1/106. Acute leukemia with the phenotype of a natural killer/T cell bipotential precursor.An acute leukemia with an unusual immunophenotype developed in a 17-year-old girl. At the initial presentation, extramedullary involvement was not evident, but with advancing disease, massive splenomegaly and an osteolytic rib tumor developed. The disease was aggressive and refractory to intensive chemotherapeutic regimens for myeloid and lymphoid malignancies, and the patient died 3 months after the initial presentation. The leukemic cells were of irregular shape and variable size; they had deeply indented or bi-lobed nuclei and relatively fine, azurophilic granules in their cytoplasm. They were positive for acid phosphatase and beta-glucuronidase in granular staining, but they were negative for myeloperoxidase. The leukemic cells had a unique immunophenotype: it was positive for T-cell antigens (CD1a, CD2, cytoplasmic CD3, CD4), myeloid antigens (CD13 and CD33), NK-cell antigen (CD56), CD19 and CD30. dna analysis revealed no gene rearrangement in the T-cell receptor beta, gamma and delta, or immunoglobulin heavy chain genes. The leukemic cells of our patient are thought to have arisen from the transformation of a putative precursor cell common to both the T- and NK-cell lineage in the bone marrow. The current literature on precursor NK-cell malignancy is reviewed, and its clinicopathological feature is discussed.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/106. Derivation of a new hematopoietic cell line with endothelial features from a patient with transformed myeloproliferative syndrome: a case report.BACKGROUND: During embryonal development primitive hematopoiesis can be observed first in the yolk sac, in which both hematopoietic and endothelial cells are derived from a common precursor, the hemangioblast. Whether cells with this dual differentiation potential persist during postnatal life is unknown. methods: A cell line was derived from a patient with secondary acute leukemia. Because of its ability to grow in soft agar and in SCID mice, this cell line was analyzed for expression of differentiation antigens by fluorescence-activated cell sorter analysis, immunocytochemistry, fluorescent in situ hybridization (FISH) analysis with simultaneous cell surface staining, and polymerase chain reaction (PCR). RESULTS: A new cell line was established from a patient with essential thrombocytosis that transformed into acute leukemia. The patient's initial clinical presentation included skin and lymph node infiltrations that were taken for an angiosarcoma due to positivity for CD34, CD31, and von willebrand factor on immunohistology. In addition to hematopoietic markers, leukemic cells expressed endothelial antigens such as CD62E, CD105, and bound ulex europaeus lectin-1. Immunocytochemistry revealed positive staining for vascular endothelial growth factor receptor type 2 (KDR), Tie-2/Tek, the angiopoietin receptor, and vascular endothelial cadherin. These results were confirmed by PCR analysis. Simultaneous staining for CD62E and FISH analysis showed that cells with endothelial characteristics belonged to the leukemia. FISH analysis of histologic sections of the lymph node infiltration confirmed this manifestation as part of the leukemic process. The derived cell line, UKE-1, forms colonies in soft agar and is tumorigenic in SCID mice. CONCLUSIONS: This new cell line, UKE-1, appears to combine hematopoietic and endothelial features, indicating the close ontogenic relation of both lineages.- - - - - - - - - - ranking = 0.66666666666667keywords = antigen (Clic here for more details about this article) |
3/106. Coexistence of two distinct cell populations (CD56( )TcRgammadelta( ) and CD56( )TcRgammadelta(-)) in a case of aggressive CD56( ) lymphoma/leukemia.BACKGROUND AND OBJECTIVE: Large granular lymphocytes derive from two major lineages: one expressing the CD3 surface antigen (t-lymphocytes), and the other lacking this marker (NK-cells). Although developmental overlaps between natural killer cells and T-cells have been described, malignancies derived from these two cell types are considered as distinct lymphoid disorders. DESIGN AND methods: We report the case of a 30-year old man affected by a lymphoma/leukemia syndrome presenting with hepatosplenic lymphoma which rapidly transformed into aggressive NK-leukemia. Extensive flow cytometry studies and molecular analysis were repeated during the course of the disease, and showed an unexpected changing pattern. RESULTS: At diagnosis, flow cytometry analysis showed the co-existence of two cell populations, one CD56( ), CD3( ), TcRgd( ), and the other CD56( ), CD3(-) and TcRgd(-). Molecular analysis showed that the TcR genes had the same clonally rearranged pattern involving b, g and d genes in both populations. At disease relapse and during the terminal refractory phase, only CD3(-) cells were present. INTERPRETATION AND CONCLUSIONS: This is an unusual case of CD56( ) aggressive lymphoma/leukemia characterized by the clonal expansion of two phenotypically different cell populations, variably balanced during the course of the disease. The presence of the same TcR genomic rearrangement suggests the origin from a common progenitor able to differentiate along both T- and NK-pathways.- - - - - - - - - - ranking = 0.33333333333333keywords = antigen (Clic here for more details about this article) |
4/106. Massive immune haemolysis after allogeneic peripheral blood stem cell transplantation with minor ABO incompatibility.Immune haemolysis as a result of minor ABO incompatibility is an underappreciated complication of haematopoietic transplantation. The increased lymphoid content of peripheral blood stem cell (PBSC) transplants may increase the incidence and severity of this event. We observed massive immune haemolysis in 3 out of 10 consecutive patients undergoing HLA-identical, related-donor PBSC transplants with minor ABO incompatibility. Non-ablative conditioning had been given in 9 of these 10 cases, including two with haemolysis. Cyclosporin alone was used as prophylaxis against graft-vs.-host disease (GVHD). Catastrophic haemolysis of 78% of the circulating red cell mass led to anoxic death in the first case seen, but severe consequences were avoided by early, vigorous donor-compatible red cell transfusions in the subsequent two cases. Haemolysis began 7-11 d after PBSC infusion and all patients with haemolysis had a positive direct antiglobulin test (DAT), with eluate reactivity against the relevant recipient antigen. However, neither the intensity of the DAT, the donor isohaemagglutinin titre, nor other factors could reliably be used to predict the occurrence of haemolysis. Our data indicate that haemolysis may be frequent and severe after transplantation of minor ABO-incompatible PBSCs when utilizing cyclosporin alone to prevent GVHD. Meticulous clinical monitoring and early, vigorous donor-compatible red cell transfusions should be practiced in all instances.- - - - - - - - - - ranking = 0.33333333333333keywords = antigen (Clic here for more details about this article) |
5/106. Human herpesvirus 6 limbic encephalitis after stem cell transplantation.central nervous system complications are common in stem cell transplant recipients, but selective involvement of the medial temporal area is unusual. The 5 patients reported here presented after stem cell transplantation with increased hippocampal T2 signal on magnetic resonance imaging and increased hippocampal glucose uptake on [F-18]fluorodeoxyglucose-positron emission tomography (FDG-PET) associated with short-term memory loss, insomnia, and temporal lobe electrographic seizure activity. The initial scalp electroencephalograms (EEGs) failed to detect seizure activity in these patients, although the memory dysfunction along with the magnetic resonance imaging and FDG-PET findings suggested subcortical seizure activity. However, extended EEG monitoring revealed repetitive temporal lobe electrographic seizure activity. Follow-up MRIs in 2 patients and postmortem findings on 1 patient suggested that hippocampal sclerosis had developed following the clinical syndrome. cerebrospinal fluid studies revealed the presence of human herpesvirus 6, variant B, dna in all of 3 patients who had lumbar punctures. Immunohistochemical staining for the P41 and P101 human herpesvirus 6 protein antigens showed numerous immunoreactive astrocytes and neurons in the hippocampus of 1 of the patients who died from other causes. Because of its subtle clinical presentation, this syndrome may be underrecognized, but can be diagnosed with appropriate magnetic resonance imaging techniques, EEG monitoring, and cerebrospinal fluid viral studies.- - - - - - - - - - ranking = 0.33333333333333keywords = antigen (Clic here for more details about this article) |
6/106. Human acute stem cell leukemia with multilineage differentiation potential via cascade activation of growth factor receptors.The morphologic, immunophenotypic, genotypic, genomic, and functional features of an undifferentiated acute leukemia with stem cell features are reported. At light and electron microscopy, the leukemic population was represented by primitive progenitor cells with no evidence of differentiation. The blasts were CD34( ), AC133( ), CD71(-), HLA-DR(-), CD38(-/dim ), CD90( ), CD117(dim ), flt3( ); did not express B, T, or myeloid-associated antigens; and showed a germline configuration of the immunoglobulin and T-cell receptor. Genomic profiling documented the expression of early stem cell and myeloid-associated genes. Receptors for early-acting hemopoietic growth factors (HGFs) were detected, while receptors for unilineage HGF were not expressed. Incubation with the flt3 or Kit ligand induced the expression of unilineage HGF receptors, allowing these cells to respond to their respective ligands. growth without differentiation was sustained only in the presence of early-acting HGF, namely flt3 ligand, while early and unilineage HGF gave rise to all types of hemopoietic colonies.- - - - - - - - - - ranking = 0.33333333333333keywords = antigen (Clic here for more details about this article) |
7/106. Induction of graft-versus-host disease and a graft-versus-leukemia effect using ubenimex in a patient with infantile leukemia relapsing after an unrelated cord blood transplant.A 20-month-old boy with infantile leukemia was treated with total body irradiation, etoposide, cyclophosphamide and unrelated cord blood transplantation with a one-antigen mismatch. He relapsed on day 100 and achieved remission after ubenimex administration, and also developed chronic graft-versus-host disease of the skin. He remained in remission for 22 months with repeated courses of ubenimex. Ubenimex may be an alternative to donor lymphocyte transfusion and may be useful for the treatment of a patient who has relapsed after cord blood transplantation.- - - - - - - - - - ranking = 0.33333333333333keywords = antigen (Clic here for more details about this article) |
8/106. nephrotic syndrome with crescent formation and massive IgA deposition following allogeneic bone marrow transplantation for natural killer cell leukemia/lymphoma.We describe herein a case of nephrotic syndrome (NS) following allogeneic bone marrow transplantation (allo-BMT) for natural killer cell leukemia/lymphoma. Histologic studies defined the diagnosis as crescentic glomerulonephritis with massive immunoglobulin a (IgA) deposition, which has never been reported in NS cases following allo-BMT. Most of the massive infiltrated cells in the interstice were CD3( )CD4(-)CD8( ) T cells derived from the donor. We observed mesangial deposition of haemophilus parainfluenza outer membrane (OMHP) antigen and decreased glycosylation of the IgA1 hinge in the recipient's samples is consistent with the recently reported pathogenesis of IgA nephropathy. Further, the titer of IgA antibody against the donor serum was as high as other IgA nephropathy cases. These findings suggest that NS and crescentic glomerulonephritis in this case occurred as one of the forms of chronic graft-versus-host disease (GVHD), and that IgA deposition was associated with H parainfluenza and decreased glycosylation of the IgA1 hinge.- - - - - - - - - - ranking = 0.33333333333333keywords = antigen (Clic here for more details about this article) |
9/106. hematopoiesis-restricted minor histocompatibility antigens HA-1- or HA-2-specific T cells can induce complete remissions of relapsed leukemia.Donor lymphocyte infusion (DLI) into patients with a relapse of their leukemia or multiple myeloma after allogeneic stem cell transplantation (alloSCT) has been shown to be a successful treatment approach. The hematopoiesis-restricted minor histocompatibility antigens (mHAgs) HA-1 or HA-2 expressed on malignant cells of the recipient may serve as target antigens for alloreactive donor T cells. Recently we treated three mHAg HA-1- and/or HA-2-positive patients with a relapse of their disease after alloSCT with DLI from their mHAg HA-1- and/or HA-2-negative donors. Using HLA-A2HA-1 and HA-2 peptide tetrameric complexes we showed the emergence of HA-1- and HA-2-specific CD8( ) T cells in the blood of the recipients 5-7 weeks after DLI. The appearance of these tetramer-positive cells was followed immediately by a complete remission of the disease and restoration of 100% donor chimerism in each of the patients. Furthermore, cloned tetramer-positive T cells isolated during the clinical response specifically recognized HA-1 and HA-2 expressing malignant progenitor cells of the recipient and inhibited the growth of leukemic precursor cells in vitro. Thus, HA-1- and HA-2-specific cytotoxic T lymphocytes emerging in the blood of patients after DLI demonstrate graft-versus-leukemia or myeloma reactivity resulting in a durable remission. This finding implies that in vitro generated HA-1- and HA-2-specific cytotoxic T lymphocytes could be used as adoptive immunotherapy to treat hematological malignancies relapsing after alloSCT.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
10/106. wilms tumor gene peptide-based immunotherapy for patients with overt leukemia from myelodysplastic syndrome (MDS) or MDS with myelofibrosis.The wilms tumor gene, WT1, is overexpressed not only in leukemias and myelodysplastic syndrome (MDS) but also in various types of solid tumors, including lung and breast cancer, and the WT1 protein is a tumor antigen for these malignancies. In clinical trials of WT1 peptide-based cancer immunotherapy, patients with overt leukemia from MDS or MDS with myelofibrosis were injected intradermally with 0.3 mg of an HLA-A*2402-restricted, 9-mer WT1 peptide emulsified with Montanide ISA51 adjuvant. Only a single dose of WT1 vaccination resulted in an increase in WT1-specific cytotoxic t-lymphocytes, which was followed by a rapid reduction in leukemic blast cells. Severe leukopenia and local erythema at the injection sites of WT1 peptide were observed as adverse effects. These results have provided us with the first clinical evidence suggesting that WT1 peptide-based immunotherapy is an attractive treatment for patients with leukemias or MDS.- - - - - - - - - - ranking = 0.33333333333333keywords = antigen (Clic here for more details about this article) |
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