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 histological stain described by Menzies in 1963 has been useful in detecting early evidence of erythroleukemia (Friend disease) in mouse hemopoietic tissues fixed in formaldehyde solution. With the use of this stain, one can distinguish erythroblastic leukemia cells from lymphoblastic leukemia cells.
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PMID:A histological stain for detecting Friend leukemic cells in fixed hemopoietic tissue. 6 94

The major viral phosphoproteins (p12) of the Rauscher murine leukemia virus (R-MuLV) and the simian sarcoma-associated virus (SSAV) bind in vitro to their homologous 70S and 35S viral RNAs. Using purified 32P-labeled RNA and 125I-labeled p12 protein, complexes that are stabilized by formaldehyde-cross-linking can be readily detected after velocity gradient centrifugation. The in vitro reconstructed ribonucleoprotein complexes are seen only with p12 proteins incubated with viral RNAs isolated from the same type C viruses; no such complexes form with heterologous protein-RNA mixtures. Homologous but not heterologous p12 molecules compete with radiolabeled p12 protein for the specific viral RNA binding sites. The competition assay permits the detection of 10 ng of viral p12 protein. The major internal protein of type C viruses (p30) does not bind to viral RNA using identical assay conditions. From the specific activities of the radiolabeled components and also by equilibrium sedimentation analysis, we estimate that fewer than 15 molecules of p12 protein bind to each molecule of viral RNA. Both the specificity and stoichiometry of the p12-RNA interactions suggest that these RNA tumor virus proteins have a regulatory role in cells.
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PMID:Specific binding of the type C viral core protein p12 with purified viral RNA. 18 Nov 38

Formaldehyde-fixed Staphylococcus aureus and monospecific antiserum to gp70, the major envelope glycoprotein of murine leukemia virus, were used to immunoadsorb gp70 from Nonidet P40 extracts prepared from surface-radioiodinated murine cells. The labeled gp70 molecules in these cells were linked to a protein of approximately 15,000 daltons via native disulfide bonding. Prior treatment of cells with the reversible, bifunctional, crosslinking reagent dimethyl-3,3'-dithiobispropionimidate, followed by immunoadsorption and two-dimensional diagonal electrophoresis, revealed apparent homodimers and homotrimers of the 85,000-dalton complex. Identical treatment of purified type C RNA tumor virus from murine cells also revealed homodimeric and homotrimeric species, demonstrating similar self-associating tendencies of this glycoprotein in both intact virus and the plasma membrane of nonproducing murine cells. One cross-linked product consistently detected on the surfaces of murine cells was not present after crosslinking of a representative strain of murine leukemia virus.
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PMID:Nearest-neighbor interactions of the major RNA tumor virus glycoprotein on murine cell surfaces. 21 3

The safety and the efficacy of several feline leukemia virus (FeLV) vaccines for 16-week-old kittens were determined. Vaccines were derived from an FL74 lymphoblastoid cell line that has been in continuous tissue culture passage for about 4 years. The vaccines were made from living virus, formaldehyde-inactivated whole FL74 cells, and formaldehyde-inactivated whole virus. The efficacy of each produced vaccine was determined by challenge exposure of vaccinated cats with virulent FeLV. The two formaldehyde-inactivated vaccines were found to be safe for use in kittens. Neither vaccine produce a significant feline oncornavirus-associated cell membrane antigen or virus-neutralizing antibody response, nor did they prevent infection with virulent FeLV. The inactivated whole-virus vaccine, however, did substantially decrease the proportion of kittens infected with virulent FeLV that became persistently viremic. In contrast, the whole FL74 cell vaccine did not reduce the number of infected kittens that became persistently viremic. The live-virus vaccine was found to be both safe and efficacious. About a half of the kittens vaccinated with live virus had transient bone marrow infection that lasted from 2 to 4 weeks. Viral antigen was not detected in peripheral blood, and infective virus was not shed in saliva, urine, or feces during the period that the vaccinal virus could be recovered from the bone marrow. In addition, there was no horizontal spread of vaccinal virus from vaccinated to non-vaccinated cagemates. Within several weeks, vaccinated kittens demonstrated no clinical or hematologic abnormalities and had high serum levels of feline oncornavirus-associated cell membrane antigen and virus-neutralizing antibody. Kittens vaccinated with living FeLV were resistant to infection with virulent virus.
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PMID:Safety and efficacy studies of live- and killed-feline leukemia virus vaccines. 23 Jul 67

Fifteen cases of histologically proven hairy-cell leukaemia (HCL) were studied with immunofluorescence, rosette, and phagocytosis techniques. Unfixed hairy cells (HC) bound all kinds of labelled antiserum; but after fixation with formaldehyde a much more selective binding was observed. In two cases no surface-bound Ig was detected; four cases showed gamma and in nine cases two or three heavy chains were found, alpha and delta being the most frequent. Few cases were clearly positive for mu. The picture was invariably monoclonal with respect to light chains. Cytoplasmic Ig was present in only 3/15 cases; it was always IgM. HC did not form E-rosettes or react with a fluorescent anti-T cell antiserum. No EAIgMC-rosettes were formed. All cases showed Fc receptors, which were detected with EAIgG-rosettes (13/13) or with antigen-antibody complexes (6/6). The density of Fc receptors varied widely. Incubation with latex particles resulted in cell-associated particles in 16-63% of the HC; with Staphylococcus epidermidis, the percentage was 2-36. After enzyme treatment (lysostaphin), however, no ingested bacteria were found, which suggests that HC are essentially non-phagocytic. At least 13 cases were therefore classified as B-cell malignancies.
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PMID:Hairy-cell leukaemia: a B-lymphocytic disorder. 38 Jun 27

The concept that type-C RNA viruses serve as determinants of chemically induced cancer would be supported if immunization against such viruses reduced the incidence of methylcholanthrene-induced sarcomas. A formalin vaccine was employed which was able to protect mice against the development of virus-induced Rauscher leukemia: 8/12 vaccinated mice survived versus 1/12 controls. When mice so immunized were challenged with near-threshold doses of chemical carcinogen, sarcoma incidence and death latency did not differ between vaccinated and control groups: within 10 months, a 320 mug dose of methylcholanthrene induced 100% sarcomas in both groups, while a 64 mug dose induced 62% and 65% tumors in vaccinated and control mice respectively. Thus, a relevant postulate of the oncogene hypothesis could not be supported by these studies. Formalin treatment neutralizes the oncogenic effect of mouse leukemia viruses yiwlding preparations that are immunogenic and can be successfully used as vaccines to protect against virus-induced leukemia (5). The finding of murine leukemia viruses in chemically induced tumors (1, 2) poses the question of whether these viruses are present in the tumors as passengers, or whether they are etiologically involved in the process of tumor induction. An approach to answering this question would be to challenge with chemical carcinogens mice which have been vaccinated with leukemia virus. If the virus were somehow involved in tumor induction, antiviral immunization might conceivably interfere with chemical carcinogenesis. Whitmire and Huebner (9) have reported that mice immunized with formalin-treated leukemia viruses, become resistant to sarcomagenesis by methylcholanthrene. Repetition of this experiment by Gericke and Chandra (6) gave non-significant differences between experimental and control groups. The present paper deals with the effect of immunization against Rauscher leukemia virus upon tumor induction by near-threshold doses of methylcholanthrene.
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PMID:Effect of a Rauscher leukemia virus vaccine upon chemical oncogenesis in the mouse. 102 Oct 12

Two groups of adult CBA mice were immunized with 10-7 allogeneic Moloney lymphoma (YAC) cells. These YAC (H-2a) cells, which were either irradiated with 6000 R (Group i) or were formaldehyde fixed (Group II), were injected i.p. at weekly intervals for 3 weeks. Four days following the last injection, sera and lymphocytes were collected and tested in vitro for activity against either allospecific antigens (H-2d target cells) or viral-specific antigens, namely, Moloney leukemia virus (MLV). Both groups of animals developed measurable cellular and humoral immunity to the virally determined antigens. However, only the animals in Group i, immunized with irradiated cells, developed detectable immunity to H-2d. Immune and control lymphocytes were tested in microcytotoxicity tests and by 51Cr release. Antibody was assessed by complement-dependent cytotoxicity, indirect membrane immunofluorescence, virus neutralization, and antibody-dependent lymphocyte cytotoxicity. Group I serum, which had both anti-MLV and anti-H-2 antibodies, was absorbed with either living or formaldehyde-fixed YAC cells. The living cells were able to remove both H-2 and MLV antibodies. On the other hand, the formaldehyde-fixed cells removed no H-2 antibody but were able to remove MLV antibody, although less efficiently than living cells. These data indicate that formaldehyde fixation selectively impaired the H-2 antigens, leaving the viral antigenicity relatively intact. Differences between the immune responses to MLV-determined antigens and to H-2 antigens were demonstrated in many of the parallel in vitro tests.
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PMID:Comparison of the allospecific and viral-specific immune responses to irradiated versus formaldehyde-fixed allogeneic Moloney lymphoma cells in CBA mice. 109 Mar 67

FAB Cooperative Group has cited 3 or higher percentage in the peroxidase (PO) activity as one of criteria for the diagnosis of acute myeloid leukemia. We have previously reported in two cases of acute myelomonocytic leukemia (M4) that there was a great difference between 3,3'-diaminobenzidine (DAB) and 3-amino 9-ethyl carbazole (3AC) as substrates for PO reaction. In order to confirm the previous result, we extended the cases and compared the PO activities in blood films taken from several leukemic subjects, which were fixed with various kinds of fixatives, using DAB and 3AC as substrates. Their peroxidase activities were also determined through electron microscopy (EM-PO). There were no differences among fixatives and substrates in staining normal granulocytic cells (neutrophils and monocytes) and cells in 13 cases of leukemia, except for two cases, one with M4 and the other with relapse of M2. These showed the highest PO activity with 3AC staining and 10% formaldehyde acetone buffer for fixation. Besides, all types manifested the highest positivity in EM-PO, except for the relapse of M2 that showed a higher positivity in the peroxidase stain by 3AC staining, 10% formaldehyde acetone buffer fixation than the EM-PO. Unlike other leukemic blasts PO reaction products of blast cells of the two cases showed a scattered distribution of microscopic granules. These findings suggested the difference, which was seen in the previous reports, of the PO stain between two substrates might be due not only to sensitivity for staining but to the presence of some heterogeneity such as isoenzyme in the myeloperoxidase.
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PMID:[The sensitivity and specificity of various peroxidase stains--the difference between DAB and 3AC stainings]. 137 54

The cells of some human leukemia-lymphoma T cell lines (JURKAT, MOLT4), B cell lines (DAUDI, U-266) and of myeloid U-937 cell line were characterized for their surface membrane and cytoplasmic marker profiles. The usefulness of some fixation and permeabilization methods of cell membrane for detection of cytoplasmic markers by flow cytometry was studied. The methods of cell fixation in suspension were found to be more sensitive than the methods of cell fixation in smears. With the very short buffered formaldehyde-acetone (BFA) fixation used in this study an optimal penetration of the monoclonal antibodies (MoAbs) through the plasma membrane and specific binding to the appropriate structures were achieved. CD22 antigen was detected in cytoplasm but not on membrane of DAUDI cells. In another B cell line, U-266, CD22 antigen was present both in cell membrane and cytoplasm. The marker corresponding to anti-CD19 MoAb was detected in cytoplasm but was absent on membrane of U-266 cells. Furthermore, the antigen estimated by anti-CD3 MoAb could be detected intracellularly in cells of both T cell lines tested, while it was absent on cell membrane of these cells. The phenotypic study of U-937 cells showed that the majority of cells expressed myeloid associated antigens. In our study the CD14 marker detected on cell surface membrane of U-937 cells was missing in their cytoplasm. The surface antigens remained intact after BFA fixation enabling a simultaneous detection of membrane and cytoplasmic markers in double immunofluorescence studies. Through this combination of markers minor cell populations could be detected. Human hematopoietic cell lines could serve as a reliable model system for a rapid and quantitative immunodiagnosis.
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PMID:Detection of cytoplasmic and surface membrane markers in cells of some human hematopoietic cell lines. 149 22

Leukaemia cells possess a latent form of a cell surface protease referred to as guanidinobenzoatase. Latency is due to complex formation between an inhibitor protein and the cell surface enzyme which is stable under acid conditions but is dissociated with formaldehyde treatment. The latent form of the cell surface protease has been used as a protecting mechanism during a preliminary step to stain all the nuclei of cells with haematoxylin. The enzyme-inhibitor complex was then dissociated and a combination of 9-amino acridine and propidium iodide employed to enable the fluorescent location of cells possessing active guanidinobenzoatase. We were thus able to visualise the nuclei by conventional light microscopy and simultaneously visualise the cell surface of leukaemia cells by fluorescent microscopy. This simple model system has provided technology applicable to the more complex analysis of neoplastic cells in cervical smears.
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PMID:The protective role of a natural inhibitor in the fluorescent location of cells possessing a latent form of cell surface protease. 169 Jul 94


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