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Fulltext Clonal proliferations of cells infected with Epstein-Barr virus in preinvasive lesions related to nasopharyngeal carcinoma

Pathmanathan R, Prasad U, Sadler R, Flynn K, Raab-Traub N

N Engl J Med, 1995 Sep 14;333(11):693-8.
PMID: 7637746 DOI: 10.1056/NEJM199509143331103

BACKGROUND: The Epstein-Barr virus (EBV) is consistently detected in patients with nasopharyngeal carcinoma. To determine whether EBV infection is an early, initiating event in the development of this malignant tumor, we screened nasopharyngeal-biopsy samples, most of which were archival, for preinvasive lesions, including dysplasia and carcinoma in situ. Preinvasive lesions were found in 11 samples, which were tested for the presence of EBV.
METHODS: EBV infection was detected with in situ hybridization for EBV-encoded RNAs (EBERs) and by immunohistochemical staining for latent membrane protein 1 (LMP-1). The larger samples were also tested for the EBV genome with the use of Southern blotting. The expression of specific EBV RNAs was determined by the amplification of complementary DNA with the polymerase chain reaction.
RESULTS: Evidence of EBV infection was detected in all 11 tissue samples with dysplasia or carcinoma in situ. EBERs were identified in all eight samples tested, and LMP-1 was detected in all six of the tested samples. Six of the seven samples tested for the EBV termini contained clonal EBV DNA: Transcription of the latent EBV gene products, EBV nuclear antigen 1, LMP-1, LMP-2A, and the BamHI-A fragment, was detected in most of the samples. Viral proteins characteristic of lytic lesions were not detected.
CONCLUSIONS: Preinvasive lesions of the nasopharynx are infected with EBV. The EBV DNA is clonal, indicating that the lesions represent a focal cellular growth that arose from a single EBV-infected cell and that EBV infection is an early, possibly initiating event in the development of nasopharyngeal carcinoma. Preinvasive lesions contain EBV RNAs that are characteristic of latent infection but not the viral proteins that are characteristic of lytic infection. The detection of the EBV-transforming gene, LMP-1, in all the neoplastic cells suggests that its expression is essential for preinvasive epithelial proliferations associated with nasopharyngeal carcinoma.

Matched MeSH terms: Herpesviridae Infections/complications; Herpesviridae Infections/diagnosis*
Fulltext Multi-assay investigation of viral etiology in pediatric central nervous system infections

Altay-Kocak A, Bozdayi G, Michel J, Polat M, Kanik-Yuksek S, Tezer H, et al.

J Infect Dev Ctries, 2020 06 30;14(6):572-579.
PMID: 32683347 DOI: 10.3855/jidc.12327

INTRODUCTION: In an attempt to identify a wide spectrum of viral infections, cerebrospinal fluid (CSF) specimens were collected from pediatric cases with the preliminary diagnosis of viral encephalitis/meningoencephalitis in two reference hospitals, from October 2011 to December 2015.
METHODOLOGY: A combination of nucleic acid-based assays, including in house generic polymerase chain reaction (PCR) assays for enteroviruses, flaviviruses and phleboviruses, a commercial real-time PCR assay for herpesviruses and a commercial real time multiplex PCR, enabling detection of frequently-observed viral, bacterial and fungal agents were employed for screening.
RESULTS: The microbial agent could be characterized in 10 (10%) of the 100 specimens. Viral etiology could be demonstrated in 7 (70%) specimens, which comprises Human Herpesvirus 6 (4/7), Herpes Simplex virus type1 (2/7) and Enteroviruses (1/7). In 3 specimens (30%), Streptococcus pneumoniae, Listeria monocytogenes and Staphylococcus aureus were detected via the multiplex PCR, which were also isolated in bacteriological media. All specimens with detectable viral nucleic acids, as well as unreactive specimens via nucleic acid testing remained negative in bacteriological cultures.
CONCLUSIONS: Herpes and enteroviruses were identified as the primary causative agents of central nervous system infections in children. Enterovirus testing must be included in the diagnostic work-up of relevant cases.

Matched MeSH terms: Herpesviridae Infections/cerebrospinal fluid; Herpesviridae Infections/virology
Development of immunity to Epstein-Barr virus in Malaysian children

Yadav MS, Malliga N, Ablashi DV

Microbiologica, 1987 Jan;10(1):29-35.
PMID: 3033449

The pattern of seroconversion to Epstein-Barr virus (EBV) was determined in 98 Malaysian children aged 2 weeks to 12 years. Maternal IgG antibodies to EBV viral capsid antigen, ranging between 1:10 to 1:160 titer, were found in 70.6 percent of infants less than three months old, and dropped to 26 percent by seven to nine months. Primary infection, as denoted by emergence of EBV-IgM antibody, occurred at 4 to 6 months, and by eight years all children were seropositive. Maternal antibody titers to EBV nuclear antigen were detected in 52.9 percent of infants less than 3 months old, declined to undetectable levels by 4 to 12 months, and then increased to 40 percent by the age of 12 years. The IgA antibody to viral capsid antigen was absent in all but one infant aged one year; the child also had IgG anti-early antigen, The IgG antibody to EBV early antigen were present in 17.7 percent of the infants aged 3 months or less. This seroconversion to EBV in early life explains the absence of infectious mononucleosis in the Malaysian population. The data suggest that a subunit vaccine to protect against EBV-associated diseases, most notably nasopharyngeal carcinoma, commonly observed in Malaysians would have to be administered to infants 6-12 months of age.

Matched MeSH terms: Herpesviridae Infections/immunology*
Fulltext Human herpes virus 8 antibodies in HIV-positive patients in Surabaya, Indonesia

Oktafiani D, Megasari NL, Fitriana E, Nasronudin, Lusida MI, Soetjipto

Infect Dis Rep, 2020 07 07;12(Suppl 1):8746.
PMID: 32874472 DOI: 10.4081/idr.2020.8746

Background: Human herpesvirus 8 (HHV-8) infection is etiologically related to Kaposi's sarcoma. Antibodies directed against HHV-8 can be detected in 80-95% of HIV-seropositive patients with KS. HHV-8 serological tests have been done in several countries in Southeast Asia such as Malaysia, and Thailand however no serological data is available in Indonesia. This study was to examine the presence of HHV- 8 antibodies in HIV-positive patients in Surabaya, Indonesia.
Material and methods: Ninety-one serum samples were collected from HIVpositive patients in Surabaya, Indonesia. Human immunodeficiency virus-positive serum samples were collected from 10 homosexual men, 25 intravenous drug users (IVDUs) and 56 heterosexuals. Serums were then tested for the presence of HHV-8 antibody by using sandwich ELISA (Abbexa Ltd, Cambridge, UK).
Results: The total of 91 HIV-infected were testing with antibodies to HHV-8 using enzyme-linked immunosorbent assay. Antibodies of HHV-8 were detected in 7/91 (7.7%) of the samples. According to a gender, six men (85.7%) and a women (14.3%) were positive of HHV-8 antibodies. No correlation regarding the gender and age from this study. The antibodies of HHV-8 was detected among intravenous drug users (IVDUs) men 5/7 (42.8%) and 2/7 (28.6%) from homosexual and heterosexual, respectively.
Conclusion: This study found the presence of HHV-8 antibodies in 7.7% of patients in Surabaya, Indonesia. This finding was higher more than Southeast Asian countries. The patients with a positive result could suggest measures to prevent HHV-8 infection.

Matched MeSH terms: Herpesviridae Infections
Active human Herpesvirus-6 infections and associated diseases

Yadav, M.

Malaysian Journal of Child Health, 1991;3(1):11-22.
MyJurnal

Human Herpesvirus-6 (HHV-6) infections are ubiquitous in human populations with an antibody prevalence of 30-85 percent in normal adults. The virus in vivo infects T-lympho-cytes, at various stages of differentiation and is cytopathic to host cell during productive infection. In culture the virus is pleiotropic for several established cell lines including T and B lymphocytes, macrophages and neural cells. Primary viral infection occurs mostly in early childhood. The saliva is the primary source of infection. The infection remains clinically silent in majority but it establishes a lifelong latent presence. However, in about 30 percent of infants, probably a varient HHV-6, causes exanthem subitum (roseola infantum). If the primary infection of HHV-6 is delayed until adolescence it is accompanied by clinical manifestation of an Epstein-Barr virus like infectious mononucleosis in some individuals. Depressed host immune functions may reactivate the latent HHV-6 infection and further aggravation of the primary disease. Since the virus is cytopathic to the host cell the presence of HHV-6 in AIDS patients and other lympholiferative disorders may increase the severity and pathogenicity of the primary disease. Antibodies to the HHV-6 are enhanced in autoimmune disorders, chronic fatigue syndrome, progressive lymphoroliferative disorders and organ transplant patients on immunosuppressive drugs therapy. While considerable basic immunovirological information has been obtained in the last 4 years, large gaps in knowledge still exist on the biologic interaction of HHV-6 with the host.

Matched MeSH terms: Herpesviridae Infections
Identification of potential hot spots in the carboxy-terminal part of the Epstein-Barr virus (EBV) BNLF-1 gene in both malignant and benign EBV-associated diseases: high frequency of a 30-bp deletion in Malaysian and Danish peripheral T-cell lymphomas

Sandvej K, Peh SC, Andresen BS, Pallesen G

Blood, 1994 Dec 15;84(12):4053-60.
PMID: 7994023

In this study, we have sequenced the C-terminal part of the Epstein-Barr virus (EBV)-BNLF-1 gene encoding for the latent membrane protein-1 from tissues of EBV-positive Danish Hodgkin's disease (HD) and of Danish and Malaysian peripheral T-cell lymphomas (PTLs) and from tonsils of Danish infectious mononucleosis (IM). Our study showed that some of the 7 single-base mutations and the 30-bp deletion previously detected between codons of amino acid 322 and 366 in the BNLF-1 gene of the nasopharyngeal carcinoma cell line CAO were present in all Malaysian PTLs and in 60% of the Danish PTLs. In HD and the IM cases, the mutations were present in about 30%. The 30-bp deletion and the single base mutations occurred independently, and mutations were detectable in the majority of EBV type B-positive cases. These findings suggest that the 30-bp deletion and the 7 single-base mutations in the C-terminal part of the CAO-BNLF-1 gene do not characterize a new EBV type A substrain. Rather, some of the positions of single base mutations and the 30-bp deletion are hot spots that may have mutated independently through the evolution of EBV strains.

Matched MeSH terms: Herpesviridae Infections/microbiology*
Human herpesvirus-6 (HHV-6) DNA and virus-encoded antigen in oral lesions

Yadav M, Arivananthan M, Chandrashekran A, Tan BS, Hashim BY

J Oral Pathol Med, 1997 Oct;26(9):393-401.
PMID: 9385576

Archival oral tissues comprising 51 squamous cell carcinomas, 18 non-malignant lesions and 7 normal mucosa samples were investigated for human herpesvirus-6 (HHV-6)-encoded antigens and HHV-6 DNA. The virus-specific antigens were detected by an immunohistochemical method using monoclonal antibodies. Two further techniques used for HHV-6 DNA detection included the polymerase chain reaction (PCR) with virus-specific primers and in situ hybridization using digoxigenin-labelled oligonucleotides specific for HHV-6A and HHV-6B genotypes. A high proportion (79-80%) of the squamous cell carcinomas were positive for HHV-6 with the various detection methods. In cases of lichen planus and leukoplakia a high prevalence rate (67-100%) was noted with in situ hybridization and immunohistochemical techniques but a lower proportion (22-33%) was detected with the PCR method. All 7 normal tissues tested were negative for HHV-6. The HHV-6 variant B was found in 60% of the oral carcinoma tissues analysed. The study demonstrates the frequent presence of HHV-6 in neoplastic and non-malignant lesions of the oral cavity. While the role of HHV-6 in oral mucosal tissues remains to be determined, the in vitro tumorigenic potential of the virus suggests a possible role in the etiopathogenesis of oral lesions.

Matched MeSH terms: Herpesviridae Infections/virology
Epstein-Barr virus latent membrane protein-1 oncogene deletions: correlations with malignancy in Epstein-Barr virus--associated lymphoproliferative disorders and malignant lymphomas

Kingma DW, Weiss WB, Jaffe ES, Kumar S, Frekko K, Raffeld M

Blood, 1996 Jul 01;88(1):242-51.
PMID: 8704180

LMP-1, an Epstein-Barr viral (EBV) latency protein, is considered a viral oncogene because of its ability to transform rodent fibroblasts in vivo and render them tumorigenic in nude mice. In human B cells, EBV LMP-1 induces DNA synthesis and abrogates apoptosis. LMP-1 is expressed in EBV-transformed lymphoblastoid cell lines, nasopharyngeal carcinoma (NPC), a subset of Hodgkin's disease (HD), and in EBV-associated lymphoproliferative disorders (EBV-LPDs). Recently, focused deletions near the 3' end of the LMP-1 gene (del-LMP-1, amino acids 346-355), in a region functionally related to the half-life to the LMP-1 protein, have been reported frequently in human immunodeficiency virus (HIV)-associated HD (100%) and EBV+ Malaysian and Danish peripheral T-cell lymphomas (100%, 61% respectively), but less frequently in cases of HD not associated with HIV (28%, 33%) and infectious mononucleosis (33%). To further investigate the potential relationship of del-LMP-1 to EBV-LPDs associated with immunosuppression or immunodeficiency, we studied 39 EBV-associated lymphoproliferations (10 benign, 29 malignant) from four distinct clinical settings: posttransplant (4 malignant, 1 reactive); HIV+ (18 malignant, 2 reactive); nonimmunodeficiency malignant lymphoma (ML) (7 cases); and sporadic EBV infection with lymphoid hyperplasia (7 cases). The presence of EBV within lymphoid cells was confirmed by EBV EBER1 RNA in situ hybridization or by polymerase chain reaction (PCR) analysis. EBV strain type and LMP-1 deletion status were determined by PCR. EBV strain types segregated into two distinct distributions: HIV+ (9 A; 11 B) and non-HIV (19 A, 0 B), consistent with previous reports. Overall, del-LMP-1 were found in 1 of 5 (20%) Burkitt lymphomas (BL); 17 of 24 (71%) aggressive non-Hodgkin's lymphoma (agg-NHL), and 2 of 10 (20%) reactive lymphoid proliferations. Of the agg-NHLs, del-LMP-1 were present in 4 of 4 PT-ML (100%); 10 of 15 HIV+ ML (67%); and 3 of 5 nonimmunodeficiency malignant lymphoma (ML, 60%). A total of 2 of 7 (28%) sporadic EBV-associated lymphoid hyperplasias contained a del-LMP-1. All del-LMP-1 were identical by DNA sequence analysis. No correlation was identified between the presence of del-LMP-1 and the EBV strain type observed. The high incidence of del-LMP-1 observed in agg-NHLs (71%), in contrast to the relatively low incidence observed in reactive lymphoid proliferations (28%), suggests that the deleted form may be preferentially selected in lymphomatous processes. All posttransplant agg-NHLs contained a del-LMP-1, and a similar frequency of del-LMP-1 was observed in both HIV-associated ML (66%) and nonimmunodeficiency ML (60%), suggesting that impairment of immune function alone is not a requirement for the expansion of malignant cells infected by EBV stains containing the deleted LMP-1 gene.

Matched MeSH terms: Herpesviridae Infections/virology*
Detection of human herpesvirus 7 in salivary glands

Yadav M, Nambiar S, Khoo SP, Yaacob HB

Arch Oral Biol, 1997 Aug;42(8):559-67.
PMID: 9347118

The prevalence and cellular distribution of human herpesvirus 7 (HHV-7) in archival labial salivary glands was analysed for virus-specific DNA sequences by polymerase chain reaction (PCR) and in situ hybridization signals. In addition, the cellular expression of HHV-7-encoded protein was detected by immunohistochemical staining with a virus-specific monoclonal antibody. Eleven of 20 samples were positive for the HHV-7 DNA sequence by PCR. Eighteen of 20 tissues analysed by in situ hybridization showed signals in ductal, serous and mucous cells. Some nuclei of these cells and also the myoepithelial population were positive. In immunolocalization studies, all 20 salivary glands consistently showed HHV-7-expressed protein in the cytoplasm of ductal cuboidal and columnar cells. The protein was also found in the cytoplasm of mucous and serous acinar cells that were immunopositive for HHV-7. The observations are consistent with the suggestion that the labial salivary gland is a site for virus replication, potential persistence and a source of infective HHV-7 in saliva.

Matched MeSH terms: Herpesviridae Infections