Epstein-Barr virus infection in sinonasal non-Hodgkin's lymphomas

Sinonasal non-Hodgkin's lymphomas (SNHLs) of B- or T-cell immunophenotype have been associated with Epstein-Barr virus (EBV) infection of neoplastic lymphoid tissue. Nine SNHLs were investigated using immunohistochemistry, the polymerase chain reaction (PCR) for EBV genome and in situ hybridization (ISH) for EBV encoded RNAs (EBER), immunoglobulin (CI-gHR) and clonal T-cell receptor (CTCR) gene rearrangements. Eight cases were diagnosed as peripheral pleomorphic T-cell lymphomas (pPTCL). PCR showed the presence of EBV genome in eight cases; ISH for EBER led to the detection of positive cells in five cases. Late membrane protein (LMP) immunostaining was observed in three cases. No EBV positivity has been detected in control cases. The frequent association with EBV infection in the cases illustrated confirms the previous suggestions that EBV may have a role in the genesis of lymphomas of the sinonasal region.     

High frequency of Epstein–Barr virus in Chinese peripheral T-cell lymphoma

Forty-two cases of Chinese T-cell lymphoma were studied for expression of Epstein–Barr virus (EBV) encoded RNA (EBER-1) and EBV latent membrane protein-1 (LMP-1) using in situ hybridization and immunohistochemistry, respectively. EBV was detected in tumour cells in 24/39 peripheral T-cell lymphomas (62%), comprising 18/27 pleomorphic, medium and large cell lymphomas (67%), 4/6 angioimmunoblastic lymphadenopathy-like lymphomas (67%), 2/2 Lennert's lymphomas, 0/2 anaplastic large cell lymphomas, and 0/2 T-zone lymphomas. EBV was not found in three T-lymphoblastic lymphomas. EBV was associated with 12/24 nodal (50%) compared with 12/15 extranodal (80%) peripheral T-cell lymphomas. In EBV positive nodal lymphomas, 9/12 cases (75%) contained less than 10% EBER positive tumour cells. In EBV positive extranodal lymphomas, 9/11 cases (82%) showed EBV gene expression in more than 50% of the tumour cells, and in five of these almost all tumour cells were positive. Lymphomas of the nasopharynx (mainly midline granuloma-type) showed EBER-1 expression in nearly all tumour cells. LMP-1 was detected in 19/23 EBER positive peripheral T-cell lymphomas (83%). Our results show that EBV is strongly associated with peripheral T-cell lymphomas in Chinese. An important role for the virus is suggested in lymphomas of the nasopharynx. The significance of EBV in T-cell lymphomas that contain only a minor population of virally infected tumour cells is currently unclear.     

Characteristics of Epstein-Barr virus associated childhood non-Hodgkin’s lymphoma in the Republic of Korea

To analyze the clinicopathologic characteristics of childhood non-Hodgkins lymphoma (NHL) associated with Epstein-Barr virus (EBV), EBER in situ hybridization was performed in 80 cases of NHLs. EBER-positive lymphomas account for 25% (20/80) and include NK/T-cell lymphoma (6/6), aggressive NK-cell leukemia (1/1), peripheral T cell lymphoma (5/11), diffuse large B-cell lymphoma (5/14), hydroa-like T-cell lymphoma (1/1), marginal zone B-cell lymphoma (1/2), and post-transplantation lymphoproliferative disorder (1/1). Other types including 19 cases of Burkitts lymphoma were negative. For 9 EBER-positive cases, immunohistochemical staining for LMP-1, and EBNA-2 was performed to determine the EBV latency pattern. Two of nine EBER-positive cases expressed both LMP-1 and EBNA-2. Clinically, patients with EBV-positive B-cell lymphomas were cured with chemotherapy, whereas EBV-associated NK- and T cell lymphomas pursued fatal clinical course. In conclusion, EBVs infected in childhood NHLs are frequently associated not only with NK- and T- cell lymphomas but also large B-cell lymphomas.     

Epstein–Barr virus in Reed–Sternberg G-like cells in non Hodgkin's lymphomas

In the course of our study on Hodgkin's disease (HD), ten cases of non-Hodgkin's lymphomas (NHL) containing Hodgkin and Reed-Sternberg-like (MRS) cells were encountered. Many of these cases had initially been diagnosed as HD, but on careful review of the histology, with the aid of immunophenotyping studies, they were reclassified as NHL. The presence of Epstein–Barr virus (EBV) in these HRS-like cells was investigated using a combination of EBER in situ hybridization (ISH) and immunostaining for the detection of EBV-encoded latent membrane protein (LMP). HRS-like cells in four cases (two lymphoplasmacytoid lymphomas, one Richter's transformation of lymphoplasmacytoid lymphoma, and one immunoblastic lymphoma of T-cell type) were found to be EBV-positive. In two of these cases, a second biopsy taken up to 10 years later also contained EBV in the HRS-like cells. In three of the four cases, HRS-like cells expressed the activation antigen CD30, but the expression of B- or T-cell antigens was variable. All cases of T-cell-rich B-cell lymphomas were negative for EBV. In conclusion, EBV may play a role in the development of HRS-like cells i some cases of NHL. The relationship of HRS-like cells to HRS cells of HD is discussed.     

Epstein-Barr virus in nasal T-cell lymphomas (polymorphic reticulosis/midline malignant reticulosis) in Western China

Polymorphic reticulosis (PR) or midline malignant reticulosis (MMR) is considered to be malignant, or at least pre-malignant T-cell proliferations of the nose or midline area. Recent reports of small series of nasal T-cell lymphomas have shown a strong association with Epstein-Barr virus (EBV). Furthermore, a peculiar phenotype is described, with expression of CD56 and not of CD3, suggesting a possible origin from natural killer (NK) cells. We have analysed a series of 38 cases of PR/MMR for the presence of EBV by in situ hybridization (ISH) of the EBV-encoded RNAs 1 and 2 (EBER). Twenty cases were tested for expression of EBV-encoded latent membrane protein 1 (LMP-1). Special attention was also paid to the expression of CD3 and the NK cell-related marker CD56. Thirty-two cases (84 per cent) showed positive EBER ISH. In 5 of 20 cases, LMP-1 expression was detected. In three cases, a few scattered cells were positive, and in two cases, LMP-1 was detected in clusters of atypical cell. Most of the neoplasms showed expression of CD3 (89 per cent) and in 27 cases (71 per cent), CD56 was detected. These results are consistent with an aetiopathogenetic role for EBV in most, but not all, cases of PR/MMR. Our findings are less supportive of a major role for LMP-1 in tumour genesis. CD3 expression in most of the cases of PR/MMR underlines the T-cell origin of these neoplasms, often with aberrant expression of CD56.     

Distribution and ZAP-70 expression of WHO lymphoma categories in Shanxi, China: a review of 447 cases using a tissue microarray technique.

This study aims to assess the distribution of lymphoma subtypes in Shanxi, China, according to the World Health Organization (WHO) classification, and to compare the relative distribution with other areas of the world. H&E-stained tissue sections from the archives of the Shanxi Tumor Hospital, China, were reviewed and 447 cases with sufficient materials were selected for detailed study. A panel of antibodies and probes was assembled, including antibodies to ALK1, bcl-6, CDs 1alpha, 3, 4, 5, 7, 8, 10, 15, 20, 23, 30, 43, 56, 68, 79alpha, and 99, cyclin D1, EMA, kappa, lambda, LMP1, PAX5, TdT, Vs38C and ZAP70, plus EBER RNA probe by in situ hybridization. The 447 lymphoma cases, subtyped according to the WHO classification, were assembled in triplicate into 11 tissue microarrays and examined with the panel of markers described. Among the 447 cases, 385 (82.6%) were confirmed to be non-Hodgkin lymphomas (NHL) and 62 (13.9%) were Hodgkin lymphomas of classic type (CHL). Of the NHL cases, 68.6% were B-cell lymphomas and 30.6% T/NK-cell lymphomas. Histiocytic neoplasms accounted for only three cases (0.8%). Diffuse large B-cell lymphomas (DLBCL) were the most common subtype (35.1%), followed by peripheral T-cell lymphomas unspecified (PTun, 12.0%), extranodal marginal zone B-cell lymphomas (MALT lymphomas, 11.7%), follicular lymphomas (FL, 8.6%), T-lymphoblastic lymphomas (T-LBL, 7.0%), anaplastic large cell lymphomas (ALCL, 4.2%), B small lymphocytic lymphomas (B SLL, 3.6%), and mantle cell lymphomas (MCL, 2.6%). Of 263 B-cell neoplasms, 105 (39.9%) expressed immunoglobulin light chain, including 52 kappa and 53 lambda, detectable in paraffin sections. The incidence of DLBCL was similar to many Western countries and Asia. The frequency of FL was, however, much lower than the usual pattern in Western countries, although NK/T-cell lymphomas were more common (30.6%), similar to other countries in Asia, including Japan and Korea. With regard to markers of EBV infection, 8 of 385 (2.1%) NHL cases gave positive findings by both in situ hybridization (EBER RNA) and immunohistochemistry (LMP-1), whereas 24 (6.2%) expressed only the EBER and 12 (3.1%) expressed only LMP-1. EBV positivity was found in 24 of 119 (20.2%) T and NK cell lymphomas, in 20 of 263 (7.6%) B cell neoplasms, and in 37 of 62 (59.7%) CHLs. In CHLs there was complete concordance of results by both in situ hybridization (EBER RNA) and immunohistochemistry (LMP-1) procedures. ZAP70 was detected in most T cell-lineage disorders (61.4%) and also in a subset of B small lymphocytic lymphomas (50%). However, ZAP-70 was expressed in a minority of other types of B-cell lymphomas, including precursor B-cell acute lymphoblastic leukemia (25%), diffuse large B-cell lymphoma (26.7%), follicular lymphoma (15.2%), and lymphoplasmacytic lymphoma (9.1%). Immunohistochemical analysis represents an effective method for assessing ZAP-70 expression and reveals that a variety of B-cell malignant neoplasms express ZAP-70, albeit at low frequency.     

Detection of Epstein–Barr virus nucleic acid sequences and protein in nodal T-cell lymphomas: relation between latent membrane protein-1 positivity and clinical course

Forty-six nodal T-cell lymphomas, classified according to the updated Kiel classification, were investigated for the presence of Epstein–Barr virus (EBV) DNA by polymerase chain reaction (PCR), EBER 1 and 2 (EBER 1/2) and latent membrane protein-1 (LMP-1) expression. A combination of RNA in situ hybridization and immunohistochemistry was used to establish the phenotype of the Epstein–Barr virus harbouring cells. In 21 of 45 cases Epstein–Barr virus DNA sequences could be detected with the polymerase chain reaction. In 15 cases (14 of 21 EBV PCR positive cases), EBER 1/2 positive cells could be demonstrated. As judged by morphology, EBER 1/2 expression was found in non neoplastic and neoplastic lymphoid cells. Double staining revealed that more than 80% of the EBER 1/2 harbouring cells, lacked B-, T- or histiocytic markers, suggesting down regulation of T- and B-cell markers by Epstein–Barr virus. In eight of 15 cases some EBER 1/2 positive T-cells (CD3, CD45RO, CD43) morphologically resembling tumour cells were found. In nine of 14 cases tested EBER 1/2 positive non-neoplastic B-cells (CD20) were seen. Based on in situ hybridization results, four patterns of EBER 1/2 positive cells were found, i.e. single cells (≤1 per medium power field (mpf), n = 3), scattered (1–25/mpf, n = 4), clustered (26–100/mpf, n = 5) and diffuse (≥100/mpf, n = 3). In eight of 15 cases a clustered or diffuse pattern of EBER 1/2 positive cells was found and these lymphomas were therefore considered to be strongly associated with Epstein–Barr virus. In these lymphomas LMP-1 expression was found to be associated with an aggressive clinical course and hepatosplenomegaly.     

High frequency of EBV association and 30-bp deletion in the LMP-1 gene in CD56 lymphomas of the upper aerodigestive tract

Natural killer (NK)/T-cell lymphomas are frequently associated with Epstein-Barr virus (EBV), and usually lack TCR gene rearrangement. Studies from Asia have reported frequent deletion in the LMP-1 gene in EBV-associated nasopharyngeal carcinoma (NPC). The present study aims to investigate LMP-1 and TCRgamma gene status in upper aerodigestive tract lymphomas. A total of 43 cases were classified into T-, B-, and NK/T-cell tumors based on the phenotype expressions of CD3(+)/CD20(-)/CD56(-), CD3(-)/CD20(+)/CD56(-), and CD3(+)/CD20(-)/CD56(+), respectively. The presence of EBV in the tumor was confirmed by EBV early RNA-in situ hybridization. LMP-1 gene deletion and TCR gamma gene rearrangement were analyzed by polymerase chain reaction on paraffin-embedded tissues. There were 20 NK/T-, eight T-, and 15 B-cell phenotype lymphomas in the present series, and EBV was detected in 19 (95%), two (25%), and three (20%) cases in the respective groups. All EBV+ cases carried 30-bp deletion in the LMP-1 gene, and two of the NK/T-cell cases were infected by both the wild type and deleted strains. Five (25%) of the NK/T-cell phenotype lymphomas showed rearranged TCR gamma gene. The present study revealed a high frequency of EBV association, and a high frequency of 30-bp deletion in the LMP-1 gene in the virus in the present series of lymphoma. The NK/T-phenotype lymphomas are comprised of both NK-cell and cytotoxic T-lymphocyte-derived tumors.     

Increased number of Epstein-Barr virus latently infected B-cells in T-cell non-Hodgkin's lymphoma tissues

Summary Epstein-Barr virus (EBV) is a causative agent of malignant lymphomas occurring in immunocompromised hosts. Similar lymphoid tumors can be induced in mice with severe combined immunodeficiency (SCID mice) by transplanting human B-cells with latently infected EBV. We have previously observed that when apparently EBV-negative lymphomas were engrafted into SCID mice, 11 of 18 T-cell non-Hodgkin's lymphomas (NHLs) produced EBV associated lymphomas, but only 2 of 30 engrafted with B-NHLs. Previous studies suggested that EBV-infected cell inducing lymphomas in SCID mice may preferentially exist in T-cell NHL tissues. To prove this assumption, in situ hybridization (ISH) using oligonucleotide probes for EBV-encoded small RNAs 1 (EBER1) was used in this study to demonstrate EBV-bearing lymphocytes in NHL tissues. It was found that EBV-bearing cells existe in 9 of the 10 T-cell NHL surgical specimens. By contrast, in B cell NHLs, only 2 of 10 carried EBV-bearing cells. Further semi-quantitative analysis demonstrated that apparently significantly more EBV-bearing cells were present in T-cell NHL tissues than in B-cell NHLs. Moreover, these EBV-bearing cells in lymphoma tissues were shown to be of B-cell lineage, by the combinated analysis of immunostaining with CD20 and ISH with EBER1. These results indicated the increase of EBV-bearing B-cells in T-cell NHL tissues, suggesting the activation of B-cells with latently infected EBV by neoplastic T-cells.     

Primary natural killer/T-cell lymphomas of the oral cavity are aggressive neoplasms

Thirty-four cases of primary non-Hodgkin’s lymphoma of the oral cavity were investigated for their clinical findings, histopathological features, immunophenotypes and association with Epstein-Barr virus (EBV). Four cases (12%) were natural killer/T-cell lymphomas, 3 (9%) were T-cell lymphomas and 27 (79%) were B-cell lymphomas. Compared with T- and B-cell lymphomas, NK/T-cell lymphomas had a male predominance (M:F 4:0), and most presented as ulceration of the palate and/or maxillary gingiva. Histologically, the lesions showed diffuse infiltration of medium-sized or large lymphoid tumour cells. Angiocentricity and/or angioinvasion were found in all 4 cases. The immunophenotypes of the NK/T-cell lymphomas were CD3+, CD43+, CD45RO+, CD56+ and TIA-1+. EBV was detected in 2 NK/T-cell lymphomas by in situ hybridization (ISH) and polymerase chain reaction (PCR) methods, and was not detected in T- and B-cell lymphomas. The survival rate of patients with NK/T-cell lymphoma was zero, but the survival rates for patients with T-cell and B-cell lymphomas were 67% and 38%, respectively. It appears that NK/T-cell lymphomas of the oral cavity have a predilection for originating in the palate and maxillary gingiva and are aggressive neoplasms. EBV positivity might be associated with more aggressive behaviour. Received: 21 January 1999 / Accepted: 14 April 1999     

Lymphomas of the oral cavity: histology, immunologic type, and incidence of Epstein-Barr virus infection

The purpose of this study was to determine the histologic class and immunologic phenotype of lymphomas presenting initially in the oral cavity and whether this correlated to a high incidence of Epstein-Barr virus (EBV) infection as has been reported with lymphomas in the nasal cavity. Seventy-one cases of oral lymphomas from the oral pathology referral service were analyzed retrospectively. They were classified according to the Revised European American Lymphoma (REAL) classification system using routine immunohistochemistry. EBV infection was determined by detection of early viral RNA sequences (EBER) and latent membrane protein (LMP-1) expression. Only non-Hodgkin's lymphomas were observed, with a female predominance of 2:1. They were primarily of B-cell origin and histologically classified mainly as large B-cell type (68%); T-cell lymphomas were rare (8%). EBV infection was observed in 14% of the B-cell lymphomas, an incidence rate higher than that reported in studies of B-cell lymphomas not located in the oral cavity but not as high as that observed in pleomorphic T-cell lymphomas (all sites, 36%) or nasal cavity T-cell lymphomas (nearly 100%). Interestingly, EBV proliferation did not correlate with expression of either Bcl-2 or p53.     

Epstein–Barr virus-associated primary gastrointestinal lymphoma in non-immunocompromised patients in Korea

We examined 81 cases of primary gastrointestinal lymphomas in Korea, including 64 gastric lymphomas and 17 intestinal lymphomas, for EBV expression by EBER-1 in situ hybridization (ISH) and EBNA-1 PCR. In EBER-1 positive cases, we performed immunohistochemistry for latent membrane protein-1 (LMP-1) and EBV diffuse early antigen (EA(D)) to compare EBV latent gene expression and lytic process.   EBER-1 was detected in 15 of 81 cases of lymphomas. EBER-1 expression showed three different patterns on tumour cells; diffuse 4/81 (5%), localized 4/81 (5%), and a few scattered pattern 7/81 (9%). We regarded diffuse pattern and localized pattern as EBER-1 positive group (8/81: 10%). Diffuse pattern of EBER-1 was shown in all three T-cell lymphomas and one B-cell lymphoma. A localized pattern was seen all in B-cell lymphomas. The EBER-1 expression was 11% in the stomach (7/64) and 6% in the intestine (1/17). Five of the eight EBER-1 positive gastric lymphomas were histologically diffuse large B-cell lymphomas, and the other three were peripheral T-cell lymphoma, unspecified, one angiocentric lymphoma, and one intestinal T-cell lymphoma by REAL classification. Eight MALT type gastric B-cell lymphomas showed no EBV association. EBV nuclear antigen (EBNA-1) was detected in 15 of 45 resected cases (33%) by PCR. EBER-1 positive cases were all EBNA-1 positive. Twelve EBNA-positive/EBER-negative cases consisted of seven cases showing a few scattered EBER-1 positive lymphocytes. LMP-1 and diffuse early antigen (EA(D)) was detected in five and three cases, respectively. Although follow-up information in our series was incomplete, it seemed that there was no significant difference in their staging or prognosis between EBER-positive cases and EBER-negative group. It is concluded that EBV is associated with some lymphomas among Koreans without overt pre-existing immunodeficiency, especially in T-cell lymphomas.     

上呼吸道淋巴瘤的病理,免疫表型及其与EB病毒相关性的研究

目的研究中国北方人上呼吸道淋巴瘤的临床病理学、免疫表型及与ＥＢ病毒的关系。方法应用单克隆抗体ＵＣＨＬ１、Ｌ２６、４ＫＢ５及ＣＳ１４进行免疫组化染色,ＥＢ病毒寡核苷酸探针（ＥＢＥＲ１／２）原位杂交,观察１１２例上呼吸道淋巴瘤的免疫表型及ＥＢ病毒感染情况。结果１１２例上呼吸道淋巴瘤病例中７７例为Ｔ细胞淋巴瘤（６８８％）。３５例为Ｂ细胞淋巴瘤（３１．３％）。ＥＢＶＥＢＥＲ１／２原位杂交１０１例中５４例阳性,各例中阳性细胞占肿瘤细胞的１５０％～８５０％,阳性病例中Ｔ细胞淋巴瘤４８例（８８９％）,Ｂ细胞淋巴瘤６例（１１１％）。结论中国北方人上呼吸道淋巴瘤以Ｔ细胞淋巴瘤为多见,且与ＥＢ病毒有较高的相关性。     

EBV in situ hybridization study for non-Hodgkin's lymphomas.

Epstein-Barr virus(EBV) has been implicated in the pathogenesis of B-lymphoproliferative disorders, T-cell lymphomas and Hodgkin''s disease. In this report, we performed an in situ hybridization study on EBV genome in 10 cases of nasal non-Hodgkin''s lymphoma(NHL), 20 cases of Waldeyer''s ring(WR) NHL, and 20 cases of nodal NHLs to document EBV association with lymphomas in Koreans. For immunophenotyping, monoclonal antibodies for CD 20, MB 2, CD 45Ro & CD 43 were used. For in situ hybridization study, EBV DNA probe for Bam HI ''V'' fragment and EBV RNA probe for EBER and BHLF were used. Twenty two cases(44%) of malignant lymphomas were positive for EBV genome. Generally, T-cell lymphomas showed a higher positive rate(61%) than B-cell lymphomas(24%). Among T-cell lymphomas, nasal lymphomas showed a higher positive rate(80%) than WR(50%) or nodal lymphomas(50%). Of 22 EBV genome positive cases, 10 cases were positive for EBER, 10 cases for BHLF, and 2 cases for both EBER and BHLF. The histologic types by Working Formulation(WF) were not correlated with EBV genome positive rate, whereas lymphomas showing the histologic spectrum of polymorphic reticulosis(PR) showed a higher positive rate(65%) than lymphomas without PR-like features(40%). These results indicate that nasal T-cell lymphomas with the histologic spectrum of PR are strongly associated with EBV and that the anatomic site may be an important factor in this association.     

Cytotoxic protein expression in natural killer cell lymphomas and in αβ and γδ peripheral T-cell lymphomas

Lymphomas with T-cell phenotype represent a heterogeneous group of diseases differing in histopathology, tumour site, and cell origin. They include peripheral T-cell lymphomas (PTCLs) derived from αβ cells, but also some recently recognized entities such as γδ hepatosplenic lymphomas and natural killer (NK) cell lymphomas. Only a few studies have investigated the possibility that at least some PTCLs could be derived from lymphocytes with cytotoxic potential. In order to investigate this possibility, 60 cases of PTCL, including 27 cases expressing the αβ T-cell receptor (TCRαβ), 15 TCRγδ cases and 18 cases expressing neither TCR (TCR silent), as well as 14 cases of NK-cell lymphomas, were studied by immunohistochemistry for the expression of TIA-1, perforin, and granzyme B proteins. Expression of TIA-1 is characteristic of cytotoxic cells regardless of their activation status, whereas expression of perforin and granzymes is highly increased in activated cytotoxic cells and correlates with the induction of cytolytic activity. All NK-cell lymphomas (11 sinonasal, three systemic cases) expressed TIA-1, perforin, and granzyme B in most tumour cells. All γδ PTCLs (15 cases) expressed TIA-1 protein in most tumour cells, with a different cytotoxic antigen profile in hepatosplenic γδ PTCL (TIA-1+, perforin−, granzyme B−) and in non-hepatosplenic γδ PTCLs (three nasal, one skin, one lung), the latter expressing the three cytotoxic proteins. Of the 45 cases of αβ and TCR silent PTCL, 15 (33 per cent) were considered to be derived from cytotoxic lymphocytes with expression of at least one cytotoxic protein (TIA-1, 15/45; perforin, 10/41; granzyme B, 14/38) in tumour cells. This cytotoxic protein expression appeared to be related to the site of localization, since 7/13 (54 per cent) extranodal and only 8/32 (25 per cent) nodal αβ and TCR silent PTCLs expressed TIA-1, and to histology, since this pattern was observed in a proportion of anaplastic (6/8, 75 per cent) and pleomorphic (8/17, 47 per cent) lymphomas, but not in AILD-type NHL (0/16). Taken together, our data suggest that NK-cell lymphomas and non-hepatosplenic γδ PTCLs represent tumours of activated cytotoxic NK cells and γδ T cells, respectively; that hepatosplenic γδ PTCLs represent tumours of non-activated cytotoxic γδ T cells; and that a small proportion of αβ and TCR silent PTCLs, mostly extranodal cases, or nodal anaplastic lymphomas, represent tumours of cytotoxic T cells. © 1997 John Wiley & Sons, Ltd.     

A survey of Epstein-Barr virus gene expression in sporadic non-Hodgkin''s lymphomas. Detection of Epstein-Barr virus in a subset of peripheral T-cell lymphomas.

This study analyzes the association of Epstein-Barr virus (EBV) with non-Hodgkin's lymphoma (NHL) arising in patients without pre-existing overt immunodeficiency. The authors examined 201 lymphomas (105 high-grade B-cell, 82 peripheral T-cell, 7 high-grade non-B-cell, non-T-cell, and 7 hairy-cell leukemia) for EBV gene expression by immunohistologic procedures using monoclonal antibodies to EBV latent, immediate early, and replicative infection antigens. Transformation-associated EBV latent membrane protein 1 (LMP 1) was detected in 13 (6%) NHL, comprising 4 (4%) high-grade B-cell, 8 (10%) peripheral T-cell, and 1 non-B-cell, non-T-cell lymphomas. Anaplastic large-cell lymphoma of T-cell type was consistently LMP 1-negative. EBV nuclear antigen 2 was demonstrated in only three (1%) cases. Induction of replication as defined by expression of the immediate early BamHI Z leftward reading frame 1 (BZLF1) protein was detected in five cases, but early (EA) and late (VCA and MA) lytic cycle antigens were only found in two cases and in one case, respectively. The presence of EBV was confirmed by in situ DNA hybridization in 9 of 11 EBV antigen-positive lymphomas. This study shows the surprisingly frequent presence of EBV in peripheral T-cell NHL in European patients without pre-existing overt immunodeficiency. Interestingly, most sporadic B-cell NHL are not associated with the virus. Furthermore, the usefulness of selected monoclonal antibodies for the routine immunohistological diagnosis of EBV infection was confirmed.     

Frequent detection of Epstein–Barr virus-infected B cells in peripheral T-cell lymphomas

Although Epstein–Barr virus (EBV) positivity has been described in peripheral T-cell lymphomas (PTCLs) in Chinese patients, the cellular lineage of EBV-harbouring cells is unknown. Forty-four cases of PTCL were therefore studied by in situhybridization (ISH) for EBV-encoded small non-polyadenylated RNA 1 and 2 (EBER), and the lineage of the EBER+ cells was determined by double labelling. The findings were further correlated with the clonality of EBV and the genotype of these EBER+ tumours. The results for the detection of EBV by ISH show that 23 of the 44 cases were EBER+. In 5/23 of the EBER+ cases, EBER was found in around 50 per cent of atypical cells and in 18/23 cases, EBER was found in a subpopulation of atypical cells. Amongst the EBER+ cases, all 15 tested showed clonal T-cell receptor gene rearrangement by Southern blot hybridization. Double labelling was successfully done in 11 EBER+ cases, and by comparison, EBER+/CD20+ B cells outnumbered the EBER+/CD3+ T cells in all these cases. EBV clonality analysis revealed that EBV was monoclonal in six EBER+ cases and biclonal in three cases. With the predominance of EBV+ B cells over EBV+ neoplastic T cells being observed in most of these cases, it is possible that the EBV-infected clonal population may be of B-cell lineage. This was supported in some cases where a faint clonal band was seen over a background smear in the gene rearrangement study of immunoglobulin heavy chain gene by polymerase chain reaction (PCR), indicating a minor B-cell clone. It is concluded that in EBV+ PTCL, EBV is preferentially localized in B cells rather than neoplastic T cells. The neoplastic T cells may support the clonal proliferation of a subpopulation of EBV+ B cells in PTCLs. © 1998 John Wiley & Sons, Ltd.     

Prevalence of Epstein-Barr virus in non-Hodgkin's lymphomas in central region of Tunisia

The purpose of this study was to evaluate the prevalence of EBV in non-Hodgkin's lymphomas occuring in non-immunocopromised patients in Tunisia through a series of 126 cases. EBV was investigated by EBER oligonucleotide in situ hybridization (ISH) and LMP1-immunohistochemistry. Serological study of EBV has been performed before therapy in 28 patients. EBV was detected in tumor cells by ISH in 28/126 (22.2%) cases. Variable proportions of tumor cells were positive. LMP1 was identified in only 8 cases. EBV was more frequently observed in T-cell lymphomas (9/24 patients; 37.5%) than in B-cell lymphomas (19/102 patients; 18.6%) (p=0.04). There was a strong relationship between EBV and small intestine lymphomas (6/8 patients; 75%) and T/NK nasal type lymphomas (3/3 patients; 100%). EBV serological reactivation was noted in 7/13 patients in clinical stages III/IV and in only 1/10 patients in stages I/II (p=0.03). In conclusion, the prevalence of EBV in Tunisian non-Hodgkin's lymphomas is low but variable depending on the histological type and anatomical location with a predilection for small intestine and nasal lymphomas.     

Biology and adoptive cell therapy of Epstein-Barr virus-associated lymphoproliferative disorders in recipients of marrow allografts

Summary: Epstein-Barr virus (EBV) is an ubiquitous herpesvirus which is carried as a latent infection of B lymphocytes and salivary gland epithelial cells in over 90% of normal adults. Latently infected IBV-transformed B cells circulate at low frequency in the blood for the life of the host. These transformed B cells stimulate a heterogeneous and complex host cell response, ultimately leading to the development and maintenance of high frequencies of HLA-restricted T cells specific for the EBV-encoded nuclear antigens EBNA2–EBNA6 and the latency membrane proteins LMP-1 and LMP-2. Responses to latent EBV-encoded proteins are hierarchical with responses to certain epitopes predominating, dependent upon the HLA genotype of the host. Profound suppression of T-Cell immunity may permit the emergence of polyclonal, oligoclonal or monoclonal EBV antigen-expressing lymphoproliferative disorders or malignant B-cell lymphomas expressing these latent EBV antigens. Adoptive transfer of small numbers of peripheral blood mononuclear cells or HLA-partially matched T cells from in vitro expanded EBV-specific T-cell lines derived from a seropositive marrow donor has induced durable regressions of bulky, widely metastatic monoclonal EBV lymphomas in a high proportion of cases. This review describes the current state of knowledge and hypothesis regarding the biology and immunology of EBV infection in the normal host, the features of donor, host and virus which contribute to the development of EBV-associated lymphoproliferative diseases and the mechanisms whereby they are controlled by adoptive transfer of immune T cells.