Epstein-Barr virus as an agent of haematological disease

Analysis of the relationship between the expression of EBV-related antibodies and ET-1 axis in gastric cancer

BACKGROUND AND OBJECTIVE: EBV-associated gastric cancer (EBVaGC) is a distinct subtype of GC, and EBV plays an important role in tumor progress. The standard method to identify EBV-positive tumor is determined by in situ hybridization for EBV-encoded EBERs in tumor tissues. The present study aims to detect the serological expression of EBV-related antibodies and ET-1 axis to provide a noninvasive method for diagnosis of EBVaGC. METHODS: The content of EBV-related antibodies and ET-1 axis in preoperative peripheral blood of GC was performed by Chemiluminescence and ELISA assay. The EBV DNA copy number was measured by qRT-PCR. RESULTS: The results showed that the levels of anti-EBV early antigen (EA) IgG, viral capsid antigen (VCA) IgA, nuclear antigen (NA) IgG, and EBV DNA copy number were significantly higher in EBVaGC. The ET-1 axis level was much lower in EBVaGC than EBVnGC. CONCLUSIONS: The combined detection of specific anti-EBV antibodies and ET-1 axis might provide new molecular markers for the identification of EBVaGC.

Successful Treatment of Necrotizing Retinitis with Epstein-Barr Virus-Positive Ocular Fluid by Intravitreal Methotrexate Injection

PURPOSE

To present a case of necrotizing retinitis with Epstein-Barr virus (EBV)-positive ocular fluid in a patient with sudden unilateral vision loss, which was successfully treated with intravitreal methotrexate (MTX) injections.

METHODS

Retrospective case report.

RESULTS

An 83-year-old female who had been on methylprednisolone for 20 years due to interstitial pneumonia developed vitreous opacity and extensive necrotizing retinitis with retinal hemorrhage sparing the posterior pole in the left eye. Multiplex polymerase chain reaction (PCR) for viral DNA using vitreous sample was positive for EBV but negative for herpes simplex virus, varicella-zoster virus, and cytomegalovirus. Real-time PCR detected EBV-DNA in aqueous humor but not in peripheral blood sample. Serologic testing was negative for Toxoplasma gondii, syphilis, and HIV. The patient did not respond to systemic ganciclovir or acyclovir. Subsequent treatment with intravitreal MTX resulted in immediate clinical improvement correlating with a decrease in copy number of EBV-DNA.

CONCLUSION

Intravitreal MTX may be an effective treatment option for patients with necrotizing retinitis and EBV-positive ocular fluid not responding to conventional antiviral therapy.

Characterization of Epstein-Barr virus (EBV)-infected cells in EBV-associated hemophagocytic lymphohistiocytosis in two patients with X-linked lymphoproliferative syndrome type 1 and type 2

BACKGROUND

X-linked lymphoproliferative syndrome (XLP) is a rare inherited immunodeficiency by an extreme vulnerability to Epstein-Barr virus (EBV) infection, frequently resulting in hemophagocytic lymphohistiocytosis (HLH). XLP are now divided into type 1 (XLP-1) and type 2 (XLP-2), which are caused by mutations of SH2D1A/SLAM-associated protein (SAP) and X-linked inhibitor of apoptosis protein (XIAP) genes, respectively. The diagnosis of XLP in individuals with EBV-associated HLH (EBV-HLH) is generally difficult because they show basically similar symptoms to sporadic EBV-HLH. Although EBV-infected cells in sporadic EBV-HLH are known to be mainly in CD8+ T cells, the cell-type of EBV-infected cells in EBV-HLH seen in XLP patients remains undetermined.

METHODS

EBV-infected cells in two patients (XLP-1 and XLP-2) presenting EBV-HLH were evaluated by in EBER-1 in situ hybridization or quantitative PCR methods.

RESULTS

Both XLP patients showed that the dominant population of EBV-infected cells was CD19+ B cells, whereas EBV-infected CD8+ T cells were very few.

CONCLUSIONS

In XLP-related EBV-HLH, EBV-infected cells appear to be predominantly B cells. B cell directed therapy such as rituximab may be a valuable option in the treatment of EBV-HLH in XLP patients.

EBV, HHV8 and HIV in B cell non Hodgkin lymphoma in Kampala, Uganda

BACKGROUND

B cell non Hodgkin lymphomas account for the majority of lymphomas in Uganda. The commonest is endemic Burkitt lymphoma, followed by diffuse large-B-cell lymphoma (DLBCL). There has been an increase in incidence of malignant lymphoma since the onset of the HIV/AIDS pandemic. However, the possible linkages of HHV8 and EBV to the condition of impaired immunity present in AIDS are still not yet very clearly understood.

OBJECTIVES

1. To describe the prevalence of Epstein-Barr virus, Human Herpes virus 8 and Human Immunodeficiency Virus-1 in B cell non Hodgkin lymphoma biopsy specimens in Kampala, Uganda.2. To describe the histopathology of non Hodgkin lymphoma by HIV serology test result in Kampala, Uganda

METHOD

Tumour biopsies specimens from 119 patients with B cell non Hodgkin lymphoma were classified according to the WHO classification. Immunohistochemistry was used for detection of HHV8 and in situ hybridization with Epstein Barr virus encoded RNA (EBER) for EBV. Real time and nested PCR were used for the detection of HIV.The patients from whom the 1991-2000 NHL biopsies had been taken did not have HIV serology results therefore 145 patients biopsies where serology results were available were used to describe the association of HIV with non Hodgkin lymphoma type during 2008-2009.

RESULTS

In this study, the majority (92%) of the Burkitt lymphomas and only 34.8% of the diffuse large B cell lymphomas were EBV positive. None of the precursor B lymphoblastic lymphomas or the mantle cell lymphomas showed EBV integration in the lymphoma cells.None of the Burkitt lymphoma biopsies had HIV by PCR. Of the 121 non Hodgkin B cell lymphoma patients with HIV test results, 19% had HIV. However, only 1(0.04%) case of Burkitt lymphoma had HIV. All the tumours were HHV8 negative.

CONCLUSIONS

The majority of the Burkitt lymphomas and two fifths of the diffuse large B cell lymphomas had EBV. All the tumours were HHV8 negative. Generally, the relationship of NHL and HIV was weaker than what has been reported from the developed countries. We discuss the role of these viruses in lymphomagenesis in light of current knowledge.

Infectious mononucleosis with secondary cold agglutinin disease causing autoimmune haemolytic anaemia

This case report describes a 20-year-old woman whose initial clinical, laboratory, and radiological presentation suggested obstructive jaundice. However, she was subsequently found to be suffering from autoimmune haemolytic anaemia resulting from an Epstein-Barr virus infection complicated by cold agglutinin disease. The patient went on to make a complete clinical recovery after discharge.

Pattern of Epstein-Barr virus association in childhood non-Hodgkin's lymphoma: Experience of University of Malaya Medical Center

The pattern of childhood non-Hodgkin's lymphoma (NHL) usually differs in adults. The most common subtypes are lymphoblastic, Burkitt's and anaplastic large cell lymphoma. Recent data indicate that a higher risk of developing lymphoma is associated in children of certain ethnic origins. The difference is probably related to the underlying etiological factors of these diseases, and Epstein-Barr virus (EBV) is a strong candidate. The present study aims to determine the disease pattern of childhood lymphomas in the University Hospital Kuala Lumpur, for a direct comparison to the reported data of adults from the same medical center. A total of 69 and 34 childhood NHL and Hodgkin's lymphomas, respectively, were retrieved. The most common subtypes were lymphoblastic (23 cases), Burkitt's (25 cases) and anaplastic large cell lymphomas (9 cases). Epstein-Barr virus association was more prevalent in B-cell (23%) than T-cell (12%) lymphomas. The most common EBV-associated tumor was Burkitt's lymphoma, and there was an increased risk of EBV association for Burkitt's lymphoma in Chinese patients. In conclusion, the pattern of childhood lymphoma in Malaysia is relatively similar to children elsewhere in the world. The EBV association of B- and T-NHL differs between children and adults from the same medical center because of differences in the subtype composition in these two age groups.

Epstein-Barr virus-associated T-/natural killer cell lymphoproliferative diseases

Epstein-Barr virus (EBV) is a ubiquitous virus that infects the majority of the world population by adulthood. The major target for infection is the B lymphocyte, and acute infection causes vigorous EBV-specific killer T-cell responses exemplified clinically by acute infectious mononucleosis (IM). EBV infection usually persists latently life-long without eliciting any clinical symptoms. Rarely, active EBV infection is prolonged, with abnormal expansions of EBV-infected T or NK cells, conditions collectively defined here as EBV-associated T/NK lymphoproliferative diseases. Hemophagocytic lymphohistiocytosis (HLH), chronic active EBV infection (CAEBV), NK lymphoma/leukemia, and T-cell lymphoma are entities included in this category. Hypersensitivity to mosquito bite (HMB) represents a unique syndrome characterized by expansion of EBV-infected NK cells in the peripheral circulation and within the inflammatory skin lesions induced by mosquito bites. Target cell specificity, defects in host immune responses, and strain differences of EBV may account for ectopic EBV infections and for the unique clinical presentations characteristic of each illness.

Diagnosis of Epstein-Barr virus-associated diseases

Epstein-Barr virus (EBV) is a common DNA virus distributed worldwide. Usually the initial infection involves the upper respiratory tract without any problems and almost the entire population more than 25 years old test positive for anti-EBV antibodies. However, EBV often causes not only acute lytic infection but also chronic active infection with B cells and even T cells. In addition the EBV genome has been detected in tumors of hematopoietic or epithelial cell origin such as Burkitt's lymphomas, Hodgkin's disease, NK/T cell lymphomas, nasopharyngeal carcinomas (NPCs) and gastric adenocarcinomas. It is clearly important to make a correct diagnosis for EBV associated diseases and monitor the EBV load in individual patients for an appropriate therapy. In this paper recent advances in serological, immunological and molecular approaches for detection of EBV associated disease are described.

Epstein-Barr virus detection in non-Hodgkin's lymphoma of the oral cavity: an immunocytochemical and in situ hybridization study

OBJECTIVE

The purpose of this study was to histologically characterize a series of oral non-Hodgkin's lymphomas (NHLs) and to investigate latent and lytic Epstein-Barr virus (EBV) infection in these.

STUDY DESIGN

The revised European-American Lymphoma classification system (41) was used to categorize 58 cases of oral NHL, which included 9 immunosuppression-related NHLs. EBV infection was determined by in situ hybridization for Epstein-Barr virus-encoded RNA and by immunohistochemistry for the EBV antigens latency membrane protein, Epstein-Barr nuclear antigen-2 (EBNA2) and Z EBV replication activator protein.

RESULTS

Most tumors were B-cell lymphomas (78%), but the proportion of T-cell lymphomas was surprisingly high (22%). The most common histologic subtypes were diffuse large B-cell lymphomas (45%), peripheral T-cell lymphomas (19%), and follicle center lymphomas (14%). Two thirds of the known immunosuppression-related NHLs were T-cell lymphomas. All of the immunosuppression-related tumors were EBV-infected, whereas the EBV infection rate in the NHLs of the remaining patients presumed to be immunocompetent was only 9%. Most EBV-positive tumors expressed neither of the latent antigens (ie, latency membrane protein and Epstein-Barr nuclear antigen-2), and coexpression of the 2 was observed only in immunosuppressed patients. Z EBV replication activator protein expression, which is indicative of replicative infection, occurred only in immunosuppressed individuals.

CONCLUSIONS

Diffuse large B-cell lymphomas were the most common histologic subtype of oral NHLs, but T-cell lymphomas were relatively common and frequently occurred in states of immunosuppression. EBV may play a limited role in the initiation of lymphoma in the immunocompetent patient, but the virus may be of importance in progression of the disease in those patients with more aggressive tumors, as immunosuppression occurs.

EBV-NK cells interactions and lymphoproliferative disorders

Epstein-Barr virus (EBV) usually infects epithelial cells in the oropharynx and B lymphocytes asymptomatically. Occasionally, however, EBV infects T-cells and natural killer (NK) cells, and infection of these cells has been associated with the development of leukemias and lymphomas. EBV-positive lymphoproliferative disorders of NK cells have been reported with increasing frequency, but the interactions between EBV and NK cells are not fully understood, in part because NK cells are not usually infected with EBV in vitro. The lymphoma-derived EBV-positive NK cell line, YT, has been useful in the study of EBV infection of NK cells. YT cells express the EBV-associated nuclear antigen (EBNA)-1, the latent membrane protein (LMP)-1, and LMP-2A, but not EBNA-2 and LMP-2B genes. This pattern of latent gene expression is compatible with a type II latency program, normally associated with nasopharyngeal carcinoma, Hodgkin's disease, and T-cell lymphoma. In this report, we summarize recent information on EBV-NK cell interactions and EBV-positive lymphoproliferative disorders of NK cells.

A study of the possible etiologic association of Epstein-Barr virus with reactive hemophagocytic syndrome in Hong Kong Chinese

The herpes group of viruses, particularly Epstein-Barr virus (EBV), has frequently been implicated in the causation of reactive hemophagocytic syndrome (RHS) in the Western populations. EBV has also been implicated in the rare fulminant form of RHS occurring in Oriental children. However, our previous adult-predominant study indicated little clinical and serological evidence of EBV infection in patients with RHS in Hong Kong. In the present study, we further examined this issue using a more sensitive and specific technique for the demonstration of EBV, ie, in situ hybridization for EBV encoded RNA (EBER). The 43 Chinese patients studied were mostly adults with a mean age of 44 years, and a male to female ratio of 1.5:1. About two-thirds (28) of patients had associated malignant lymphoma at the time of diagnosis. Five patients had documented infection (typhoid fever 2; systemic candidiasis 1; adenovirus pneumonia 1; viral encephalitis 1), and two had systemic lupus erythematosus. EBER signals were detected in only 11 cases (25.6%). All positive cases were associated with malignant lymphoma, and the positive signals were exclusively localized to the lymphoma cells but not in the histiocytes. On comparing the results (11 of 28 cases positive; 39.3%) with our previous data on EBER-expression in malignant lymphomas in Hong Kong, no significant difference is observed in the frequency of EBV-positivity between the two groups of lymphomas. Thus, a definite pathogenetic link between EBV and lymphoma-associated RHS cannot be established. However, the overrepresentation of T and T/NK lineage lymphoma in this sample of lymphoma-associated with RHS (61%) versus nonselected cases of lymphomas (31%) suggests that it is the T and T/NK cell origin of the lymphoma rather than the EBV positivity that predisposes to RHS. Notwithstanding the previous findings, EBER in situ hybridization may still serve as a useful adjunct in the investigation of patients with RHS, because the presence of EBER-positive cells should raise a strong suspicion of an underlying malignant lymphoma.