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D L Urdal

Publications and source records attributed to D L Urdal.

54 records · Page 3Linked to original sources
PubMed1985

Induction and upregulation by interleukin 2 of high-affinity interleukin 2 receptors on thymocytes and T cells.

We show that purified recombinant interleukin 2 (rIL-2) alone induces the expression of high- and low-affinity interleukin 2 (IL-2) receptors in vitro on human T cells and thymocytes that have not been activated previously by lectins or other inducing agents. IL-2 receptors are expressed after 24 hr, as determined by the binding of 125I-labeled monoclonal anti-IL-2 receptor antibody 2A3, which binds equally to high- and low-affinity receptors. High-affinity receptors were distinguished from low-affinity receptors by the binding of 125I-labeled IL-2 to T cells and by the proliferative response of thymocytes to IL-2, in concentrations that selectively interact with the high-affinity class of IL-2 receptors. The IL-2-induced proliferation of thymocytes in vitro induced by IL-2 alone is dependent upon the concentration of IL-2 and is inhibited by monoclonal anti-Tac antibody, indicating that the proliferative response is mediated by the binding of IL-2 to the receptors. In addition, we demonstrate that IL-2 augments the number of high-affinity receptors on concanavalin A-activated thymocytes. These results document that IL-2 acts as a hormone that induces the activation of thymocytes and T cells, as evidenced by the de novo induction of biologically active, high-affinity IL-2 receptors. IL-2 also upregulates the expression of high-affinity IL-2 receptors on activated thymocytes. These observations illustrate the biologic importance of the regulatory role of IL-2 in the immune response.

Cells, Cultured↗
PubMed1985

Generation of anti-peptide monoclonal antibodies which recognize mature CSF-2 alpha (IL 3) protein.

The colony-stimulating factor CSF-2 alpha (IL 3) has been purified to homogeneity, the protein sequenced, and the gene encoding this lymphokine cloned. Knowledge of the protein sequence permitted the synthesis of peptides corresponding to the amino terminus of the molecule. These peptides, after conjugation to palmitic acid, were used to immunize mice. Spleen cells from mice immunized with one of these peptides (CSF-2 alpha 1-14) were fused with the myeloma cell line NS-1. The fusion resulted in the isolation of two hybridoma cell lines, designated 6A5 and 4D4, that secreted antibodies that were specific for the immunizing peptide. The antibodies did not react with a closely related peptide CSF-2 alpha 7-16. The antibodies were capable, however, of recognized CSF-2 alpha protein as judged by the ability of the antibodies to remove CSF-2 alpha activity from culture medium of PHA-stimulated LBRM-33-5A4 cells, to immunoprecipitate radiolabeled CSF-2 alpha protein, and to detect CSF-2 alpha protein bound to nitrocellulose membranes.

Animals↗
PubMed1984

Lymphokine purification by reversed-phase high-performance liquid chromatography.

Reversed-phase high-performance liquid chromatography has been used to purify to homogeneity two different lymphokines. Human IL-2 was purified on a C8 reversed-phase column in pyridine-acetate-propanol followed by chromatography on a C18 reversed-phase column in trifluoroacetic acid-acetonitrile. Protein sequence analysis of in situ-generated cyanogen bromide peptides obtained from this preparation established the homogeneity of this material and confirmed the amino acid sequence predicted from the published DNA sequence. Murine CSF-2 alpha was purified on a C18 reversed-phase column in trifluoroacetic acid-acetonitrile followed by chromatography on the same column in pyridine-acetate-propanol. The final preparation yielded a single band on a sodium dodecyl sulfate-polyacrylamide gel with a molecular weight of 24,500.

Amino Acid Sequence↗
PubMed1984

Purification and chemical characterization of the receptor for interleukin 2 from activated human T lymphocytes and from a human T-cell lymphoma cell line.

The cell surface receptor for interleukin 2 plays a central role in the biology of this T-cell growth factor. A combination of affinity chromatography, high-performance liquid chromatography, and NH2-terminal protein sequencing was used to purify and chemically characterize the interleukin 2 receptor both from phytohemagglutinin-activated T cells and from the human T-cell lymphoma cell line HuT-102. The receptor isolated from HuT-102 cells was purified 16,000-fold to homogeneity as evidenced by (i) a final specific activity close to the theoretical specific activity of 18,182 fmol of receptor per microgram of protein, (ii) a single band on polyacrylamide gel electrophoresis with an Mr of 55,000, and (iii) a unique, unambiguous NH2-terminal protein sequence. The receptor purified from phytohemagglutinin-activated T lymphocytes had an Mr of 60,000 but it had the same NH2-terminal protein sequence.

Amino Acid Sequence↗
PubMed1984

Purification to homogeneity and partial characterization of interleukin 2 from a human T-cell leukemia.

A method utilizing reversed-phase high-performance liquid chromatography has been developed for the purification to homogeneity of interleukin 2 (IL-2) isolated from a human T-cell leukemia. A final purification of 500,000-fold was obtained with a specific activity of pure IL-2 of 10(9) units/mg. The amino acid analysis of natural IL-2 is strikingly similar to the composition deduced from sequence analysis of a cDNA coding for human IL-2. Protein sequence analysis of CNBr-derived peptides yields data consistent with the sequence proposed from cloned cDNA. The availability of homogeneous IL-2 will allow accurate biological studies of its activity free from the contamination of the numerous lymphokine species that are known to be co-produced with IL-2 during the induction procedure.

Amino Acid Sequence↗
PubMed1984

Interleukin 2 administered in vivo induces the growth of cultured T cells in vivo.

The capacity of exogenous IL 2 to induce the growth of antigen-activated T lymphocytes in vivo was evaluated. The in vivo growth of adoptively transferred T lymphocytes that had been previously cultured long-term with IL 2 was initially examined, because in vitro such T cells are exquisitely dependent upon exogenous IL 2 for proliferation and survival. Daily administration of IL 2 in vivo, beginning on the day of cell transfer, induced these IL 2-dependent long-term cultured T lymphocytes to proliferate in vivo, and the magnitude of in vivo growth was proportional to the dose of IL 2 administered. The capacity of IL 2 to induce the in vivo growth of antigen-activated T cells not previously exposed in vitro to exogenous IL 2 was similarly studied. T lymphocytes from the spleens of immune mice, activated by 5-day culture with tumor antigen before transfer, survived poorly in vivo when injected with antigen alone, but demonstrated marked proliferation in vivo in response to antigen and exogenous IL 2. By contrast, immune spleen cells transferred with antigen, but without prior culture, proliferated without supplementary exogenous IL 2. Moreover, the growth of noncultured donor T cells was not augmented by the administration of exogenous IL 2, implying that noncultured spleen cells immune to tumor antigens can produce sufficient amounts of endogenous IL 2 in vivo to sustain maximal T cell growth over the time period examined. Importantly, the ability of exogenous IL 2 to induce donor T cell growth in vivo correlated with its ability to function in vivo to augment the anti-tumor efficacy of specifically immune donor T cells in models for the adoptive therapy of disseminated antigenic murine leukemia. Thus, the current studies highlight the potential of exogenous IL 2 to induce T cell growth in vivo and suggest that the administration of IL 2 in vivo may be useful for augmenting T cell responses that are relatively deficient in the production of endogenous IL 2.

Animals↗
PubMed1984

Biochemical comparison of murine colony-stimulating factors secreted by a T cell lymphoma and a myelomonocytic leukemia.

Factors that stimulate the proliferation and differentiation of murine bone marrow cells have been purified from a cloned T cell lymphoma, LBRM-33, and a cloned myelomonocytic leukemia cell line, WEHI-3. These colony-stimulating factors (CSF) have been purified by sequential fractionation by using salt precipitation, gel filtration, anion and cation exchange chromatography, and high pressure liquid chromatography. Both LBRM-33 and WEHI-3 cells secrete a CSF species with similar chemical and biologic properties. This CSF species appears to exist in two forms, termed CSF-2 alpha and CSF-2 beta, both of which stimulate the growth of bone marrow cells in the granulocyte, macrophage, megakaryocyte, mast cell, and erythrocyte lineages, as well as the growth of a CSF-dependent cell line, FDC-P2. These properties of CSF-2 alpha and -2 beta are similar to those reported for interleukin 3, hematopoietic cell growth factor, mast cell growth factor, and persisting cell growth factor. However, LBRM-33 cells secrete another CSF species, not produced by WEHI-3 cells. This CSF species, unique to LBRM cells, is termed here CSF-2 gamma and it stimulates the proliferation of granulocytes and macrophages from bone marrow but does not support the growth of FDC-P2 cells.

Animals↗
PubMed1983

Characterization of tumor-associated ganglio-N-triaosylceramide in mouse lymphoma and the dependency of its exposure and antigenicity on the sialosyl residues of a second glycoconjugate.

Ganglio-N-triaosylceramide (GalNAc beta 1 leads to 4Gal beta 1 leads to 4Glc beta 1 leads to 1Cer), a tumor-associated marker for L5178 cells, was previously reported to separate on thin layer chromatography into three distinct bands (bands a, b, and c). The present paper describes the characterization of these bands and the factor that determines the degree of glycolipid exposure at the cell surface and its antigenicity. 1) The resolution of ganglio-N-triaosylceramide into three bands was found to be due to molecules having different fatty acid compositions. Band a contained nervonic (C24:1) and lignoceric (C24:0) acids, band b contained palmitic acid (C16:0), and band c contained alpha-hydroxypalmitic acid. 2) Surface labeling of L5178c127 cells with galactose oxidase/sodium borotritide, followed by fluorography of the isolated glycolipids, revealed that all three bands were exposed on the surface of the cell. However, treatment of cells with sialidase before treatment with galactose oxidase resulted in a 10-fold increase of label incorporated into ganglio-N-triaosylceramide. Since no sialylated form of ganglio-N-triaosylceramide was detected on these cells, and no change in the chemical amount of this glycolipid could be detected, the increase of label into this molecule was due to the exposure by sialidase of a normally cryptic glycolipid. The exposure of ganglio-N-triaosylceramide after sialidase treatment was also reflected by the increased sensitivity of these cells to monoclonal antibodies to the glycolipid and complement after enzyme treatment. Thus, the results provide clear evidence that crypticity, as well as antigenicity, of a membrane glycolipid is determined by the degree of sialylation in a second membrane glycoconjugate.

Animals↗
PubMed1983

The mechanism of augmentation of natural killer cell activity by syngeneic tumor cells: role of macrophage-derived factor in NK boosting.

The role of natural killer (NK) cells in controlling tumor growth was investigated using an NK-susceptible (c127v-IC2) and an NK-insusceptible (c127av) subline of the lymphoma L5178Y. Syngeneic DBA/2 mice inoculated intraperitoneally with c127v-IC2 tumor cells survived significantly longer than did c127av-bearing mice. Similarly, c127v-IC2, but not c127av tumor cells, were found to augment NK activity of spleen and peritoneal exudate cells in both DBA/2 and BALB/c nu/nu mice when inoculated into the peritoneal cavity. C127v-IC2 tumor cells incubated with either DBA/2 or BALB/c nu/nu spleen cells in vitro boosted NK activity and induced the production of gamma-type interferon (IFN), whereas incubation with c127av tumor cells induced neither NK activity nor IFN. Two kinds of cells cooperated in the production of IFN in response to c127v-IC2 tumor cells, namely, cells which were nonadherent, bore asialo-GM1, NK-1.2 and a low level of Thy-1.2 antigen and thus closely resembled NK cells, and those which were adherent and phagocytic and lacked both asialo-GM1 and NK-1.2 markers, presumably macrophages. Further analysis strongly suggested that c127-v-IC2 tumor cells stimulate macrophages to produce factor(s) which can induce the production of IFN by NK cells. The induced IFN was shown to be of the gamma type by its lability at pH 2.0 and insusceptibility to anti-IFN alpha, beta serum. This suggests a novel pathway for NK cell activation, and strongly supports the importance of macrophages and NK cells in natural resistance against certain tumors.

Animals↗
PubMed1983

A granulocyte reactive monoclonal antibody, 1G10, identifies the Gal beta 1-4 (Fuc alpha 1-3)GlcNAc (X determinant) expressed in HL-60 cells on both glycolipid and glycoprotein molecules.

1G10, a monoclonal IgM antibody that identifies a differentiation antigen on human granulocytes and a subpopulation of monocytes, was found to react specifically with glycosphingolipids bearing the Gal beta 1-4(Fuc alpha 1-3)GlcNAc hapten (X determinant). This carbohydrate determinant was found on both glycolipid and glycoprotein molecules isolated from HL-60 cells (a promyelocytic leukemia cell line). Thus, this highly conserved carbohydrate-defined determinant previously described on mouse embryonic and mouse and human carcinoma cells is also expressed as a tissue-specific differentiation antigen on normal human granulocytes.

Antibodies, Monoclonal↗
PubMed1983

Factors affecting expression of glycolipid tumor antigens: influence of ceramide composition and coexisting glycolipid on the antigenicity of gangliotriaosylceramide in murine lymphoma cells.

Gangliotriaosylceramide (Gg3Cer) was previously described as a tumor-associated antigen in murine L5178Y lymphoma [Young, W. W., Jr., and Hakomori, S., Science (Wash. D.C.), 211: 487-489, 1981]. This paper describes the major factors affecting the expression of Gg3Cer at the surface of various clones of L5178Y lymphoma. Of 26 sublines that were recloned, six cell lines showing different degrees of Gg3Cer expression at the cell surface were used for analysis of the glycolipid composition as related to its cell surface antigenicity. Three remarkable correlations between glycolipid composition and the antigenicity of Gg3Cer have been found: (a) high-expressor sublines were characterized by a large proportion of a unique molecular species of Gg3Cer having alpha-hydroxypalmitic acid in its ceramide moiety in striking contrast to low expressors which did not contain this molecular species; (b) low expressors contained a large quantity of ganglio-N-tetraosylceramide (Gg4Cer) and NeuAc alpha 2 leads to 3Gal beta 1 leads to 3GalNAc beta 1 leads to 4Gal beta 1 leads to 4Glc beta 1 leads to 1 Cer (GM1b) gangliosides, whereas these glycolipids were almost absent in high-expressor clones; and (c) nonexpressors, which were converted from the high expressors in vivo through immunotherapy with the monoclonal antibodies to Gg3Cer, contained a large quantity of ganglio-N-tetraosylceramide and NeuAc alpha 2 leads to 3Gal beta 1 leads to 3GalNAc beta 1 leads to 4Gal beta 1 leads to 4Glc beta 1 leads to 1Cer. The nonexpressors should have an induced enzyme system to metabolize Gg3Cer to ganglio-N-tetraosylceramide and NeuAc alpha 2 leads to 3Gal beta 1 leads to 3GalNAc beta 1 leads to 4Gal beta 1 leads to 4Glc beta 1 leads to 1Cer. Three factors, i.e., ceramide composition, coexisting glycolipids, and an antibody-dependent glycolipid change, are therefore important in determination of glycolipid antigenicity and antigen modulation by antibodies. The ceramide composition may affect glycolipid organization in membranes, and the coexisting glycolipid having a longer carbohydrate chain may mask the accessibility of antibody to the antigenic glycolipid. The antigenic modulation by the action of the antibody in vivo may be based on activation of a new glycosyltransferase.

Animals↗
PubMed1982

Selective depletion of NK cell activity in vivo and its effect on the growth of NK-sensitive and NK-resistant tumor cell variants.

Intravenous injection of rabbit anti-asialo-GM1 serum, an antiserum previouslY shown to eliminate splenic natural killer (NK) activity in vitro, profoundly depressed NK activity in CBA, DBA/2 and BALB/c nu/nu mice. The effect on NK activity was selective, as treatment of mice with anti-asialo-GM1 serum did not affect the development of other cytotoxic cells including cytotoxic macrophages following injection of poly I:C, or cytotoxic T cells in response to allogeneic cells. The role of NK cells in controlling tumor cell growth was investigated using an NK-sensitive (cl 27v-1C2) and an NK-resistant (cl 27av) subline of the murine lymphoma L5178Y. Initial studies showed that cl 27v-1C2 cells were at least 100 times less tumorigenic than were cl 27av cells in both syngeneic DBA/2 mice and BALB/c nu/nu mice. In addition, treatment of DBA/2 mice with poly I:C, which boosted NK activity, markedly depressed the growth of cl 27v-1C2 cells, but not of cl 27av cells. On the other hand, treatment of DBA/2 mice and BALB/c nu/nu mice with anti-asialo-GM1 serum led to a marked increase in tumorigenicity of cl 27v 1C2 cells, but had no effect on the tumorigenicity of cl 27av cells. In addition, the protection against cl 27v-1C2 growth afforded by poly-I:C treatment was abrogated by injection oif anti-asialo-GM1 serum. The possibility that the effects observed were caused by binding of the injected antibodies to the tumor cells was minimized by: (1) using a clone of tumor cells (cl 27v-1C2) that lacks chemically detectable asialo-GM1, and (2) pretreating animals with anti-asialo-GM1 rather than administering antiserum and tumor cells concurrently. These studies provided compelling evidence that NK cells could play an active role in controlling tumor growth. Selective depletion of NK activity by injection of anti-asialo-GM1 serum is a method which would be generally applicable to studying the role of NK cells in disease processes.

Animals↗
PubMed1982

NK cell-target interactions: approaches towards definition of recognition structures.

NK cells lyse an uncommonly wide range of cell types, implying either that they (the NK cells) have clonally distributed receptors each of which is capable of interacting with a very limited number of cell types or, alternatively, that susceptible target cells share a common characteristic. A number of experimental approaches have suggested that the cytotoxic 'specificity' of NK cells is not clonally distributed. Thus, clones of NK cells, established from mouse spleen cell suspensions, showed no greater restriction in the spectrum of target cells which they could lyse, than did the parent spleen cell populations from which they were derived. It seems likely therefore that the wide range of target cell types that can be lysed by NK cells share common cell surface characteristics which render them susceptible. As lysis results from membrane-membrane interactions, it seemed logical that a search for 'hallmarks' of NK susceptibility should begin with a detailed examination of the plasma membrane of susceptible cells. Analysis of one pair of lymphoma cell variants, selected on account of their markedly different susceptibility to NK cells, suggests that cell surface glycoconjugates may be of significance in determining those effector cell-target cell interactions that lead to lysis. This review outlines attempts to characterize such glycoconjugates.

Animals↗
PubMedDate not supplied

The cell surface receptors for interleukin-1 alpha and interleukin-1 beta are identical.

Interleukin-1 (IL-1) is a factor that can induce proliferation of murine T lymphocytes and can elicit a variety of other biological responses. These include bone resorption, fibroblast proliferation, acute phase protein release from hepatocytes, cartilage breakdown and fever. This spectrum of activities is consistent with a role for IL-1 as a mediator of inflammation. Recently, sequence data have shown that there are at least two members of the IL-1 family; these distantly related proteins have been termed IL-1 alpha and IL-1 beta. We have found previously that both murine T cells and fibroblasts possess a relative molecular mass (Mr) approximately 80,000 (80K) plasma membrane receptor for human IL-1 beta. We show here that the receptor for IL-1 alpha on both murine and human cells is identical to that for IL-1 beta. This result raises the issue of what separation, if any, there might be between the biological activities of IL-1 alpha and IL-1 beta.

Animals↗