Epstein-Barr virus infection and expression in oral lesions

Air-Liquid Interface Method To Study Epstein-Barr Virus Pathogenesis in Nasopharyngeal Epithelial Cells

Epstein-Barr virus (EBV) is a ubiquitous gammaherpesvirus that establishes a latent reservoir in peripheral B-lymphocytes with sporadic reactivation. EBV also infects epithelial cells, predominantly resulting in a lytic infection, which may contribute to EBV transmission from saliva. In the nasopharynx, EBV infection can lead to the clonal expansion of a latently infected cell and the development of nasopharyngeal carcinoma (NPC). The mechanisms governing EBV pathogenesis in nasopharyngeal epithelium are largely unknown. An advanced understanding would depend on a physiologically relevant culture model of polarized airway epithelium. The recent application of the organotypic raft culture in keratinocytes has demonstrated great promise for the use of polarized cultures in the study of EBV permissive replication. In this study, the adaptation of an air-liquid interface (ALI) culture method using transwell membranes was explored in an EBV-infected NPC cell line. In the EBV-infected NPC HK1 cell line, ALI culture resulted in the completion of EBV reactivation, with global induction of the lytic cascade, replication of EBV genomes, and production of infectious progeny virus. We propose that the ALI culture method can be widely adopted as a physiologically relevant model to study EBV pathogenesis in polarized nasal epithelial cells.

IMPORTANCE

Lifting adherent cells to the air-liquid interface (ALI) is a method conventionally used to culture airway epithelial cells into polarized apical and basolateral surfaces. Reactivation of Epstein-Barr virus (EBV) from monolayer epithelial cultures is sometimes abortive, which may be attributed to the lack of authentic reactivation triggers that occur in stratified epithelium in vivo In the present work, the ALI culture method was applied to study EBV reactivation in nasopharyngeal epithelial cells. The ALI culture of an EBV-infected cell line yielded high titers and can be dissected by a variety of molecular virology assays that measure induction of the EBV lytic cascade and EBV genome replication and assembly. EBV infection of polarized cultures of primary epithelial cells can be challenging and can have variable efficiencies. However, the use of the ALI method with established EBV-infected cell lines offers a readily available and reproducible approach for the study of EBV permissive replication in polarized epithelia.

Hairy leukoplakia; lessons learned: 30-plus years

Well into the fourth decade of the HIV/AIDS pandemic, we can look back on the early years, the initial discoveries, and the broad sweep of the progress of our understanding of the nature, causes, and significance of the oral lesions seen in those infected with the virus. Prominent among these is oral hairy leukoplakia (HL), a previously unknown lesion of the mouth associated with Epstein-Barr virus (EBV) and initially seen only in people with AIDS, in the then-recognized risk groups, or those shown to be HIV positive. Subsequently, it became clear that the distribution of HL extends well beyond the HIV spectrum. In this brief review, we consider the clinical and histological features of HL, discuss how it was discovered, explore its cause, diagnosis, relationship with AIDS, pathogenesis, significance in EBV biology, options for management, and how it changes with HIV/AIDS therapy.

Oral ulceration associated with concurrent herpes simplex virus, cytomegalovirus, and Epstein-Barr virus infection in an immunocompromised patient

In immunocompromised patients, oral ulcerations are common and have a wide spectrum of causes, including herpesvirus infection. We report on a case in which an oral ulcer was simultaneously infected by herpes simplex (HSV), cytomegalovirus (CMV), and Epstein-Barr virus (EBV) in a kidney-pancreas transplant recipient. A 46-year-old woman presented with a clinically nonspecific dorsal tongue ulcer of 3 months duration. Histopathologic evaluation indicated keratinocytes exhibiting herpetic viral cytopathic effect. Nuclear and cytologic alterations suggestive of CMV infection were found in endothelial cells subjacent to the ulcer. Immunohistochemistry testing for HSV and CMV was positive in these cells. Large atypical mononuclear cells were also evident in the ulcer bed's inflammatory infiltrate, which had intense nuclear positivity for Epstein-Barr encoding region in situ hybridization. We believe this is the first well-documented report of the definitive concomitant presence of HSV, CMV, and EBV in an immunocompromised patient. Although the pathogenesis of coinfected ulcers remains unknown, a synergistic effect is possible.

Epstein-Barr virus (EBV) infection in Chinese children: a retrospective study of age-specific prevalence

Background

Epstein-Barr Virus (EBV) is a globally prevalent herpesvirus associated with infectious mononucleosis and many malignancies. The survey on EBV prevalence appears to be important to study EBV-related diseases and determine when to administer prophylactic vaccine. The purpose of this retrospective study was to collect baseline information about the prevalence of EBV infection in Chinese children.

Methodology/Principal Finding

We collected 1778 serum samples from healthy children aged 0 to 10, who were enrolled in conventional health and nutrition examinations without any EBV-related symptom in 2012 and 2013 in North China (n = 973) and South China (n = 805). We detected four EBV-specific antibodies, i.e., anti-VCA-IgG and IgM, anti-EBNA-IgG and anti-EA-IgG, by ELISA, representing all of the phases of EBV infection. The overall EBV seroprevalence in samples from North and South China were 80.78% and 79.38% respectively. The EBV seropositivity rates dropped slightly at age 2, and then increased gradually with age. The seroprevalence became stabilized at over 90% after age 8. In this study, the seroprevalence trends between North and South China showed no difference (P>0.05), and the trends of average antibody concentrations were similar as well (P>0.05).

Conclusions/Significance

EBV seroprevalence became more than 50% before age 3 in Chinese children, and exceed 90% after age 8. This study can be helpful to study the relationship between EBV and EBV-associated diseases, and supportive to EBV vaccine development and implementation.

Oral ulcers in HIV-positive Peruvian patients: an immunohistochemical and in situ hybridization study

BACKGROUND

This study describes the histopathological, immunohistochemical (IHC) and in situ hybridization (ISH) data of 25 cases of oral ulcers in HIV-positive patients, with clinical and microscopical features similar to ulcers not otherwise specified (NOS)/necrotizing ulcerative stomatitis (NUS).

METHODS

Sex, age and clinical history were obtained from the clinical records. Histological analysis for H&E, Gomori-Grocott and Ziehl-Neelsen stains, IHC analysis to detect infectious agents and to characterize inflammatory cellular infiltrate, and ISH for cytomegalovirus (CMV) and EBER1/2 were performed.

RESULTS

Twenty-one patients were men and four were women (mean age of 34.6 years). The tongue was preferentially affected. Microscopically, the lesions showed extensive necrosis, leukocytoclasia, vasculitis with luminal fibrin clots and an intense inflammatory cellular infiltrate predominated by CD68(+) atypical large cells, normal-sized and crescent-shaped nuclei macrophages, interspersed by CD8(+) T lymphocytes. Mast cells were also observed in all samples studied. CD4(+) T lymphocytes, CD20(+) B lymphocytes and VS38c(+) plasma cells were practically absent. CMV and EBER1/2 were identified in scarce cells of 3 and 16 of 25 cases respectively.

CONCLUSION

These results show that CD68(+) macrophages, followed by CD8(+) T lymphocytes, were the predominant inflammatory cells, indicating they are relevant to the pathogenesis of the ulcers, possibly reflecting an abnormal immune response in the oral mucosa. The clinicopathological and immunoprofile features of the present cases are similar to NOS ulcers/NUS in HIV-positive patients.

Targeted therapy of oral hairy leukoplakia with gentian violet

Oral hairy leukoplakia (OHL) is a common oral manifestation of HIV infection. Clinically, these lesions appear as white plaques on the edges of the tongue. Pathophysiologically, these lesions occur because of infection of oral epithelium with Epstein-Barr virus (EBV). No universally effective therapy exists for OHL. We have previously shown that EBV infection and EBV viral products induce the generation of reactive oxygen. We have also demonstrated that the Food and Drug Administration-approved over-the-counter medication gentian violet is a potent inhibitor of reactive oxygen species. We thus chose to treat a patient with biopsy-proven OHL with topical gentian violet. Gentian violet solution was applied topically to the tongue of a patient with OHL. Complete clinical resolution was noted after three treatments. Treatment with topical gentian violet resulted in resolution of the lesions. Further studies with larger numbers of patients are required. The application of gentian violet can be used as a method to OHL treatment. Gentian violet is an inexpensive and safe therapy and, given that it inhibits reactive oxygen, this old therapy is now a targeted novel therapy.

Detection of the Epstein-Barr virus (EBV) by in situ hybridization as definitive diagnosis of hairy leukoplakia

Histopathological findings in cases of hairy leukoplakia (HL) are not exclusive to this lesion. A total of 36 tissue samples from patients previously diagnosed with HL based solely on morphological aspects were used in this study. Our purpose was to confirm the presence of Epstein-Barr virus (EBV) in these tissue samples by in situ hybridization (ISH), and to compare the detection of EBV with specific histopathological findings observed in each case. Among the 36 specimens, 80.55% were EBV positive, confirming the previous clinical and histhophatological diagnosis. None of the histopathological findings analyzed correlated with the presence or absence of EBV. This shows that a definitive diagnosis of HL cannot be established based on histopathological findings alone. Because there are many important implications on the establishment of definitive diagnosis of HL, the detection of EBV by ISH is obligatory.

Detection of Epstein-Barr virus (EBV) in the oral mucosa of renal transplant patients

The purpose of this study was to determine the prevalence of Epstein-Barr virus (EBV)-DNA in the oral mucosa of renal transplant patients and observe the efficacy of mouth rinses with phosphate-buffered saline (PBS) to eliminate EBV present in the saliva. Lingual, gingival, and buccal cytobrushings were obtained from normal oral mucosa of 10 renal transplant patients and 10 normal subjects, and were examined through polymerase chain reaction (PCR), before and after rinses with PBS. EBV-DNA was detected in 86.6% of renal transplant recipients and in 46.6% of healthy subjects. No significant difference was observed between oral scrapes obtained before and after rinses with PBS with regard to detection of EBV-DNA. Our results suggest that the use of PCR to detect the presence of EBV-DNA in oral mucosa in the absence of specific lesions gives rise to the problem of identifying the viral replication sites. In addition, PBS was not effective at minimizing contamination by saliva.

Virologic Diagnosis, Viral Monitoring, and Treatment of Epstein-Barr Virus Infectious Mononucleosis

Epstein-Barr virus (EBV) is the cause of infectious mononucleosis and is associated with severe infections in immunocompromised patients. EBV is also causally linked with several human malignancies. The heterophile antibody test and EBV-specific antibody tests remain the principal means of diagnosis of initial infection in otherwise healthy patients. Enzyme-linked immunosorbent assays have replaced the traditional immunofluorescence assays for EBV-specific antibodies. Several newer molecular diagnostic tests have become available that facilitate accurate monitoring of infection. The role of these tests for patients with uncomplicated infectious mononucleosis is limited, although these tests are being increasingly used to monitor the state and level of EBV replication for severe infections and among immunocompromised patients. Antiviral therapy has a limited, short-term effect on oropharyngeal shedding but has proven ineffective for the clinical manifestations of infectious mononucleosis. Patients with selected complications frequently benefit from short-term corticosteroid therapy.

Oral Kaposi's sarcoma: a clinicopathologic study from South Africa

OBJECTIVES

In this retrospective study, we defined the clinicopathologic characteristics of oral Kaposi's sarcoma (KS) and determined the presence of human herpesvirus 8 in the oral lesions in a group of South African patients. These results were compared with similar data from patients in developed countries.

STUDY DESIGN

Eighty-one cases of oral KS were retrieved from the departmental archives. Fourteen patients with oral pyogenic granuloma served as control subjects. DNA was extracted by using a modified phenol chloroform extraction method and amplified by using polymerase chain reaction. If beta-globin DNA sequences could not be demonstrated, the patient was excluded from the study.

RESULTS

Of the 81 patients included in the study, 68 (84%) had been diagnosed since 1997. Oral KS was often the first presenting sign of human immunodeficiency virus infection. Some of the lesions exceeded 4 cm in diameter. The most commonly affected site was the palate (37 patients), followed by the tongue and gingiva. Multiple oral sites were frequently involved. The mean age of the patients was 34.7 years (range, 2-58 years). The male-to-female ratio was 1.31 to 1. Most of the patients (94%) were black. Human herpesvirus 8 DNA sequences were detected in 44 of the 45 cases of oral KS in which the DNA was analyzed, and in 1 case of pyogenic granuloma.

CONCLUSIONS

The only significant clinicopathologic differences in findings between our study and previous studies in developed countries were (1) the male-to-female ratio, (2) the preponderance of black patients, and (3) the more frequent involvement of the tongue. There are no studies reporting the clinicopathologic characteristics of oral KS in populations of developing countries.

Modulation of histone acetyltransferase activity through interaction of epstein-barr nuclear antigen 3C with prothymosin alpha

The Epstein-Barr virus (EBV) nuclear antigen 3C (EBNA3C) is essential for EBV-dependent immortalization of human primary B lymphocytes. Genetic analysis indicated that amino acids 365 to 992 are important for EBV-mediated immortalization of B lymphocytes. We demonstrate that this region of EBNA3C critical for immortalization interacts with prothymosin alpha (ProTalpha), a cellular protein previously identified to be important for cell division and proliferation. This interaction maps to a region downstream of amino acid 365 known to be involved in transcription regulation and critical for EBV-mediated transformation of primary B lymphocytes. Additionally, we show that EBNA3C also interacts with p300, a cellular acetyltransferase. This interaction suggests a possible role in regulation of histone acetylation and chromatin remodeling. An increase in histone acetylation was observed in EBV-transformed lymphoblastoid cell lines, which is consistent with increased cellular gene expression. These cells express the entire repertoire of latent nuclear antigens, including EBNA3C. Expression of EBNA3C in cells with increased acetyltransferase activity mediated by the EBV transactivator EBNA2 results in down-modulation of this activity in a dose-responsive manner. The interactions of EBNA3C with ProTalpha and p300 provide new evidence implicating this essential EBV protein EBNA3C in modulating the acetylation of cellular factors, including histones. Hence, EBNA3C plays a critical role in balancing cellular transcriptional events by linking the biological property of mediating inhibition of EBNA2 transcription activation and the observed histone acetyltransferase activity, thereby orchestrating immortalization of EBV-infected cells.

Necrotizing ulcerative stomatitis in human immunodeficiency virus-seropositive individuals: a review of the histopathologic, immunohistochemical, and virologic characteristics of 18 cases

OBJECTIVE

The purpose of this retrospective study was to delineate the histopathologic, immunohistochemical, and virologic characteristics of 18 cases of necrotizing ulcerative stomatitis.

STUDY DESIGN

Eighteen examples or oral ulcerations in human immunodeficiency virus-seropositive individuals were identified that displayed unique histopathologic features. Immunohistochemic staining for CD1a, CD3, CD23, CD68, HLA-DR, p24, cytomegalovirus, HSV-1, and HSV-2 was performed, along with in situ hybridization for Epstein-Barr virus RNA and special staining for bacteria and fungi.

RESULTS

The lesions demonstrated ulceration, extensive necrosis, leukocytoclasia, histiocytic vasculitis with luminal fibrin clots, and a prominent infiltrate of large atypical cells with amphophilic cytoplasm, vesicular nuclei, and prominent nucleoli, interspersed with crescentic histiocytes, a histologic picture resembling extranodal Kikuchi's disease. Immunohistochemical findings suggested that the large atypical cells were histiocytes. Fifty-six percent (10/18) of the cases were immunoreactive for human immunodeficiency virus p24 within focal histiocytes, whereas Epstein-Barr virus RNA was identified in 1 (6%) of 17 cases.

CONCLUSIONS

Necrotizing ulcerative stomatitis is an inflammatory disease characterized by specific, reproducible microscopic features. We postulate that the histopathologic resemblance of necrotizing ulcerative stomatitis to extranodal Kikuchi's disease reflects a similar immune response to differing pathogens.

Oral infections and other manifestations of HIV disease

Oral lesions are important in the clinical spectrum of HIV/AIDS, arousing suspicion of acute seroconversion illness (aphthous ulceration and candidiasis), suggesting HIV infection in the undiagnosed individual (candidiasis, hairy leukoplakia, Kaposi's sarcoma, necrotizing ulcerative gingivitis), indicating clinical disease progression and predicting development of AIDS (candidiasis, hairy leukoplakia), and marking immune suppression in HIV-infected individuals (candidiasis, hairy leukoplakia, necrotizing periodontal disease, Kaposi's sarcoma, long-standing herpes infection, major aphthous ulcers). In addition, oral lesions are included in staging systems for HIV disease progression and as entry criteria or endpoints in clinical trials of antiretroviral drugs. Recognition and management of these oral conditions is important for the health and quality of life of the individual with HIV/AIDS. In keeping with this, the U.S. Department of Health Services Clinical Practice Guideline for Evaluation and Management of Early HIV Infection includes recommendations that an oral examination, emphasizing oral mucosal surfaces, be conducted by the primary care provider at each visit, a dental examination by a dentist should be done at least two times a year, and patients should be informed of the importance of oral care and educated about common HIV-related oral lesions and associated symptoms.

Clinical management of selected oral fungal and viral infections during HIV-disease

The purpose of this review is to describe current possibilities of management of selected fungal and viral oral opportunistic infections including oral candidiasis, herpes simplex type 1 and 2-related lesions (HSV1,2), oral hairy leukoplakia (OHL) and oral lesions associated with human papilloma viruses (HPV). Less common diseases such as cytomegalovirus infection or human herpes virus type 8 associated with Kaposi's sarcoma and others are not considered. In a number of instances lifelong therapy or prophylaxis has to be instituted. Antiretroviral combination therapy, also called highly active antiretroviral therapy (HAART), has considerably changed the frequency of oral lesions caused by opportunistic agents. A short description of the antiretroviral agents available including respective side-effects is presented.

Oral ulcers in AIDS patients frequently associated with cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections

Oral ulcers are common in AIDS patients, with a wide spectrum of underlying causes, including different viruses. In the present study, the presence of cytomegalovirus (CMV), Epstein-Barr virus (EBV) and human herpesvirus-8 (HHV-8) DNA was analysed in 21 biopsies from oral ulcers of 17 male homosexual AIDS patients. The methods used were in situ hybridization (ISH) and the polymerase chain reaction (PCR) with subsequent non-radioactive Southern blot hybridization to confirm the specificity of PCR products. With ISH, 4 biopsies were CMV DNA-positive and 11 contained EBV-DNA. Using PCR, an additional 4 CMV- and 7 EBV-positive samples were detected, and HHV-8 DNA was present in three oral ulcers. Six of the patients (35%) had oral ulcers co-infected by two or three viruses. The overall figures for patients with the detectable EBV-, CMV-, and HHV-8 DNA were 82% (14/17), 35% (6/17) and 18% (3/17), respectively. This is the first study to show the frequent presence of EBV-DNA in oral ulcers of AIDS patients. Because ISH-positivity signifies active virus replication, these results implicate an etiological role of EBV in AIDS-associated oral ulcers. The causal role of HHV-8 has to be considered as well, because this virus was detected in three such ulcers, which were not associated with Kaposi's sarcoma. To conclude, three common members of the herpesvirus family (CMV, EBV, HHV-8) were detected in all but three ulcers in AIDS patients, warranting the inclusion of these viral analyses in the diagnosis of ulcerative lesions of the oral mucosa in all immunosuppressed individuals.

Epstein-Barr virus and lymphoproliferative disease

The Epstein-Barr virus is a ubiquitous human herpesvirus that is associated with an increasing number of human malignancies. Among these are Epstein-Barr virus-associated lymphoproliferative diseases in immunocompromised patients, a spectrum of mainly B-cell diseases that range from polyclonal lymphoproliferative diseases, which resolve when immunosuppression is halted, to highly malignant lymphomas. Progress has identified Epstein-Barr virus gene products involved in B-cell transformation, variation in Epstein-Barr virus transforming genes, distinct target cell populations with differing regulation of Epstein-Barr virus expression, and selective recruitment of other supportive cell types as factors in the heterogeneity of lymphoproliferative diseases. New therapeutic approaches to treat lymphoproliferative diseases are also being developed. Finally, xenotransplantation poses new risks for the introduction of Epstein-Barr virus-like viruses and more aggressive lymphoproliferative diseases in heavily immunosuppressed patients.

Detection of Epstein-Barr virus in oral scrapes in HIV infection, in hairy leukoplakia, and in healthy non-HIV-infected people

Epstein Barr virus (EBV) has been implicated in the pathogenesis of oral hairy leukoplakia (OHL). EBV is normally detected by lesional biopsy. The objectives of this study were to examine oral scrapes containing squamous epithelial cells (squames) from HIV-infected people with and without clinical lesions of OHL, and from healthy non-HIV-infected controls, for EBV-DNA by the polymerase chain reaction (PCR). EBV-DNA was detected in 65% of HIV-infected people and 20% of healthy HIV-negative controls but in HIV-infected individuals it was found as frequently in those without OHL as in those with. Moreover, EBV-DNA was not detected in all HIV-infected individuals, nor in all OHL. The results suggest that the presence or absence of detectable EBV-DNA in oral scrapes, though a guide, cannot be regarded as absolutely reliable in the diagnosis or exclusion of OHL.