridization analysis of oral papillomas, leukoplakias, and carcinomas for human papillomavirus.

Twenty-one papillomas, 23 ordinary benign keratoses, 13 smokeless tobacco keratoses, 10 verrucous hyperplasias, 10 verrucous carcinomas, 17 squamous cell carcinomas, 3 epithelial dysplasias, and 6 lichen planus lesions were evaluated for human papillomavirus (HPV) types 6/11, 16/18, and 31/33/35, with biotinylated double-stranded DNA probes by in situ hybridization. Sixty-two percent (13/21) of oral squamous papillomas were positive for HPV DNA. HPV DNA types 6 and 11 demonstrated the strongest reactivity. Of the 13 cases, 10 also showed some reactivity with HPV-16/18 and -31/33/35. None of the cases of keratoses, epithelial dysplasia, squamous cell carcinoma, verrucous hyperplasia, verrucous carcinoma, or lichen planus were positive for HPV DNA. This study confirms the consistent and frequent finding of HPV DNA in oral squamous cell papillomas and the inconsistency of being able to identify HPV DNA in keratotic, premalignant, or cancerous lesions of the oral mucous membranes.

DNA-cytometric detection of euploid polyploidization in oral lichen ruber planus.

The DNA distribution was analyzed in 29 cases of oral lichen ruber planus that were negative for human papillomavirus and not suspected of being precancerous. Monolayer smears prepared from formalin-fixed, paraffin-embedded tissues were automatically Feulgen stained and used for rapid interactive DNA cytometry via a TV-based image analysis system combined with an automated microscope. Nuclei with DNA contents greater than 4c were found in 25 cases (86%). DNA contents greater than 8c were seen in five cases (17%), and small peaks at 8c were found in three cases. These increased DNA values in nonprecancerous lesions must be interpreted as euploid polyploidization and have to be taken into account if DNA measurements are performed for diagnostic purposes in lichen ruber planus lesions that are suspected of having malignant transformation.

Human papilloma virus in erosive oral lichen planus.

Several types of human papilloma viruses (HPV) have been associated with benign and malignant squamous cell tumours of mucosal epithelium. To identify HPV in erosive oral lichen planus (OLPe), considered as a premalignant lesion, tissues from 20 patients were examined by Southern blot hybridization with 32P-labeled HPV DNA probes. Type 11 was found in 6 of the lesions while HPV types 6, 16 and 18 were not detected in any of the tissues examined. Using a type-specific polymerase chain reaction (PCR) assay for HPV-6, 11, 16 and 18, HPV-11 was detected in 8 of the samples (all of those positive by Southern blot), and, in addition, HPV-6 was found in 5 samples and HPV-16 in 3 samples. Overall, by the more sensitive PCR assay, 65% of samples were positive for HPV DNA. The finding of HPV DNA in many of the samples using two different techniques indicates a high prevalence of HPV in the OLPe afflicted oral mucosa. However, the role of HPV in the pathogenesis of OLPe has yet to be determined.

Human papillomavirus in squamous cell carcinoma, leukoplakia, lichen planus, and clinically normal epithelium of the oral cavity.

Tissue specimens of carcinoma, leukoplakia, and clinically normal epithelium obtained at sites separate from the lesions were examined for the presence of human papillomavirus (HPV). Twenty-two paraffinized specimens of previously diagnosed oral lichen planus were also studied. The carcinoma and leukoplakia specimens were examined by Southern transfer hybridization and reverse blot hybridization; specimens HPV-positive by Southern hybridization were additionally examined by in situ hybridization and an immunoperoxidase technique. The lichen planus specimens were examined by in situ hybridization and immunoperoxidase techniques only. The HPV identification rates were in the range reported in previous studies, and the detection rates were similar for carcinoma, leukoplakia, histologically normal epithelium, and lichen planus. The clinical significance of HPV presence in carcinoma, leukoplakia, and lichen planus was not evaluable because of the short duration of follow-up.

Detection of human papillomavirus DNA in biopsies of human oral tissue.

We have employed molecular probes produced from DNA fragments of human papillomavirus, cloned into prokaryotic vectors, to detect virus nucleic acid sequences in extracts of human oral tissues. The study was conducted with duplicate coded snap-frozen tissue biopsies from which frozen sections had been taken to accurately assess the pathology of each particular sample. The results show that a large proportion of the oral biopsies contained DNA which hybridized to the viral DNA probes, even under conditions of high stringency. The presence of virus did not correlate with neoplasia in the tissues examined, but HPV like sequences were found in a high proportion (80%) of biopsies taken from areas of keratosis and lichen planus and also in 41 to 46% of normal and tumour tissues.

Yeast species and biotypes associated with oral leukoplakia and lichen planus.

Of 36 patients, 17 had oral leukoplakia, including homogeneous and nonhomogeneous types, and 19 had reticular lesions of oral lichen planus. A sample of yeast flora in each patient was taken from the pathologic lesion as well as from normal-appearing mucosa. The isolated yeasts were identified according to species level, and identification was extended beyond the species level for one species, Candida albicans, to reveal the biotype by means of the Odds and Abbott procedure comprising tests for acid and salt tolerance, proteinase production, resistance to 5-fluorocytosine and safranine, and assimilation of urea, sorbose, and citrate. Yeasts were present in the lesions of 82% of leukoplakia patients, compared to 37% of lichen planus patients, a frequency of yeasts corresponding to that in healthy adults. C. albicans was the dominating species in lesions of both diseases, constituting 82% of all yeasts in the leukoplakia lesions. In addition, the following species were identified: Candida tropicalis, Candida pintolopesii, Torulopsis glabrata, and Saccharomyces cerevisiae. Eighteen biotypes of C. albicans were encountered, the most frequently occurring biotypes being 355 and 177. Differences between C. albicans biotypes isolated from pathologic and normal mucosa were encountered in five of eleven leukoplakia patients and in one of three lichen planus patients. This indicates that the oral cavity comprises several ecologic niches for yeasts. As nonhomogeneous leukoplakias are more likely to develop into carcinoma than are homogeneous leukoplakias, it is interesting to note that the C. albicans biotypes isolated from nodular lesions (one type of nonhomogeneous leukoplakia)--biotypes 145, 175, and 575--rarely occur.(ABSTRACT TRUNCATED AT 250 WORDS)

Lichen planus: review and update on pathogenesis.

Lichen planus (LP) is a common oral disorder which may represent the manifestation of a mucosal reaction to a variety of aetiological factors. Of the many immunological changes described in LP several may be epiphenomena although a cell-mediated immune response to unidentified antigens or antigenic changes clearly is involved. Associations with drugs or systemic disorders are well-defined in some patients but may, in others, be aleatoric. Finally, the prognosis of oral LP not only differs from that of cutaneous LP but there is little doubt that in a few instances LP is a premalignant condition.

Candida in patients with oral lichen planus.

The presence of yeasts in oral lichen planus (OLP) lesions was studied in cultivations from 41 OLP patients and by histological examination in 39 of these cases. The histological features of OLP were also recorded. The cultivation results were compared with those of a randomly selected, age- and sex-matched control group without mucosal changes. The extent of growth was recorded as "sparse" (1-10 colonies), "model-rate" (11-40 colonies), or "heavy" (greater than 40 colonies). Yeasts were found to be present on cultures or histologic sections from a total of 19 OLP patients (46%). "Moderate-heavy" growth was obtained in 29% of the OLP cases but in only 7% of the control group. Candida albicans accounted for over 80% of the yeasts. The histological examination revealed only 3 cases of invasive fungal growth. Regarding the criteria of OLP, hyperortho- or hyperparakeratosis and a band-shaped subepithelial infiltration of lymphocytes were present in all specimens, basilar liquefaction degeneration in 87% and an eosinophilic zone in 77%. Local treatment with amphotericin B (Fungizone) in 18 OLP patients with positive findings resulted in subjective relief of symptoms in 89% of the patients. Clinical improvement was seen in 94%. The presence of Candida was significantly correlated to low secretion rate in unstimulated saliva.