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)

Inbred strain 2 guinea pigs immunized with L2C leukemia cells produced antibodies to L2C cells detected by 125I-protein A assay. L2C-associated tumor antigens were reacted with syngeneic antisera and analyzed by immunoprecipitation and SDS-polyacrylamide gel electrophoresis. These sera recognized idiotypic determinants on surface IgM molecules of L2C cells but did not recognize any determinants on normal strain 2 spleen cells. Thus, determinants on IgM molecular act as tumor-associated antigens in the L2C system and can be detected by syngeneic sera.
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PMID:Identification of a tumor-associated antigen of the guinea pig L2C leukemia by using syngeneic antisera. 7 93

It was shown previously, that an antiserum directed against highly purified fractions of migration inhibitory factor inhibits delayed hypersensitivity reactions in vivo and in vitro. Using radiolabeling techniques we determined that the anti-lymphokine serum reacted primarily with three lymphocyte activation products (m.w. 60,000, 45,000, and 30,000) all of which had a similar isoelectric point of 5.2. The cellular origin of this material was investigated. It was found that activated B cells, B leukemia cells (L2C), and growing fibroblasts produced material of a similar m.w. as analyzed on SDS-PAGE. No cross-reaction was found with radiolabeled products of activated murine and human lymph node cells and of SV 40-infected African green monkey kidney cells. The isoelectric point of the reactive material from B cells, leukemia cells, and fibroblasts was determined at 5.2. In addition to material with pI 5.2, lymph node cells also produced material with pI 3.5 to 4.5, which focused at pH 5.0 to 5.4. After neuraminidase treatment macrophage migration inhibitory activity in fibroblast culture supernatants could be absorbed specifically to insolubilized anti-lymphokine antibody. These findings suggests that lymphoid and nonlymphoid cells are capable of producing molecules whose physicochemical and functional properties appear to be identical.
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PMID:Antibodies to guinea pig lymphokines. VII. Reactivity with products of lymphoid and nonlymphoid cells. 9 76

The protein and glycoprotein composition of Kirsten murine leukaemia-sarcoma virus (KiMSV(KiMuLV) was studied using SDS-polyacrylamide gel electrophoresis. Twenty-three polypeptides and three glycoproteins were detected following electrophoresis by staining with Coomassie blue and PAS or by autoradiography of isotopically labelled virus. Protein components were assigned positions in the virus particle, envelope, nucleoid or intermediate area based on iodination with lactoperoxidase and sedimentation in potassium citrate equilibrium gradients. The KiMSV (KiMuLV) envelope contained 11 polypeptides and three glycoproteins. The virus nucleoid and intermediate area were each composed of six proteins. The protein composition of KiMSV(KiMuLV) was highly reproducible when virus was harvested from cells of the same subcluture generation. However, the protein profiles were altered with repeated in vitro passages of the virus-producing cell line.
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PMID:Proteins of Kirsten murine leukaemia-sarcoma virus: localization within the virus particle by iodination and fractionation techniques. 16 14

Profiling of murine leukemia virus (MuLV) proteins by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE) has revealed a low-molecular-weight protein which does not appear in the corresponding region of viral protein profiles obtained by gel filtration in 6 M guanidine hydrochloride. This protein species, termed p15(E), is easily demonstrable in MuLV isolates for which the viral p15 and p12 proteins have almost identical electrophoretic mobilities; this leaves a protein slightly larger than these two in the PAGE system unaccounted for in the gel filtration system. However, antiserum against the void volume fraction of the gel filtration eluate precipitated the p15(E) component from solubilized, radiolabeled virions, as shown by SDS-PAGE analysis of such immunoprecipitates. Comparative radioprecipitation analyses of this type revealed that for various MuLV isolates p15(E) was distinguishable from p15 in terms of serological reactivities, relative mobilities in gel electrophoresis, and relative efficiencies of labeling with individual amino acids. Thus it appears that, as is the case for avian oncornaviruses, MuLVs contain seven major structural proteins.
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PMID:Chromatographic separation and antigenic analysis of proteins of the oncornaviruses. V. Identification of a new murine viral protein, p15(E). 16 8

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 synthesis and processing of feline leukemia virus (FeLV) polypeptides were studied in a chronically infected feline thymus tumor cell line, F-422, which produces the Rickard strain of FeLV. Immune precipitation with antiserum to FeLV p30 and subsequent sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) were used to isolate intracellular FeLV p30 and possible precursor polypeptides. SDS-PAGE of immune precipitates from cells pulse-labeled for 2.5 min with [35S]methionin revealed the presence of a 60,000-dalton precursor polypeptide (Pp60) as well as a 30,000-dalton polypeptide. When cells were grown in the presence of the proline analogue L-azetidine-2-carboxylic acid, a 70,000-dalton precursor polypeptide (Pp70) was found in addition to Pp60 after a 2.5-min pulse. The cleavage of Pp60 could be partially inhibited by the general protease inhibitor phenyl methyl sulfonyl fluoride (PMSF). This partial inhibition was found to occur only if PMSF was present during pulse-labeling. Intracellular Pp70 and Pp60 and FeLV virion p70, p30, p15, p11, and p10 were subjected to tryptic peptide analysis. The results of this tryptic peptide analysis demonstrated that intracellular Pp70 and virion p70 were identical and that both contained the tryptic peptides of FeLV p30, p15, p11, and p10. Pp60 contained the tryptic peptides of FeLV P30, P15, and P10, but lacked the tryptic peptides of P11. The results of pactamycin gene ordering experiments indicated that the small structural proteins of FeLV are ordered p11-p15-p10-p30. The data indicate that the small structural proteins of FeLV are synthesized as part of a 70,000-dalton precursor. A cleavage scheme for the generation of FeLV p70, p30, p15, p11, and p10 from precursor polypeptides is proposed.
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PMID:Analysis of intracellular feline leukemia virus proteins II. Generation of feline leukemia virus structural proteins from precursor polypeptides. 19 17

To examine the protein proximity and subunit organization of type C retroviruses, preparations of AKR murine leukemia virus were treated with bifunctional cross-linking reagents and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The cross-linked components obtained were characterized by immunoprecipitation with monospecific antisera against purified viral proteins, followed by SDS-PAGE analysis both before and after cleavage of the cross-links. With these procedures, complexes of both viral envelope and core components were identified. The major envelope subunit obtained was a large (apparent molecular weight of 450,000 to 500,000), glycosylated complex, composed of four to six gp70-p15(E) subunits. This complex was detected over a 100-fold range of cross-linker concentration and thus seems to represent a particularly stable viral substructure. The cross-linked complexes of the core proteins consisted of oligomers of p30 dimers, suggesting that the p30 dimer is a basic structural unit of the viral core. When virion preparations, which had previously been disrupted with the nonionic detergent Nonidet P-40, were cross-linked, the envelope complex was still observed, indicating that this structure is stable in the presence of Nonidet P-40. A similar envelope structure was observed for feline leukemia virus, suggesting that such a complex may be a conserved feature of oncornavirus structure.
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PMID:Structural studies of retroviruses: characterization of oligomeric complexes of murine and feline leukemia virus envelope and core components formed upon cross-linking. 22 13

Human granulocyte 6 phosphogluconate dehydrogenase has been totally purified from a single patient with chronic granulocytic leukaemia. 48 mg of protein, of specific activity 20 IU per mg of protein, have been obtained in the course of three different steps only. The overall yield was 30 p. cent and the purification was 100 folds. Purified 6 phosphogluconate dehydrogenase was homogeneous when tested in acrylamide and acrylamide SDS gel electrophoresis or in immunodiffusion. The enzyme was immunologically identical in red blood cells, blood platelets and normal leukocytes. The fixation of both substrates, NADP-+ and 6 phosphogluconate, seemed to proceed through a non ordered mechanism. NADPH was an inhibitor strictly competitive with respect to NADP-+ and non competitive with respect to 6 phosphogluconate. 2-3 Diphosphoglycerate seemed to be able to bind on both the fixation sites of NADP-+ and 6 phosphogluconate. The inhibition by ATP was competitive with 6 phosphogluconate and non competitive with NADP-+. 6 phosphogluconate dehydrogenase was inactivated by SH reagents and was partially protected against this inactivation by both substrates. Both substrates protected the enzyme against thermal inactivation. The influence of ionic strength, pH and ions have been studied, and the results have been compared to those reported by other authors for erythrocyte enzyme.
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PMID:Human granulocyte 6 phosphogluconate dehydrogenase. Purification by elective elution with NADP+, immunological and kinetic properties. 23 66

Platelets from a patient with eosinophilic leukaemia were not aggregated by ristocetin. The defect was not corrected by normal human plasma and was due to a platelet abnormality. The patient's platelets also showed a diminished sensitivity to aggregation by bovine factor VIIIVWF. The defect was not associated with a prolonged bleeding time. No abnormalities were detected in ADP, collagen or thrombin-induced platelet aggregation. Biochemical studies showed that the platelets were deficient in sialic acid. This deficiency was associated with a reduced staining for glycoprotein I following SDS-polyacrylamide gel electrophoresis. The results suggest an acquired platelet surface abnormality.
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PMID:A platelet defect in a patient with eosinophilic leukaemia: absent ristocetin-induced platelet aggregation associated with a reduced platelet sialic acid content. 45 58

The IgE receptor of human basophils was purified by using simple and repetitive affinity chromatography on human IgE-Sepharose. Basophils were partially purified from peripheral blood of patients with chronic myelogenous or basophilic leukemia. Cells were labeled with 125I by using the lactoperoxidase method and were solubilized with nonionic detergent. Elution of IgE-Sepharose with 0.5 N acetic acid, 1% NP-40 allowed recovery of active IgE receptor. Analysis of human IgE receptor by SDS polyacrylamide gel electrophoresis with 10% gels demonstrated one major radioactive peak with an apparent m.w. of 58,000 to 68,000, somewhat larger than rat IgE receptor. The purified human IgE receptor was active since approximately 10 to 42% of labeled receptor could specifically rebind to insolubilized human IgE. Rebinding was blocked by nanomolar concentrations of soluble human IgE or rat IgE but not by human or rat IgG, heat-inactivated human IgE, or heat-aggregated human IgG; thus it appears that rat IgE receptor. The relative abilities of active rat IgE and active human IgE to inhibit human IgE receptor rebinding could not be precisely determined because of the limitations in assessing the proportion of human IgE that retains receptor-binding activity.
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PMID:Characterization of the IgE receptor isolated from human basophils. 48 84


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