Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

BALB/c mice were injected with an affinity-chromatography-purified placental transferrin receptor preparation. Spleen cells were fused with NS-1 myeloma cells. Sixteen hybrids producing monoclonal antibodies specific for the transferrin receptor and two hybrids specific for transferrin were identified by radioimmunoassay (RIA). Five hybrids were selected for cloning on the basis of antibody specificity and affinity. None of the antibodies inhibited the binding of transferrin to K562 cells. The binding of antibody ID9 to K562 cells was partially inhibited by transferrin or a polyclonal goat anti-transferrin receptor antiserum. Of the five antibodies, two (IIB6 and IIB2) reacted only with the purified receptor and solubilized cells and not with whole cells. The other three antibodies, when tested with normal human cells and leukaemia and tumour cell lines, showed identical reaction patterns. The antibodies precipitated a glycoprotein from K562 cells with an apparent molecular weight of 94,000, estimated from sodium dodecyl sulphate-polyacrylamide gel electrophoretograms run under reducing conditions, and a molecular weight of 188,000 when run under unreduced conditions. All antibodies have a high affinity with Ka values ranging from 1.44 X 10(9) to 3.56 X 10(10) (l/mol). The antigen precipitated by all five antibodies showed identical peptide maps after partial proteolytic digestion.
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PMID:Monoclonal antibodies to a purified human transferrin receptor. 609 40

C.B-20 mice were immunized with splenocytes or B leukemia cells (BCL1) from Ig H chain allotype congenic strains. Spleen cells from these immunized mice were rechallenged in vitro to generate H-2-restricted cytotoxic T cells that were specific for target antigens controlled by genes linked to the Ig H chain locus. The anti-Ig H cytotoxic T cells detected an antigen(s) expressed only on surface Ig+ cells. Thus, T cell lymphoblasts, eight BALB/c myeloma cell lines, and a T cell lymphoma were not lysed by the effector cells. In contrast, B cell lymphoblasts and the surface Ig+ BCL1 cells were sensitive to lysis. A surface Ig- hybridoma (which secretes the IgM from the BCL1 cells) generated by fusing BCL1 cells to X63 myeloma cells was not killed by the effector cells. These data indicate that cytotoxic T cells specific for antigenic determinants on either surface IgM+ or IgD+ or on a molecule that is coordinately expressed on IgM+ or IgD+ cells can be generated and that such cells might play a role in regulating the growth of normal B cells or surface Ig+ tumor cells in vivo.
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PMID:Cytotoxic T cells specific for antigens expressed on surface immunoglobulin-positive cells. 617 Jul 17

We have reported that immunization of H-2k mice with lymphoid cells from various allogeneic strains induced a population of cells that could eliminate first-passage spontaneous AKR leukemia from the spleens of immuno-suppressed AKR (H-2k) hosts. In the present study, we examined the nature of the cells responsible for this graft-vs-leukemia (GVL) reaction and compared them to cytolytic cells detected in vitro. Spleen cells from alloimmunized CBA/J (H-2k) mice were selectively depleted of various subpopulations by treatment with antibody and complement (C), then tested in vivo for GVL reactivity. Cell suspensions depleted of Thy-1.2+, Lyt-1+, or Lyt-2+ lymphocytes had no significant GVL reactivity, whereas suspensions depleted of NK-1.2+ cells retained GVL reactivity. The GVL-reactive cells persisted in H-2-compatible donor mice for up to 56 days. Lyt-1+2+ lymphocytes that were cytotoxic for cultured AKR leukemia cells in vitro could be detected in the spleens of alloimmunized H-2-compatible mice after expansion of the cells in T cell growth factor. Using quantitative limiting dilution cytotoxicity assays, we found that the frequency of leukemia-reactive cytotoxic lymphocytes (CL) in the spleen showed a direct correlation with the GVL efficacy of the cells in vivo. Alloimmunization was essential for induction of the GVL-reactive cell population. CL in alloimmunized mice consisted of heterogeneous cytotoxic specificities; i.e., some CL were leukemia-specific, others lysed only nonleukemic AKR target cells, and a third group mediated killing of both leukemic and nonleukemic target cells. The CL appeared to be H-2 restricted and specific for non-H-2 antigens shared by the AKR leukemia and the alloimmunizing cells.
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PMID:Characterization of alloimmunization-induced T lymphocytes reactive against AKR leukemia in vitro and correlation with graft-vs-leukemia activity in vivo. 619 24

The major histocompatibility complex of the rat (RTl) is composed of at least five subregions. They are RTl-A,B,C,D and E regions. RTl-A,E and RTl-B,D regions encode class I and class II alloantigens, respectively. The RTl-C region encodes antigens which are similar to class I alloantigens and they are the homologue of mouse Qa-Tla antigens. A monoclonal antibody (X81-5C9) was produced against a rat B-cell leukemia, KNL-14. The KNL-14 cells were injected to a congenic rat, WKA. 1A(ACI). Spleen cells taken from the congenic rat were hybridized with mouse myeloma cell line P3.X63.Ag8.653. The monoclonal antibody lysed over 80% of nylon wool (N. W) adherent cells of lymph nodes, 25-30% of unseparated lymph node cells and/or spleen cells, and approximately 15-20% of peripheral blood lymphocytes of WKAH strain of rats. Only a portion (30-40%) of N. W. adherent cells of the peripheral blood lymphocytes was killed. Bone marrow cells, thymus cells and N. W. nonadherent cells were not lysed by the antibody. Macrophages, fetus, thymus and kidney homogenates could absorb the reactivity, whereas RBC, epidermal cells, brain, liver, testis could not absorb the cytotoxicity. A survey for the strain distribution of the antigen disclosed positive strains such as WKAH, W/Hok, LEJ, WKA. 1J (LEJ), ALB, WKA. 1B (ALB), BUF, BN, LEW, F344, W. 1L (F344) and KYN rats. The negative strains were NIG-III, WF, WKA. 1U WF), SDJ, W. 1U (SDJ), TO, W. 1T(TO), ACI, WKA. 1A(ACI), BDIX, WKA. 1DV1 (BDIX) and PVG/c rats. Immunochemically, the antibody precipitated antigens that gave two major bands on the SDS-PAGE. The heavy chain has an apparent molecular weight of 30 KD, which shifted to 33 KD under reducing conditions. The light chain has an apparent molecular weight of 12 KD. From these data a monoclonal antibody X81-5C9 is considered to detect a rat MHC (RTl) gene product which is different from the classic class I or class II cell surface antigens. It may be one of RTl-C antigens expressed mainly on B-cells. The characteristic feature of rat RTl-C antigens were discussed in relation to mouse Qa-Tla antigens.
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PMID:[A new B-cell alloantigen of the rat]. 623 70

To specify the mechanism whereby inoculation of sarcoma viruses protects against leukemia development by leukoviruses, several experiments were performed using Friend virus complex (FVC) and MSV-F, a sarcoma virus pseudotype prepared in vitro with FVC as source of the helper component. The sarcomatous lesions induced by MSV-F were self-limited, irrespective of dose and route of inoculation and protected against the progressive, lethal erythroleukemia induced fy FVC. The sera of MSV-F primed mice had high FVC-neutralizing titers, Out of 3 properties titered in FVC, immunogenicity, XC-syncytium-forming activity and lethality, the frmer two were retained at high titers in MSV-F, while lethality was almost entirely lost: the dose-range between lethal immunizing dilutions was 2-3 logs broader for MSV-F than for FVC. It is postulated that the lethal, early erythroleukemia inducing component (Spleen Focus Forrming Virus) is rapidly lost from FVC upon in vitro propagation. The rescued MSV-F would carry a hightitered, immunogenic and Xc-syncytium forming component (Lymphatic Leukemia Virus), thus behaving as an immunogenic virus of limited pathogenicity.
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PMID:Immunity to Friend virus complex: analysis of protection with a sarcoma virus pseudotype. 625 97

The cytotoxic sensitivity of murine leukemia virus (MuLV)-infected and noninfected fibrosarcoma cells in syngeneic inbred WKA/Hok rats was compared by in vitro cell-mediated 51Cr release cytotoxicity assay. A highly significant increase in cytotoxic sensitivity of target cells was observe in MuLV-infected tumor cells as compared with noninfected cells when spleen cells from syngeneic tumor-bearing hosts (TBH) were used as a source of effector lymphocytes. The cytotoxicity of spleen cells against MuLV-infected tumor cells was specifically directed to the tumor-associated antigen (TAA), but not to the virus-associated antigen. However, there was no quantitative difference in the amount of TAA on the cell membranes between virus-infected and noninfected tumor cells as measured by a quantitative absorption test of anti-TAA serum. The cytotoxic activity of spleen cells from TBH against MuLV-infected tumor cells was abrogated by the treatment of anti-T-serum plus complement and significantly decreased after trypsin treatment. Spleen cells from normal rats given injections of immune sera from TBH acquired the cytotoxic activity against MuLV-infected tumor cells.
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PMID:Increased sensitivity of murine leukemia virus-infected tumor cells to lymphocyte-mediated cytotoxicity. 626 45

A clinical and laboratory evaluation of 28 patients with hairy cells leukemia is performed. Twenty-two had splenomegaly and all but one had a pancytopenia with 5 to 70% of hairy cells in blood. A tartrate-resistant acid phosphatase activity was positive in the hairy cells of 11 patients of 14 studied. In all patients a myelofibrosis and a leukemic infiltration were found in a bone-marrow biopsy of iliac crest. Hemodilution by splenomegaly, mild hemolysis and dyshematopoiesis were observed in 10 patients by a 51Cr or 59Fe isotopic exploration. In seven cases an immunological study of the hairy cells was performed, a high percentage of the leukemic cells of these 7 patients had polyclonal surface Ig but without resynthesis of monoclonal S Ig which is a feature usually associated with B lymphocytes. In the blood of these patients normal T and B lymphocytes were decreased. A splenectomy was done in 12 patients (43%) always for severe pancytopenia Splenectomy was not randomised. Spleen weights ranged from 1 085 to 3 600 g. In splenectomised patients the level of hemoglobin, segmented cells and thrombocytes was significantly higher after surgery. The survival rate is better in the splenectomised group (median survival 57 months) than in the non-splenectomised group (median survival 19 months). Infectious diseases were frequent in all patients but less after splenectomy. Fourteen patients died, 8 owing to pancytopenia.
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PMID:[Hairy cell leukemia. I.--Clinical, biological and evolutive study on twenty-eight cases (author's transl)]. 627 Jul 94

Spleen cells from mice immunized with Epstein-Barr virus-transformed lymphoblastoid cells (EB-LCL) were used to generate monoclonal antibodies to cell surface antigens associated with the EB virus-transformed state. Radioimmune and immunofluorescence binding assays identified two antibodies, MHM6 and AC2, which reacted consistently with all EB-LCL tested, with a subpopulation of cells in some but not all EB virus genome-positive Burkitt lymphoma lines, but with none of a range of EB virus genome-negative cell lines of lymphoma or leukaemia origin. While MHM6 appeared to bind an EB virus-related antigen, AC2 bound some other cell surface antigen which was also found on a small subpopulation of cells in lymphocyte cultures stimulated with phytohaemagglutinin or with pokeweed mitogen. MHM6 and AC2 recognized single polypeptides with apparent molecular weights of 45 kd and 80 kd respectively as shown by sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of 125I-labeled cell surface polypeptides immunoprecipitated with these antibodies. These polypeptides were induced on experimentally-infected B cells within 24 h of the expression of the EB virus nuclear antigen, EBNA, at a time known to coincide with the appearance of the lymphocyte-detected membrane antigen, LYDMA. However, saturating concentration of MHM6 and AC2 were unable to protect EB-LCL target cells from lysis by LYDMA-specific cytotoxic T cells in a chromium-release assay.
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PMID:Monoclonal antibodies to Epstein-Barr virus-induced, transformation-associated cell surface antigens: binding patterns and effect upon virus-specific T-cell cytotoxicity. 628 62

Spleen cells from a DBA/2 mouse immunized with RL male 1 tumor cells, a radiation induced BALB/c T-cell leukemia, were hybridized with the nonsecretor myeloma line NS.1. Four established hybrid cell lines continuously secreted antibodies that recognized a new alloantigenic specificity, tentatively called Ly-m22. This antigen is detectable on nearly 60% of lymph node cells, and 30% of spleen cells by direct cytotoxicity assay, but did not lyse significant number of cells of thymus and bone marrow. By absorption test, these lymphoid organs, i.e., lymph node, spleen, thymus, and bone marrow, were shown to express Ly-m22 determinant. The newly found antigen is expressed predominantly on T-cells. Analysis of BXD and SWXL recombinant inbred strains revealed close linkage between Ly-m22 and Ltw-4 loci on chromosome 1. The estimated recombination frequency is 0.027 +/- 0.081.
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PMID:Mouse alloantigen system Ly-m22 predominantly expressed on T lymphocytes and controlled by a gene linked to M1s region on chromosome 1. 633 54

Spleen cells collected from DBA/2 (H-2d) mice inoculated with the polycythemic variant of Friend-Leukemia Virus Complex (FLV-P) were tested for T-dependent immune functions, such as the in vitro generation of cytotoxic T lymphocytes (CTL) and of non-specific T suppressor lymphocytes (STL). CTL were generated against H-2b splenocytes, and STL were obtained following a 5-day lymphocyte culture without stimulator cells. A progressive and severe impairment of the generation of both CLT and STL was found from 2 weeks onward after infection, being almost totally abolished 3-4 weeks after virus challenge. Suppressor cells (SC) capable of inhibiting CTL generation was detected in FLV-P bearing mice. Suppressor activity was unaffected by anti-Thy 1.2 serum and complement but was removed following iron-magnet depletion or passage through nylon-wool column. Moreover complete recovery of the competence of CTL generation was attained when FLV-P infected splenocytes were passed through nylon-wool column. It is concluded that FLV-P infection depresses T-dependent cytotoxic and suppressor responses in mice, by the appearance of non-T adherent phagocytic cells, capable of impairing CTL generation in vitro.
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PMID:Impairment of in vitro generation of cytotoxic or T suppressor lymphocytes by Friend leukemia virus infection in mice. 645 95


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