C. Mark Nichols

Epstein-Barr Virus Replication in Oral Hairy Leukoplakia: Response, Persistence, and Resistance to Treatment with Valacyclovir

Nineteen cases of human immunodeficiency virus (HIV)-associated oral hairy leukoplakia (HLP) and Epstein-Barr virus (EBV) replication were treated with high-dose oral valacyclovir to inhibit productive EBV replication. The clinical, histopathological, and molecular viral responses to treatment were assessed in surgical biopsy specimens obtained before, during, and after treatment. In the majority of treated cases, HLP was resolved, and EBV replication was terminated. In many cases, the initial response to inhibition of replication was a persistent, nonproductive, EBV infection of the oral mucosa, characterized by limited expression of replicative EBV genes, especially BZLF1. In some cases, productive EBV replication recurred after discontinuation of treatment with valacyclovir. In a few treated cases, treatment failed, and productive EBV replication persisted, possibly because of the evolution of acyclovir-resistant EBV. In summary, safe treatment of HLP and of EBV replication, with valacyclovir, provides new insight into the mechanisms of EBV persistence in oral mucosa.

Persistent Productive Epstein-Barr Virus Replication in Normal Epithelial Cells In Vivo

Productive Epstein-Barr virus (EBV) replication characterizes hairy leukoplakia, an oral epithelial lesion typically occurring in individuals infected with human immunodeficiency virus (HIV). Serial tongue biopsy specimens were obtained from HIV-infected subjects before, during, and after valacyclovir treatment. EBV replication was detected by Southern hybridization to linear terminal EBV genome fragments, reverse-transcriptase polymerase chain reaction amplification of EBV replicative gene transcripts, immunohistochemical detection of EBV replicative protein, and in situ hybridization to EBV DNA. EBV replication was detected in both hairy leukoplakia and normal tongue tissues. Valacyclovir treatment completely abrogated EBV replication in vivo, resulting in resolution of hairy leukoplakia when it was present. EBV replication returned in normal tongue epithelial cells after valacyclovir treatment. These data suggest that normal oral epithelium supports persistent EBV infection in individuals infected with HIV and that productive EBV replication is necessary but not sufficient for the pathogenesis of oral hairy leukoplakia.

Herpesviridae-associated persistent mucocutaneous ulcers inacquired immunodeficiency syndrome

Persistent mucocutaneous ulcers in AIDS represent a variety of disease entities. The purpose of this study was to characterize clinicopathologic features of persistent oral ulcers associated with cytomegalovirus and herpes simplex virus in AIDS. Forty-seven persons infected with HIV with persistent ulcers (mean, 2.4 ulcers/person) were included in this study. A biopsy specimen from a representative ulcer was taken from each patient. Hematoxylin-eosin, periodic acid-Schiff, cytomegalovirus, and herpes simplex virus immunocytochemical stains were performed on tissue sections. The most common sites of involvement were the buccal/labial mucosa (27%), tongue (25%), and gingiva (18%). Mean ulcer size was 1.8 cm with a mean duration of 5.6 weeks. The ulcerogenic viral agents were cytomegalovirus alone in 53% of cases, cytomegalovirus and herpes simplex virus coinfection in 28% of cases, and herpes simplex virus alone in 19% of cases. Treatment response to ganciclovir with or without topical steroids resulted in lesion resolution in the cytomegalovirus and cytomegalovirus/herpes simplex virus groups; however, recurrence/resistance was relatively high (23%). Herpes simplex virus/cytomegalovirus ulcers responded to oral acyclovir in combination with systemic ganciclovir. Increasing the oral acyclovir dosage resulted in resolution of herpes simplex virus-only ulcers in all but one case. Cytomegalovirus and herpes simplex virus are associated with persistent mucocutaneous ulcers in AIDS. These lesions responded to systemic antiviral therapy but are difficult to differentiate from other ulcerogenic diseases such as aphthous major, necrotizing stomatitis, and ulcerations not otherwise specified without biopsy and histopathologic examination.

Epstein-Barr Virus Infection of Langerhans Cell Precursors as a Mechanism of Oral Epithelial Entry, Persistence, and Reactivation

ABSTRACT Epstein-Barr virus (EBV) is a ubiquitous human herpesvirus associated with many malignant and nonmalignant human diseases. Life-long latent EBV persistence occurs in blood-borne B lymphocytes, while EBV intermittently productively replicates in mucosal epithelia. Although several models have previously been proposed, the mechanism of EBV transition between these two reservoirs of infection has not been determined. In this study, we present the first evidence demonstrating that EBV latently infects a unique subset of blood-borne mononuclear cells that are direct precursors to Langerhans cells and that EBV both latently and productively infects oral epithelium-resident cells that are likely Langerhans cells. These data form the basis of a proposed new model of EBV transition from blood to oral epithelium in which EBV-infected Langerhans cell precursors serve to transport EBV to the oral epithelium as they migrate and differentiate into oral Langerhans cells. This new model contributes fresh insight into the natural history of EBV infection and the pathogenesis of EBV-associated epithelial disease.

Kaposi's sarcoma-associated herpesvirus-like DNA sequences (KSHV/HHV-8) in oral AIDS-Kaposi's sarcoma : A PCR and clinicopathologic study

Recently, a new human herpesvirus (KSHV/HHV-8) has been identified in classic, transplant, endemic, and AIDS Kaposis sarcoma that may be involved in the pathogenesis of Kaposis sarcoma. The purpose of this study was to evaluate oral AIDS-Kaposis sarcoma for detection of KSHV/HHV-8 DNA. DNA extracted from 54 oral AIDS-Kaposis sarcoma lesions (47 initial, 7 postvinblastine treated), 5 non-Kaposis sarcoma HIV-positive lesions, and 3 non-Kaposis sarcoma HIV-negative lesions was evaluated by polymerase chain reaction (KS330(233bp)amplicon) for KSHV/HHV-8. The AIDS-Kaposis sarcoma study population consisted of 52 patients (51:1, men:woman; 92% men having sex with men, 8% heterosexual; mean age, 38 years; mean, CD4 59/mm3) Opportunistic infections occurred in 88% (candidiasis, 65%; Pneumocystis carinii pneumonia, 31%; nonoral Kaposis sarcoma, 25%; mycobacterium avium-intracellulare (MAI), 16%; cytomegalovirus, 14%; herpes simplex virus, 14%). Sexually transmitted diseases occurred in 73% (gonorrhea, 37%; syphilis, 23%; condyloma, 22%; HSV, 16%). Most frequent lesion sites were palate (74%) and gingiva (17%). Most common lesion types were purple nodular (48%) and macular (42%). Histopathologic subtypes were nodular (71%), plaque (27%), and patch (2%). Polymerase chain reaction analysis detected KSHV/HHV-8 DNA in 53 of 54 AIDS-Kaposis sarcoma lesions (47 of 47 initial, 6 of 7 postvinblastine treatment). KSHV/HHV-8 DNA was not detected in non-Kaposis sarcoma lesions in HIV-positive or HIV-negative persons. KSHV/HHV-8 DNA sequence is present in a high proportion of oral AIDS-Kaposis sarcoma lesions. Whether KSHV/HHV-8 is an etiologic agent or a cofactor in the development of this vascular neoplasm is uncertain and remains to be proven. Polymerase chain reaction analysis for KSHV/HHV-8 DNA sequence detection may be helpful in identifying Kaposis sarcoma in early vascular proliferations, when the characteristic histopathologic features are not present.

Intraoral squamous cell carcinoma in human immunodeficiency virus infection. A clinicopathologic study.

The purpose of this study was to characterize the clinical and histological features of intraoral squamous cell carcinoma in men who were seropositive for the human immunodeficiency virus and to evaluate viral cofactors (human papillomavirus, herpes simplex virus, Epstein-Barr virus), proliferative index (proliferating cell nuclear antigen), a factor associated with invasion (cathepsin D), and mutated tumor suppressor gene and proto-oncogene products (mutated p53, c-erbB-2). Four men who were seropositive for the human immunodeficiency virus and had acquired immunodeficiency syndrome presented with painful oral lesions of variable duration. Oral cancer risk factors included heavy tobacco use (four of four), heavy alcohol use (three of four), and previous radiotherapy (one of four). The lesions consisted of ulcers (two of four), a fungating mass (one of four), and papillary erythroplakia (one of four). Incisional biopsy specimens were obtained. High-stringency in situ hybridization was performed with DNA probes to the human papillomavirus (types 6/11; 16/18; 31/33/35) and Epstein-Barr virus: Immunocytochemical studies for the herpes simplex virus, proliferating cell nuclear antigen, cathepsin D, mutated p53, and c-erbB-2 were performed. Two lesions were moderately differentiated squamous cell carcinoma, one lesion was a basaloid squamous cell carcinoma, and one was carcinoma in situ. Stage of disease at diagnosis was II (one of four), III (two of four), and IV (one of four). Three cases were positive for the human papillomavirus, one case was positive for Epstein-Barr virus, and three cases were positive for the herpes simplex virus. C-erbB-2 was focally positive in one case, and mutated p53 was positive in a separate case.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of Epstein-Barr Virus Latent Genes in Oral Epithelium: Determinants of the Pathogenesis of Oral Hairy Leukoplakia

This retrospective study examined expression of Epstein-Barr virus (EBV) latent genes in oral epithelium from human immunodeficiency virus-seropositive subjects, to identify genes associated with the pathogenesis of oral hairy leukoplakia (HLP). Transcription of EBV latent genes was detected in tissues with productive EBV replication and, also, in normal oral epithelial tissues without EBV replication. Expression of the EBV EBNA-2 open-reading frame in oral epithelium was identified as an important cofactor associated with the pathogenesis of HLP. In vitro experiments suggested that a recombinant variant of the EBNA-2 gene may play a role in the pathogenesis of HLP, through modulation of EBNA-2 protein function.

Persistence and Transition of Epstein-Barr Virus Genotypes in the Pathogenesis of Oral Hairy Leukoplakia

This prospective study examined the persistence and transition of Epstein-Barr virus (EBV) in human immunodeficiency virus (HIV)-seropositive subjects with and without oral hairy leukoplakia, a replicative EBV-associated epithelial disease. The intrahost molecular epidemiology of EBV infection was characterized in subjects treated with valacyclovir to suppress EBV replication. Tongue epithelial tissues of HIV-seropositive subjects were found to support not only EBV replication but also persistent, nonproductive EBV infection. EBV appeared to enter the tongue from the blood reservoir of infection and, possibly, from exogenous sources as well. EBV transition from the blood to the tongue appeared to occur even during valacyclovir-mediated suppression of EBV replication, suggesting EBV entry into tongue epithelial tissue as a cell-associated latent infection. In conclusion, these results describe the persistence and transition of EBV as a dynamic interaction between the blood and epithelial reservoirs of EBV infection and suggest a role for entry, persistence, and reactivation of oral epithelial EBV in the pathogenesis of oral hairy leukoplakia.

Effect of Epstein-Barr Virus Replication on Langerhans Cells in Pathogenesis of Oral Hairy Leukoplakia

Epstein-Barr virus (EBV) replicates productively in oral hairy leukoplakia (HLP). One characteristic of human immunodeficiency virus (HIV)-associated HLP is a decreased oral epithelial Langerhans cell count. This prospective study tested the hypothesis that oral epithelial EBV replication decreases oral Langerhans cell counts. EBV replication in HLP was highly correlated with decreased oral Langerhans cell counts. Inhibition of EBV replication restored oral Langerhans cell counts to normal control levels, and the return of EBV replication after treatment resulted in a recurrent decline in oral Langerhans cell counts. Decreased oral Langerhans cell counts occurred independently of HIV infection, as demonstrated in HLP of otherwise healthy HIV-seronegative individuals. These results support the tested hypothesis and suggest that EBV manipulates and evades the mucosal immune response in oral epithelial infection. This novel EBV strategy for eliminating oral Langerhans cells may facilitate the persistence of oral epithelial EBV and may contribute to the pathogenesis of HLP.

Intraoral presentation of anaplastic large-cell Ki-1 lymphoma in association with HIV infection☆

Persons infected with human immunodeficiency virus have an increased risk for development of high-grade, non-Hodgkins lymphomas. Anaplastic large-cell Ki-1 lymphoma is a recently described lymphoid neoplasm characterized by cellular pleomorphism, a sinusoidal growth pattern, and Ki-1 epitope reactivity. This type of lymphoma is often mistaken for metastatic carcinoma, melanoma, or malignant histiocytosis. Although persons with acquired immunodeficiency syndrome frequently have non-Hodgkins lymphoma at extranodal sites, the oral cavity and mandible, in particular, are unusual locations. We report two cases of anaplastic large-cell Ki-1 lymphoma that occurred in persons with the human immunodeficiency virus and with initial presentation as soft tissue masses of the posterior mandible. Immunocytochemical studies were positive for Ki-1 (CD30) in both cases. In situ hybridization for Epstein-Barr virus-deoxyribonucleic acid was positive with tumor cells in both cases. Flow cytometry on paraffin, formalin-fixed tissue revealed tetraploidy and high proliferative fractions that are characteristic of high-grade lymphomas. Intraoral presentation of rapidly enlarging, soft tissue masses may represent a high-grade non-Hodgkins lymphoma in persons with the human immunodeficiency virus. Although rare, anaplastic large-cell Ki-1 lymphoma should be considered and requires immunocytochemical study to eliminate the possibility of other malignant conditions associated with the acquired immunodeficiency syndrome.