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Biomedical subjects

S Gillis

Publications and source records attributed to S Gillis.

At least 109 records · Page 6Linked to original sources
PubMed1989

Induction of lymphokine-activated killer activity by interleukin 4 in human lymphocytes preactivated by interleukin 2 in vivo or in vitro.

In an attempt to augment the generation of human cytotoxic effector cells for potential cancer therapy with interleukin 2 (IL2) and lymphokine-activated killer (LAK) cells, the effect of interleukin 4 (IL4) on LAK cell induction was studied. In normal human peripheral blood lymphocytes (PBL), IL4 does not induce LAK activity and inhibits LAK induction by IL2. However, since lymphocyte activation, such as with antigen or mitogen, can render them responsive to IL4, the ability of IL4 to induce LAK activity in lymphocytes preactivated in vivo or in vitro with IL2 was investigated. PBL obtained from 12 patients with advanced cancer 1 to 3 days after IL2 therapy and from eight healthy control subjects were cultured 4 to 5 days with or without IL4 and/or IL2 and then tested for LAK activity as assessed by lysis of Daudi in a 4-h 51Cr release assay. In normal PBL, IL4 failed to induce LAK activity and consistently inhibited LAK induction by a suboptimal concentration of IL2 (10 units/ml). By contrast, IL4 induced LAK activity in PBL from seven of twelve IL2-treated patients and augmented LAK induction by the suboptimal IL2 in PBL from five of twelve IL2-treated patients. With an optimal LAK-inducing concentration of IL2 (1000 units/ml), IL4 less consistently inhibited LAK induction in normal PBL and had a variable effect upon LAK induction in PBL from IL2-treated patients. IL4 induced LAK activity in PBL obtained from a cancer patient after, but not before, systemic IL2 therapy. Similarly, IL4 induced LAK activity in normal PBL only after they had been preincubated with IL2. Thus, IL4 induces LAK activity in lymphocytes preactivated by IL2 in vivo or in vitro. Fluorescence-activated cell sorting revealed that the LAK activity, whether induced by IL4 or by IL2, was mediated largely by non-T (CD5-) natural killer-like (CD56+) cells. The results suggest a regulatory relationship between IL2 and IL4 in the induction and/or maintenance of LAK activity, which might be exploited to augment the generation of cytotoxic cells for lymphokine-mediated immunotherapy of human cancer.

Antigens, CD↗
PubMed1989

IL-4 inhibits H2O2 production and antileishmanial capacity of human cultured monocytes mediated by IFN-gamma.

The effect of IL-4 on the IFN-gamma-induced state of activation of cultured human monocytes was investigated with regard to their ability to produce hydrogen peroxide and their antileishmanial capacity towards the intracellular parasite Leishmania donovani. IL-4 was found to inhibit the IFN-gamma-dependent hydrogen peroxide production of monocytes. Treatment of monocytes with IFN-gamma (200 to 600 U/ml) for 48 h increased the hydrogen peroxide production fourfold above background. Coincubation of the monocytes with IL-4 (1 to 1000 U/ml) and IFN-gamma (200 to 600 U/ml) inhibited this increase by 50 to 100%. IL-4 alone did not modulate the hydrogen peroxide production of monocytes. Pretreatment of monocytes with IL-4 for 20 min to 3 h was already effective in preventing the IFN-gamma response. Addition of IL-4 not later than 6 h after the start of incubation with IFN-gamma was necessary for an optimal inhibitory effect. IL-4 also inhibited the IFN-gamma-induced antileishmanial capacity of monocytes: IFN-gamma (1000 U/ml) induced a 54 +/- 10% reduction in the number of parasites. Monocytes treated with combinations of IL-4 (100 to 1000 U/ml) and IFN-gamma (1000 U/ml) were unable to reduce the parasite numbers. IL-4 alone did not alter the uptake of Leishmania donovani nor induce antileishmanial activity. These results demonstrate that IL-4 disables human cultured monocytes to respond to IFN-gamma activation.

Animals↗
PubMed1989

Recombinant human IL-1 alpha and -1 beta potentiate IgE-mediated histamine release from human basophils.

In this study, we have explored the relationship between interleukins and human basophil activation. Previous studies by ourselves and others have found that recombinant human (rh) IL-3 causes histamine release. The ability to release histamine has also been claimed for IL-1 but we cannot confirm this. In experiments with the basophils of 29 donors (excluding one D2O responder), histamine release with 100 ng/ml rhIL-1 alpha was 1.3 +/- 1% (SEM), whereas with rhIL-1 beta, it was 0.8 +/- 1%. Both IL-1 alpha and -1 beta were also used at concentrations of 0.01 to 1000 ng/ml without causing release. Neither increasing the Ca2+ concentration nor adding D2O or cytochalasin B caused IL-1 alpha and -1 beta to become secretagogues. rhIL-1, however, did augment IgE-dependent histamine release. The enhancement was similar with both rhIL-1 alpha and -1 beta, i.e. they were dose-dependent between 0.1 and 3 ng/ml and reached a plateau from 3 to 100 ng/ml. At submaximal histamine release (less than 10%), there was enhancement of three IgE-dependent secretagogues: 125% with goat anti-human IgE (n = 7), 215% with Ag E (n = 10), and 260% with a histamine releasing factor (n = 7). Non-IgE-dependent stimuli (formyl-methionine-leucine-phenylalanine and the ionophore A23187, n = 10) were enhanced less than 5%. rhIL-1-enhancement persisted after cell washing (n = 10). rhIL-1 was active in preparations of 50 to 75% pure basophils in which mononuclear cells were reduced by greater than 95% (n = 4), and mAbH34 to IL-1 beta blocked the enhancement caused by that molecule. We postulate that basophils have an IL-1 receptor which, when occupied, upregulates the response to IgE-related signals. Thus, this work characterizes a second interaction between interleukins and the cells central to the allergic response.

Adjuvants, Immunologic↗
PubMed1989

Regulation of human basophil mediator release by cytokines. I. Interaction with antiinflammatory steroids.

We have analyzed the effects of overnight culture of human basophils with a variety of cytokines in the presence or absence of the glucocorticoid dexamethasone. The 24-h culture of basophils with a range of concentrations of several cytokines (granulocyte-macrophage-CSF, TNF-alpha, IL-1, IL-2, and IL-4) had no effect either on anti-IgE-induced histamine release or the inhibitory effects of dexamethasone on histamine release. IFN-gamma enhanced postculture releasability of human basophils. The concentration range for this effect was from 50 to 50,000 U/ml and maximal enhancement of anti-IgE-induced basophil histamine release was approximately 200% of control. IFN-gamma did not increase the number of occupied or unoccupied Fc epsilon RI on human basophils, suggesting that the enhancement of histamine release is a result of an intrinsic increase in the releasability mechanism. rIL-3 also augmented basophil releasability (approximately 250% of control) by a mechanism independent of alterations in basophil cell surface IgE density. The increase in post culture releasability occurred in both partially purified basophils (12 to 90% purity) and mixed leukocytes (approximately 1% basophils) although it was more marked in the former. Enhanced postculture releasability after exposure to IL-3 occurred for both IgE-dependent (anti-IgE) and peptide-mediated (fmet-leu-phe) responses and included elevations in the release of both histamine and sulfidopeptide leukotriene, suggesting a global increase in releasability. Basophils cultured in the presence of IL-3 were insensitive to the inhibitory effects of dexamethasone; at 1,000 U/ml IL-3, dexamethasone inhibition of basophil mediator release was completely blocked. None of the other cytokines tested, with the exception of crude or partially purified IL-2 preparations, had this effect. IL-3 contamination may explain the ability of these partially purified "IL-2" preparations to block the inhibitory effects of dexamethasone, because this effect was abolished by a specific anti-IL-3 antibody. These results suggest that IFN-gamma and IL-3 may modulate the response of human basophils in allergic reactions. Furthermore, increased local production of IL-3 may "prime" basophils for increased releasability and override inhibitory effects of elevated systemic glucocorticoids on human basophils. Finally, we conclude that the effects of glucocorticoids on human basophils may be in part mediated indirectly by effects on cells which produce cytokines, such as IFN-gamma and IL-3, that can modulate basophil function.

Anti-Inflammatory Agents↗
PubMed1989

Interleukin-1 stimulates proliferation of acute myeloblastic leukemia cells by induction of granulocyte-macrophage colony-stimulating factor release.

In this study, we further established the role of interleukin-1 (IL-1) alpha and IL-1 beta as regulators of proliferation of acute myeloid leukemia (AML) cells. IL-1 stimulated tritiated thymidine (3H-TdR) uptake of AML cells in 13 of 28 cases. Cytogenetic analysis confirmed the leukemic clonality of the IL-1-stimulated cells. Most likely, IL-1 exerted these stimulative effects directly on AML blast cells because IL-1 effectively induced 3H-TdR uptake of CD34-positive AML blasts (separated following cell sorting). Furthermore, adherent cell-depleted AML samples of three patients were more effectively stimulated than nondepleted AML fractions. Cluster and colony formation from adherent cell depleted AML samples could also be stimulated with IL-1, ie, in seven of ten cases analyzed. Subsequent experiments indicated that IL-1 stimulation depended on the release of GM-CSF because (1) induction of DNA synthesis of AML cells by IL-1 could be abrogated with antigranulocyte-macrophage colony-stimulating factor (GM-CSF) antibody, (2) conditioned media (CM) prepared from IL-1 stimulated AML blasts (adherent cell depleted) could stimulate the proliferation of purified normal bone marrow progenitors whereas supernatants from nonstimulated AML blasts did not, and (3) GM-CSF was demonstrated in IL-1/AML-CM with a specific radioimmunoassay, while GM-CSF was not detectable in nonstimulated supernatants. In one case of AML showing significant 3H-TdR uptake in the absence of CSFs, this spontaneous DNA synthesis was found to depend on autocrine IL-1 beta release as it could be suppressed with anti-IL-1 beta antibody or anti-GM-CSF. The blockade by anti-IL-1 beta could be overcome by the addition of high concentrations of IL-1 beta as well as GM-CSF. Thus, in this particular case, endogenously produced IL-1 beta had stimulated the release of GM-CSF which resulted in GM-CSF-dependent proliferation. The results indicate that GM-CSF production by AML blasts is often regulated by IL-1 rather than being constitutive.

Cell Division↗
PubMed1989

Isolation of murine fetal thymus cell lines after infection with recombinant retroviruses containing the v-myc and v-Ha-ras oncogenes.

The mechanisms that regulate thymocyte proliferation and differentiation within the thymus are still poorly understood. As a novel approach to analyzing these problems, we have used a retroviral vector to insert oncogenes into fetal thymic cells, and construct a library of thymic cell lines. Infection with a double promoter recombinant retrovirus containing the v-Ha-ras and v-myc oncogenes resulted in the apparent immortalization of a range of cell lines derived from 13- and 14-day murine fetal thymus, and expressing both v-Ha-ras and v-myc mRNA at high levels. Cell lines were established from untreated thymic lobes (group 1), deoxyguanosine-treated lobes (group 2), and in the presence of IL-2 (group 3). Cell lines with a wide range of surface phenotypes were established. Group 1 were adherent cell lines expressing many antigens, including Mac-1, FcR, and Ia. Group 2 were also adherent cells but expressed very few Ag. Group 3 were IL-2-dependent lymphoid-like non-adherent cells, with a null or early thymocyte-like phenotype. None demonstrated full rearrangement and expression of TCR alpha-, beta-, or gamma-genes, although cell lines in group 2 expressed short beta and those in group 3, short beta and gamma gene transcripts. This library of immortalized cell lines appears to represent several types of stromal cell and early thymocyte precursors present in 13- and 14-day fetal thymus. These cell lines should prove invaluable in reconstructing the environment of the intact fetal thymic lobe, to study the cellular interactions that appear to govern thymocyte proliferation, development, and selection of Ag reactivity.

Animals↗
PubMed1989

Normal B cell precursors responsive to recombinant murine IL-7 and inhibition of IL-7 activity by transforming growth factor-beta.

The ability of stromal cells in bone marrow to support B lymphopoiesis may be partially mediated by secretion of biologically active factors. The first cytokine with lymphopoietic activity to be molecularly cloned from stromal cells, IL-7, was originally identified by its growth-promoting activity on long term cultured lymphocytes. We now report that murine rIL-7 is a potent proliferative stimulus for B cell progenitors isolated from fresh bone marrow. Proliferation was initially most obvious among large precursor cells which bear the B lineage associated Ag, Ly5/220 and BP1. A majority of these also contained cytoplasmic Ig mu H chains. Extended culture with IL-7 resulted in a predominance of immature c mu- lymphocytes. No effect by IL-7 was observed on the proliferation of mature lymphocytes. It also did not induce maturation in a number of early B lineage cell lines, or promote the formation of LPS-responsive, clonable B cells from precursors. When incorporated into semisolid agar medium, IL-7 specifically and rapidly induced the formation of pre-B cell colonies in a linear fashion with respect to numbers of cells cultured from either purified B cell progenitor preparations or unfractionated bone marrow. In both liquid and agar culture conditions, the IL-7 proliferative activity was inhibitable by two related forms of transforming growth factor (TGF) beta, TGF-beta 1 and TGF-beta 2. Taken together, these results indicate that IL-7 is a stimulus for replication of normal B lineage cells at an early stage of differentiation, and its activity can be modulated by other cytokines. IL-7 also provides a means of studying the progeny of a single B cell progenitor, and of enumerating clonable pre-B cells in the absence of colony formation by other cell types in bone marrow.

Agar↗
PubMed1989

Recombinant IL-3 induces histamine release from human basophils.

Human rIL-3 induces histamine release from some human basophils, with cells from atopics responding to a greater extent than non-atopic donors. The dose response curves were highly variable. IL-3 was active on purified basophils and the release process was slower and required more calcium than anti-IgE. Removal of surface IgE from basophils rendered them unresponsive to IL-3. The response could be restored by passive sensitization of basophils with IgE+, IgE known to bind histamine-releasing factors, and not IgE-, IgE unreactive with histamine-releasing factors. Thus, IL-3 uncovers IgE heterogeneity. IL-3 does not, however, directly interact with IgE+. Rather, passive sensitization with IgE+ or stimulation of basophils with low concentrations of several secretagogues renders the cells sensitive to IL-3. IL-3 may well play a pro-inflammatory role by potentiating the effects of IgE+ or various secretagogues.

Antibodies, Anti-Idiotypic↗
PubMed1989

Human interleukin 4 regulates the phenotype of lymphocytes generated during mixed lymphocyte culture and inhibits the IL-2-induced development of LAK function in normal and leukaemic cells.

This study examined the immunoregulatory role of recombinant interleukin 4 (IL-4), also known as B-cell stimulating factor 1, on the generation of cytotoxic effector cells from normal and leukaemic human blood mononuclear cells. When tested on cells from normal individuals, the addition of IL-4 to mixed lymphocyte cultures led to a dose-dependent proliferation of T-helper cells (CD3, 4 positive) with a concomitant decrease in phenotypic and functional cytotoxic T cells and natural killer (NK) cells. IL-4 also inhibited the interleukin-2 (IL-2)-induced generation of lymphokine-activated killer (LAK) activity when added at the beginning of mixed lymphocyte culture. When tested on mature leukaemic NK cells, IL-4 also inhibited the ability of IL-2 to induce LAK function using a short-term culture system. These results show that IL-4 acts on both normal and leukaemic cells and suggests that it acts at more than one level during the development of LAK function.

Antigens, Differentiation↗
PubMed1989

Effects of recombinant growth factors on radiation survival of human bone marrow progenitor cells.

The purpose of this study was to evaluate the individual radioprotective effects of 4 distinct purified recombinant human hematopoietic growth factors, namely recombinant human granulocyte-macrophage colony stimulating factor (rGM-CSF), recombinant human granulocyte colony stimulating factor (rG-CSF), recombinant human interleukin 1 (rIL-1), and recombinant human interleukin 2 (rIL-2) on human myeloid (CFU-GM) and erythroid (BFU-E) bone marrow progenitor cells. We demonstrate that (a) preconditioning with rGM-CSF, rG-CSF, or rIL-1 enables CFU-GM to repair sublethal radiation damage and renders CFU-GM less radiosensitive, (b) preconditioning with rGM-CSF or rIL-1 enables BFU-E to repair sublethal radiation damage, and (c) preconditioning with rIL-2 does not increase the radiation survival of CFU-GM or BFU-E. The effects of recombinant growth factors, in particular rGM-CSF, on the radiation damage repair, radiosensitivity, and proliferative activity of bone marrow progenitor cells resulted in a substantial increase in the mean numbers of progenitor cell-derived hematopoietic colonies in irradiated marrow samples. The effects of rGM-CSF on the radiation response of CFU-GM and BFU-E, and the effects of rG-CSF as well as rIL-1 on the radiation response of CFU-GM did not appear to require the presence of T-cells/T-cell precursors, NK-cells, B-cells/B-cell precursors, monocytes, macrophages, MY8 antigen positive non-CFU-GM myeloblasts, promyelocytes, myelocytes, metamyelocytes, granulocytes, or glycophorin A positive erythroid cells since virtually identical results were obtained with unsorted marrow samples or highly purified fluorescence activated cell sorter (FACS) isolated progenitor cell suspensions. To our knowledge, this report represents the first study on recombinant human growth factor-induced modulation of the radiation responses of normal human bone marrow progenitor cells.

Cell Survival↗
PubMed1989

Human interleukin 7: molecular cloning and growth factor activity on human and murine B-lineage cells.

A cDNA encoding biologically active human interleukin 7 was isolated by hybridization with the homologous murine clone. Nucleotide sequence analysis indicated that this cDNA was capable of encoding a protein of 177 amino acids with a signal sequence of 25 amino acids and a calculated mass of 17.4 kDa for the mature protein. Recombinant human interleukin 7 stimulated the proliferation of murine pre-B cells and was active on cells harvested from human bone marrow that are enriched for B-lineage progenitor cells. Analysis of RNA by blot hybridization demonstrated the presence of two size classes of interleukin 7 mRNA in human splenic and thymic tissue.

Amino Acid Sequence↗
PubMed1989

Interleukin 7 is a T-cell growth factor.

Interleukin 7 (IL-7) is a 25-kDa cytokine which was purified and its corresponding cDNA was cloned based upon its ability to stimulate the proliferation of pre-B cells. It has been shown that IL-7 can also function as a costimulator with Con A for the proliferation of T lymphocytes by inducing the production of interleukin 2 (IL-2). We demonstrate here that IL-7 in combination with phorbol 12-myristate 13-acetate can directly drive the proliferation of purified T cells and that this response is not inhibited by cyclosporine A or by antibodies to IL-2 and IL-4. Stimulation of T cells with phorbol myristate acetate and IL-2, IL-4, or IL-7 prepared T cells to respond to any of the three lymphokines. Although T cells activated in vitro by anti-CD3 or allogeneic cells failed to proliferate when challenged with IL-7, T cells primed in vivo to the same stimuli demonstrated a significant proliferative response when restimulated in vitro with IL-7. IL-7 can, therefore, function both as a growth factor for T cells in an IL-2-independent manner and as a competence factor for the induction of lymphokine responsiveness. The ability to induce IL-7 responsiveness via stimulation of the T-cell receptor complex in vivo, but not in vitro, raises the possibility that IL-7 may play a role in T-cell growth and differentiation in vivo.

Animals↗
PubMed1989

In vitro effects of recombinant interleukin 7 on growth and differentiation of bone marrow pro-B- and pro-T-lymphocyte clones and fetal thymocyte clones.

We have studied the effects of recombinant (r) interleukin 7 (IL-7) on growth and differentiation of marrow pro-B-lymphocyte clones (CB/Bm7, LyD9, LyB9), marrow pro-T-lymphocyte clones (C4-77/3, C4-86/18, C4-95/16), and fetal thymocyte clones (FTH5, FTA2, FTD5) in the presence or absence of the bone marrow stroma clone RP.0.10, which was selected for its ability to promote differentiation of the pro-B clones. rIL-7 alone stimulated some DNA synthesis (measured by [3H]thymidine uptake) but not actual growth (increase in cell number) of the pro-B clones. Antibodies against IL-4 and IL-6 or against receptors for IL-2, IL-3, and IL-5 did not inhibit this effect of rIL-7 on the pro-B clones. rIL-7 alone or in various combinations with other cytokines (from rIL-1 alpha to rIL-6) could not induce differentiation of the pro-B clones into IgM+ B cells regardless of the presence of lipopolysaccharide (LPS). The RP.0.10 marrow stroma cells by themselves do not support the growth of the pro-B clones. However, the pro-B clones grew when cultured with rIL-7 and monolayers of the RP.0.10 stroma cells. While the RP.0.10 stroma cells induced the pro-B clones to differentiate into IgM+ B cells but not T3+ T cells when cultured in the presence of LPS and rIL-3, the B-cell progenitor clones gave rise to significantly higher numbers of IgM+ B cells (up to 63%) and to many more B cells expressing higher levels of surface IgM when cocultured with rIL-7, LPS, and RP.0.10 stroma cells. The pro-B clones also generated IgM+ B cells (up to 20%) when cocultured with RP.0.10 stroma cells and rIL-7 in the absence of LPS. By using culture plates designed for testing requirements for cell-cell contact, we found that cell interactions between the pro-B cell and the marrow stroma cell are essential to induce rearrangement and expression of the immunoglobulin genes in the pro-B clones. Possible mechanisms to account for the remarkable effects of rIL-7 in the presence of RP.0.10 stroma cells on both growth and differentiation of the pro-B clones are discussed. Finally, rIL-7 alone or together with RP.0.10 stroma cells neither supported proliferation nor induced differentiation into T3+ T cells or IgM+ B cells of the marrow pro-T clones or the fetal thymocyte clones. In light of these findings, we postulate that the interaction of the pluripotential stem cell with marrow stroma cells like RP.0.10 and the availability of IL-7 could play a critical role in the commitment to develop along the B-lymphocyte pathway.

Animals↗
PubMed1989

Human interleukin 3: effects on normal and leukemic cells.

The effects of recombinant human interleukin 3 (IL3) on normal bone marrow cells and human leukemic cells were studied. In clonal assays, IL3 supported the growth of all colony types including megakaryocytes. Erythroid colonies were formed in the presence of IL3 and erythropoietin, but not in the absence of erythropoietin. Replating experiments using blast cell colonies derived from a cell population enriched for progenitor cells by fluorescence-activated cell sorting with the monoclonal antibody 3C5, showed that IL3 supported the continued replating of colonies. The clonal proliferation of human bone marrow cells in response to IL3 was inhibited by tumor necrosis factor and by lymphotoxin, but not by interferon-gamma. In suspension cultures, IL3 supported the proliferation of mast cells. Human IL3 had no effect on the growth responses, morphology, cytochemistry, or clonogenicity of the human leukemic cell lines HL60, U-937, KG1a, and HEL. Transcripts for IL3 mRNA were not detectable in these cells, nor in the K562 cell line, implying that autocrine secretion of IL3 was not the mechanism by which these leukemias were maintained. Although cells derived from the bone marrow or peripheral blood of twenty patients with myeloproliferative disorders, myelodysplastic syndromes or acute myeloid leukemia frequently showed proliferative responses to IL3, mRNA transcripts for IL3 were not detected in these cells.

Blood Cells↗
PubMed1989

Regulation of resting and cycling human B lymphocytes via surface IgM and the accessory molecules interleukin-4, CD23 and CD40.

Experiments were designed in order to compare directly the ability of a new and potent monoclonal anti-mu chain antibody to initiate or maintain stimulation in resting and cycling B lymphocytes, respectively. Resting B cells could be stimulated by soluble anti-mu only in the presence of additional signals; these could be supplied by a high dose of phorbol ester or a combination of interleukin-4 (IL-4) and the CD40 antibody, G28-5. Immobilization of anti-mu not only increased the magnitude of the resting B-cell response but also diminished the co-factor requirements. The 'background' stimulation obtained when using a high concentration of immobilized anti-mu was unexpectedly reduced in the presence of IL-4 alone. The duration, but not the magnitude, of the IL-4 signal required for promoting optimal responses varied with the co-stimulation applied. Importantly, the threshold concentrations of soluble anti-mu needed to trigger the resting B cells were reduced upon the addition of each co-stimulant. With actively cycling B cells, both soluble and immobilized anti-mu were now capable of sustaining stimulation which could be prolonged on the addition of IL-4 and/or G28-5. In both resting and cycling populations, a strong correlation was noted between the magnitude of stimulation elicited when IL-4 was present and the release of the soluble CD23 molecule. Moreover, IL-4-promoted, but not other, stimulations could be augmented up to 10-fold by the inclusion of the CD23 antibody MHM6. Both the resting and cycling B-cell populations were found to secrete IgM in direct response to IL-4 and G28-5; this factor-driven production of IgM was differentially modulated by soluble and immobilized anti-mu in the two populations.

Antibodies, Monoclonal↗
PubMed1988

Stimulation of myelopoiesis in patients with aplastic anemia by recombinant human granulocyte-macrophage colony-stimulating factor.

Aplastic anemia is a syndrome in which pancytopenia occurs in the presence of hypocellularity of the bone marrow. To assess the biologic activities of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) in aplastic anemia, we gave GM-CSF (60 to 500 micrograms per square meter of body-surface area) to 10 patients with moderate or severe disease, by continuous intravenous infusion daily for two weeks, and repeated the treatment after a two-week rest period. The treatment increased the white-cell count (1.6- to 10-fold) in all patients, primarily because of an increase in the numbers of neutrophils (1.5 to 20-fold), eosinophils (12- to greater than 70-fold), and monocytes (2- to 32-fold). Rates of hydrogen peroxide production in purified granulocyte fractions increased during GM-CSF treatment. Increases in bone marrow cellularity, myeloid precursor cells, and myeloid:erythroid cell ratios accompanied the white-cell response. Despite the in vivo response of the white-cells, the concentration of colony-forming cells remained the same. Measurable concentrations of interleukin-2 (2 to 15 units per milliliter) were found in the serum of 8 patients, and high levels of erythropoietin (81 to 1200 IU per liter) were found in 10 patients. The predominant side effects were constitutional symptoms. These results indicate that recombinant human GM-CSF is effective in stimulating myelopoiesis in patients with severe aplastic anemia and may benefit some patients in whom the disorder is refractory to standard forms of therapy.

Adolescent↗
PubMed1988

Synergistic effects of purified recombinant human and murine B cell growth factor-1/IL-4 on colony formation in vitro by hematopoietic progenitor cells. Multiple actions.

Purified recombinant human B cell growth factor-1/IL-4 was evaluated, alone and in combination, with purified preparations of recombinant human (rhu) CSF or erythropoietin (Epo) for effects on colony formation by human bone marrow CFU-GM progenitor cells (GM) and burst forming unit-E progenitor cells. rhu IL-4 synergized with rhu G-CSF to enhance granulocyte colony formation, but had no effect on CFU-GM colony formation stimulated by rhu GM-CSF, rhu IL-3, or rhu CSF-1. Rhu IL-4 synergized with Epo to enhance BFU-E colony formation equal to that of Epo plus either rhu IL-3, rhu GM-CSF, or rhu G-CSF. Removal of adherent cells and T lymphocytes did not influence the synergistic activities of rhu IL-4. Rmu IL-4, synergized with rhu G-CSF, but not with rmu GM-CSF, rmu IL-3, or natural mu CSF-1, to enhance CFU-GM (mainly granulocyte) colony numbers by a greater than 90% pure preparation of murine CFU-GM. Also, rhu IL-4 at low concentrations enhanced release of CSF and at higher concentrations the release also of suppressor molecules from human monocytes and PHA-stimulated human T lymphocytes. Use of specific CSF antibodies suggested that rhu IL-4 was enhancing the release of G-CSF and CSF-1 from monocytes and the release of GM-CSF and possibly G-CSF from PHA-stimulated T lymphocytes. Use of antibodies for TNF-alpha, IFN-gamma, or TNF-beta as well as measurement of TNF and IFN titers suggested that the suppressor molecule(s) released from monocytes were acting with TNF-alpha and those released from PHA-stimulated T lymphocytes were acting with IFN-gamma. These results implicate B cell growth factor-1/IL-4 as a synergistic activity for hematopoietic progenitors and suggest that the actions can be on both progenitor and accessory cells.

Animals↗