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T Aya

Publications and source records attributed to T Aya.

At least 19 recordsLinked to original sources
PubMed1993

High Epstein-Barr virus (EBV) susceptibility of both lymphoblastoid and lymphoma cell lines derived from a Japanese patient with EBV genome-positive Burkitt's lymphoma.

A Lymphoma cell line from the tumor tissue was established spontaneously from a Japanese patient with Epstein-Barr virus (EBV) genome-positive Burkitt's lymphoma (BL). Additionally lymphoblastoid cell lines from peripheral blood of this patient were established either spontaneously or by in vitro infection with B95-8 EBV. Lymphoma cells showed monoclonal surface immunoglobulins (kappa and gamma) with specific chromosomal translocations, t (8; 14). In contrast, lymphoblastoid cells expressed polyclonal surface immunoglobulins without specific chromosomal abnormalities. Lymphoma cells made colonies in soft agarose approximately 10 times more than those of the lymphoblastoid cells. When each cell line was cultured at lower temperature of 33 degrees C, treated with 12-O-tetradecanoyl- phorbol-13-acetate (TPA), and superinfected with P3HR-1 EBV, all cell lines expressed 5 to 10 times higher levels of EBV early antigens (EA) and viral capsid antigen (VCA) than lymphoblastoid cell lines from healthy controls. Furthermore, lymphoblastoid cell lines obtained from peripheral blood of this patient during the period of remission also exhibited high EA and VCA inducibility and superinfectibility. These findings suggested that the lymphoid cells in this patient were genetically highly susceptible to EBV infection, and this evidence possibly linked to the lymphomagenesis of EBV genome-positive BL.

Antibodies, Viral↗
PubMed1992

Frequent association of Epstein-Barr virus in Japanese patients with Burkitt's lymphoma.

Seven Japanese patients with Burkitt's lymphoma (BL), residing in Hokkaido, were studied during the period, 1979-1991. Immunological analyses of their lymphoma cells showed all to express surface and/or cytoplasmic immunoglobulins. Chromosomal analysis was performed in five cases. Four of the five lymphomas had the chromosomal translocation, t(8;14), and one had t(2;8). Three patients had extremely high IgG antibody titers to Epstein-Barr virus (EBV) viral capsid antigen (VCA) and to EBV early antigens (EA). Two patients had positive antibodies to EA, and two others had normal antibody patterns comparable to those of EBV-seropositive age- and sex-matched healthy controls. Four of the seven lymphomas (57.1%) were positive for EBV-determined nuclear antigen (EBNA) by anticomplement immunofluorescence and/or EBV DNA using DNA-DNA reassociation kinetics, and/or Southern blot analysis. The frequency of EBV positivity in BL patients residing in Hokkaido was higher than that of cases previously reported in Japan. Three of the four EBV genome-positive BL patients responded well to chemotherapy, radiotherapy and/or surgical treatment, with no significant relapse being observed during the study period. In contrast, EBV genome-negative patients had poor prognoses despite having similar levels of clinical staging at the time of diagnosis.

Adolescent↗
PubMed1992

[Chromosome and DNA analyses of peripheral blood lymphocyte from the quadruple cancer patient].

The patient with quadruple cancer was a 32 year-old female who had osteosarcoma, bilateral breast cancer and adenocarcinoma of the lung. When chromosomal analysis of peripheral blood lymphocyte was performed, two abnormal cells were detected among 42 cells examined. The first cell showed a translocation involving chromosome 1 and 20 and trisomic for chromosome 19. The second cell was trisomic for chromosome x. Southern blot analysis of DNA from peripheral blood lymphocyte revealed that there was no difference in the expression of Rb gene between the patient and healthy adult.

Adenocarcinoma, Papillary↗
PubMed1991

Chromosome translocation and c-MYC activation by Epstein-Barr virus and Euphorbia tirucalli in B lymphocytes.

Dual exposure to Epstein-Barr virus and purified 4-deoxyphorbol ester derived from the plant Euphorbia tirucalli induced a high frequency of chromosomal rearrangements in human B lymphocytes in vitro. Rearrangements most commonly affected chromosome 8, the chromosome most often showing structural changes in Burkitt's lymphoma (BL) cells. E tirucalli is indigenous in parts of Africa where BL is endemic and may be an important risk factor for the disease.

B-Lymphocytes↗
PubMed1991

An Epstein-Barr virus-producer line Akata: establishment of the cell line and analysis of viral DNA.

An Epstein-Barr virus (EBV)-producer line, designated Akata, was established from a Japanese patient with Burkitt's lymphoma. The Akata line possessed the Burkitt's-type chromosome translocation, t(8q- ; 14q+), and was derived from the tumor cell. Akata cells produced a large quantity of transforming virus upon treatment of cells with anti-immunoglobulin antibodies (Takada, 1984). Southern blot analysis of viral DNA indicated that the Akata EBV is nondefective and more representative of wild-type viruses. Akata cells should be useful as a source of EBV.

Antibodies, Viral↗
PubMed1986

Epstein-Barr virus infection and oncogenesis in primary immunodeficiency.

Lymphomas occurred in 3 of 16 Japanese patients with ataxia telangiectasia (AT) and Wiskott-Aldrich syndrome (WAS). The patients had a persistently reactivated Epstein-Barr virus (EBV) infection with a remarkable decrease in virus-specific cellular immunity. In these patients, the B lymphocytes were more sensitive to EBV-induced events and to cellular proto-oncogene activation than seen in the healthy counterparts. This immunologic and genetic background was considered to explain the massive lymphoproliferation in these primary immunodeficiency disorders.

Adolescent↗
PubMed1986

Epstein-Barr virus-enhancing plant promoters in east Africa.

The extracts of a certain African plant species, Euphorbia tirucalli, were found to have markedly enhancing effects on the activation of latent Epstein-Barr virus (EBV) genomes in the EBV carrying lymphoblastoid cells and also on EBV-induced transformation of human lymphocytes. The Euphorbia tirucalli was especially noticeable in highly endemic areas of Burkitt's lymphoma (BL), an EBV-associated malignancy, in Kenya and Tanzania. The activation of the latent EBV genome and the EBV-induced transformation enhancement were also observed with the soil and drinking water taken around the plants, strongly indicating that the people living in BL endemic areas are frequently exposed to such an EBV-enhancing plant promoter substance.

Africa, Eastern↗
PubMed1985

Establishment and characterization of Ph1-positive and Ph1-negative lymphoblastoid cell lines from a patient with chronic myelogenous leukemia.

Two continuously growing in vito cell lines, PB-1049 and LN-1049, were established from a patient with Ph1-positive chronic myelogenous leukemia in extramedullary blastic crisis. PB-1049 was established from Epstein-Barr virus (EBV)-infected peripheral lymphocytes of the patient and had a 46,XY,t(9;22) karyotype. This cell line was shown to be tumorigenic in nude mice, and cultured cells recovered from the tumor nodule showed a 46,XY,6p+,t(9;22) stem line karyotype. LN-1049 was derived from a lymph node culture of the same patient, and was found to be non-tumorigenic in nude mice and karyotypically normal. Immunological examinations on EBV-induced antigens, surface and cytoplasmic immunoglobulin, and monoclonal antibodies, and some enzymatic and electron microscopic studies revealed that both cell lines had attained differentiation into late-B cell stage.

Animals↗
PubMed1982

Evolution of infectious mononucleosis into Epstein-Barr virus carrying monoclonal malignant lymphoma.

A monoclonal malignant lymphoma was diagnosed in a 30-month-old Japanese boy, who, since the age of 12 months, had had chronic, recurrent infectious mononucleosis manifested by repeated episodes of severe cough and high fever accompanied by marked lymphadenopathy and hepatosplenomegaly and high serum Epstein-Barr virus (EBV) antibody titres. The diagnosis of Burkitt's lymphoma was made when a cervical lymph-node biopsy specimen revealed massive proliferation of immature B-cells with starry-sky histiocytes. These lymph-node cells were characterised by a translocation between chromosomes 10 and 17. There were approximately 9 EBV genome-equivalents per cell. Most cells were positive for nuclear antigen (EBNA); early antigen (EA) and viral capsid antigen (VCA) were also detected. The presence of EBV was supported by finding that the cell-free lymph-node extract transformed cord-blood lymphocytes into EBNA-positive blast cells. The proportion of EA-positive and VCA-positive cells increased rapidly in culture for 24 h, then the positive cells degenerated rapidly and completely. The cells also contained numerous herpes-type virus particles. The child improved considerably with cytostatic treatment and has been in remission for 2 years.

Antibodies, Viral↗
PubMed1981

[Immunologic protection against Epstein-Barr virus induced oncogenesis: cooperative effect of lymphocytes, antibodies and interferon in healthy individuals (author's transl)].

Immunologic cytotoxicity against lymphocytes transformed or infected by Epstein-Barr virus (EBV) was mainly studied in an autologous in vitro system by 51Cr release assay and EBV-determined nuclear antigen (EBV)-specific trypan blue exclusion method. The following results were obtained. 1. The EBV-transformed or EBV-infected lymphocytes were killed with high frequency, when they were incubated with autologous lymphocytes in the presence of EBV-positive autologous serum. Exposure to lymphocytes alone or to EBV-positive serum alone was not effective. 2. The cytotoxic reaction was directed against cells positive for EBV-induced membrane antigen complex (MA) but not against MA-negative transformed cells. 3. These data indicated that the present cytotoxic reaction represents antibody-dependent cellular cytotoxicity (ADCC). 4. Such ADCC, however, does not seem to function effectively in patients with systemic lupus erythematosus. (SLE). 5. A very small amount of interferon (5 IU/ml) was found to enhance ADCC activity. Interferon alone, however, was not cytotoxic enough, even though a much larger dose was given. Neither lymphocyte-interferon nor antibody-interferon mixture was effective. 6. Thus, the cooperation of lymphocytes, EBV antibodies and interferon is considered to be a major role in the protection against EBV-induced oncogenesis in seropositive healthy individuals.

Adult↗
PubMed1980

Immunologic cytotoxicity against autologous human lymphocytes transformed or infected by Epstein-Bar virus: role of antibody-dependent cellular cytotoxicity in health individuals.

Immunologic cytotoxicity against lymphocytes transformed or infected by Epstein-Barr virus (EBV) was mainly studied in an autologous in vitro system by 51Cr release assay and EBV-determined nuclear antigen (EBNA)-specific trypan blue exclusion method. When the cells of newly established EBV-transformed or spontaneously transformed lines were incubated with unfractionated autologous healthy donor lymphocytes or T-cell-depleted lymphocytes in the presence of EBV-positive autologous or allogeneic serum, the transformed cells were killed with high frequency. Exposure to lymphocytes alone or to EBV-positive serum alone was not effective. The cytotoxic reaction was directed against cells positive for EBV-induced membrane antigens (MA) but not against MA-negative transformed cells. A very small fraction (1 of 200) of healthy donor lymp]hocytes exposed to EBV converted into EBNA-positive and MA-positive cells, and these were also killed by the remaining autologous lymphocytes in the presence of EBV-positive serum. These results indicated that the present cytotoxic reaction represents antibody-dependent cellular cytotoxicity (ADCC), and this particular mechanism probably plays an important role in the immunologic surveillance in the protection against EBV-induced oncogenesis in seropositive individuals. Such ADCC, however, does not seem to function effectively in patients with systemic lupus erythematosus.

Antibodies, Viral↗
PubMed1978

The simultaneous observations of immunofluorescence and cellular morphology in viral infections: a new procedure.

A simple method for comparative observations of immunofluorescence and cellular morphology has been developed in the investigation of Epstein-Barr virus (EBV) infection and oncogenesis. When cells were stained for immunofluorescence of EBV-determined nuclear antigen, early antigens, or the viral capsid antigen, followed by treatment with hematoxylin, viral marker expression and cellular morphology could be simultaneously observed in individual cells by simply changing ultraviolet illumination to visible light. In our double-staining method, hematoxylin was not counteractive to specific immunofluorescence, and pretreatment of cells with antibodies did not affect hematoxylin staining. This method may possibly be more widely applied in virology and other fields.

Fluorescent Antibody Technique↗
PubMed1978

Abortive growth of human lymphocytes carrying a dormant Epstein-Barr viral genome.

When P3HR-1 lymphoblastoid cells expressing Epstein-Barr virus (EBV)-related antigens at very low frequency were cocultivated with human umbilical cord blood lymphocytes and the cell-free mixed culture fluid was applied to fresh cord lymphocytes, cells morphologically distinct from normal lymphocytes became evident after one to two weeks' exposure. The abnormal cells became abundant after one month and were easily identified by B-cell markers and a variety of morphologic abnormalities. Such abnormal B-lymphocytes appeared to be negative for EBV-determined nuclear antigen (EBNA), but when the immunofluorescence-negative cells were exposed to pokeweed mitogen and 5-iododeoxyuridine, a striking EBNA induction occurred. The growth of these abnormal cells was limited and they could be maintained for no more than three months. The implications of these findings are discussed in relation to the biological activity of EBV.

B-Lymphocytes↗
PubMed1978

Interaction between Epstein-Barr virus and type-C virus in human cells.

The interaction between EBV and type-C viruses was studied in our FVNC experimental system, in which EBV and type-C viral genomes are contained in each cell. The data indicate that the human lymphoid FVNC cells are sensitive to both EBV and type-C virus exposure, showing high frequencies of induction of both repressed viral genomes. The two different viral genomes may be associated with different chromosomes in individual cells.

Antigens, Viral↗
PubMed1978

Antibody-dependent autologous lymphocyte cytotoxicity against cells freshly transformed by Epstein-Barr virus.

Cytotoxicity against lymphocytes freshly transformed by EBV was studied in an autologous system by trypan blue exclusion of EBNA-positive cells and 51Cr-release assay. When EBV-tranformed lymphocytes were incubated with EBV-positive serum and autologous unfractionated lymphocytes or K-cells from sero-positive healthy donors, the transformed cells were significantly damaged. The cytotoxicity against newly produced EBNA-positive lymphocytes was also remarkable when sero-positive healthy donor lymphocytes were exposed to EBV, immediately followed by incubation with positive serum. In contrast, EBV-transformed cells incubated with autologous lymphocytes or T-cells alone were not significantly affected. EBV-positive serum alone was also not cytotoxic, regardless of inactivation. These results strongly suggest that antibody-dependent cellular cytotoxicity (ADCC) plays an important role in immunological defence against EBV oncogenesis in healthy humans. However, ADCC was not seen when immunosuppressed patients were examined.

Antibodies, Viral↗
PubMed1976

Growth in semisolid agar medium of human cord leukocytes freshly transformed by Epstein-Barr virus.

The semisolid agar method for the selective growth of transformed cells was applied to investigations of Epstein-Barr virus (EBV) transformation. When 1 X 10(5) HUMAn umbilical-cord blood leukocytes were seeded in agar medium immediately after EBV exposure, about 100 colonies developed in each dish. The occurrence of colonies correlated well with dilutions of EBV inoculum. These colonies were composed of lymphoblasts, were positive for EBV-determined nuclear antigen immunofluorescence, and consistently resulted in the establishment of cell lines. In cord leukocyte cultures exposed to EBV, cells capable of growing in semisolid agar medium appeared early and increased rapidly, though the total numbers of leukocytes and control cultures decreased during the first several days.

Cell Line↗