Helper virus induced T cell lymphoma in nonhuman primates after retroviral mediated gene transfer.

Moloney Murine Leukemia Virus (MoMuLV) causes T cell neoplasms in rodents but is not known to be a pathogen in primates. The core protein and enzyme genes of the MoMuLV genome together with an amphotropic envelope gene are utilized to engineer the cell lines that generate retroviral vectors for use in current human gene therapy applications. We developed a producer clone that generates a very high concentration of retroviral vector particles to optimize conditions for gene insertion into pluripotent hematopoietic stem cells. This producer cell line also generates a much lower concentration of replication-competent virus that arose through recombination. Stem cells from rhesus monkeys were purified by immunoselection with an anti-CD34 antibody, incubated in vitro for 80-86 h in the presence of retroviral vector particles with accompanying replication-competent virus and used to reconstitute recipients whose bone marrow had been ablated by total body irradiation. The retroviral vector genome was detected in circulating cells of five of eight transplant recipients of CD34+ cells and in the circulating cells of two recipients of infected, unfractionated bone marrow mononuclear cells. Three recipients of CD34+ cells had a productive infection with replication-competent virus. Six or seven mo after transplantation, each of these animals developed a rapidly progressive T cell neoplasm involving the thymus, lymph nodes, liver, spleen, and bone marrow. Lymphoma cells contained 10-50 copies of the replication-competent virus, but lacked the retroviral vector genome. We conclude that replication-competent viruses arising from producer cells making retroviral vectors can be pathogenic in primates, which underscores the importance of carefully screening retroviral producer clones used in human trials to exclude contamination with replication-competent virus.

Death caused by possible unrecognized (too Late Recognized) Mycobacterium gordonae infection in a patient with angioimmunoblastic T-cell lymphoma.

Here, we present possible death caused by Mycobacterium gordonae infection in a patient with angioimmunoblastic T-cell lymphoma. Our patient was severely immunocompromised in whom we suspect to an infection, but we did not have isolates until she died. After she died, we received a positive sputum culture of M. gordonae. We conclude that when having severely immunocompromised patients with suspicion of infection but without isolates we should always consider the saprophytic mycobacteria. These mycobacteria require a long period of isolation, but patients with these mycobacteria are potentially curable if appropriate treatment is applied for a sufficiently long period.

Listeria monocytogenes in a young patient with non Hodgkins lymphoma: case report.

Listeria monocytogenes is an intracellular food-borne pathogen, widely distributed in the environment, which rarely causes clinical infection in healthy people, but may cause severe disease in immunocompromised patients. A case of listeriosis is certified in an immunocompromised patient, thus confirming this microorganism to be an opportunistic human pathogen.

Quantitation, in vitro propagation, and characterization of preleukemic cells induced by radiation leukemia virus.

Intrathymic (i.t.) inoculation of radiation leukemia virus into C57BL/6 mice induces a population of preleukemic (PL) cells that can progress into mature thymic lymphomas upon transfer into syngeneic recipients. A minimum of 10(3) PL thymic cells are required to induce lymphomas in the recipient. Most of the individual lymphomas developed in mice which were inoculated with cells of a single PL thymus, derived from different T-cell precursors. PL thymic cells could be grown in vitro on a feeder layer consisting of splenic stromal cells. Growth medium was supplemented with supernatant harvested from an established radiation leukemia virus-induced lymphoma cell line (SR4). The in vitro-grown PL cells were characterized as Thy-1+, CD4+, CD8- T-cells, most of which expressed radiation leukemia virus antigens. Cultured PL cells were found to be nontumorigenic, based on their inability to form s.c. tumors. However, these cells could develop into thymic lymphomas if inoculated i.t. into syngeneic recipients. A culture of PL cells, maintained for 2 mo, showed clonal T-cell receptor arrangement. Lymphomas which developed in several recipient mice upon injection with these PL cells were found to possess the same T-cell receptor arrangement. These results indicate that PL cells can be adapted for in vitro growth while maintaining their preleukemic character.

Lymphomagenesis in AKR.Fv-1b congenic mice.

In the AKR.Fv-1b congenic strain the Fv-1n allele of the AKR/J mice was substituted with the Fv-1b allele, thereby limiting viral replication and spread of the endogenous N-tropic murine leukemia virus. As a result of this genetic change AKR.Fv-1b mice develop a low spontaneous incidence (7%) of T-cell lymphomas and about 28% of Ly-1+ B-cell lymphomas are observed in old mice. Characteristic changes in thymus subpopulations of AKR/J mice (related to the formation of the dual tropic mink cell focus inducing (MCF) type virus in the thymus) were not observed in the thymus of AKR.Fv-1b mice. In contrast to the low susceptibility to spontaneous T-cell lymphoma development, these mice were highly sensitive to fractionated irradiation or to radiation leukemia virus (a mixture of N- and B-tropic viruses) induced T-cell lymphoma. Potential lymphoma cells (that would ultimately develop into Ly-1+ B-cell lymphomas) were demonstrated in bone marrow and spleens of 16-24-month-old mice. Analysis of the Ly-1+ IgM+ B-cell population in spleens of 18-month-old mice revealed a significant increase in this population (35% versus 2% in young spleens). The spontaneous Ly-1+ B-cell lymphoma incidence could be enhanced (up to 77%) by in vivo administration of anti-CD8 monoclonal antibody or IL-4 to 18-month-old mice. Virological analysis of T/B-cell lymphomas for class I MCF viruses indicated that Class I MCF development was tightly correlated with T-lymphoma development (except radiation induced tumors that showed no MCF provirus involvement). In contrast, Ly-1+ B-cell lymphoma development was independent of Class I MCF pathogenic virus involvement.

Detection and characterization of T-cell leukemia virus-like proviral sequences in PBL and tissues of baboons by PCR.

The "high lymphoma-prone" baboon stock (Papio hamadryas) of the Sukhumi Primate Center colony is characterized by a high prevalence of antibodies to the STLV-I/HTLV-I type of retrovirus and a high manifestation of human ATL-type (adult T-cell leukemia/lymphoma) malignancies (Yakovleva et al., this symposium). This is in contrast to other primate colonies and wild monkeys, which have low seroprevalence and very few if any ATL-type T-cell malignancies. To characterize the type of T-cell lymphoma retrovirus involved in the Sukhumi disease, a PCR (polymerase chain reaction) DNA analysis of peripheral blood lymphocytes (PBL) and of various tissues of healthy "at-risk", or ill baboons was performed. Proviral STLV/HTLV sequences were detected in all monkeys with symptoms of T-cell malignancy and/or antibodies to STLV-I/HTLV-I. For precise identification and characterization of the Sukhumi T-cell lymphoma virus, parts of the virus genome were mapped and sequenced from PCR derived fragments. A 420 nucleotide fragment of the env (gp 46) gene (analysed from 3 different DNA's) revealed 16.2% nucleotide divergence to the Japanese strain of HTLV-I and 14.8% to the Japanese strain of STLV-I including one deletion of a triplet. On the level of amino acid (a.a) sequence this revealed an exchange of 6 a.a. to STLV-I (4.3%), but only of 4 a.a. to HTLV-I (2.8%). The analysis of 120 nucleotides of the tax sequence (identical in 6 different DNAs) resulted in 5% nucleotide divergence to the HTLV-I (2.4% on the a.a. level) and 10% (7.3% a.a.) to the STLV-1. These results indicate that the Sukhumi T-cell lymphoma virus is a representative of the T-cell leukemia/lymphoma virus family, apparently more closely related to HTLV-I than to STLV-I genome. Furthermore, the infected monkeys from Sukhumi develop at a high rate a T-cell malignancy not observed among other baboons carrying STLV.

Influence of amphipathic peptides on the HIV-1 production in persistently infected T lymphoma cells.

The effects of several amphipathic peptides on HIV-1 production in persistently infected cells are described. Melittin, a 26 amino acid alpha-helical amphipathic peptide, reduces HIV-1 production dose-dependently, whereas other amphipathic peptides do not. Six melittin derivatives which retain the alpha-helical portion have similar effects as melittin. The reduction of viral infectivity is not due to an effect of melittin on the virus particles but to an intracellular action of the peptide, which is readily taken up into cells, as shown by quantitative ELISA. Western blots of cells from melittin-treated cultures suggest that the processing of the gag/pol precursor is impaired.

Epstein-Barr virus (EBV) genomes and EBV-encoded latent membrane protein (LMP) in pulmonary lymphomas occurring in nonimmunocompromised patients.

Recently, in situ hybridization (ISH) techniques have shown that Epstein-Barr virus (EBV) could be detected in tumor cells of most angiocentric T-cell non-Hodgkin's lymphomas (NHL). These studies included only a few cases of T-NHL of the lung and pulmonary B-NHL and have not been investigated. Furthermore, the expression of the EBV-encoded latent membrane protein (LMP), which is known for its oncogenic properties, has not been reported. Twelve pulmonary NHL (six angiocentric T-NHL and six B-NHL) arising in nonimmunocompromised patients were examined for the presence of EBV-EBER mRNAs and LMP with ISH and immunohistochemistry, respectively. Four cases of pulmonary lymphomas arising in immunocompromised patients were also included in the study for comparison (one T-NHL in a patient under immunosuppressive treatment and three B-NHL in AIDS patients). EBV-RNA and LMP were detected in tumor cells in two of six nonimmunocompromised angiocentric T-NHL and in the four immunocompromised NHL. The six nonimmunocompromised B-NHL were EBV negative. These results suggest that EBV is associated with some angiocentric pulmonary T-NHL arising in patients without overt immunodeficiency whereas it is absent in such patients with B-NHL. The presence of the transforming EBV-encoded LMP in tumor cells suggests that EBV may be involved in the pathogenesis of some pulmonary T-NHL.

Diverse classes of T-cell lymphomas arise in T-lymphocyte-inductive epitheliomas of the mouse salivary gland.

During the course of serial transplantations of polyomavirus-induced C3H-Bittner salivary gland epitheliomas in F1-hybrid mice, three tumor sublines were found which gave rise to T-cell lymphomas of host origin. The lymphomas resembled spontaneous AKR/J thymic lymphomas in their expression of lymphoid differentiation antigens, and they may represent sequential stages in the differentiation of immature T lymphocytes. We found no evidence that polyomavirus directly induced the lymphomas, rather, the lymphomagenic events paralleled those which occur in spontaneous AKR/J thymic lymphomas.

Growth regulation of a T-cell lymphoma via the T-cell receptor.

Autocrine stimulation is described for a Radiation leukaemia virus (RadLV)-induced T-cell lymphoma, C6VL/1. The proliferation of this tumour cell line can be regulated by several agents, including interleukin-2 (IL-2), antibodies to the IL-2 receptor and the T-cell antigen-specific receptor (TCR), as well as RadLV retrovirus particles produced by the cell itself. This information has been gained using various procedures to slow or arrest C6VL/1 proliferation, including the addition of gamma interferon (gamma-IFN) and cell culture at low density. All data suggest that these cells can receive growth stimulation via the T-cell receptor (TCR) and IL-2 receptor, implicating autocrine stimulation of growth involving IL-2 and retroviral gene products.

Polymorphic reticulosis: a reappraisal.

We studied 18 patients (15 men and three women) evaluated for a destructive sinonasal lesion that had been diagnosed as "polymorphic reticulosis." The histologic features of each lesion were those of angiocentric immunoproliferative lesions," characterized by atypical lymphoid infiltrates with polymorphous, angiocentric, and necrotic features; 13 were grade 2 and five were grade 3. The neoplastic cells in each patient had a T-cell phenotype. Epstein-Barr virus RNA was detected in the neoplastic cells of 17 of the 18 T-cell lesions. Initial treatment consisted of local radiation therapy in each patient, chemotherapy in two patients, and prednisone in another patient. Two patients were lost to follow-up and the other 16 had a median follow-up of 14 years, 2 months (range, 4 months to 32 years, 5 months). Four patients are alive and disease free, four patients died not of disease or complication of therapy, and eight patients died of disease. The Kaplan-Meier estimate of survival was 63% at 5 years and 50% at 15 years. Histologic progression of angiocentric immunoproliferative lesions from grade 2 to grade 3 was observed in two patients, and a correlation between angiocentric immunoproliferative grade and survival could not be detected. These data suggest that polymorphic reticulosis is an Epstein-Barr virus-related angiocentric T-cell lymphoma.

In situ localization of Epstein-Barr virus encoded RNA in non-nasal/nasopharyngeal CD56-positive and CD56-negative T-cell lymphomas.

We recently reported a group of non-nasal/nasopharyngeal hematolymphoid malignancies expressing the natural killer cell marker CD56, characterized by frequent extranodal localization, angiocentricity, and aggressive clinical course (HUM PATHOL 23:798-804, 1992). Because we have shown a very strong association of Epstein-Barr virus (EBV) with CD56-positive T-cell lymphomas of the nose nasopharynx, we asked whether a similar association also occurs with the non-nasal CD56-positive T-cell lymphomas. In situ localization of EBV encoded RNA (EBER) was performed on paraffin sections of 15 such cases, including the nine previously reported cases and six new cases (three showing prominent hepatosplenic involvement and three showing involvement of one or more extranodal sites, such as the parotid gland, tonsils, gastrointestinal tract, skeletal muscle, and testis). A case was considered positive when the majority of the tumor cells showed nuclear signal. Ten cases showed EBER positivity, and all but one of them were negative for CD3 and other T-cell markers, except CD2. Only one of four cases showing a CD3-positive phenotype was EBER positive. Of the remaining two CD3-negative EBER-negative cases, one showed a histiocytic phenotype and the other was positive for multiple T-cell markers. Among 15 cases of CD56-negative non-nasal peripheral T-cell lymphoma studied for comparison, six were CD3-negative, among which three showed EBER positivity. All nine CD3-positive cases were EBER negative. Five cases (three CD3 positive and two CD3 negative) showed rare isolated (< 1%) EBER-positive tumor cells. We conclude that among non-nasal T-cell lymphomas, EBV is strongly correlated with CD56 positivity (66.7% v 20%), and the positive cases almost always show an immunophenotype identical to that commonly observed in nasal lymphomas (CD2 positive, CD3 negative, and CD56 positive). Thus, EBV may play an etiologic role in these CD56-positive lymphomas. There is also a correlation between EBER positivity and CD3 negativity, irrespective of the CD56 status. The presence of isolated EBER-positive cells in CD56-negative T-cell lymphomas, occurring at a frequency similar to that reported in the European population, probably represents secondary infection of tumor cells.

Type 2 Epstein-Barr virus genome and latent membrane protein-1 expression in a T-cell-rich lymphoma of probable B-cell lineage.

In a 79-year-old white woman, a lymphoproliferative disorder that was associated with type 2 Epstein-Barr virus (EBV) infection or reactivation, documented by three subsequent lymph node biopsies, was studied. After an initial phase with features of reactive lymphadenopathy with exhaustion of the follicular germinal centers and depletion of the B-cell lymphoid population, the disease evolved to a T-cell-rich lymphoma in which a clonal cell population of probable B-cell origin was identified. Such clonal cell population harbored the viral genome and expressed EBV latent membrane protein-1 but not EBV nuclear antigen-2. The implications of immunologic interactions between the clonal EBV-infected cells and the reactive T-cell component in the pathogenetic process are discussed.

Gamma/delta T-cell posttransplantation lymphoproliferative disorder primarily in the spleen.

A 31-year-old renal transplant recipient developed an unusual T-cell lymphoproliferative disorder 3 years after transplantation. The neoplasm involved the spleen, without concomitant hepatomegaly, lymphadenopathy, or obvious bone marrow involvement. Peripheral blood involvement developed after splenectomy. Immunophenotypically, the neoplastic cells expressed CD2, CD3, CD7, CD16, CD45, CD56, and the gamma/delta T-cell receptor on the surface membrane. The neoplastic cells were negative for surface membrane CD4, CD5, and CD8. Serologic and/or DNA analyses for viruses, including Epstein-Barr virus, human T-cell lymphotropic virus-1, human immunodeficiency virus, and human herpesvirus-6, were negative. Cytogenetic findings included a translocation breakpoint at chromosome 7p15, consistent with involvement of the T-cell receptor gamma-chain locus. Although gamma/delta T-cell lymphomas have been reported to have a predilection for hepatosplenic localization, this is the first well-documented case to be described in the setting of posttransplantation immunosuppression.

Detection of human cytomegalovirus in pleural fluid of lymphoblastic lymphoma T-cell type.

We report a case of T-lymphoblastic lymphoma in which lymphoma cells infected with cytomegalovirus were found in the pleural fluid. A 16-year-old boy with an anterior mediastinal mass developed pleural fluid accumulation. Immunoperoxidase staining of pathologic cells in the pleural fluid revealed them to be CD4+/-, CD7+, CD8-, CD34+, CD20- and HLA-DR+. The diagnosis of lymphoblastic lymphoma T-cell type was made. Electron microscopic examination revealed virus particles with an electron-dense core and capsid, late structures of virus, in the pleural fluid cells. Polymerase chain reaction (PCR) amplification was used to detect human cytomegalovirus (HCMV) DNA in pleural fluid cells. A pair of synthetic oligonucleotide primers from the CMV phosphoprotein 71, an early structural protein, coding region (HindIII fragments L, c and b of the Ad 169 strain) could amplify DNA from the pleural fluid cells from the patient. Immunoperoxidase staining of the pleural fluid cells with anti-HCMV positive sera also revealed a positive reaction. These findings suggest the entry of HCMV into lymphoma cells with positive PCR amplification of DNA encoding an early structural protein, and replication from the presence of late structures of virus, electron-dense core and capsid. Replication of lymphoid cell lines of B and T origin were reported in the literature but replication of HCMV in lymphoma cells in vivo has not been reported.

Cytotoxic T-cell lymphoma diffusely involving the entire gastrointestinal tract associated with Epstein-Barr virus and tubercle bacilli infection.

We describe a rare case of cytotoxic gastrointestinal T-cell lymphoma with protein-losing enteropathy. Initial examination revealed the coexistence of T-cell lymphoma and tuberculosis in the mesenteric lymph node and liver. Despite anti-tuberculosis and anti-cancer treatment, the patient experienced chronic diarrhea and malabsorption and died approximately 3 years after onset. Autopsy specimens revealed medium-sized lymphoma cells, with a phenotype of CD3+, CD4-, CD7+, CD8+, CD30-, CD56-, CD103 (HML-1)-, TIA-1+, and granzyme B+, proliferating primarily and consistently in the mucosa of the entire bowel tract from esophagus to rectum. Interestingly, Epstein-Barr virus (EBV)-encoded small nuclear RNAs were detected in the tumors by in situ hybridization. Southern blot analysis revealed monoclonal proliferation in the EBV-infected T cells. Although the present case can possibly be categorized as an intestinal T-cell lymphoma according to the Revised European-American Lymphoma Classification, the case showed a unique clinical course and distribution of lymphoma cells. We present here an interesting case of gastrointestinal cytotoxic T-cell lymphoma and examine the possible association with infectious agents.

Cytogenetic characterization of Epstein-Barr virus-associated T-cell malignancies.

Recently, Epstein-Barr virus (EBV) infection has been found not only to be associated with Burkitt lymphoma and nasopharyngeal carcinoma but also with some T-cell malignancies. Cytogenetic studies were performed on four Chinese patients with EBV-associated T-cell neoplasms: three peripheral T-cell lymphomas and one large granular lymphocyte leukemia with coexpression of T-cell antigen. Clonal chromosomal abnormalities were detected in all four patients. Rearrangements of chromosome 7 were observed in three patients: one at 7p22, one at 7q35 or 36, and the remaining one at both sites. The last patient also had a chromosomal abnormality involving 14q11. Trisomy of part of the 1q segment was detected in two patients. The results revealed that the chromosomal abnormalities in these patients were similar to those observed in other T-cell lymphomas. Further studies on more patients are necessary to find out whether there are specific chromosomal aberrations in EBV-associated T-cell neoplasms.

Primary intestinal non-Hodgkin's lymphoma and Epstein-Barr virus: high frequency of EBV-infection in T-cell lymphomas of Mexican origin.

Epstein-Barr virus is universally associated with endemic Burkitt's lymphoma (BL) and undifferentiated nasopharyngeal carcinoma and can be detected in a significant proportion of cases of Hodgkin's disease (HD) and peripheral T-cell lymphoma, but only rarely in sporadic B-NHL. The frequency of EBV-positivity in certain neoplasms shows important geographic variations. Both HD and sporadic BL from Latin America have shown higher rates of EBV-association than cases from Western countries. In T-NHL, the frequency of EBV-positivity is influenced by the site of the primary tumor and the phenotype of the neoplastic cells. Nasal and nasal-type T-NHL, which show a T/NK-cell phenotype with expression of CD56 are virtually always EBV-associated, whereas only a proportion of nodal, gastrointestinal and pulmonary T-NHL are EBV-infected. A recent investigation of primary intestinal lymphomas of Mexican origin demonstrated EBV-positivity in all examined cases of T-NHL and BL and a proportion of other B-NHLs. The presence of EBV was independent of the presence or absence of enteropathy. Two of 6 cases studied showed CD56 expression. The high rate of EBV-positivity independent of histologic subtype is in contrast to the low to intermediate rates of EBV-positivity found in cases of intestinal T-NHL from Western countries and indicates that geographic differences in the frequency of EBV-association of lymphoid neoplasms might also extend to a fraction of peripheral T-cell lymphomas.

Clinicopathological spectrum of Epstein-Barr virus-associated T cell malignancies.

It has been recently demonstrated that the Epstein-Barr virus (EBV) can infect human thymocytes and may be involved in the T cell neoplasms, in addition to African Burkitt's lymphoma, nasopharyngeal carcinoma and Hodgkin's disease. Four distinct clinicopathologic categories of EBV-associated T cell malignancies have been recognized. The angiocentric T cell lymphoma or lymphomatoid granulomatosis involving the nose (or midline lethal granuloma) and skin is frequently EBV-associated. The other 3 groups include angioimmunoblastic lymphadenopathy-like lymphoma, node-based T immunoblastic lymphoma which may contain Reed-Sternberg-like giant cells (Hodgkin's-like lymphoma), and T cell lymphoma resembling malignant histiocytosis. Both the CD4 and CD8 T cell subsets, and a hitherto undefined T lineage lacking CD4/CD8 expression have been involved. The common clinical features are prolonged fever, skin lesions, lymphadenopathy, hepatosplenomegaly, and pancytopenia. Serologic assays suggest that a chronic active EBV infection may exist in most of these patients. The EBV genomes appear to proliferate in clonal and episomal form in the neoplastic cells which show expression of latent membrane proteins. Although an indolent local phase may exist, the clinical course is aggressive for most patients with frequent development of drug resistance to conventional chemotherapy. EBV-associated T cell lymphoma constitutes a separate entity of virus-associated human diseases and opens a potential field to investigate the pathogenesis of EBV-associated human malignancies.