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Biomedical subjects

S Gillis

Publications and source records attributed to S Gillis.

At least 145 records · Page 8Linked to original sources
PubMed1988

Stimulation of B-chronic lymphocytic leukemia populations by recombinant interleukin-4 and other defined growth-promoting agents.

Monoclonal populations from 10 cases of phenotypically well-characterized B-chronic lymphocytic leukemia (B-CLL) and from a single case of hairy cell leukemia were assessed for their ability to respond by mitogenic stimulation to a number of agents described as growth-promoting for normal B cells. These included the recombinant factors interleukin-1 (IL1), IL2, IL4, IL5, and gamma-interferon, partially purified B cell growth factor (BCGF), B cell stimulatory factor 2 (BSF2), and a CDw40 antibody to the Bp50 antigen. With only few exceptions, no factor or combination of factors stimulated B-CLL populations directly to DNA synthesis. By marked contrast, the hairy cells were responsive to IL4, BCGF, and the CDw40 antibody. B-CLL cells could become responsive with the inclusion of the phorbol ester TPA (12-O-tetradecanoylphorbol-13-acetate) as co-stimulant such that half of the populations were now activated by IL4, particularly when BCGF was also present. Populations refractory to IL4 were, nonetheless, still responsive to BCGF. In only three cases was a significant effect seen with IL2. gamma-interferon could be either inhibitory or stimulatory and, in a few cases, modulated specifically the effects of IL4. In contrast to normal B cell activations, neither the CDw40 antibody nor a calcium ionophore synergized with TPA for stimulating the majority of B-CLL populations. BSF2 was stimulatory in the two cases examined while both IL1 and IL5 were ineffective where studied. No simple correlation was observed between the patterns of responsiveness and the expression of a panel of CD markers assayed on cells both freshly isolated and after TPA stimulation. The data demonstrate a functional heterogeneity not disclosed by simple phenotypic analysis and also indicate the range of activities which can impinge on the growth regulation of monoclonal B cell populations.

Antibodies, Monoclonal↗
PubMed1988

IL-1 and IFN-gamma increase vascular permeability.

We examined the effect of cytokines on vascular permeability in vivo. Wistar rats received intradermal injections of various cytokine preparations and the permeability index (delta PI) was calculated from the difference between the absorption values of cytokine- and vehicle-treated skin sections after the extraction of accumulated Evans blue vital dye. Injections of a mixture of recombinant interleukin-1 alpha and beta (Il-1 alpha, IL-1 beta) and interferon-gamma (IFN-gamma) caused a maximal increase of permeability after 30 min (delta PI = 2). The administration of single recombinant cytokines revealed that the increase of permeability is mainly due to the action of IL-1 beta (delta PI = 1.4) and IFN-gamma (delta PI = 2.9) (P less than 0.001) at doses of 1-20 microU per injection site. IL-1 alpha slightly increased vascular permeability, whereas recombinant IL-2 and recombinant tumour necrosis factor alpha had no significant effects. Histological observations revealed significantly increased numbers of degranulated mast cells in skin sections pretreated with IL-1 beta (P less than 0.005) or IFN-gamma (P less than 0.001). The cytokine-mediated rise of vascular permeability could be suppressed by pretreatment of the animals with the vasoactive amine antagonizing drugs methysergide, pizotifen and cyproheptadine. Our experiments indicate an important role of IL-1 beta and IFN-gamma as vasoactive substances besides their function as hormone-like messengers between leucocytes.

Animals↗
PubMed1988

Differential induction of class II gene expression in murine pre-B-cell lines by B-cell stimulatory factor-1 and by antibodies to B-cell surface antigens.

We have previously reported that BSF-1 and an alloantibody to the B-cell differentiation antigen Lyb2 induce class II gene expression in two Ia negative pre-B-cell lines. Two questions were asked in these studies. The first question is whether the different stimuli which we and others have shown to induce class II expression in B-cells act via the same signal transduction mechanisms. The second question is whether the traditionally accepted pathway of B-cell differentiation, as defined by immunoglobulin (Ig) gene rearrangement, is applicable to other events that occur during B-cell differentiation. In this report, we have therefore examined a large panel of pre-B-cell lines at different stages of Ig gene rearrangement in an attempt to 1) identify the stage in B-cell development where class II gene expression occurs and where it becomes inducible by BSF-1 or anti-Lyb2, and 2) compare the signal transduction mechanisms used by these ligands. The majority of pre-B-cell lines tested did not express BSF-1 receptors and were consequently noninducible for class II by BSF-1; such cell lines were, however, inducible for class II expression by anti-Lyb2 and, in addition, by antibodies to the B220 membrane glycoprotein. The induction of class II molecules by BSF-1 and by anti-Lyb2 and anti-B220 differed in several respects: 1) Induction by anti-Lyb2 and anti-B220 did not require the presence of BSF-1 receptors; 2) BSF-1 selectively induced class II antigen expression while anti-Lyb2 and anti-B220 induced the expression of other surface markers as well; and 3) PGE2 inhibited BSF-1 but not antibody-mediated class II induction. Finally, the presence of receptors for BSF-1 and the baseline expression of cell surface Ia was shown to be unlinked to Ig gene rearrangement and expression in this series of pre-B-cell lines. The independent regulation of Ia and Ig genes observed here may reflect a branching rather than a linear pathway for B-cell differentiation. The differentiation of pre-B-cells to mature Ig-secreting cells should probably not be defined solely by rearrangement of Ig genes, since this is likely to represent an oversimplified view of B-cell differentiation.

Animals↗
PubMed1988

Development and characterization of two neutralizing monoclonal antibodies to human interleukin-1 alpha.

Mice immunized with homogeneous recombinant interleukin-1 alpha (IL-1 alpha) protein developed specific serum titers to the immunogen. Hybridomas resulting from the fusion of the immune spleen or lymph node cells to myeloma cells were analyzed by an antibody capture assay in which the antigen was present in solution. This assay enabled us to isolate two hybridomas secreting antibodies (designated 2F4 and 4G12) that recognized IL-1 alpha and not interleukin-1 beta as judged by the ability of the antibodies to: (a) precipitate IL-1 alpha, (b) inhibit the binding of 125I-IL-1 alpha to the IL-1 receptor on EL4 cells, (c) inhibit the biological activity of IL-1 alpha as measured in a lectin-induced, IL-1-dependent thymocyte proliferation assay. In a double determinant assay configuration, both antibodies, in conjunction with rabbit polyclonal anti-IL-1 alpha antibodies, could detect nanogram concentrations of IL-1 alpha in solution. Cross-inhibition studies indicated that the 2F4 and 4G12 antibodies bind to the same or spatially related epitopes since each can inhibit the binding of the other to IL-1 alpha.

Animals↗
PubMed1988

Synergistic interaction of hematopoietic colony stimulating and growth factors in the regulation of myelopoiesis.

Synergistic interactions in the regulation of myelopoiesis have been noted in vitro and in vivo and are discussed. Moreover, data is presented to highlight such synergistic interactions in vitro and in vivo. It is shown that purified recombinant human B-cell stimulating factor-1/interleukin-4 (rh BSF-1/IL-4) synergizes with rh Granulocyte (G)-Colony Stimulating Factor (CSF), but not with rh Granulocyte-Macrophage (GM)-CSF, rh IL-3, or rh Macrophage CSF (CSF-1) to enhance colony formation in vitro by normal human bone marrow cells. This synergism is restricted to granulocyte progenitors. Also, it is shown that rh G-CSF or rh CSF-1 enhance the proliferation of granulocyte-macrophage progenitor cells (CFU-GM) in vivo in mice pretreated with human lactoferrin, and when added together these preparations of CSF act synergistically. It is apparent that a true understanding of how myeloid blood cell production is regulated requires insight into how molecules collaborate with or antagonise one another.

Animals↗
PubMed1988

Augmentation of donor bone marrow engraftment in histoincompatible murine recipients by granulocyte/macrophage colony-stimulating factor.

T cell depletion of donor bone marrow can prevent graft v host disease (GVHD) in human and murine marrow graft recipients. However, engraftment in the recipient may be compromised as a consequence of donor marrow T cell depletion. The effect of recombinant murine granulocyte/macrophage colony-stimulating factor (rmu GM-CSF) on engraftment and hematologic reconstitution was evaluated in a murine allogeneic bone marrow transplantation (BMT) model involving T cell depletion of marrow. Before transplantation into irradiated mice differing at major and minor histocompatibility loci, rmu GM-CSF was preincubated with T cell-depleted donor marrow. When low degrees of engraftment were noted in control recipients, treatment of donor marrow with high concentrations of rmu GM-CSF led to enhanced engraftment. Ex vivo donor graft incubation with rmu GM-CSF or a single in vivo injection of rmu GM-CSF were both effective means of promoting engraftment. When the engraftment rate in control recipients was high, rmu GM-CSF did not have an identifiable effect. Only slight increases in hematologic recovery were detected regardless of the rate of engraftment. Neither post-BMT survival nor marrow stem cell capacity was affected by rmu GM-CSF incubation. Furthermore, growth factor administration did not have a significant effect on the incidence of GVHD in recipients of non-T cell-depleted bone marrow splenocyte preparations. In vitro natural killer-mediated target cell lysis was not altered by incubation of effector cells with rmu GM-CSF. These results demonstrate the potential of ex vivo rmu GM-CSF treatment of donor marrow to facilitate engraftment across extensive histo-compatibility barriers.

Animals↗
PubMed1987

Beta transforming growth factors are potential regulators of B lymphopoiesis.

Members of the transforming growth factor beta (TGF-beta) family of polypeptides were found to be potent in vitro inhibitors of kappa light chain expression on normal bone marrow-derived and transformed cloned pre-B cells, and of the maturation of these cells to mitogen responsiveness. The inhibition by TGF-beta was selective in that Ia expression was not blocked. Together with the observations that LPS, IL-1, NZB serum factors, IL-4, and IFN-gamma preferentially induced either kappa or Ia, or both, on a pre-B cell line, these results further suggest that acquisition of Ig and class II molecules is independently controlled by different antagonists as well as agonists. In addition, kappa chain induction by IFN-gamma does not appear to be as sensitive to TGF-beta downregulation as that stimulated by other factors tested, and this raises the possibility that activation of the same gene may result from different transmembrane signaling pathways. In contrast to the inhibitory effects of TGF-beta on kappa acquisition by pre-B cells and on kappa increase after exposure of mature B cells to LPS, as measured by kappa RNA levels and/or surface fluorescence, no inhibition was observed on unstimulated spleen B cells or on two cloned B cell lines that constitutively produce kappa. Thus, TGF-beta may function during specific stages of B cell differentiation by inhibiting initiation of, or increased transcription of Ig genes, and therefore, may be an important negative regulator of B lymphopoiesis. It is the first natural substance found to have this effect.

Animals↗
PubMed1987

The in vivo effects of interleukin 1. I. Bone marrow cells are induced to cycle after administration of interleukin 1.

We have previously reported that interleukin 1 (IL-1) administration 20 hr before irradiation protects mice from lethal effects of radiation. The recovery of total nucleated bone marrow cells and of hematopoietic progenitor cells was enhanced in IL-1 treated, as compared to untreated, irradiated mice. This suggested that IL-1 administration may affect the cells in the bone marrow of normal mice. Intraperitoneal administration of recombinant IL-1 resulted in bone marrow cell enlargement and increased cycling of these enlarged cells. In addition, the capacity of bone marrow cells from IL-1 treated mice to proliferate in response to granulocyte macrophage-colony-stimulating factor (GM-CSF) in cell suspension cultures was enhanced. The above effects were not genetically restricted as C57BL/6, B6D2F1, C3H/HeN, and C3H/HeJ mice showed similar responses. A comparative study showed that 100 ng of IL-1 was much more effective in stimulating bone marrow cells by the above criteria than 5 micrograms GM-CSF. Since IL-1, unlike CSF, can not be demonstrated to have a direct in vitro stimulatory effect on bone marrow cells, the aforementioned in vivo effects of IL-1 are presumably mediated by other hematopoietic growth factors. We have previously shown that IL-1 induces the appearance of high titers of CSF in the serum. Consequently hematopoietic growth factors that are generated at local sites following IL-1 administration may mediate the observed cell cycling effect.

Animals↗
PubMed1987

Granulocyte-macrophage colony-stimulating factor augments the primary antibody response by enhancing the function of antigen-presenting cells.

Purified, recombinant-derived murine granulocyte-monocyte colony-stimulating factor was found to enhance the primary in vitro immune response to SRBC by murine spleen cells. In determining the mechanism of this augmentation, it was found that only splenic adherent cells and neither resting nor activated T cells nor B cells expressed specific receptors for GM-CSF. When splenic adherent cells were pulsed briefly with GM-CSF before addition to macrophage-depleted cultures, they reconstituted the PFC response to a significantly greater degree than did control macrophages. Splenic adherent cells incubated overnight with SRBC plus GM-CSF were also more efficient antigen-presenting cells than splenic adherent cells incubated with antigen alone. The mechanism of this enhanced antigen presentation was found to be due to a GM-CSF-dependent increase in the level of IL 1 secretion and Ia antigen expression. Consistent with these data was the finding that GM-CSF augmented IL 2 production by splenic T cells in response to suboptimal concentrations of Con A. Finally, the day 5 in vivo antibody response (as measured by serum titers) of mice immunized with a low dose of SRBC was enhanced by two daily inoculations of GM-CSF. Thus, the role that GM-CSF plays in augmenting immune responses may not be solely accounted for by its ability to cause the proliferation or differentiation of macrophages, but more than likely includes its ability to enhance the function of antigen-presenting macrophages.

Animals↗
PubMed1987

Effect of infection with murine recombinant retroviruses containing the v-src oncogene on interleukin 2- and interleukin 3-dependent growth states.

The cloned murine interleukin 3 (IL 3)-dependent cell lines FD.C/1, 32Dc1-23, and KP3 can each be switched to interleukin 2 (IL 2)-dependent growth states. Replication-defective retroviral vectors have been used to introduce the v-src oncogene into each of these cell lines maintained in either an IL 3- or an IL 2-dependent growth state. These cell lines maintained in an IL 3-dependent growth state were converted to lymphokine-independent growth after infection with v-src. These same cells maintained in an IL 2-dependent growth state and infected with v-src maintained strict lymphokine dependence for growth. Another cloned murine IL 3-dependent cell line, GM, can be switched to a granulocyte-macrophage colony-stimulating factor (GM-CSF)-dependent growth state. GM cells maintained as IL 3- or GM-CSF-dependent cells readily converted to a lymphokine-independent growth state when infected with v-src. These experiments indicate that either there exist differences in the biochemical mechanisms of signal transduction through the IL 3- and IL 2-specific receptors, or developmental processes associated with the switching of cells to an IL 2-dependent growth state influence expression of the v-src gene product. These cell lines offer new ways not only for analyzing biochemical pathways that regulate cell growth, but also for analyzing the control of oncogene expression.

Animals↗
PubMed1987

Localization of human mononuclear cell interleukin 1.

The detection and localization of interleukin (IL) 1 in human monocytes was carried out by flow cytometry using monoclonal antibodies to IL-1 alpha and IL-1 beta proteins. IL-1 alpha was detected on the surface of monocytes and the surface expression increased following lipopolysaccharide activation. No demonstrable IL-1 beta protein could be observed on the cell surface by antibody staining, while both IL-1 alpha and IL-1 beta could be visualized intracellularly by the appropriate monoclonal antibodies following acetone permeabilization of the monocytes. Further experiments with cell associated IL-1 revealed that most of the biological activity of human monocytes could be inhibited by affinity purified polyclonal antibodies to IL-1 alpha protein, whereas no inhibitory activity was observed with IL-1 beta specific antibodies. These data support the hypothesis that a differential localization of IL-1 alpha and IL-1 beta exists within human blood-derived monocytes.

Antibodies, Monoclonal↗
PubMed1987

Differential bioassay of interleukin 2 and interleukin 4.

The T cell-derived lymphokines interleukin 2 (IL-2) and interleukin 4 (IL-4, originally BSF-1) both exhibit T cell growth-promoting activity. Recent observations that T cell lines commonly used as indicator cells in IL-2 bioassays also proliferate in response to IL-4 demonstrate the lack of specificity of these bioassays for IL-2. In this report we describe a bioassay method to differentiate IL-2 and IL-4 through the parallel use of two T cell lines with defined lymphokine specificity. The IL-2-responsive CT6 cell line, when used in conjunction with the IL-2- and IL-4-responsive HT-2 cell line, allows for the differentiation of IL-2 and IL-4 in conditioned media.

Animals↗
PubMed1987

The interleukin-1 receptor binds the human interleukin-1 alpha precursor but not the interleukin-1 beta precursor.

Both IL-1 alpha and IL-1 beta are initially translated as approximately Mr 30,000 polypeptides and processed to approximately Mr 17,500 prior to, or during, release from macrophages. The current study utilizes an in vitro transcription-translation system to produce these four forms of IL-1 directly from cloned cDNAs, in order to investigate the relative receptor binding and biological activities of the proteins. The data show that the initial translation product from IL-1 beta mRNA must be processed in order to bind to the IL-1 receptor and hence express biological activity. By contrast, the initial translation product of IL-1 alpha mRNA can bind to the IL-1 receptor without further proteolytic processing. These data suggest that the IL-1 biological activity previously associated with proteins having Mr values in the range 30,000-40,000 is due to IL-1 alpha gene products.

Binding, Competitive↗
PubMed1987

Production of IL-1 alpha and IL-1 beta by clones of EBV transformed, human B cells.

An EBV transformed B-cell line was derived from peripheral blood cells from a single donor. B-cell clones were isolated from that line and analyzed for transcription of IL-1 genes, production of biologically detectable IL-1 and antigen presenting capabilities. One clone was found to secrete IL-1 activity into tissue culture medium, and to express the gene for IL-1 alpha. Three other clones were positive for cell surface IL-1 activity but no activity could be detected in culture supernatants. Those clones express the gene for IL-1 beta but not IL-1 alpha. All clones were approximately equal in their ability to present antigen to resting and primed T cells.

Antigen-Presenting Cells↗
PubMed1987

Expression, purification and characterization of recombinant murine granulocyte-macrophage colony-stimulating factor and bovine interleukin-2 from yeast.

Expression and secretion of two lymphokines, murine granulocyte-macrophage colony-stimulating factor (MuGM-CSF) and bovine interleukin-2 (BoIL-2), to levels of 50-60 mg per liter were achieved by placing these cDNAs in a Saccharomyces cerevisiae expression vector that utilized the yeast alcohol dehydrogenase-2 promoter and alpha-factor leader peptide. These lymphokines were purified to homogeneity by direct application of the crude yeast medium to reversed-phase high-performance liquid chromatography. Despite the fact that both lymphokines contain at least one N-glycosylation site and have identical N-terminal residues (Ala-Pro-Thr), recombinant (R) GM-CSF was found to be heterogeneously glycosylated by yeast while RBoIL-2 was secreted without glycosylation. Additionally, approximately 40% of the RGM-CSF was found to be proteolytically cleaved after the second amino acid residue, while RBoIL-2 was found to be intact.

Animals↗
PubMed1987

Synergistic myelopoietic actions in vivo after administration to mice of combinations of purified natural murine colony-stimulating factor 1, recombinant murine interleukin 3, and recombinant murine granulocyte/macrophage colony-stimulating factor.

Combinations of low dosages of purified murine hematopoietic colony-stimulating factors (CSFs)--L-cell CSF type 1 (CSF-1), recombinant interleukin 3 (IL-3), and recombinant granulocyte/macrophage CSF (GM-CSF)--were compared with single CSFs for their influence on the cycling rates and numbers of bone marrow granulocyte/macrophage, erythroid, and multipotential progenitor cells in vivo in mice pretreated with human lactoferrin. Lactoferrin was used to enhance detection of the stimulating effects of exogenously administered CSFs. Concentrations of CSFs that were not active in vivo when given alone were active when administered together with other types of CSF. The concentrations of CSF-1, IL-3, and GM-CSF needed to increase progenitor cell cycling rates were reduced by factors of 40-200, 10-50, and 40- greater than 400, respectively; the concentrations needed to increase progenitor cell numbers were reduced by factors of 40-500 (CSF-1), 20-80 (IL-3), and greater than 40- greater than 200 (GM-CSF) when these forms of CSFs were administered in combination with low dosages of one of the other forms of CSFs. The results demonstrate that different CSFs can synergize when administered in vivo to increase the cycling rates and numbers of marrow hematopoietic progenitor cells. These findings may be of relevance physiologically to the regulation of myeloid blood cell production by CSFs.

Animals↗
PubMed1987

Determination of the minimum polypeptide lengths of the functionally active sites of human interleukins 1 alpha and 1 beta.

Interleukin 1 (IL-1) is a two-member family of proteins (IL-1 alpha and IL-1 beta) that mediates a diverse series of immune and inflammatory responses. These two proteins have only 26% amino acid homology yet bind to the same receptor. It is of importance to define the active sites of these molecules in order to understand their receptor interactions and the mechanisms involved in their multiple biological functions. We report here the localization of the biologically active portions within the initial polypeptide translation products. An in vitro transcription and translation system was used to generate specific fragments of each of the IL-1 molecules, which then were assayed for receptor binding capability and biological activity. Using this system, we have demonstrated that core sequences of amino acids for IL-1 beta (numbers 120-266) and 140 amino acids for IL-1 alpha (numbers 128-267) must be left intact to retain full biological activity and further that the biological activities of the IL-1 polypeptides parallel their receptor binding capabilities.

Amino Acid Sequence↗