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11/64. antigens shared by malignant plasma cells and normal B cells may be involved in graft versus myeloma.

    Cytotoxic T cells play an important role in graft-versus-host-disease (GvHD) and graft-versus-leukaemia/myeloma, which may occur in patients treated with an allogeneic stem cell transplantation (ASCT). Here, we describe the selection of a myeloma reactive CD4 cytotoxic T cell-line (CTL) and two CD4 clones from this CTL. The CTL was generated from the blood from a patient with multiple myeloma (MM) with graft versus myeloma/GvHD, following an ASCT. The CTL was stimulated using irradiated peripheral blood mononuclear cells and EBV transformed B cells from the myeloma patient (EBVp), both of which were obtained prior to ASCT. Both the CTL and the two T cell clones specifically lysed EBVp and secreted IFN-gamma after coculture with EBVp and autologous myeloma tumour cells in a class II restricted fashion. These results show that myeloma tumour cells and autologous B cells present a common polymorphic peptide that functions as a target for graft derived cytotoxic T cells. Identification of these proteins will give insight into the relationship between graft versus myeloma (GvM) and GvHD and may provide immunotherapeutical targets in the treatment of MM. ( info)

12/64. Carrier detection in agammaglobulinemia by x chromosome inactivation analysis.

    Using a recently developed strategy to analyze patterns of x chromosome inactivation in cell populations, we found that two mothers and a sister were carriers in three atypical or sporadic cases of patients with agammaglobulinemia, two of whom were brothers. In this study, a phosphoglycerate kinase 1 (PGK1) gene probe was used to detect patterns of methylation of X-chromosome genes. A random pattern of X inactivation was observed in isolated peripheral blood granulocytes. In contrast, one of the two X chromosomes was preferentially active in the Epstein-Barr virus (EBV)-transformed peripheral B cells of the family members of these patients. The volume of the blood specimen could be significantly reduced using EBV-transformed B cell lines which contained multiple clones. The analysis described here can be used to distinguish between X-linked agammaglobulinemia (XLA) and other forms of a- or hypo-gammaglobulinemia as well as to detect the carrier state. ( info)

13/64. acquired immunodeficiency syndrome-associated T-cell lymphoma: evidence for human immunodeficiency virus type 1-associated T-cell transformation.

    The majority of lymphomas in the setting of acquired, iatrogenic, or congenital immunodeficiencies are B-cell lymphoproliferations. We describe a rare T-cell lymphoma in a fulminantly ill patient infected with human immunodeficiency virus type 1 (hiv-1). The T-cell nature of the process was defined genotypically (monoclonal T-cell receptor beta-chain [CT beta] rearrangement) and phenotypically (CD45RO , CD4 , CD5 , CD25 , CD8-, CD3- and negative for a variety of B-cell and monocyte markers). The CD4 , CD25 (interleukin-2 receptor [IL-2R]) phenotype with production of IL-2 and IL-2R rna is analogous to human T-lymphotropic virus type I (HTLV-I)-associated adult T-cell leukemia/lymphoma (ATLL); however, no HTLV-1 could be detected. Southern blot analysis did demonstrate monoclonally integrated hiv-1 within the tumor genome. Furthermore, the tumor cells were producing HIV p24 antigen as shown by immunohistochemistry. This is the first case of acquired immunodeficiency syndrome (AIDS)-associated non-Hodgkin's lymphoma in which hiv-1 infection may have played a central role in the lymphocyte transformation process. ( info)

14/64. Successful control of Epstein-Barr virus (EBV)-infected cells by allogeneic nonmyeloablative stem cell transplantation in a patient with the lethal form of chronic active EBV infection.

    Chronic active Epstein-Barr virus infection (CAEBV) is a heterogeneous EBV-related disorder, ranging from mild/moderate forms to rapidly lethal disorders. The lethal form of CAEBV is characterized by multiple organ failure, hemophagocytic syndrome, and development of lymphomas. Allogeneic stem cell transplantation is considered as the only potentially curative treatment for the lethal form of CAEBV, but it is not always desirable because of the high incidence of regimen-related toxicities. A 17-year-old female with CAEBV, who was refractory to conventional therapies and considered to be unable to receive a myeloablative regimen because of multiple organ dysfunction, underwent allogeneic nonmyeloablative stem cell transplantation (allo-NST) before developing a hematological malignancy. She has been well without any signs of CAEBV for 27 months after allo-NST, and we confirmed that specific cytotoxic T lymphocyte activity against EBV was reconstituted. This outcome suggests that allo-NST can control CAEBV by reconstituting the host immunity against EBV. ( info)

15/64. Relatively common mutations of the bloom syndrome gene in the Japanese population.

    bloom syndrome (BS) is a rare autosomal recessive genetic disorder characterized by lupus-like erythematous facial telangiectasia, sun sensitivity, infertility, stunted growth and a high predisposition to various types of cancer. Chromosomal abnormalities are hallmarks of this disorder, and high frequencies of sister chromatid exchanges and quadriradial configurations in lymphocytes and fibroblasts are diagnostic features. BLM is the causative gene for BS. We investigated the mutation in the BLM gene in 4 Japanese BS kindreds. Taken together with previously documented mutations, 2 kindreds were homozygous for 631delCAA and 2 were compound heterozygous for 631delCAA. The silent mutation of A1055C (Thr to Thr) was detected in control Japanese individuals. The 6-bp deletion/7-bp insertion at position 2,281, which most Askenazi Jewish BS patients carry, was not detected in 200 Japanese alleles. These results suggest that 631delCAA is a relatively common mutation among the Japanese BS patients. ( info)

16/64. Burkitt transformation of mantle cell lymphoma.

    The associated poor prognosis and potentially aggressive behavior of mantle cell lymphoma and its blastoid variants make differentiation from other non-Hodgkin B-cell lymphomas especially important. We present a case of mantle cell lymphoma with a marked leukemic component, which demonstrated both a typical nodular mantle cell pattern and burkitt lymphoma within a single lymph node removed at the time of splenectomy. The presence of CD5, CD10, and Bcl-1 co-expression by immunohistochemistry and detectable t(11;14) and cMYC gene rearrangement by FISH analyses in the Burkitt region support a transformation of mantle cell lymphoma over a concomitant malignancy. A limited number of mantle cell lymphomas demonstrating dual t(11;14) and chromosome 8q24 cMYC gene rearrangements have been previously reported in the literature. They demonstrate an extremely aggressive course with a very poor prognosis. Although the accelerated terminal phase of this patient's clinical course mirrors these previous published cases; none have described the combined morphologic and immunophenotypic features of burkitt lymphoma reported here. This case provides further support for the aggressive nature of these lymphomas and demonstrates the utility of flow cytometry, immunohistochemistry, and cytogenetic techniques in avoiding potential errors in their diagnosis, prognosis, and treatment. ( info)

17/64. Follicular lymphoid hyperplasia of the oral cavity representing progressive transformation of germinal center.

    Follicular lymphoid hyperplasia (FLH) of the oral cavity is a rare and poorly understood lymphoproliferative disorder. We present a case of FLH of the oral cavity presenting with progressive transformation of germinal center (PTGC). The patient was a 49-year-old Japanese woman presenting with a hard mass in the right cheek. The resected specimen contained numerous lymphoid follicles with active germinal centers and a portion of the lymphoid follicles exhibited PTGC. The PTGCs contained a few large lymphoid cells resembling lymphocytic and histiocytic reed-sternberg cells of nodular lymphocyte-predominant Hodgkin lymphoma. The PTGC was surrounded by groups of epithelioid cells. in situ hybridization studies demonstrated strong expression of Epstein-Barr virus (EBV)-encoded small rna in scattered large lymphoid cells in the PTGC. Although the etiology of FLH of the oral cavity remains unclear, the present case suggests that a subset of FLH of the oral cavity appears to be an EBV-associated lymphoproliferative disorder. ( info)

18/64. Establishment and characterization of a B-cell line derived from a patient with a myelodysplastic syndrome which expresses myelomonocytic and lymphoid markers.

    We describe a novel continuous B-cell line (PV-90) derived from a patient with myelodysplastic syndrome (MDS) and originating from spontaneous infection with the Epstein-Barr virus (EBV). The patient progressed to acute myeloblastic leukaemia (AML) 5 months after clinical onset of MDS. PV-90 is of clonal origin as indicated by the presence of immunoglobulin (Ig) gene rearrangements, monoclonal surface immunoglobulins, and a single dna restriction fragment corresponding to the EBV genomic termini. PV-90 cells also express a number of myelomonocytic markers, including alpha-naphthyl acetate esterase (ANAE), coagulation factor xiii, and CD68 antigen. Moreover, PV-90 cells constitutively express the c-fms proto-oncogene mRNA as the patient's blast cells did. Whereas a trisomy 11 ( 11) was found in the patient's bone marrow cells, PV-90 cells had a normal karyotype initially, but at 4 months showed two different and independent chromosomal abnormalities: 90, XX, -Y, -Y, t(9;16) (q11;p13), and 90, XX, -Y, -Y, t(17;18) (p13;q21), the latter possibly involving the p53 (17,p13) and bcl-2 (18, q21) proto-oncogenes. The early development of these chromosomal aberrations is consistent with a genetic instability of PV-90 cells. Expression of bi-lineage markers and genetic instability may suggest that PV-90 cells originated from transformation of a myelodysplastic progenitor cell capable of both myeloid and B-cell differentiation. The PV-90 cell line might be useful in a number of studies, including the possible role of c-fms in cell differentiation, pathogenetic mechanisms of human preleukaemia and lineage promiscuity in acute leukaemia. ( info)

19/64. Establishment and characterization of a bi-phenotypic leukemic cell line, NALM-19, from a patient with acute leukemia.

    Based on the immunophenotypic and genotypic findings, this acute leukemia cell line, designated NALM-19, is unique in that a partial expression of both B-cell and myeloid cell features are present in this single clonal leukemic cell population. It is noteworthy that two "normal" EB virus-transformed B cell lines, B239 and B240, (paired with NALM-19) were established from the same leukemic blood. ( info)

20/64. Two t(9;22) leukemia cell lines (NALM-24 and NALM-25) with bi-phenotypic characteristics and an EBV-positive B-cell non-leukemia cell line (B262) established from a patient with acute lymphoblastic leukemia.

    Based on the immunophenotypic, cytogenetic and genotypic findings, two unique leukemia cell lines, NALM-24 and NALM-25, and an EBV-transformed "normal" B-lymphoblastoid cell line (B262) from a patient with ALL were established and characterized. NALM-24 and NALM-25 are unique in that expression of both show B cell and myeloid cell features with the t(9;22) chromosome in single clonal leukemic cell populations. ( info)
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