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G Dranoff

Publications and source records attributed to G Dranoff.

At least 37 records · Page 2Linked to original sources
PubMed1998

Role for interleukin-3 in mast-cell and basophil development and in immunity to parasites.

The cytokine interleukin-3 (IL-3), which can be derived from T cells and other sources, is a potentially important link between the immune and haematopoietic systems. IL-3 may be particularly critical for the development, survival and function of tissue mast cells and blood basophils, which are thought to be important effector cells in immunity to parasites and other immunological responses, such as allergic reactions. Here we show, using IL-3-deficient mice, that IL-3 is not essential for the generation of mast cells or basophils under physiological conditions, but that it does contribute to increased numbers of tissue mast cells, enhanced basophil production, and immunity in mice infected with the nematode Stronglyoides venezuelensis. Parasite expulsion and mast-cell development are impaired even more severely in IL-3-deficient mice that also show a marked reduction in signalling by c-kit. These findings establish a role for IL-3 in immunity to parasites and indicate that one of the functions of IL-3 in host defence against infection is to expand populations of haematopoietic effector cells.

Animals↗
PubMed1998

Involvement of interleukin-3 in delayed-type hypersensitivity.

The in vivo functions of interleukin-3 (IL-3) were investigated by generating IL-3-deficient mice. Although hematopoiesis was unimpaired in homozygous mutant animals, contact hypersensitivity reactions were compromised. IL-3 was required for efficient priming of hapten-specific contact hypersensitivity responses, but was dispensable for T-cell-dependent sensitization to tumor cells. These findings reveal a critical role for IL-3 in some forms of delayed-type hypersensitivity.

Animals↗
PubMed1998

Gene immunotherapy in murine acute myeloid leukemia: granulocyte-macrophage colony-stimulating factor tumor cell vaccines elicit more potent antitumor immunity compared with B7 family and other cytokine vaccines.

In an attempt to explore novel treatment modalities in acute myeloid leukemia (AML), we studied the role of costimulatory and cytokine gene immunotherapy in murine AML. We have previously shown that leukemic mice can be cured with CD80 transfected leukemic cells (B7. 1-AML vaccine) administered early in the course of the disease and that the failure B7.1-AML vaccines administered late cannot be attributed to immunosuppression induced by tumor growth. CD8+ T cells, which are necessary for tumor rejection, are activated rather than suppressed during the first half of the leukemic course in nonvaccinated mice. In this report, we question whether CD86 (B7.2) or the cytokines granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-4 (IL-4), or tumor necrosis factor-alpha (TNF-alpha) can improve the vaccination potential of AML cells. The choice of cytokines was based on their combined and alone as well ability to direct the differentiation of CD34+ cells into potent antigen-presenting dendritic cells in vitro. Our studies show that (1) mice vaccinated with a leukemogenic number of AML cells engineered to express B7.2 (B7.2-AML) or to secrete GM-CSF, IL-4, or TNF-alpha (GM-, IL-4-, TNF-alpha-AML) do not develop leukemia; (2) GM-AML cells are tumorigenic in sublethally irradiated SJL/J mice but not in Swiss nu/nu mice, indicating that killing of tumor cells is not T-cell-dependent; (3) vaccines with irradiated GM-AML, but not B7.2-, IL-4-, or TNF-alpha-AML cells, can elicit leukemia-specific protective and therapeutic immunity; and (4) in head-to-head comparison experiments, vaccination with irradiated GM-AML is more potent than B7.1-AML, curing 80% and providing 20% prolonged survival of the leukemic mice at week 2, as opposed to cures only up to 1 week with B7.1-AML vaccines. These preclinical data emphasize that GM-CSF gene immunotherapy deserves clinical evaluation in AML.

Acute Disease↗
PubMed1998

CSF-1 regulation of Il6 gene expression by murine macrophages: a pivotal role for GM-CSF.

We test the hypothesis that the monocyte-macrophage colony-stimulating factor (CSF-1 or M-CSF) plays a major role in the inflammatory responses of Mphi by acting as a priming agent that heightens their responsiveness to secondary stimulation by other mediators. We previously reported that CSF-1 induced peritoneal Mphi (PMphi) to transcribe several genes including interleukin-6 (Il6) and granulocyte-macrophage colony-stimulating factor (Csfgm). It was reported that the Il6 and Csfgm genes were individually regulated by different pathways but it was not clear to what extent the two genes interacted during Mphi-mediated inflammatory responses. We now show that CSF-1 induces the release of bioactive GM-CSF from mouse resident PMphi. GM-CSF induces Il6 gene expression and synergizes with CSF-1 to induce the release of large amounts of IL-6. PMphi from C57BL/6J-Csfgm(null) mice were shown to release minimal IL-6 in response to CSF-1 and to express a much reduced response to the highly stimulatory combination of CSF-1 and lipopolysaccharide (LPS). Exogenous recombinant GM-CSF restored the IL-6 response of GM-CSF null PMphi to a great extent but not completely. As controls, three other recombinant proteins were tested but of these only tumor necrosis factor alpha (TNF-alpha) was shown to synergize with both CSF-1 and GM-CSF. Using PMphi from mice deficient in the expression of the Il6 gene, it was shown that they released two- to threefold more GM-CSF in response to CSF-1 than their control counterparts. However, an exogenous supply of recombinant IL-6 had no effect on GM-CSF release. The data indicate that the pathways regulating Il6 gene expression are under the control of a complex network of cytokine interactions involving at least CSF-1, GM-CSF, and TNF-alpha, with the added possibility that IL-6 may exert modulatory activity within this network.

Animals↗
PubMed1998

Cancer gene therapy: connecting basic research with clinical inquiry.

Molecular genetics has spawned an impressive outpouring of insights into the biology of neoplastic transformation and the host-tumor relationship. This deeper understanding of cancer pathogenesis presents a rich opportunity to develop novel therapeutic agents with improved selectivity for cancer cells. One promising approach involves gene therapy, which is the introduction of genetic material into a patient's tissues with the intent to achieve therapeutic benefit. A number of gene transfer systems have been designed that enable the genetic modification of relevant target cells, albeit with varying strengths and limitations. Several strategies to exploit gene transfer as a tool to target specific molecular defects intrinsic to cancer cells, enhance tumor chemosensitivity, and augment tumor immunogenicity are under intensive investigation. A number of these approaches have entered initial clinical testing and already provide intriguing new information about the biology of cancer in patients. In this review, I will highlight the critical issues and controversies that underscore preclinical experiments in cancer gene therapy, discuss some of the preliminary findings from the first wave of clinical trials, and speculate about the prospects that cancer gene therapy will change the way that cancer medicine is practiced.

Clinical Trials as Topic↗
PubMed1998

Genetically modified tumor cell vaccines.

Recent progress in identifying tumor antigens and understanding the host-tumor relationship have catalyzed a dramatic expansion of efforts to develop cancer vaccines. Gene transfer technologies have figured prominently in the design of many of these novel immunization schemes. This article highlights some of the key principles and controversies raised by experiments involving genetically modified tumor vaccines and speculates about future directions for investigators in this field.

Animals↗
PubMed1997

CD40-activated human B cells: an alternative source of highly efficient antigen presenting cells to generate autologous antigen-specific T cells for adoptive immunotherapy.

Multiple clinical trials have shown the efficacy of adoptively transferred allogeneic antigen-specific T cells for the treatment of viral infections and relapsed hematologic malignancies. In contrast, the therapeutic potential of autologous antigen-specific T cells has yet to be established since it has been technically difficult to generate sufficient numbers of these T cells, ex vivo. A major obstacle to the success of this objective derives from our inability to simply and rapidly isolate and/or expand large numbers of highly efficient antigen presenting cells (APCs) for repetitive stimulations of antigen-specific T cells in vitro. We show that autologous CD40-activated B cells represent a readily available source of highly efficient APC that appear to have several important advantages over other APCs for ex vivo T cell expansion including: (a) methodological simplicity necessary to generate continuously large numbers of APCs from just 50 cm3 of peripheral blood without loss of APC function; (b) capacity to induce high peak T cell proliferation and interferon-gamma production without IL-10 production; (c) ease in cryopreservation; and (d) markedly reduced cost. We, therefore, contend that CD40-activated B cells are an alternative source of highly efficient APCs with which to generate antigen-specific T cells ex vivo for autologous adoptive immunotherapy.

3T3 Cells↗
PubMed1997

Protective immunity induced by tumor vaccines requires interaction between CD40 and its ligand, CD154.

Interactions between CD40 and its ligand, CD154 (CD40L, gp39), have been shown to play a central role in the regulation of humoral immunity. Recent evidence suggests that this ligand-receptor pair also plays an important role in the induction of cell-mediated immune responses, including those directed against viral pathogens, intracellular parasites, and alloantigens. The contribution of this ligand-receptor pair to the development of protective immunity against syngeneic tumors was evaluated by blocking the in vivo function of CD154 or by studying tumor resistance in mice genetically deficient in CD40 expression (CD40-/-). In the former case, anti-CD154 monoclonal antibody treatment inhibited the generation of protective immune responses after the administration of three potent tumor vaccines: irradiated MCA 105, MCA 105 admixed with Corynebacterium parvum adjuvant, and irradiated B16 melanoma cells transduced with the gene for granulocyte macrophage colony-stimulating factor. Confirmation of the role of CD40/CD154 interactions in tumor immunity was provided by the overt tumor susceptibility in CD40-deficient mice as compared to that in CD40+/+ mice. In this case, wild-type but not CD40-deficient mice could be readily protected against live TS/A tumor challenge by preimmunization with TS/A admixed with C. parvum. These findings suggest a critical role for CD40/CD154 interactions in the induction of cellular immunity by tumor vaccines and may have important implications for future approaches to cell-based cancer therapies.

Adjuvants, Immunologic↗
PubMed1997

Gene therapy for metastatic brain tumors by vaccination with granulocyte-macrophage colony-stimulating factor-transduced tumor cells.

We have developed an ex vivo gene therapy paradigm for the treatment of brain tumors using granulocyte-macrophage colony-stimulating factor (GM-CSF). Murine B16 melanoma cells were infected with MFG recombinant retrovirus containing the mouse GM-CSF cDNA. Subcutaneous vaccination of syngeneic mice with irradiated GM-CSF-secreting B16 melanoma cells was capable of completely protecting animals against subsequent intracranial B16 tumor inoculation, with up to 5 x 10(3) cells. Histologic evaluation revealed the presence of neutrophils, eosinophils, and lymphocytes, including CD4+, CD8+, and CD45R+ cells, in the intracerebral inoculation site, peaking 4 days after intracranial inoculation. In contrast, nonvaccinated animals or animals vaccinated with irradiated, nontransduced B16 cells succumbed to intracranial tumor within 3 weeks after inoculation. Treatment of established intracranial B16 melanoma tumors with subcutaneous injection of irradiated GM-CSF-secreting B16 cells significantly delayed death, as compared to injection of irradiated nontransduced B16 cells or no treatment. In addition, treatment of established intracerebral GL261 gliomas by vaccination with irradiated GM-CSF-secreting B16 cells mixed with irradiated, transduced, or nontransduced GL261 cells also extended survival. These B16/GL261 co-vaccinations also improved outcome and, in some cases, induced immunological memory that protected survivors from subsequent intracranial challenge with GL261 tumor cells. These findings indicate that peripheral vaccination with irradiated tumor cells in the presence of GM-CSF-producing cells can initiate a potent antitumor immune response against intracranial neoplasms.

Animals↗
PubMed1997

Gene therapy 1996.

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Adenoviridae↗
PubMed1997

Bioactivity of autologous irradiated renal cell carcinoma vaccines generated by ex vivo granulocyte-macrophage colony-stimulating factor gene transfer.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) gene-transduced, irradiated tumor vaccines induce potent, T-cell-mediated antitumor immune responses in preclinical models. We report the initial results of a Phase I trial evaluating this strategy for safety and the induction of immune responses in patients with metastatic renal cell carcinoma (RCC). Patients were treated in a randomized, double-blind dose-escalation study with equivalent doses of autologous, irradiated RCC vaccine cells with or without ex vivo human GM-CSF gene transfer. The replication-defective retroviral vector MFG was used for GM-CSF gene transfer. No dose-limiting toxicities were encountered in 16 fully evaluable patients. GM-CSF gene-transduced vaccines were equivalent in toxicity to nontransduced vaccines up to the feasible limits of autologous tumor vaccine yield. No evidence of autoimmune disease was observed. Biopsies of intradermal sites of injection with GM-CSF gene-transduced vaccines contained distinctive macrophage, dendritic cell, eosinophil, neutrophil, and T-cell infiltrates similar to those observed in preclinical models of efficacy. Histological analysis of delayed-type hypersensitivity responses in patients vaccinated with GM-CSF-transduced vaccines demonstrated an intense eosinophil infiltrate that was not observed in patients who received nontransduced vaccines. An objective partial response was observed in a patient treated with GM-CSF gene-transduced vaccine who displayed the largest delayed-type hypersensitivity conversion. No replication-competent retrovirus was detected in vaccinated patients. This Phase I study demonstrated the feasibility, safety, and bioactivity of an autologous GM-CSF gene-transduced tumor vaccine for RCC patients.

Adult↗
PubMed1997

Cloned dendritic cells can present exogenous antigens on both MHC class I and class II molecules.

Pathways for presenting proteins from the extracellular fluids on MHC class I molecules have been described in macrophages. However, it is uncertain whether similar mechanisms exist in dendritic cells, because conventional preparations of these cells can be contaminated with macrophages. We addressed this issue by transducing granulocyte-macrophage CSF into bone marrow cultures followed by supertransfection with myc and raf oncogenes. These immortalized clones displayed dendritic morphology, and many expressed the dendritic cell-specific markers DEC-205 and 33D1 as well as high levels of MHC molecules and costimulatory molecules. Using these cloned dendritic cells, we found that exogenous OVA could be presented on both their MHC class I and class II molecules. This presentation was markedly enhanced when the Ag was particulate and internalized by phagocytosis. Presentation of particulate OVA on MHC class I molecules was insensitive to the weak base chloroquine, but was blocked by peptide aldehyde inhibitors of the proteasome, indicating that the class I-presented peptides were generated in the cytosol. Brefeldin A, which inhibits the exocytosis of newly synthesized proteins from the endoplasmic reticulum, also inhibited Ag presentation. These results establish that dendritic cells can present exogenous Ags on MHC class I molecules and appear to use a similar phagosome to cytosol pathway as macrophages. Therefore, dendritic cells are likely to play an important role in generating immune responses to tissue transplants and tumors in vivo. Furthermore, these findings provide an approach for targeting vaccine Ags into these cells to prime immune responses in vivo.

Animals↗
PubMed1997

A case report: immune responses and clinical course of the first human use of granulocyte/macrophage-colony-stimulating-factor-transduced autologous melanoma cells for immunotherapy.

The first use of granulocyte/macrophage-colony-stimulating-factor-transduced, lethally irradiated, autologous melanoma cells as a therapeutic vaccine in a patient, with rapidly progressive, widely disseminated malignant melanoma resulted in the generation of a novel antitumour immune response associated with partial, albeit temporary, clinical benefit. An initially negative reaction to non-transduced, autologous melanoma cells was converted to a delayed-type hypersensitivity (DTH) reaction of increasing magnitude following successive vaccinations. While intradermal vaccine sites showed prominent dendritic cell accrual, DTH sites revealed a striking influx of eosinophils in addition to activated/memory T lymphocytes and macrophages, recalling the histology of challenge tumour cell rejection in immune mice. Cytotoxic T lymphocytes (CTL) reactive with autologous melanoma cells were detectable at high frequency after vaccination, not only in limiting-dilution analysis, but also in bulk culture without added cytokines. Clonal analysis of CTL showed a conversion from a purely CD8+ response to a high proportion of CD4+ clones following vaccination. A prominent acute-phase response manifested by a five- to tenfold increase in C-reactive protein was observed, as was a systemic eosinophila. Vaccination resulted in the regression of axillary lymphatic metastases, stabilisation of pulmonary metastases, and a dramatic, reversible increase in cerebral oedema associated with multiple central nervous system metastases: however, lesions in the adrenal glands, pancreas and spleen proved refractory. The antitumour effects and immune response were not detectable 2 months following the last vaccination. Irradiation of the extensive cerebral metastases resulted in rapid deterioration and death of the patient.

Autopsy↗
PubMed1997

Characterization of a spontaneous murine astrocytoma and abrogation of its tumorigenicity by cytokine secretion.

OBJECTIVE: The promise of immunotherapies developed against brain tumors in animal models has not been realized in human clinical trials. This may be because of the routine use of rodent tumors artificially induced by chemicals or viruses that do not accurately portray the intrinsic qualities of spontaneously arising human tumors and that often fail to incorporate the role of immunosuppressants, such as transforming growth factor-beta, that are secreted by human gliomas. From an astrocytoma that arose spontaneously in inbred VM/Dk mice, we have characterized a highly tumorigenic spontaneous murine astrocytoma cell line (SMA-560) that retains features of glial differentiation and naturally produces high levels of biologically active transforming growth factor-beta. We have used this model to determine whether cytokine production by tumor cells will inhibit intracerebral astrocytoma growth. METHODS: Packaging cell lines producing replication-incompetent retroviral vectors were used to transfect the SMA-560 cell line in vitro with the genes encoding the murine cytokines interleukin (IL)-2, IL-3, IL-4, IL-6, tumor necrosis factor-alpha, gamma-interferon, or granulocyte-macrophage colony-stimulating factor or the costimulatory molecule B7.1 (CD80). RESULTS: Mice challenged intracerebrally with 5000 untransfected SMA-560 cells all succumbed to tumor within 30 days, with a median survival of 25 days. In contrast, mice challenged with SMA-560 cells producing IL-2, IL-4, or tumor necrosis factor-alpha each had a more than 400% increase in median survival (P < 0.0001). In these groups, 78.3% (18 of 23 mice), 66.7% (10 of 15 mice), and 60% (6 of 10 mice) of the mice, respectively, remained alive without evidence of tumor for longer than 100 days after the initial tumor challenge. All other cytokines tested and the expression of B7.1 failed to result in an increase in median survival. CONCLUSION: Using a spontaneous astrocytoma model in an inbred mouse strain, we have shown that cytokine production by glial tumors can abrogate their tumorigenicity in vivo despite production of transforming growth factor-beta. These results predict that approaches directed at cytokine production within intracerebral astrocytomas may be efficacious in human trials and that the "immunological privilege" of the brain may not be absolute under such conditions.

Animals↗
PubMed1997

GM-CSF enhances lung growth and causes alveolar type II epithelial cell hyperplasia in transgenic mice.

The human surfactant protein (SP)-C gene promoter was used to direct expression of mouse granulocyte macrophage colony-stimulating factor (GM-CSF; SP-C-GM mice) in lung epithelial cells in GM-CSF-replete (GM+/+) or GM-CSF null mutant (GM-/-) mice. Lung weight and volume were significantly increased in SP-C-GM mice compared with GM+/+ or GM-/- control mice. Immunohistochemical staining demonstrated marked type II cell hyperplasia, and immunofluorescent labeling for proliferating cell nuclear antigen was increased in type II cells of SP-C-GM mice. Abundance of type II cells per mouse lung was increased three- to fourfold in SP-C-GM mice compared with GM+/+ and GM-/- mice. GM-CSF increased bromodeoxyuridine labeling of isolated type II cells in vitro. Type II cells, alveolar macrophages, and endothelial and bronchiolar epithelial cells were stained by antibodies to the GM-CSF receptor alpha-subunit in both GM+/+ mice and GM-CSF gene-targeted mice that are also homozygous for the SP-C-GM transgene. High levels of GM-CSF expression in type II cells of transgenic mice increased lung size and caused type II cell hyperplasia, demonstrating an unexpected role for the molecule in the regulation of type II cell proliferation and differentiation.

Animals↗
PubMed1996

Subcutaneous vaccination with irradiated, cytokine-producing tumor cells stimulates CD8+ cell-mediated immunity against tumors located in the "immunologically privileged" central nervous system.

Vaccination with cytokine-producing tumor cells generates potent immune responses against tumors outside the central nervous system (CNS). The CNS, however, is a barrier to allograft and xenograft rejection, and established tumors within the CNS have failed to respond to other forms of systemic immunotherapy. To determine what barriers the "immunologically privileged" CNS would pose to cytokine-assisted tumor vaccines and what cytokines would be most efficacious against tumors within the CNS, we irradiated B16 murine melanoma cells producing murine interleukin 2 (IL-2), IL-3, IL-4, IL-6, gamma-interferon, or granulocyte-macrophage colony stimulating factor (GM-CSF) and used these cells as subcutaneous vaccines against tumors within the brain. Under conditions where untransfected B16 cells had no effect, cells producing IL-3, IL-6, or GM-CSF increased the survival of mice challenged with viable B16 cells in the brain. Vaccination with B16 cells producing IL-4 or gamma-interferon had no effect, and vaccination with B16 cells producing IL-2 decreased survival time. GM-CSF-producing vaccines were also able to increase survival in mice with pre-established tumors. The response elicited by GM-CSF-producing vaccines was found to be specific to tumor type and to be abrogated by depletion of CD8+ cells. Unlike the immunity generated against subcutaneous tumors by GM-CSF, however, the effector responses generated against tumors in the CNS were not dependent on CD4+ cells. These data suggest that cytokine-producing tumor cells are very potent stimulators of immunity against tumors within the CNS, but effector responses in the CNS may be different from those obtained against subcutaneous tumors.

Animals↗