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)

The C-type viruses found in long-term cultures. New Bolton Center (NBC) cell lines, of peripheral lymphocytes from leukemic cattle and in short-term cultures of bovine buffy coat(BC) cells share an immunofluorescent(IF)antigen detected in the cytoplasm of infected cells as well as an antigen demonstrable in gel diffusion experiments. Therefore the viruses from these cultures most likely represent different isolates of the putative bovine leukemia virus (BLV). The BLV precipitin antigen is analogous to the group specific (gs) antigens of the leukemia viruses of other species in that it is soluble, ether resistant, and apparently located within the virion. These observations, together with results showing that the specificity of the BLV precipitin antigen differs from that of the gs antigen of other mammalian leukemia viruses, indicate that the former antigen represents the intraspecies (gs-1) determinant of BLV. Antibodies to the precipitin viral antigen were found in 82% of cattle with leukemia and in 40% of clinically normal adult cattle in multiple-case herds. These groups of animals also had fluorescent antibodies to the virus, but with significantly higher frequencies (100% and 76%, respectively). On the other hand, in leukemia-free herds, precipitating antibodies were not found and the incidence of fluorescent antibodies was only 3%.
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PMID:Further studies on the antigenic properties and distribution of the putative bovine leukemia virus. 5 37

Short-term cultures of bovine leukemic lymphocytes release virus particles with biochemical properties of RNA oncogenic viruses. These particles, tentatively called bovine leukemia virus (BLV), have a high molecular weight RNA-reverse transcriptase complex and a density of 1.155 g/ml in sucrose solutions. Molecular hybridizations between BLV/[3H]cDNA and several viral RNAs show that BLV is not related to Mason-Pfizer monkey virus, simian sarcoma associated virus, feline leukemia virus, or avian myeloblastosis virus. These results were confirmed by hybridization between BLV 70S RNA and [3H]cDNA synthesized in the various viruses tested. The high preference of BLV reverse transciptase for Mg++ as the divalent cation suggests that BLV might be an atypical mammalian leukemogenic "type C" virus. DNA-DNA hybridization studies using BLV [3H]cDNA as a probe strongly suggest that the DNA of bovine leukemic cells contains viral sequences that cannot be detected in normal bovine DNA.
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PMID:Bovine leukemia virus: an exogenous RNA oncogenic virus. 5 16

The major internal polypeptide of the bovine leukemia virus (BLV) was purified to homogeneity with the use of gel filtration and affinity chromatography. Like previous results, the protein had a molecular weight of 25,000 daltons as determined by electrophoresis in polyacrylamide gels with sodium dodecyl sulfate. More than 90% of the 125I-labeled protein was precipitated by bovine sera that reacted in immunofluorescence tests with acetone-fixed BLV-infected cells. In contrast, minimal precipitation (less than 5%) was observed with sera from 36 cattle in leukemia-free herds; these sera, negative by immunofluorescence, included six samples that had high titers of antibodies to the foamy-like bovine syncytia virus (BSV). Antisera prepared against several other oncornaviruses or the Mason-Pfizer monkey virus (M-PMV) did not bind the BLV p25 protein. Conversely, the labeled p30 polypeptides of several oncornaviruses tested did not react with bovine sera that had high titers of antibodies to BLV p25. Competitive radioimmunoassay(s) (RIA) also failed to detect cross-reactions between BLV p25 protein and the internal polypeptides of other mammalian and avian oncornaviruses, M-PMV, or foamy-like BSV. The RIA for BLV p25 antigen was also highly sensitive and specific for the detection and quantitation of the antigen in virus preparations and cell homogenates.
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PMID:Detection, quantitation, and characterization of the major internal virion antigen of the bovine leukemia virus by radioimmunoassay. 6 63

Short term cultures of bovine leukemic lymphocytes release virus particles with biochemical properties of RNA oncogenic viruses. These particles, tentatively called Bovine Leukemia Virus (BLV) have a high molecular weight-reverse transcriptase complex and a density averaging 1.155 g/ml in sucrose solutions. Molecular hybridizations between BLV-3H cDNA and several viral RNAs show that BLV is not related to Mason-Pfizer Monkey Virus (MPMV) Simian Sarcoma Associated Virus (SSV-1) Feline Leukemia Virus (FeLV) or Avian Myeloblastosis Virus (AMV). Rauscher Leukemia Virus (RLV) exhibits a slight but reproducible relatednesse to BLV. The high preference of BLV reverse transcriptase for Mg++ as the divalent cation suggests that BLV might be an atypical mammalian leukemogenic type C virus. Hybridization studies using BLV 3H cDNA as a probe suggest that the DNA of bovine leukemic cells contains viral sequences that cannot be detected in normal bovine DNA.
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PMID:Bovine leukemia virus: an exogenous RNA oncogenic virus? 6 82

Sera from some leukemic cattle contain an antibody that inhibits the reverse transcriptase activity of the bovine leukemia virus. The antibody is not directed against the synthetic template or the major internal and envelope viral antigens. The antibody failed to inhibit the DNA polymerases of the murine leukemia virus, simian sarcoma-associated virus, avian myeloblastosis virus, or Escherichia coli. Conversely, the bovine leukemia virus enzyme was not inhibited by antibody against the reverse transcriptases of other C-type viruses. These findings agree with previous results showing that the major internal bovine leukemia virus protein lacks the known interspecies- and intraspecies-specific antigenic determinants indentified in the homologous proteins of other oncornaviruses.
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PMID:Inhibition of the reverse transcriptase of bovine leukemia virus by antibody in sera from leukemic cattle and immunological characterization of the enzyme. 6 83

A new retravirus (SMRV) isolated from a squirrel monkey, Saimiri sciureus, has an Mg2+-dependen reverse transcriptase and a buoyant density of 1.17 g/cm3 in sucrose and 1.21 g/cm3 in cesium chloride, similar to the mouse mammary tumor virus and the Mason-Pfizer monkey virus. The polypeptide patter of SMRV as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis was distinct from the reported polypeptide patterns of known retraviruses. Four major polypeptides of molecular weights 40,000, 20,000, 14,000 and 8,000 were resolved in virus propagated in human, mink, and canine cells. In A204 human rhabdomyosarcoma cells, a protein of 73,000 daltons (gp73) represented the major viral glycoprotein as determined by [3H]glucosamine labeling. Additional proteins were also observed, but their presence depended on the cell type in which the virus was propagated. In both species-and interspecies-specific assays, no antigenic relatedness was observed between SMRV and Mason-Pfizer monkey virus, mouse mammary tumor virus, baboon endogenous virus (BaLV), woolly monkey virus (SSV-1), murine leukemia virus, endogenous feline type C virus (RD-114), bovine leukemia virus, and equine infectious anemia virus. These findings indicate that SMRV represents a new retravirus and the first isolate from a New World monkey.
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PMID:Characterization of a retravirus isolated from squirrel monkeys. 6 28

The results of five years studies on the possibility of experimental induction of bovine leukemia with purified BLV and different BLV-containing materials demonstrated that inoculation of calves with purified BLV (structures of 1.14-1.17 g/ml density in 20-60% sucrose gradient) can induce oncornavirus infection and bovine leukemia. From 41 experimentally infected calves 9 showed evidence of bovine leukemia. 5 of these 9 animals were from a group of 22 calves inoculated with purified BLV. Diagnosis of bovine leukemia in these 9 animals was established by hematologic (3 animals) and histologic method (6 animals). BLV was isolated from leukocytes of all of them. It was shown also that before the development of bovine leukemia the development of oncornavirus infection takes place. But only a small part of the animals with oncornavirus infection and presence of antibodies became ill with typical forms of hemoblastosis. The investigation of the role of milk and blood cells in milk in bovine leukemia transmission was also carried out. The presence was demonstrated of oncornavirus structures antigenically identical with BLV in milk and reproduction of these structures in blood cells being present in milk. These results, and also the induction of bovine leukemia, in cattle by rearing with raw milk from cattle with leukemia, allow us to suppose the possible routes of bovine leukemia transmission in nature.
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PMID:Leukogenic properties of purified BLV and possible routes of its transmission with blood cells present in milk. 8 27

Sera from 3 cows with the adult form of lymphosarcoma inhibited release of leukemia virus from a cell line of fetal lamb spleen infected with bovine leukemia virus (BLV). Sera from 5 to 7 cattle experimentally infected with BLV also suppressed virus release. The inhibition of virus release was reversible. Sera from cattle with the calf form and the thymic form of lymphosarcoma and normal bovine control sera did not repress virus release.
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PMID:Inhibition of bovine leukemia virus release. 16 11

Sprague-Dawley rats were given ip injections of bovine culture and sheep cultures of bovine leukemia virus (BLV) and Gross passage-A leukemia virus [MuLV(G)]. Sera were tested to BLV antigens. BLV did not induce tumors in Sprague-Dawley rats, but the rats were susceptible to MuLV(G) at low doses.
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PMID:Lack of infectivity of bovine leukemia (C-type) virus to rats. 17 2

Sixty-nine sheep were infected with bovine leukemia virus from bovine lymphosarcoma materials. Twenty-four developed lymphosarcoma and died from 13 to 66 (average, 29) months later. Circulating lymphocytes were increased to leukemia levels (70,000 to 403,000/cu mm blood) in only eight sheep within 2 to 3 months of death. Various lymph nodes and visceral organs including heart, abomasum, uterus, kidneys, and urinary tract were commonly affected as in cattle with the adult form of lymphosarcoma. In one sheep the skin was involved. The liver was involved in only one case. This was in contrast to more frequent involvement reported in literature for naturally occurring lymphosarcoma. The neoplasms in experimental sheep are regarded as a mixture of reticulum or histiocytic cells and lymphoid cells with transitional forms supported by a usually sparse and diffuse fibroplasia and a web of silver-staining reticulin fibers.
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PMID:Pathology of lymphosarcoma in sheep induced with bovine leukemia virus. 17 3


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