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)

Sera from normal (C57BL/6XC3H/Anf)F1(B6C3F1) mice reacted with several biologically distinct murine leukemia virus(es) (MuLV) by radioimmune precipitation assays with the use of purified tritiated leucine-labeled virus. The reactivities of this natural antibody to viral envelope antigens of two laboratory strains (Rauscher and Moloney) and two endogenous mouse C-type viruses (AKR and BALB:virus-2) were further analyzed and compared by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Similar patterns of antibody reactivities to AKR MuLV and the two member viruses of the Friend-Moloney-Rauscher group were found. Three major antigenic determinants of the virus envelope, gp71, gp43, and p15, were recognized by and precipitated natural antibody. In all viruses examined, normal B6C3F1 sera precipitated comparable amounts of gp71 and gp43. However, compared with the other viruses, the amount of p15 (relative to the glycoproteins) precipitating from BALB:virus-2 was significantly lower. This appears to be due to a lesser amount of p15 on the xenotropic virus. While heterologous antisera to purified gp71 and p15 of MuLV reacted to a certain degree with rhabdomyosarcoma virus 114 and rat leukemia virus, natural mouse antibody did not. These results suggest that MuLV have common antigenic determinants recognized by natural antibody, and that the reactivities of natural antibody in an autogenous immune response are restrictive in contrast to immune antibody produced in a heterologous host.
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PMID:Autogenous immunity to endogenous RNA tumor virus: reactivity of natural immune sera to antigenic determinants of several biologically distinct murine leukemia viruses. 5 18

FMR antigens are found on the surface of cells infected with Friend, Moloney, and Rauscher murine leukemia viruses (MuLV). These antigens are serologically distinct from the G cell surface antigens that are found on cells infected with endogenous MuLV (AKR and Gross virus). Cell surface antigens of both virus groups are immunogenic in mice, and immunization with appropriate virus-infected cells leads to the production of cytotoxic antisera. The cytotoxic activity of FMR antisera can be absorbed by disrupted preparations of Rauscher MuLV, but not by AKR MuLV. FMR antisera precipitate the viral envelope proteins gp70, pl5(E), and p12(E) from detergent-disrupted preparations of [3H]leucine-labeled MuLV. The reaction of these antisera with p15(E) and p12(E) proteins is directed against group-specific antigens and can be absorbed with AKR MuLV; in contrast, the reaction of these antisera with gp70 is directed against type-specific antigens and is absorbed only by viruses of the FMR group. In immune precipitation assays with detergent-disrupted 125I surface-labeled cells, FMR antisera react only with type-specific antigens of the viral envelpe protein. On the basis of these findings we conclude that the FMR cell surface antigen is a determinant on the MuLV env gene product.
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PMID:Identification of an FMR cell surface antigen associated with murine leukemia virus-infected cells. 7 90

The glycoproteins of several enveloped viruses, grown in a variety of cell types, are labeled with 35SO4(-2), whereas the nonglycosylated proteins are not. This was shown for the HN and F glycoproteins of SV5 and Sendai virus, the E1 and E2 glycoproteins of Sindbis virus, and for the major glycoprotein, gp69, as well as for a minor glycoprotein, gp52, of Rauscher leukemia virus. The minor glycoprotein of Rauscher leukemia virus is more highly sulfated, with a ratio of 35SO4- [3H]glucosamine about threefold greater than that of gp69. The G protein of vesicular stomatitis virus was labeled when virions were grown in the MDBK line of bovine kidney cells, although no significant incorporation of 35SO4(-2) into this protein was observed in virions grown in BHK21-F line of baby hamster kidney cells. In addition to the viral glycoproteins, sulfate was also incorporated into a heterogenous component with an electrophoretic mobility lower than that of any labeled with 35SO4(-2) and [3H]leucine, this component had a much greater 35S-3H ratio than any of the viral polypeptides and thus could not represent aggregated viral proteins. This material is believed to be a cell-derived mucopolysaccharide and can be removed from virions by treatment with hyaluronidase without affecting the amount of sulfate present on the glycoproteins.
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PMID:Sulfated components of enveloped viruses. 17 Apr 20

The murine leukemia lymphoblast line L5178Y was tested for its early molecular response to the presence of dibutyryl cyclic AMP. Protein synthesis was reversibly inhibited by short durations of hyperthermia, and against this reduced background of protein synthetic activity, early leucine incorporation (30-120 min) was markedly and consistently stimulated by the presence of the cyclic nucleotide. The effect became one of inhibition with extended times of incubation (longer than 120 min).
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PMID:Stimulatory effect of 3', 5'-adenosine monophosphate on protein synthesis in heat-shocked murine leukemia lymphoblasts. 17 78

Some human marrows in culture release particles with oncornavirus-like properties. This study was designed to examine the immunological properties of similar particles in human marrow culture supernates. Leukemic and nonleukemic marrows were cultured for 5-7 days in the presence of [14C]uridine and [3H]leucine or [3H]glucosamine. Labeled supernatant components banding in sucrose gradient densities of 1.20-1.24 g/ml were used as antigen in a double antibody immunoprecipitation assay. The assay was validated by end point titrations and competition with unlabeled antigen; purified myeloma proteins were used as negative controls. Cross-reactivity with mammalian oncornaviruses, as judged by competitive inhibition of precipitation by these viruses, was slight and at the border of the sensitivity of the method. Precipitated antigens analyzed by SDS polyacrylamide gel electrophoresis contained three distinct polypeptides of about 70,000, 45,000 and 30,000 mol wt; these comigrated with the gp 70, pg 45, and p 30 of a murine leukemia virus. Similar polypeptides were obtained from both leukemic and nonleukemic marrow culture supernates. As determined by the radioimmunoprecipitation assay, 32 of 45 leukemic sera (71%), 36 of 45 normal sera (80%), 15 of 19 sera from family contacts of leukemic patients (79%), 14 of 21 cord blood specimens (67%), and 21 of 23 sera (91%) from patients with systemic lupus erythematosus had detectable antibody activity.
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PMID:Antibodies in human sera to oncorna virus-like proteins from normal or leukemia marrow cell cultures. 18 53

The humoral immune responses of NIH Swiss and SWR/J mice immunized with formalin-inactivated AKR or Gross murine leukemia virus, respectively, were examined. Both immune sera had high titers of antibodies detectable in radioimmune precipitation assays using [3H]leucine-labeled AKR virus and in radioimmunoassays using purified virion components. The predominant antibody titers were directed against gp71 and pl15(E). The immune response against gp71 was predominantly type-specific, whereas the reactivity with pl15(E) was predominantly group-specific. A weak immune response against p15 was also detected. Both sera were cytotoxic against cells replicating the AKR-Gross virus type but not against cells replicating Friend murine leukemia virus. This cytotoxicity could be specifically blocked with purified gp71 of AKR murine leukemia virus. Sera from immune NIH Swiss mice neutralized AKR virus, but did not neutralize Rauscher, Scripps, or wild mouse leukemia virus.
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PMID:The humoral immune response of NIH Swiss and SWR/J mice to vaccination with formalinized AKR or Gross murine leukemia virus. 18 11

The amino- and carboxyl-terminal amino acid sequences of proteins (p10, p12, p15, and p30) coded by the gag gene of Rauscher and AKR murine leukemia viruses were determined. Among these proteins, p15 from both viruses appears to have a blocked amino end. Proline was found to be the common NH(2) terminus of both p30s and both p12s, and alanine of both p10s. The amino-terminal sequences of p30s are identical, as are those of p10s, while the p12 sequences are clearly distinctive but also show substantial homology. The carboxyl-terminal amino acids of both viral p30s and p12s are leucine and phenylalanine, respectively. Rauscher leukemia virus p15 has tyrosine as the carboxyl terminus while AKR virus p15 has phenylalanine in this position. The compositional and sequence data provide definite chemical criteria for the identification of analogous gag gene products and for the comparison of viral proteins isolated in different laboratories. On the basis of amino acid sequences and the previously proposed H-p15-p12-p30-p10-COOH peptide sequence in the precursor polyprotein, a model for cleavage sites involved in the post-translational processing of the precursor coded for by the gag gene is proposed.
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PMID:Amino- and carboxyl-terminal amino acid sequences of proteins coded by gag gene of murine leukemia virus. 20 97

The amino acid composition, the COOH-terminal amino acid, and the NH2-terminal amino acid sequence of the first 55 residues of the major internal structural protein, p24, of bovine leukemia virus (BLV) were determined. The compositional data and the results of end-group analysis revealed that, although BLV p24 is chemically distinct, it more closely resembles the p30 structural proteins than the other gag gene products of mammalian retroviruses. It was found that BLV p24 shares the common NH2-terminal proline and COOH-terminal leucine but lacks the common prolylleucylarginine tripeptide and the larger conserved region found near the NH2 terminus of all mammalian type C viral p30s. Alignment of the amino acid sequence of BLV p24 with the previously determined sequence of feline leukemia virus p27 revealed a statistically significant sequence homology. A more distant relationship was found between BLV p24 and other mammalian p30s. The finding of a definite sequence homology between BLV p24 and mammalian type C virus p30s clearly establishes the origin of these contemporary viral proteins from common progenitor genes.
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PMID:Amino-terminal sequence of bovine leukemia virus major internal protein: homology with mammalian type C virus p30 structural proteins. 22 66

The incorporation of 3H-leucine as an indicator of protein synthesis has been studied of blast cells in acute leukaemia and of proliferative normal bone marrow cells. The results demonstrate a significantly higher 3H-leucine incorporation into normal immature cells as compared to leukaemic myeloblasts, also 3H-leucine labelling of lymphoblasts was significantly lower than both the values found in acute leukaemia and normals. Higher protein synthesis was found correlated to the degree of cell immaturity. No significant correlation between 3H-leucine labelled and 3H-thymidine labelled leukaemic blast cells was achieved. A marked decrease in 3H-leucine incorporation by puromycin was demonstrated in three patients with acute myeloid leukaemia.
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PMID:Leucine incorporation into leukaemic blast cells. 29 96

The effect of the naturally occuring amino acids upon melphalan (L-phenylalanine mustard, L-PAM) toxicity to a host sensitive tissue, the granulocyte and macrophage precursor cells of murine bone marrow (CFU-C), was investigated. At physiological concentrations the L isomers of leucine and glutamine were found to be the most effective of the naturally occurring amino acids in reducing drug toxicity. Tyrosine, phenylalanine and methionine also protected murine CFU-C from melphalan toxicity although the amount of protection provided by these amino acids at physiological concentrations was less than that provided by leucine and glutamine. Little difference was observed in the pattern of amino acid protection of murine CFU-C and murine L1210 leukemia cells. Murine CFU-C however were more sensitive to melphalan both in the absence and presence of amino acids.
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PMID:Amino acid conferred protection against melphalan: comparison of amino acids which reduce melphalan toxicity to murine bone marrow precursor cells (CFU-C) and murine L1210 leukemia cells. 44 10


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