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)

A limiting dilution microculture system, supplemented with a source of interleukin-2 (IL-2), was employed to evaluate the frequency of Moloney-murine leukaemia/sarcoma virus (M-MuLV/M-MSV)-specific cytotoxic T-lymphocyte precursors (CTL-p) which also exhibited NK-like activity. Spleen cells, obtained from M-MuLV/M-MSV regressor mice, were restimulated in bulk secondary mixed leucocyte-tumour cell cultures (MLTC), and subsequently plated in a culture medium supplemented with two different supernatants (SN) produced following PMA-stimulation of the same EL-4 thymoma cell line. SN 20, obtained from the cell line maintained in vitro, contained IL-2 and only negligible amounts (less than 3 U/ml) of interferon (IFN), while SN 19, obtained after passage of the ascitic form of EL-4 thymoma in syngeneic mice, contained both IL-2 and IFN in high titres. The frequency of CTL-p specific for MBL-2 lymphoma cells was high and comparable in cultures supplemented with both SN (1/2 X 84 cells and 1/2 X 40 cells, respectively), while the frequency of CTL-p directed against NK-susceptible YAC-1 target cells was low in SN 20 (1/90 cells) and high in SN 19 (1/5 X 40 cells). An analysis of individual microcultures established at low cell dose (1 cell/well) indicated that specific and NK-like activity could be ascribed to the same precursor cells. Furthermore, using different long-term CTL clones, we observed that, after passage in SN 20, double-reactive clones gradually lose the capacity to lyse NK-susceptible targets, while most of MBL-2 specific clones acquired NK-like activity following a few passages in SN 19. Therefore, the induction of NK-like activity is reversible and may be modulated by soluble factors present in supernatant in which CTL clones are maintained. Double-reactive clones were unable to lyse NK-resistant allogeneic tumour cells or normal syngeneic blast cells. A few clones cross-reacting with H-2d alloantigens also exhibited NK-like activity when maintained in SN 19. The different pattern of CTL clone activity was associated with a morphological change in the clones themselves: the acquisition of double activity was accompanied by an increase in cell size and the appearance of numerous cytoplasmic granules. All CTL clones were phenotypically Thy-1+ and Lyt-2+ on indirect immunofluorescence and complement-dependent cytotoxicity investigation.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Reversibility of lymphokine-induced NK-like activity in virus-specific cytotoxic T-lymphocyte clones. 257 29

A new B-lymphoma cell line (DEAU-cell line) was established from a diffuse large-cell lymphoma (centroblastic type) and was successfully grafted in athymic nude mice. Monoclonal antibodies (MoAbs) were generated using splenocytes of DEAU-tumor bearing mice. Before the fusion experiments, cellular immunity of the mice bearing growing DEAU tumors was restored by injection of spleen cells from conventional Balb/C mice. Spleen cells from conventional Balb/C mice immunized with DEAU-cell line were also used for the generation of MoAbs. Four MoAbs (DBB.42 and DBA.44 from normal Balb/C mice, and DNA.7 and DND.53 from athymic nude mice) were investigated because they identified B-cell-associated antigens not destroyed by fixatives. DBB.42 recognized a pan-B cell-associated antigen (molecular weight (mol wt) = 45 Kd). DBA.44 detected a B-cell antigen (mol wt not determined) expressed on a subpopulation of B lymphocytes in the mantle zone of lymphoid follicles. DNA.7 also defined a B-cell antigen (43 Kd) mainly expressed on germinal center cells. Similarly, DND.53 recognized a B-cell antigen (two bands of mol wt 20 Kd and 35 Kd, respectively) mainly expressed on germinal center cells and mantle zone lymphocytes and interdigitating reticulum cells in the paracortical area. Major differences were found in the reactivities of these MoAbs on malignant lymphomas. DBB.42 was positive with almost all B-cell lymphomas and some T-cell lymphomas. Within the group of low-grade B-cell lymphomas, DBA.44 reacted principally with hairy-cell leukemia. DNA.7 reacted mainly with high-grade B-cell lymphomas with a weak positivity in low-grade B-cell lymphomas. DND.53 reacted with all but one B-cell lymphoma, cells of histiocytosis X, and Reed-Sternberg cells. These findings indicate that new MoAbs can be generated by using spleen cells from athymic mice bearing human tumors as well as by new lymphoid cell lines. The MoAbs so generated, as in the present study, are deemed potentially useful for the recognition of B-cell lymphomas in routine diagnostic histopathology. In addition, DND.53 could be of value for the diagnosis of histiocytosis X and the detection of Reed-Sternberg cells in Hodgkin's disease.
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PMID:Production of anti-B monoclonal antibodies (DBB.42, DBA.44, DNA.7, and DND.53) reactive on paraffin-embedded tissues with a new B-lymphoma cell line grafted into athymic nude mice. 267 17

Rapid kinetic techniques were used to study the transport and salvage of uridine and other nucleosides in mouse spleen cells. Spleen cells express two nucleoside transport systems: (1) the non-concentrative, symmetrical, Na+-independent transporter with broad substrate specificity, which has been found in all mammalian cells and is sensitive to inhibition by dipyridamole and nitrobenzylthioinosine; and (2) a Na+-dependent nucleoside transport, which is specific for uridine and purine nucleosides and resistant to inhibition by dipyridamole and nitrobenzylthioinosine. The kinetic properties of the two transporters were determined by measuring uridine influx in ATP-depleted cells and dipyridamole-treated cells, respectively. The Michaelis-Menten constants for Na+-independent and -dependent transport were about 40 and 200 microM, respectively, but the first-order rate constants were about the same for both transport systems. Nitrobenzylthioinosine-sensitivity of the facilitated nucleoside transporter correlated with the presence of about 10,000 high-affinity (Kd = 0.6 nM) nitrobenzylthioinosine-binding sites per cell. The turnover number of the nitrobenzylthioinosine-sensitive nucleoside transporter was comparable to that of mouse P388 leukemia cells. The activation energy of this transporter was 20 kcal/mol. Entry of uridine via either of the transport routes was rapidly followed by its phosphorylation and conversion to UTP. The Michaelis-Menten constant for the in situ phosphorylation of uridine was about 50 microM and the first-order rate constants for phosphorylation and transport were about the same. The spleen cells also efficiently salvaged adenosine, adenine, and hypoxanthine, but not thymidine.
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PMID:Na+-dependent and -independent transport of uridine and its phosphorylation in mouse spleen cells. 273 Sep 9

The hematopoietic disregulation in adult mice induced by the malignant histiocytosis sarcoma virus (MHSV) and the Harvey murine sarcoma virus (Ha-MuSV), which both possess c-Ha-ras-related oncogenic sequences, was investigated. Spleen focus formation induced by MHSV and Ha-MuSV was not restricted by the Fv-2 resistance locus in congenic DDD and C57BL/6 mice, unlike leukemogenesis induced by Friend virus, Rauscher virus, and the myeloproliferative sarcoma virus (MPSV). C57BL/6 mice were much more resistant to MHSV and Ha-MuSV-induced spleen focus formation than DDD mice regardless of their Fv-2 state. Infection of DDD mice with MHSV caused a systemic histiocytic neoplasia, best described as murine malignant histiocytosis. Transformed histiocytic cells proliferated excessively in the bone marrow, spleen, and lymph nodes and, in the final stages of the disease, in all major parenchymal organs. The Ha-MuSV caused a strikingly different benign histiocytic tumor in DDD mice and, unlike MHSV, did not induce a rapid, progressive splenomegaly in C57BL/6 mice. Infection of DDD mice with MHSV induced a rapid and synchronized depletion of early and late erythroid precursor cell pools. In MHSV-infected C57BL/6 mice comparable changes were observed with dissimilar kinetics. Macrophage colony-forming cells of MHSV-infected mice were increased in number and proliferated independently of stimulating growth factors. The disease induced by MHSV in mice can thus serve as a model for malignant histiocytosis in humans.
Leukemia 1987 Jan
PMID:Murine retrovirus-induced malignant histiocytosis, an experimental model for the disease in humans. 282 12

Previous studies in our laboratory and others have been consistent with the hypothesis that the envelope (env) gene of the spleen focus-forming virus (SFFV) is the only gene essential for the induction of acute erythroleukemia. However, no studies have been carried out with the SFFV env gene in the complete absence of other SFFV sequences. To accomplish this goal, we isolated the sequences that encode the envelope glycoprotein, gp52, of SFFVA and expressed them in a Moloney murine leukemia virus-based double-expression vector containing the neomycin resistance gene. The method used to produce retrovirus stocks in tissue culture cells affected the expression of the gp52 gene in the vector and the subsequent pathogenicity of the vector in mice. Highly pathogenic virus stocks were obtained by cotransfection of vector and helper virus DNAs into fibroblasts, followed by virus replication and spread through the cell population. Mice infected with this stock developed a rapid erythroid disease that was indistinguishable from that induced by the entire SFFV genome, and the virus stock transformed erythroid cells in vitro. Spleen cells from the diseased mice expressed the SFFV env gene product but not the SFFV gag gene product. As expected, mice given the virus containing the SFFV env gene in the reverse orientation did not express the SFFV env gene product or develop erythroleukemia. This study, therefore, demonstrated (i) that double-expression retroviral vectors can be used under specific conditions to produce viruses expressing high levels of a particular gene and (ii) that incorporation of the SFFV env gene into such a vector in the absence of other SFFV sequences results in a retrovirus which is as pathogenic as the original SFFV.
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PMID:The spleen focus-forming virus (SFFV) envelope gene, when introduced into mice in the absence of other SFFV genes, induces acute erythroleukemia. 283 16

Mice infected with LP-BM5 murine leukemia viruses (MuLV) develop a syndrome with many features in common with AIDS including lymphadenopathy and profound immunodeficiency associated with enhanced susceptibility to infection and terminal B cell lymphomas. To evaluate cellular defects that may predispose infected mice to these sequelae, we studied the regulation of IFN gene expression. Spleen cells from mice infected with LP-BM5 MuLV expressed high levels of IFN-gamma mRNA by 1 wk post-inoculation and throughout the course of disease. By comparison, transcripts of IFN-alpha/beta genes were not detected in spleen cells at any time after infection. In uninfected mice, expression of IFN-alpha/beta genes is induced rapidly after infection with New-castle disease virus, but mice inoculated with LP-BM5 MuLV were unable to induce these genes by 4 wk after retroviral infection. Inhibition of IFN-alpha/beta induction due to LP-BM5 MuLV infection also occurred in nude mice, indicating this effect was not mediated by activated T cells. Furthermore, low levels of IFN-gamma transcripts were detected in spleens of nude infected mice, suggesting that cells other than T cells can express this gene. These results suggest that the normal contributions of IFN to control of microbial spread, immune surveillance, and lymphoid interactions are disrupted by infection with LP-BM5 MuLV.
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PMID:Abnormal regulation of IFN-alpha, -beta, and -gamma expression in MAIDS, a murine retrovirus-induced immunodeficiency syndrome. 284 90

Spleen cells from acutely diabetic (AD) and non-diabetic but diabetes prone (DP) BB/Wor rats lysed insulinoma target cells to a significantly greater degree than did diabetes resistant (DR) cells as determined using a 51Cr release cytotoxicity assay. There were no differences between the AD and DP groups. Lysis was not target cell specific, since somatostatin secreting RIN 14B cells, Wistar Furth leukemia cells designated LW12, PC12 cells and NK sensitive YAC-1 cells were also lysed. Lysis of all target cells was significantly reduced by pretreatment of the effector lymphocytes with antiserum to NK cells (anti-asialo GM1) and complement suggesting that NK cells mediated destruction of these cells. These data demonstrate a generalized increase in non-specific NK cell activity in BB/Wor rats. Since NK cells have been shown to mediate antibody dependent cell mediated cytotoxicity (ADCC), splenic lymphoid cells from AD rats were tested for their ability to lyse insulinoma target cells in the presence of diabetic rat sera which were demonstrated to contain islet cell surface antibodies. Three different ADCC protocols were tested but in each case the addition of serum dilutions from AD rats reduced the lysis of insulinoma cells by AD spleen cells in a dose dependent manner. This inhibition was also demonstrated when sera and effector cells from control rats were used. As a positive control, DR spleen cells were incubated with 51Cr labelled target cells that were untreated or pre-treated with anti-rat class 1 antibody (OX18). Pre-treatment of the target cells resulted in a marked increase in their subsequent lysis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:In vitro natural killer cell activity in the spontaneously diabetic BB/Wor rat: effects of serum on lysis of insulinoma cells. 285 69

Radiation-induced L8313 leukemia bearing mice (L8313 mice) had marked granulocytosis with splenomegaly. Hemopoietic stem cells and progenitors increased in the spleen but not in the bone marrow. Spleen conditioned-medium and serum from L8313 mice induced the formation of granulocyte-macrophage colonies (CFU-GM), erythroid bursts (BFU-E) and mixed colonies (CFU-Mix). Bone marrow conditioned medium did not show such activity. A cell line (STIL-3) was established from the spleen cells of L8313 mice. Surface marker analysis showed that the established cells were suppressor T cell. The cells produced IL-3 and GM-CSF in vitro, and induce essentially the same "leukemic" response in recipient mice. Inoculation of STIL-3 in diffusion chamber also induced leukemoid reaction, i.e. a marked granulocytosis with splenomegaly. Therefore, L8313 leukemia may be linked to an abnormality of growth and production of hemopoietic factors in hemopoietic regulatory cells.
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PMID:Physiopathological studies on granulocyte-macrophage colony stimulating factor and multi colony stimulating factor producing leukemia, L8313, induced by irradiation of C3H mice. 287 75

In our laboratory, we have developed a murine model to examine GVHD across minor histocompatibility antigens. In our model, GVHD is induced by injecting B10.D2 spleen cells into irradiated BALB/c recipients. Seven to 10 days after irradiation and injection of cells, there are significant changes in cell function in the recipient spleens. In the B10.D2----BALB/c (600 rad) model, recipient spleen cells are profoundly unresponsive to Con A and LPS stimulation but show increased B cell activity measured by Staphylococcus aureus protein A plaque-forming activity. Spleen cells from such GVH mice profoundly suppress the mitogenic responses of normal BALB/c or B10.D2 spleen cells to Con A and LPS. The degree of impairment of the mitogenic response and the ability to suppress normal cells is proportional to the dose of cells used to induce GVH reactions. Both the inability to respond to mitogens and the capacity to suppress are also related to the dose of irradiation given to the recipients. In addition, immunosuppression across minor histocompatibility antigens shows an unevenhandedness. If we inject parental B10.D2 or BALB/c cells into F1 recipients (P----F1), there is greater inhibition of mitogenic responses when B10.D2 parental cells are given than when BALB/c cells are given to the irradiated F1 recipients. These experiments show that significant immunosuppression occurs during GVH reactions across minor histocompatibility barriers. The degree of suppression varies according to the dose of cells used to induce GVH, the dose of irradiation to the recipient and the "strength" of the GVH recognition system. Such experiments provide models for GVH disease seen in humans who receive treatment for leukemia or other diseases that involves recipient irradiation and infusion of HLA-identical bone marrow.
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PMID:Graft-vs-host reactions (GVHR) across minor murine histocompatibility barriers. I. Impairment of mitogen responses and suppressor phenomena. 315 67

The genetic control of hapten-reactive helper T-cell activity involved in cytotoxic T-lymphocyte (CTL) responses and its implications for augmenting tumor-specific immunity were studied. C57BL/6N mice were immunized to trinitrophenyl (TNP) or N-iodoacetyl-N'-(5-sulfonic l-naphthyl)ethylenediamine (AED) hapten by inoculation of hapten-modified syngeneic spleen cells. Spleen cells from these hapten-immunized mice were tested for hapten-reactive helper T-cell activity for generation of CTL. TNP-primed spleen cells resulted in only marginal help for the generation of anti-TNP-modified syngeneic spleen cell (TNP-self) CTL response when cocultured with normal C57BL/6N spleen cells (responding cells) in the presence of TNP-self. In contrast, AED-primed spleen cells exhibited appreciable help for AED-induced CTL responses. Furthermore, AED-helper, but not TNP-helper, T-cell activity was demonstrated to augment the generation of antitumor (RBL-5 leukemia) CTL responses from normal syngeneic spleen cells when stimulated with the corresponding hapten-self plus RBL-5 tumor cells. These results indicate that the successful augmentation of syngeneic tumor immunity through T-T-cell interaction with the use of hapten-reactive helper T-cells can depend on selection of the appropriate haptenic reagent in an individual expressing a given major histocompatibility haplotype.
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PMID:Genetic control of hapten-reactive helper T-cell responses and its implications for the generation of augmented antitumor cytotoxic responses. 315 72


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