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 present resolution (75-100 A) of the conventional scanning electron microscope (SEM) and its ability to image the surfaces of large numbers of whole cells in situ permit the approach of problems such as viral and cell surface antigen localization by immunological labeling with visual markers. Identification of virus and cell surface antigens in situ has been accomplished in indirect reactions by unconjugated markers. Hemocyanin (Hcy) from whelk, Busycon canniculatum, has been developed as an immunospecific marker for virion and cell surface labeling in the electron microscope. Its size (30 x 50 nm) and distinct cylindrical shape permit easy visualization in the SEM and the transmission electron microscope (TEM). The Hcy method involves the preparation of antisera to Hcy in appropriate hosts for use in an unlabeled antibody macromolecule procedure based exclusively on antigen-antibody affinity to couple the macromolecule to the antigen site. Further correlative data from fluorescence microscopy can be obtained from similarly labeled samples by binding fluorescein to the bridging antibodies used in the Hcy technique. The usefulness of the Hcy marker system was demonstrated by employing highly specific antisera to the major envelope and cell surface glycoprotein (gp70) of Rauscher murine leukemia virus (R-MuLV), a type C retrovirus. The antiserum was shown to bind to the virion and cell surfaces of virus-infected cells in the homologous virus-infected cell system. It also demonstrated the expression of R-MuLV gp70-related antigens on a murine cell line Mm5mt/c1 which produces mouse mammary tumor virus (MuMTV), a type B retrovirus. Furthermore, when used in the Hcy marker system the anti-gp70 serum was able to distinguish type B from type C budding virus on the same cell. Methods for the preparation of immunoreagents and labeling of cells are discussed.
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PMID:An unlabeled antibody macromolecule technique using hemocyanin for the identification of type B and type C retrovirus envelope and cell surface antigens by correlative fluorescence, transmission electron, and scanning electron microscopy. 11 48

This work describes the detection, isolation, and partial characterization of a BALB/c mouse fibroblast cell surface antigen. This antigen migrates as a polypeptide of approximately 100,000 daltons in a discontinuous sodium dodecyl sulfate/polyacrylamide gel electrophoresis system, can be labeled by either lactoperoxidase-catalyzed cell surface 125I iodination or metabolic incorporation of [3H]glucosamine, and can be isolated by concanavalin A affinity chromatography. This cell surface glycoprotein is antigenic in BALB/c mice and has been correlated with the rejection of immunogenic tumor cells. Also, antiserum specific for Moloney leukemia virus precipitates the 100,000-dalton cell surface protein from viral and immunogenic spontaneous transformants. This virus-related antigen comigrates on sodium dodecyl sulfate gels with the major iodinated cell surface protein of these transformants. Rabbit antiserum to the purified antigen demonstrates a marked preference for the surfaces of immunogenic tumor cells as compared with normal cells and nonimmunogenic tumor cells.
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PMID:Isolation and characterization of a tumor cell surface antigen from spontaneously transformed BALB/c mouse fibroblasts. 28 13

Human and mouse lymphocytes were surface-labeled by lactoperoxidase-catalyzed iodination, or by galactose oxidase oxidation followed by reduction with tritiated sodium borohydride. The labeled cells were lysed with Nonidet P-40. Proteins binding to Helix pomatia A hemagglutinin (HP) were isolated by affinity chromatography on HP-Sepharose and analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis and autoradiography. A major cell surface glycoprotein (apparent mol. wt. 150 000, using reducing conditions) on human lymphocytes was responsible for almost all binding of HP. This protein was present on normal and malignant thymus-derived lymphocytes, e.g. thymocytes, blood T cells and T leukemia cell lines. It was also found on chronic lymphocytic leukemia cells, one null cell leukemia line, one unidentified leukemia line, one lymphoblastoid cell line of B origin and on one stem cell lymphoma line. In contrast, this protein was not found on various B cells at different steps of differentiation, e.g. four B lymphoma lines or one myeloma line. It was also absent from a histiocytic leukemia line. However, two of the four B lymphoma lines and the myeloma line had another HP-binding surface glycoprotein (mol. wt. 200 000) instead of the 150 000 protein. Studies of mouse lymphocytes similarly showed that thymus-derived lymphocytes (normal and malignant) but not normal adult B cells expressed a major HP-binding surface glycoprotein of apparent mol. wt. 130 000 (reducing conditions).
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PMID:Helix pomatia A hemagglutinin: selectivity of binding to lymphocyte surface glycoproteins on T cells and certain B cells. 30 19

The present resolution (75-100 A) of the conventional scanning electron microscope (SEM) and its ability to image the surfaces of large numbers of whole cells in situ permits the approach of problems such as viral and cell surface antigen localization by immunological labeling with visual markers. Identification of virus and cell surface antigens in situ has been accomplished in indirect reactions by conjugated and unconjugated markers. Hemocyanin (Hcy) from whelk, Busycon canniculatum, has been developed as an immunospecific marker for virion and cell surface labeling in the electron microscope. Its size (approximately 30 x 50 nm) and distinct cylindrical shape permit easy visualization in the SEM and TEM. The Hcy method involves the preparation of antisera to Hcy in appropriate hosts for use in an unlabeled antibody macromolecular procedure based exclusively on antigen-antibody affinity to couple the macromolecule to the antigen site. Further correlative data from fluorescence microscopy can be obtained from similarly labeled samples by binding fluorescein to the bridging antibodies used in the Hcy technique. The usefulness of the Hcy marker system was demonstrated using antisera to the major envelope and cell surface glycoprotein (gp70) of Rauscher murine leukemia virus (R-MuLV), a type C retrovirus. The antiserum was shown to bind to the virion and cell surfaces of virus-infected cells in the homologous virus-infected cell system. It also demonstrated the expression of R-MuLV gp70-related antigens on a murine cell line Mm5mt/c1 which produces mouse mammary tumor virus (MuMTV), A type B retrovirus. Furthermore, when used in the Hcy marker system this antiserum was able to distinguish type B from type C budding virus on the same cell. Examples of other marker systems (ferritin, peroxidase, colloidal gold, and latex) used to show anti-gp70 serum reactivity will be presented to demonstrate their applicability to cell surface labeling studies. Methods for the preparation of immunoreagents and labeling of cells are discussed.
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PMID:Immunologic techniques for the identification of virion and cell surface antigens by correlative fluorescence, transmission electron and scanning electron microscopy. 39 19

The monoclonal antibody termed SN10 (IgG1-k) which was generated and characterized in the present study shows a highly selective reactivity with fresh (uncultured) human leukemia-lymphoma cells. The antigen defined by SN10 is a cell surface glycoprotein composed of a single polypeptide chain of Mr 36,000 and designated as gp36. The primary reactivity of SN10 is against mature B-lineage leukemia-lymphoma cells. For instance, SN10 reacted with all of the 17 B non-Hodgkin's lymphoma specimens, all of the 15 B chronic lymphocytic leukemia specimens, both of the 2 B prolymphocytic leukemia specimens, all of the 3 B hairy cell leukemia specimens, and 2 of the 3 B acute lymphoblastic leukemia specimens tested. Of normal peripheral blood cells, only a marginal reactivity of SN10 was detected with a minor subpopulation (less than 1-4% among different specimens) of isolated B-cells from healthy donors. No significant reactivity of SN10 was detected against any other isolated normal peripheral blood cells which include T-cells, granulocytes, monocytes, erythrocytes, and platelets. Furthermore, no significant reactivity of SN10 was detected against normal bone marrow specimens. In immunohistological studies using frozen tissue sections, SN10 reacted well with malignant lymphomas and showed varying patterns of reaction with hyperplastic reactive lymph nodes. Various normal human tissues tested were unreactive with SN10. In general, glycoprotein 36 was more abundantly expressed on fresh (uncultured) leukemia-lymphoma cells than on cultured leukemia-lymphoma cell lines. No significant amount of circulating SN10 antigen was detected in the plasma of leukemia-lymphoma patients or normal healthy donors. Scatchard plot analysis of direct binding of radiolabeled SN10 to a fresh (uncultured) B non-Hodgkin's lymphoma cell specimen, a fresh B chronic lymphocytic leukemia cell specimen, and DND-39 (an American Burkitt's lymphoma cell line) showed equilibrium constants of 5.2, 5.8, and 6.8 x 10(8) liters/mol, respectively. Thus, SN10 shows a high binding avidity to each of the 3 B leukemia-lymphoma cell specimens tested. Ricin A chain conjugate of SN10 killed leukemia-lymphoma cells effectively, whereas the same conjugate showed no cytotoxicity against control cells. Thus, SN10 bound to target antigen on the cell surface was effectively internalized into the cell. The present results suggest the potential of SN10 for therapy as well as for diagnosis of various forms of leukemia-lymphoma, particularly mature B-lineage leukemia-lymphoma.
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PMID:Monoclonal antibody SN10 which shows a highly selective reactivity with human B leukemia-lymphoma and is effectively internalized into cells. 170 87

Monoclonal antibodies My10, BI.3C5, 12.8, and ICH3 identify a monomeric cell surface glycoprotein (HPCA-1) of 100-120 kD, which is selectively expressed on human hemopoietic progenitor cells. Other tissues are nonreactive with the exception of capillary endothelia and basement membrane in some sites. In addition, the antigen can be detected on cell lines that exhibit characteristics associated with early T cell precursors. HPCA-1 is therefore associated with myeloid, B, and T lineage precursors. Sequential immunoprecipitation and Western blotting studies demonstrate that BI.3C5, ICH3, My10, and an antibody directed against endothelial cells, 188.27, all react with the same glycoprotein species, although the epitopes involved may be distinct. The epitope recognized by BI.3C5 is sialic acid dependent, whereas that recognized by ICH3 is not. The My10 epitope has partial sensitivity to neuraminidase. Competitive/additive binding experiments suggest that these epitopes, although probably distinct, may be closely associated.
Leukemia 1987 May
PMID:Distribution and epitope analysis of the cell membrane glycoprotein (HPCA-1) associated with human hemopoietic progenitor cells. 244 31

We have determined the organization and nucleotide sequence of the gene encoding the human T cell surface glycoprotein CD8 alpha. This gene spans approximately 8 kb and is organized into six exons which encode separate functional domains of the protein. Exon 1 encodes the 5' untranslated region and leader peptide, exon II the Ig V-like region, exon III the hinge-like region, exon IV the transmembrane domain, and exons V and VI the cytoplasmic tail. Alternative splicing that excludes nucleotide sequences from exon IV results in a transcript which encodes a secreted form of the protein. This transcript accounts for approximately 15% of the total CD8 alpha mRNA in human T cell leukemia lines and in normal human tissues. Secreted CD8 alpha protein can be detected in culture supernatants of T cell leukemia lines and PHA-stimulated PBMC by immunoprecipitation with the anti-CD8 alpha mAb OKT8 or with a polyclonal rabbit antiserum specific for the 28 amino acid cytoplasmic domain of CD8 alpha. The secreted CD8 alpha protein forms homodimers; when analyzed by SDS-PAGE, the protein migrates with an apparent molecular mass of 27 or 54 kDa under reducing or non-reducing conditions, respectively. Human secreted CD8 alpha may serve an immunoregulatory role for the interactions of T cells with their targets in vivo.
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PMID:Alternatively spliced mRNA encodes a secreted form of human CD8 alpha. Characterization of the human CD8 alpha gene. 249 67

Two human tumor cell lines exhibiting acquired multidrug resistance (MDR) with increased expression of a cell surface glycoprotein (GP-170) were tested for their sensitivity to human recombinant tumor necrosis factor (rTNF). The drug resistant mutant lines (CEM/V, a T-cell leukemia line resistant to vinblastine, and 8226/D, a multiple myeloma line resistant to doxorubicin), were markedly more sensitive to rTNF in clonogenic assay than were their drug-sensitive parental lines (CEM, 8226). As determined by radioreceptor assay, the number of cell surface receptors for rTNF did not differ on the parental and drug-resistant lines. During the first 24 hours after addition of rTNF, there was a decrease in intracellular ATP content in the CEM/V line but not in the CEM line. No differential effect of rTNF on ATP content was observed between 8226 and 8226/D. As determined by RNA dot-blot analysis, total cellular RNA for GP-170 was increased in the 8226/D cells. After rTNF exposure, expression of total cellular RNA for GP-170 was not altered. Accumulation of radiolabeled doxorubicin by 8226/D cells was not altered by previous or coincubation with rTNF. These findings suggest that the effects of rTNF on MDR cells is not related to TNF receptor number and is mediated at a step subsequent to rTNF binding and not by either inhibition of synthesis of GP-170 or by alteration in the function of the GP-170 efflux pump.
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PMID:Effects of tumor necrosis factor on sensitive and multidrug resistant human leukemia and myeloma cell lines. 279 Jan 97

In the present study, we established a dependable system by which human pre-B- and non-T/non-B-acute lymphoblastic leukemia (ALL) cells are efficiently transplanted into nude mice; the transplanted tumors provide a useful model for investigating the efficacy of antitumor agents in the in vivo therapy of human cancer. NALM-6 (a pre-B-ALL cell line) cells were transplanted under varying conditions as the pre-B-leukemia cells, whereas REH (a non-T/non-B-ALL cell line) cells were transplanted as the non-T/non-B-leukemia cells. Under optimal and near optimal conditions, 71 of 101 X-irradiated mice (70%) developed distinct tumors approximately 2 wk after i.d. inoculation of a mixture of NALM-6 cells and X-irradiated human fibrosarcoma cells. Under the same conditions, 9 of 11 mice (82%) developed tumors following i.d. inoculation of REH cells admixed with X-irradiated human fibrosarcoma cells. Examination of the tumor tissues demonstrated that the tumors are of leukemia origin but not of fibrosarcoma origin. To demonstrate the usefulness of the present tumors for investigating the efficacy of antitumor agents in the in vivo therapy of human cancer, immunotoxins were tested for their specific suppressive activity against growing tumors of the transplanted NALM-6 cells. To this end, monoclonal antibodies SN5 and SN6 which define a common ALL antigen, termed CALLA, and a novel leukemia-associated cell surface glycoprotein, termed gp160, respectively, were separately conjugated with the A-chain subunit of ricin, a plant toxin; CALLA and gp160 are expressed on the cell surface of various human non-T-leukemia cells including NALM-6 cells. The conjugates of SN5 and SN6 with ricin A-chain (RA) showed specific activity against the leukemia cells but not against control cells in an in vitro assay. To investigate their in vivo efficacy in suppressing tumor growth, nude mice which had been inoculated i.d. with NALM-6 cells 25 days in advance and bore distinct palpable tumors (5 to 6 mm in diameter) were divided into five groups. One group of mice was nontreated as a control. Each of the remaining four groups of mice was given an injection of one of the following agents: (a) purified control mouse IgG (IgG1); (b) purified antibodies SN5 (IgG1) and SN6 (IgG1); (c) control IgG-RA conjugate; or (d) SN5-RA and SN6-RA. Tumors in all mice of the first four groups including the untreated group grew continuously, causing the mice to die.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Efficient transplantation of human non-T-leukemia cells into nude mice and induction of complete regression of the transplanted distinct tumors by ricin A-chain conjugates of monoclonal antibodies SN5 and SN6. 296 82

Two characteristics of cell surface molecules involved in the regulation of cell proliferation are altered expression in relation to growth phase in normal cells and overexpression in transformed cells. Here, we describe a similar pattern of expression for a 130-kD cell surface glycoprotein (gp 130) in human cells. Synthesis and cell surface expression of gp130 were greatly increased in both virally and chemically transformed fibroblasts, fibrosarcomas, a squamous cell carcinoma of the skin, and T cell leukemia lines. Furthermore, gp130 expression was induced in serum-starved fetal fibroblasts by serum stimulation, and in fresh T cells by various activating agents. Expression in response to serum stimulation was associated primarily with the transition from a quiescent state (G0) into the cell cycle (G1).
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PMID:A transformation-associated 130-kD cell surface glycoprotein is growth controlled in normal human cells. 325 55


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