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Raby GD, Johnson TB, Kessel ST, Stewart TJ, Fisk AT. A field test of the use of pop-off data storage tags in freshwater fishes. J Fish Biol 2017; 91:1623-1641. [PMID: 29023720 DOI: 10.1111/jfb.13476] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 08/24/2017] [Indexed: 06/07/2023]
Abstract
In the present study, pop-off data storage tags (pDST) without any transmitting capabilities were attached to 118 adult salmonids in a 19 000 km2 freshwater system (Lake Ontario). The 9·3 cm long cylindrical tags were externally attached to fishes using a backpack-style harness, set to record pressure (dBar ≈ depth in m) and temperature every 70 s (and at some key times, every 5 s) and programmed to release from the harness and float to the surface after c. 1 year. Recapture of the bright-orange tags for data retrieval relied on members of the public finding tags on shore, or on anglers capturing fishes with tags attached and using the contact information displayed on each tag to mail tags to the research team in exchange for a monetary reward. Thirty-seven tags were found and returned from the 118 released (31%), while 26 of the 118 tags (22%) remained scheduled to pop-off in summer 2017. Of the 37 tags returned, 23 were from wild-caught fishes (out of 88 wild-caught and tagged fishes; 26%) and yielded useful data whereas 14 were from hatchery-reared fishes that were opportunistically tagged and appear to have been unable to acclimate to life in the wild and died days to weeks after release. The field study described here thus demonstrated that pDSTs can be a viable option for collecting large amounts of high-resolution depth and temperature data for salmonids in freshwater systems. Technical challenges, limitations and unknowns related to the use of pDSTs with freshwater fishes are discussed. In addition, pDSTs are compared with alternate electronic tagging technologies and assessed for their potential as a more widespread tool in research on freshwater fishes.
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Affiliation(s)
- G D Raby
- Great Lakes Institute for Environmental Research, University of Windsor, 2601 Union St., Windsor, Ontario N9B 3P4, Canada
| | - T B Johnson
- Glenora Fisheries Station, Ontario Ministry of Natural Resources and Forestry, Picton, Ontario KOK 2T0, Canada
| | - S T Kessel
- Great Lakes Institute for Environmental Research, University of Windsor, 2601 Union St., Windsor, Ontario N9B 3P4, Canada
- Department of Fisheries and Wildlife, Center for Systems Integration and Sustainability, Michigan State University, 1405 South Harrison Road, 115 Manly Miles Building, East Lansing, MI 48823, U.S.A
| | - T J Stewart
- Glenora Fisheries Station, Ontario Ministry of Natural Resources and Forestry, Picton, Ontario KOK 2T0, Canada
| | - A T Fisk
- Great Lakes Institute for Environmental Research, University of Windsor, 2601 Union St., Windsor, Ontario N9B 3P4, Canada
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2
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Stewart TJ, Szlachetko J, Sigg L, Behra R, Nachtegaal M. Tracking the Temporal Dynamics of Intracellular Lead Speciation in a Green Alga. Environ Sci Technol 2015; 49:11176-81. [PMID: 26320742 DOI: 10.1021/acs.est.5b02603] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Organisms have developed metal regulatory mechanisms in response to changes in the bioavailability of trace metals. Just as metal bioavailability dictates cellular uptake, intracellular metal speciation determines the availability of metals to exert biological effects. However, the missing link in understanding the relationship between metal uptake and biological responses is the ability to accurately measure intracellular metal speciation. We conducted Pb exposure studies on the well-characterized model green alga Chlamydomonas reinhardtii and identified temporal changes in intracellular Pb speciation under conditions relevant for fresh water ecosystems using resonant X-ray emission spectroscopy (RXES), which possesses enhanced sensitivity to functional group chemistry relative to X-ray absorption spectroscopy (XAS). Analysis of RXES maps show that only a small fraction of total intracellular Pb was complexed by thiol groups. Initial sequestration of Pb in oxides and inorganic phosphate was followed by binding of Pb to organic phosphate, suggesting potential interference in vital cellular functions. These results contrast proposed detoxification responses involving complexation by thiol groups from peptides.
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Affiliation(s)
- T J Stewart
- Eawag, Swiss Federal Institute of Aquatic Science and Technology , CH-8600 Dübendorf, Switzerland
- ETH , Institute of Biogeochemistry and Pollutant Dynamics IBP, CH-8092 Zurich, Switzerland
| | - J Szlachetko
- Paul Scherrer Institute , 5232 Villigen PSI, Switzerland
- Institute of Physics, Jan Kochanowski University , P-25-406 Kielce, Poland
| | - L Sigg
- Eawag, Swiss Federal Institute of Aquatic Science and Technology , CH-8600 Dübendorf, Switzerland
- ETH , Institute of Biogeochemistry and Pollutant Dynamics IBP, CH-8092 Zurich, Switzerland
| | - R Behra
- Eawag, Swiss Federal Institute of Aquatic Science and Technology , CH-8600 Dübendorf, Switzerland
| | - M Nachtegaal
- Paul Scherrer Institute , 5232 Villigen PSI, Switzerland
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Li M, Knight DA, A Snyder L, Smyth MJ, Stewart TJ. A role for CCL2 in both tumor progression and immunosurveillance. Oncoimmunology 2014; 2:e25474. [PMID: 24073384 PMCID: PMC3782157 DOI: 10.4161/onci.25474] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 06/18/2013] [Accepted: 06/19/2013] [Indexed: 01/27/2023] Open
Abstract
The chemokine CCL2, which is best known for its chemotactic functions, is expressed not only by immune cells, but also by several types of malignant and stromal cells. CCL2 has been shown to exert both pro- and anti-tumor effects. However, recent results demonstrate a main role for CCL2 in tumor progression and metastasis, suggesting that this chemokine may constitute a therapeutic target for anticancer drugs. Mammary carcinoma models, including models of implantable, transgenic, and chemically-induced tumors, were employed in the setting of Ccl2 or Ccr2 knockout mice or CCL2 neutralization with a monoclonal antibody to further investigate the role of the CCL2/CCR2 signaling axis in tumor progression and metastatic spread. In our implantable tumor models, an anti-CCL2 monoclonal antibody inhibited the growth of primary malignant lesions in a biphasic manner and reduced the number of metastases. However, in Ccl2-/- or Ccr2-/- mice developing implanted or transgenic tumors, the number of pulmonary metastases was increased despite a reduction in the growth rate of primary neoplasms. Transgenic Mtag.Ccl2-/- or Mtag.Ccr2-/- mice also exhibited a significantly earlier of disease onset. In a chemical carcinogenesis model, anti-CCL2 monoclonal antibody inhibited the growth of established lesions but was ineffective in the tumor induction phase. In contrast to previous studies indicating a role for CCL2 in the establishment of metastases, we have demonstrated that the absence of CCL2/CCR2-signaling results in increased metastatic disease. Thus, the CCL2/CCR2 signaling axis appears to play a dual role in mediating early tumor immunosurveillance and sustaining the growth and progression of established neoplasms. Our findings support the use of anti-CCL2 therapies for the treatment of established breast carcinoma, although the complete abrogation of the CCL2 signaling cascade may also limit immunosurveillance and support metastatic spread.
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Affiliation(s)
- Ming Li
- Cancer Immunology Program; Peter MacCallum Cancer Centre; East Melbourne, VIC Australia ; Sir Peter MacCallum Department of Oncology; The University of Melbourne; East Melbourne, VIC Australia
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Verbrugge I, Gasparini A, Haynes NM, Hagekyriakou J, Galli M, Stewart TJ, Abrams SI, Yagita H, Verheij M, Johnstone RW, Borst J, Neefjes J. The Curative Outcome of Radioimmunotherapy in a Mouse Breast Cancer Model Relies on mTOR Signaling. Radiat Res 2014; 182:219-29. [DOI: 10.1667/rr13511.1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Inge Verbrugge
- Division of Immunology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Alessia Gasparini
- Division of Radiotherapy, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Nicole M. Haynes
- Cancer Therapeutics Program, Peter MacCallum Cancer Centre, East Melbourne, Australia
| | - Jim Hagekyriakou
- Department of Physical Chemistry, Peter MacCallum Cancer Centre, East Melbourne, Australia
| | - Mara Galli
- Cancer Therapeutics Program, Peter MacCallum Cancer Centre, East Melbourne, Australia
| | - Trina J. Stewart
- Griffith Health Institute, School of Medical Sciences, Griffith University, Gold Coast, Australia
| | - Scott I. Abrams
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, New York
| | - Hideo Yagita
- Department of Immunology, Juntendo University School of Medicine, Tokyo, Japan; and
| | - Marcel Verheij
- Division of Radiotherapy, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Ricky W. Johnstone
- Cancer Therapeutics Program, Peter MacCallum Cancer Centre, East Melbourne, Australia
| | - Jannie Borst
- Division of Immunology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Jacques Neefjes
- Division of Cell Biology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
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Li M, Knight DA, Smyth MJ, Stewart TJ. Sensitivity of a novel model of mammary cancer stem cell-like cells to TNF-related death pathways. Cancer Immunol Immunother 2012; 61:1255-68. [PMID: 22270714 PMCID: PMC11029674 DOI: 10.1007/s00262-012-1200-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 01/05/2012] [Indexed: 01/05/2023]
Abstract
Cancer stem cells (CSC) are resistant to radiation and chemotherapy and play a significant role in cancer recurrence and metastatic disease. It is therefore important to identify alternative strategies, such as immunotherapies that can be used to control this refractory population. A CD44(+)CD24(-/low) subpopulation of cells within the B6 PyMT-MMTV transgenic mouse-derived AT-3 mammary carcinoma cell line was identified, which had CSC-like characteristics, including pluripotency and a resistance to chemo- and radiotherapy. Therefore, unlike xenograph models that require immunocompromised settings, this novel system may provide a means to study immune-mediated responses against CSC-like cells. The immunobiology of the AT-3 CSC-like cell population was studied by their surface molecule expression profile and their sensitivity to specified cell death pathways. Comparable levels of Rae-1, CD155, CD54 and higher levels of Fas and DR5 were expressed on the AT-3 CSC-like cells compared to non-CSC-like tumor cells. Expression correlated with an in vitro sensitivity to cell death by NK cells or through the ligation of the death receptors (Fas or DR5), by their ligands or anti-Fas and anti-DR5 mAbs. Indeed, compared to the rest of the AT-3 tumor cells, the CD44(+)CD24(-/low) subpopulation of cells were more sensitive to both Fas- and TRAIL-mediated cell death pathways. Therefore, despite the refractory nature of CSC to other conventional therapies, these CSC-like cells were not inherently resistant to specified forms of immune-mediated cell death. These results encourage the continued investigation into immunotherapeutic strategies as a means of controlling breast CSC, particularly through their cell death pathways.
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Affiliation(s)
- Ming Li
- Cancer Immunology Research Program, Peter MacCallum Cancer Centre, Locked Bag#1, A’Beckett Street, Melbourne, VIC 8006 Australia
| | - Deborah A. Knight
- Cancer Immunology Research Program, Peter MacCallum Cancer Centre, Locked Bag#1, A’Beckett Street, Melbourne, VIC 8006 Australia
| | - Mark J. Smyth
- Cancer Immunology Research Program, Peter MacCallum Cancer Centre, Locked Bag#1, A’Beckett Street, Melbourne, VIC 8006 Australia
| | - Trina J. Stewart
- Cancer Immunology Research Program, Peter MacCallum Cancer Centre, Locked Bag#1, A’Beckett Street, Melbourne, VIC 8006 Australia
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Stewart TJ, Greeneltch KM, Reid JE, Liewehr DJ, Steinberg SM, Liu K, Abrams SI. Interferon regulatory factor-8 modulates the development of tumour-induced CD11b+Gr-1+ myeloid cells. J Cell Mol Med 2011; 13:3939-50. [PMID: 20196788 PMCID: PMC3858838 DOI: 10.1111/j.1582-4934.2009.00685.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Tumour-induced myeloid-derived suppressor cells (MDSC) promote immune suppression and mediate tumour progression. However, the molecular basis for the generation of MDSC, which in mice co-express the CD11b+ and Gr-1+ cell surface markers remains unclear. Because CD11b+Gr-1+ cells expand during progressive tumour growth, this suggests that tumour-induced events alter signalling pathways that affect normal myeloid cell development. Interferon regulatory factor-8 (IRF-8), a member of the IFN-γ regulatory factor family, is essential for normal myelopoiesis. We therefore examined whether IRF-8 modulated tumour-induced CD11b+Gr-1+ cell development or accumulation using both implantable (4T1) and transgenic (MMTV-PyMT) mouse models of mammary tumour growth. In the 4T1 model, both splenic and bone marrow-derived CD11b+Gr-1+ cells of tumour-bearing mice displayed a marked reduction in IRF-8 expression compared to control populations. A causal link between IRF-8 expression and the emergence of tumour-induced CD11b+Gr-1+ cells was explored in vivo using a double transgenic (dTg) mouse model designed to express transgenes for both IRF-8 and mammary carcinoma development. Despite the fact that tumour growth was unaffected, splenomegaly, as well as the frequencies and absolute numbers of CD11b+Gr-1+ cells were significantly lower in dTg mice when compared with single transgenic tumour-bearing mice. Overall, these data reveal that IRF-8 plays an important role in tumour-induced development and/or accumulation of CD11b+Gr-1+ cells, and establishes a molecular basis for the potential manipulation of these myeloid populations for cancer therapy.
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Affiliation(s)
- Trina J Stewart
- Laboratory of Tumor Immunology and Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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7
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Stewart TJ, Liewehr DJ, Steinberg SM, Greeneltch KM, Abrams SI. Modulating the expression of IFN regulatory factor 8 alters the protumorigenic behavior of CD11b+Gr-1+ myeloid cells. J Immunol 2009; 183:117-28. [PMID: 19542426 PMCID: PMC2744444 DOI: 10.4049/jimmunol.0804132] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
CD11b(+)Gr-1(+)-expressing cells, termed myeloid-derived suppressor cells, can mediate immunosuppression and tumor progression. However, the intrinsic molecular events that drive their protumorigenic behavior remain to be elucidated. Although CD11b(+)Gr-1(+) cells exist at low frequencies in normal mice, it also remains unresolved whether they are biologically distinct from those of tumor-bearing hosts. These objectives were investigated using CD11b(+)Gr-1(+) cells from both implantable (4T1) and autochthonous (mouse mammary tumor virus-polyomavirus middle T Ag (MMTV-PyMT)) mouse models of mammary carcinoma. Limited variation was observed in the expression of markers associated with immunoregulation between CD11b(+)Gr-1(+) cells of both tumor models, as well as with their respective controls (Cnt). Despite limited differences in phenotype, tumor-induced CD11b(+)Gr-1(+) cells were found to produce a more immunosuppressive cytokine profile than that observed by Cnt CD11b(+)Gr-1(+) cells. Furthermore, when admixed with tumor cells, CD11b(+)Gr-1(+) cells from tumor-bearing mice significantly enhanced neoplastic growth compared with counterpart cells from Cnt mice. However, the protumorigenic behavior of these tumor-induced CD11b(+)Gr-1(+) cells was significantly diminished when the expression of IFN regulatory factor 8, a key myeloid-associated transcription factor, was enhanced. The loss of this protumorigenic effect occurred independently of the host immune system and correlated with a CD11b(+)Gr-1(+) cytokine/chemokine production pattern that resembled cells from nontumor-bearing Cnt mice. Overall, our data indicate that 1) tumor-induced CD11b(+)Gr-1(+) cells from both cancer models were phenotypically similar, but biologically distinct from their nontumor-bearing counterparts and 2) modulation of IFN regulatory factor 8 levels in tumor-induced CD11b(+)Gr-1(+) cells can significantly abrogate their protumorigenic behavior, which may have important implications for cancer therapy.
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MESH Headings
- Animals
- Biomarkers, Tumor/biosynthesis
- Biomarkers, Tumor/genetics
- CD11b Antigen/biosynthesis
- Cell Line, Tumor
- Cell Movement/genetics
- Cell Movement/immunology
- Cell Proliferation
- Female
- Gene Expression Regulation, Leukemic/immunology
- Gene Expression Regulation, Neoplastic/immunology
- Interferon Regulatory Factors/biosynthesis
- Interferon Regulatory Factors/genetics
- Interferon Regulatory Factors/physiology
- Male
- Mammary Neoplasms, Experimental/genetics
- Mammary Neoplasms, Experimental/immunology
- Mammary Neoplasms, Experimental/pathology
- Mammary Neoplasms, Experimental/therapy
- Mammary Tumor Virus, Mouse/genetics
- Mammary Tumor Virus, Mouse/immunology
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Nude
- Mice, Transgenic
- Myeloid Cells/immunology
- Myeloid Cells/metabolism
- Myeloid Cells/pathology
- Polyomavirus/genetics
- Polyomavirus/immunology
- Receptors, Chemokine/biosynthesis
- Up-Regulation/genetics
- Up-Regulation/immunology
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Affiliation(s)
- Trina J. Stewart
- Laboratory of Tumor Immunology and Biology, National Cancer Institute, National Institutes of Health, 10 Center Drive, Rm. 5B46, Bethesda, MD 20892
| | - David J. Liewehr
- Biostatistics and Data Management Section, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Seth M. Steinberg
- Biostatistics and Data Management Section, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Kristy M. Greeneltch
- Laboratory of Tumor Immunology and Biology, National Cancer Institute, National Institutes of Health, 10 Center Drive, Rm. 5B46, Bethesda, MD 20892
| | - Scott I. Abrams
- Laboratory of Tumor Immunology and Biology, National Cancer Institute, National Institutes of Health, 10 Center Drive, Rm. 5B46, Bethesda, MD 20892
- Department of Immunology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263
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Stewart TJ, Christine Lutsiak ME, Abrams SI. Immune Consequences of Protracted Host-Tumor Interactions in a Transgenic Mouse Model of Mammary Carcinoma. Cancer Invest 2009; 26:237-49. [DOI: 10.1080/07357900701708419] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Abstract
A surge in interest in the chemokine–chemokine receptor network is probably related to the expanding roles that chemokines have now been identified to play in human biology, particularly immunity. Specific tissue microenvironments express distinct chemokines and both hematopoietic and nonhematopoietic cells have receptor expression profiles that permit the coordinated trafficking and organization of cells within these specific tissues. Since the chemokine network plays critical roles in both the function of the immune system and the progression of cancer, it is an attractive target for therapeutic manipulation. This review will focus on chemokine and chemokine receptor network-related therapeutic interventions that utilize host–tumor interactions particularly involving the immune system.
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Affiliation(s)
- Trina J Stewart
- Cancer Immunology Research Program, The Peter MacCallum Cancer Centre, Level 2 Smorgon Family Building, St Andrews Place, East Melbourne, Victoria, 3002, Australia
| | - Mark J Smyth
- Cancer Immunology Research Program, The Peter MacCallum Cancer Centre, Level 2 Smorgon Family Building, St Andrews Place, East Melbourne, Victoria, 3002, Australia
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Yang D, Stewart TJ, Smith KK, Georgi D, Abrams SI, Liu K. Downregulation of IFN-gammaR in association with loss of Fas function is linked to tumor progression. Int J Cancer 2008; 122:350-62. [PMID: 17918178 DOI: 10.1002/ijc.23090] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The host immune system functions as an intrinsic surveillance network in the recognition and destruction of tumor cells, and it has been demonstrated that lymphocytes and IFN-gamma are the primary tumor suppressors of the immune system. However, the immune system can concurrently select for tumor variants with reduced immunogenicity and aggressive phenotypes. We report here that tumor escape variants that have survived CTL adoptive immunotherapy exhibited decreased expression levels of both Fas and IFN-gammaR in vitro. Furthermore, examination of spontaneously arising mouse primary mammary carcinoma and lung metastases revealed that both Fas and IFN-gammaR protein levels were dramatically lower in lung metastases than in primary tumors in vivo. Functional disruption of either the Fas- or the IFN-gamma signaling pathway enhanced the colonization efficiency of preexisting metastatic tumor cells, whereas disruption of both Fas and IFN-gammaR pathways resulted in synergistic augmentation of the colonization efficiency of the preexisting metastatic tumor cells, as determined by experimental lung metastases assay. Gene expression profiling revealed that altered expression of genes involved in immediate IFN-gammaR signaling, the interferon primary response, apoptosis and tumor colonization is associated with loss of IFN-gammaR function and enhanced metastatic potential. Interestingly, disruption of IFN-gammaR function did not alter tumor cell susceptibility to CTL-mediated cytotoxicity, but is linked to enhanced infiltration of endogenous T cells in the tumor microenvironment in vivo. These findings suggest that coordinate downregulation of Fas and IFN-gammaR, 2 key components of cancer immunosurveillance system on tumor cells, leads to a more aggressive metastatic phenotype.
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Affiliation(s)
- Dafeng Yang
- Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta, GA 30912, USA
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Stewart TJ, Abrams SI. Altered immune function during long-term host-tumor interactions can be modulated to retard autochthonous neoplastic growth. J Immunol 2007; 179:2851-9. [PMID: 17709499 DOI: 10.4049/jimmunol.179.5.2851] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Ag-specific and generalized forms of immunosuppression have been documented in animal tumor models. However, much of our knowledge on tumor-induced immunosuppression was acquired using tumor implant models, which do not reiterate the protracted nature of host-tumor interactions. Therefore, a transgenic mouse model of autochthonous mammary tumor development and progression was chosen to investigate the long-term consequences of neoplastic growth on the immune system. In vitro proliferation of unfractionated splenocytes from tumor-bearing mice, as assessed by [(3)H]thymidine uptake, was inhibited by the presence of suppressor cells within these splenocyte preparations, because purifying the T cells restored their biological activity. However, the level of inhibition did not correlate with either tumor load or the percentage of myeloid-derived CD11b+Gr1+ cells. To evaluate tumor-specific immune dysfunction, transgenic mice were challenged with autologous tumor cells. Mice with extensive, but not minimal autochthonous tumor burdens demonstrated a significantly enhanced rate of autologous tumor growth compared with age-matched controls. In contrast, an allogeneic tumor challenge was efficiently rejected from both groups of transgenic mice. It was also noted that allogeneic tumor challenge of mice with minimal disease significantly inhibited autochthonous primary tumor growth. We therefore demonstrated that 1) a generalized form of immunosuppression occurred, but not as a result of permanent alterations to T cell function, because purified T cell subsets retained normal biological activity following polyclonal or allostimulation; and 2) tumor-specific immunosuppression emerged as a consequence of tumor progression, but could be modulated to enhance antitumor responses against autochthonous primary neoplastic growth.
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Affiliation(s)
- Trina J Stewart
- Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, 10 Center Drive, Bethesda, MD 20892, USA
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13
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Greeneltch KM, Schneider M, Steinberg SM, Liewehr DJ, Stewart TJ, Liu K, Abrams SI. Host Immunosurveillance Controls Tumor Growth via IFN Regulatory Factor-8–Dependent Mechanisms. Cancer Res 2007; 67:10406-16. [DOI: 10.1158/0008-5472.can-07-1228] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Stewart TJ, Greeneltch KM, Lutsiak MEC, Abrams SI. Immunological responses can have both pro- and antitumour effects: implications for immunotherapy. Expert Rev Mol Med 2007; 9:1-20. [PMID: 17284328 DOI: 10.1017/s1462399407000233] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Immune responses influence the development and progression of a malignancy. The tumour can also manipulate the immune system to its own ends, often resulting in an ineffective or transient antitumour response. An appreciation of the complexity of these host-tumour interactions is therefore important for the development of more-effective cancer therapies. This article highlights some prominent mechanisms whereby tumours escape recognition and destruction by the host immune system, thus facilitating disease progression. One important consequence of tumour escape is that an antitumour immune response may unintentionally lead to the outgrowth of less immunogenic or more apoptosis-resistant tumour escape variants, which possess enhanced tumourigenic potential. Insights into the molecular mechanisms of cancer evasion and the complexity of the ever-changing interactions between host and tumour will enable a more rational design of antitumour therapies and may help not only explain disease recurrence, but also identify potential targets for therapeutic interventions. This article also offers a brief review of preclinical animal models, which are essential tools in the study of tumour immunology and cancer biology, particularly those that recapitulate the chronic nature of host-tumour interactions and help guide the development and testing of new therapies.
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Affiliation(s)
- Trina J Stewart
- Tumor Immunobiology Group, Laboratory of Tumor Immunology and Biology, National Cancer Institute, Bethesda, MD 20892, USA
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15
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Abstract
Immunotherapy of tumours using T cells expanded in vitro has met with mixed clinical success suggesting that a greater understanding of tumour/T-cell interaction is required. We used a HPV16E7 oncoprotein-based mouse tumour model to study this further. In this study, we demonstrate that a HPV16E7 tumour passes through at least three stages of immune susceptibility over time. At the earliest time point, infusion of intravenous immune cells fails to control tumour growth although the same cells given subcutaneously at the tumour site are effective. In a second stage, the tumour becomes resistant to subcutaneous infusion of cells but is now susceptible to both adjuvant activated and HPV16E7-specific immune cells transferred intravenously. In the last phase, the tumour is susceptible to intravenous transfer of HPV16E7-specific cells, but not adjuvant-activated immune cells. The requirement for IFN-gamma and perforin also changes with each stage of tumour development. Our data suggest that effective adoptive T-cell therapy of tumour will need to be matched with the stage of tumour development.
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Affiliation(s)
- Trina J Stewart
- Centre for Immunology and Cancer Research, Princess Alexandra Hospital, University of Queensland, Woolloongabba, Brisbane, QLD 4102, Australia
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Stewart TJ, Drane D, Malliaros J, Elmer H, Malcolm KM, Cox JC, Edwards SJ, Frazer IH, Fernando GJP. ISCOMATRIX™ adjuvant: an adjuvant suitable for use in anticancer vaccines. Vaccine 2004; 22:3738-43. [PMID: 15315854 DOI: 10.1016/j.vaccine.2004.03.026] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2003] [Revised: 12/24/2003] [Accepted: 03/04/2004] [Indexed: 11/29/2022]
Abstract
Human Papillomavirus type 16 (HPV16) E6 and E7 oncoproteins are associated with cervical cancer development and progression and can therefore be used as target antigens for cancer immunotherapy. In this study we evaluated the immunogenicity in mice, of different vaccine formulations using recombinant HPV16 derived E6E7 or E7GST fusion proteins. When co-administered with ISCOMATRIX adjuvant, these E6E7 proteins consistently induced E7 specific CTL, in vivo tumor protection, antibody and DTH responses. ISCOMATRIX adjuvant has been developed for use in the formulation of novel human vaccines and has been evaluated for safety and toxicity in human trials. A formulation containing aluminum hydroxide (Al(OH)3) gave a lesser degree of E7 specific antibody, and no local E7 specific CTL response but similar DTH and tumor protection. These findings demonstrate the potential of ISCOMATRIX adjuvant to stimulate both cellular and humoral immune responses to endogenously processed target antigens, and hence is the preferred adjuvant when CTL responses are desirable.
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Affiliation(s)
- Trina J Stewart
- Centre for Immunology and Cancer Research, University of Queensland, Princess Alexandra Hospital, Brisbane, QLD 4102, Australia
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17
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Malliaros J, Quinn C, Arnold FH, Pearse MJ, Drane DP, Stewart TJ, Macfarlan RI. Association of antigens to ISCOMATRIX? adjuvant using metal chelation leads to improved CTL responses. Vaccine 2004; 22:3968-75. [PMID: 15364446 DOI: 10.1016/j.vaccine.2004.03.054] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2003] [Revised: 02/04/2004] [Accepted: 03/31/2004] [Indexed: 11/19/2022]
Abstract
The association of antigen with ISCOMATRIX trade mark adjuvant has been shown to be important for the optimal induction of cytotoxic T lymphocyte (CTL) responses. Here, we describe a simple broadly applicable method for associating recombinant proteins with hexa-histidine tags to ISCOMATRIX trade mark adjuvant utilising metal-affinity chelating interactions. The metal chelation binding step can be performed in a wide range of buffers, including commonly used denaturants such as urea, which makes it an ideal strategy for formulating proteins which are otherwise insoluble. Following association of protein with the chelating ISCOMATRIX trade mark adjuvant, the denaturant can be removed. Further, we show enhanced CTL responses with a protein-associated chelating ISCOMATRIX trade mark vaccine compared to a non-associated ISCOMATRIX trade mark vaccine.
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Affiliation(s)
- Jim Malliaros
- CSL Limited, R & D, Parkville, Vic. 3052, Australia.
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18
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Abstract
In Schistosoma mansoni and S. japonicum infection, the 22.6 kDa tegumental antigens Sm22.6 and Sj22.6 are principal targets for the human IgE response, and levels of IgE to Sm22.6 have been correlated with resistance to re-infection after chemotherapy. S. haematobium is arguably a more important species in terms of human infection, and in this report we describe for the first time the molecular characterization of a cDNA from S. haematobium (Sh22.6) that is closely homologous to Sm22.6 and Sj22.6. As a member of the tegument-associated antigen family, Sh22.6 possesses EF-hand domains and regions homologous to the dynein light chain domains. We have expressed recombinant Sh22.6 and studied the IgE responses to the antigen in a group of 99 infected individuals (68 children and 31 adults) from an endemic area of Gabon who donated blood before and 5 weeks after praziquantel treatment. IgE to Sh22.6 was detected by ELISA in 18 subjects (18%), and in the majority of responders levels rose between pre- and post-treatment. Interestingly, the proportion of adults expressing IgE to Sh22.6 was 35.5%, significantly higher than the 10.3% seen in children. IgE from at least 10 of the 18 ELISA responders recognized Sh22.6 on Western blots of adult worm extract and recombinant antigen. These results demonstrate that like related molecules in other species, Sh22.6 is a target for the human IgE response. The data also indicate that changes in the IgE response occur with age or with progressive exposure to key antigens.
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Affiliation(s)
- C M Fitzsimmons
- Department of Pathology, University of Cambridge, Cambridge, UK.
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19
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Stewart TJ, Smyth MJ, Fernando GJP, Frazer IH, Leggatt GR. Inhibition of early tumor growth requires J alpha 18-positive (natural killer T) cells. Cancer Res 2003; 63:3058-60. [PMID: 12810627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
The role of natural killer T (NKT) cells in the immune response to tumor cells has been largely unexplored. As a model of adoptive tumor immunotherapy, cells from the draining lymph nodes of mice immunized with a tumor-specific or irrelevant antigen were transferred to naïve recipients with established tumor. Inhibition of early tumor growth (day 4) required the transfer of both CD8(+) and J alpha 18(+) (NKT) cells from immunized animals without regard to immunogen. In contrast, CD8(+) cells, but not J alpha 18(+) cells, were necessary for the inhibition of late tumor growth (day 8). Thus, the developing tumor changes in sensitivity to NKT-mediated events and the role for NKT cells cannot be replaced by the presence of tumor-specific cells during early tumor growth. This suggests that recruitment/activation of J alpha 18(+) NKT cells is an important consideration during the immune therapy of early stage tumors.
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MESH Headings
- Animals
- Antigen Presentation
- Antigens, CD1/immunology
- Antigens, CD1d
- Antigens, Neoplasm/administration & dosage
- Antigens, Neoplasm/immunology
- CD8 Antigens/analysis
- CD8-Positive T-Lymphocytes/chemistry
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/transplantation
- Cell Transformation, Viral/immunology
- Cytotoxicity, Immunologic
- Disease Progression
- Female
- Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor
- Glycolipids/immunology
- Immunization
- Immunotherapy, Adoptive
- Killer Cells, Natural/chemistry
- Killer Cells, Natural/classification
- Killer Cells, Natural/immunology
- Killer Cells, Natural/transplantation
- Mice
- Mice, Inbred C57BL
- Mice, SCID
- Neoplasm Transplantation
- Neoplasms, Experimental/immunology
- Neoplasms, Experimental/therapy
- Oncogene Proteins, Viral/administration & dosage
- Oncogene Proteins, Viral/immunology
- Papillomavirus E7 Proteins
- Receptors, Antigen, T-Cell, alpha-beta/analysis
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- T-Lymphocyte Subsets/chemistry
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/transplantation
- Time Factors
- Tumor Escape/immunology
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Affiliation(s)
- Trina J Stewart
- Centre for Immunology and Cancer Research, University of Queensland, Princess Alexandra Hospital, Brisbane, Queensland, 4102, Australia
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20
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Liu S, Qu Y, Stewart TJ, Howard MJ, Chakrabortty S, Holekamp TF, McDonald JW. Embryonic stem cells differentiate into oligodendrocytes and myelinate in culture and after spinal cord transplantation. Proc Natl Acad Sci U S A 2000; 97:6126-31. [PMID: 10823956 PMCID: PMC18569 DOI: 10.1073/pnas.97.11.6126] [Citation(s) in RCA: 448] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Demyelination contributes to the loss of function consequent to central nervous system (CNS) injury. Enhanced remyelination through transplantation of myelin-producing cells may offer a pragmatic approach to restoring meaningful neurological function. An unlimited source of cells suitable for such transplantation therapy can be derived from embryonic stem (ES) cells, which are both pluripotent and genetically flexible. In this paper we show that oligodendrocyte cultures can be reliably produced from retinoic acid-induced ES cells and that these oligodendrocytes can myelinate axons in vitro. Methods were further developed for generating highly enriched cultures of oligodendrocytes through an additional culturing step, producing an intermediate "oligosphere" stage. To test whether ES cells can survive, migrate, and differentiate into mature myelin-producing cells in areas of demyelination in the adult CNS, ES cells were transplanted into the dorsal columns of adult rat spinal cord 3 days after chemical demyelination. In the demyelination site, large numbers of ES cells survived and differentiated primarily into mature oligodendrocytes that were capable of myelinating axons. Furthermore, when oligosphere cells were transplanted into the spinal cords of myelin-deficient shiverer (shi/shi) mutant mice, the ES cell-derived oligodendrocytes migrated into the host tissue, produced myelin and myelinated host axons. These studies demonstrate the ability of ES cell-derived oligodendrocytes to myelinate axons in culture and to replace lost myelin in the injured adult CNS. Transplantation of ES cells may be a practical approach to treatment of primary and secondary demyelinating diseases in the adult CNS.
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Affiliation(s)
- S Liu
- Center for the Study of Nervous System Injury, and Department of Neurology, Washington University School of Medicine, Box 8111, St. Louis, MO 63110, USA
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21
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Fernando GJP, Stewart TJ, Tindle RW, Frazer IH. Th2-Type CD4+ Cells Neither Enhance nor Suppress Antitumor CTL Activity in a Mouse Tumor Model. The Journal of Immunology 1998. [DOI: 10.4049/jimmunol.161.5.2421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Many cervical cancers express the E7 protein of human papillomavirus 16 as a tumor-specific Ag (TSA). To establish the role of E7-specific T cell help in CD8+ CTL-mediated tumor regression, C57BL/6J mice were immunized with E7 protein or with a peptide (GF001) comprising a minimal CTL epitope of E7, together with different adjuvants. Immunized mice were challenged with an E7-expressing tumor cell line, EL4.E7. Growth of EL4.E7 was reduced following immunization with E7 and Quil-A (an adjuvant that induced a Th1-type response to E7) or with GF001 and Quil-A. Depletion of CD8+ cells, but not CD4+ cells, from an immunized animal abrogated protection, confirming that E7-specific CTL are necessary and sufficient for TSA-specific protection in this model. Immunization with E7 and Algammulin (an alum-based adjuvant) induced a Th2-like response and provided no tumor protection. To investigate whether a Th2 T helper response to E7 could prevent the development of an E7-specific CTL-mediated protection, mice were simultaneously immunized with E7/Algammulin and GF001/Quil-A or, alternatively, were immunized with GF001/Quil-A 8 wk after immunization with E7/Algammulin. Tumor protection was observed in each case. We conclude that an established Th2 response to a TSA does not prevent the development of TSA-specific tumor protective CTL.
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Affiliation(s)
- Germain J. P. Fernando
- Center for Immunology and Cancer Research, University of Queensland Department of Medicine, Princess Alexandra Hospital, Brisbane, Queensland, Australia
| | - Trina J. Stewart
- Center for Immunology and Cancer Research, University of Queensland Department of Medicine, Princess Alexandra Hospital, Brisbane, Queensland, Australia
| | - Robert W. Tindle
- Center for Immunology and Cancer Research, University of Queensland Department of Medicine, Princess Alexandra Hospital, Brisbane, Queensland, Australia
| | - Ian H. Frazer
- Center for Immunology and Cancer Research, University of Queensland Department of Medicine, Princess Alexandra Hospital, Brisbane, Queensland, Australia
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22
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Fernando GJ, Stewart TJ, Tindle RW, Frazer IH. Th2-type CD4+ cells neither enhance nor suppress antitumor CTL activity in a mouse tumor model. J Immunol 1998; 161:2421-7. [PMID: 9725239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Many cervical cancers express the E7 protein of human papillomavirus 16 as a tumor-specific Ag (TSA). To establish the role of E7-specific T cell help in CD8+ CTL-mediated tumor regression, C57BL/6J mice were immunized with E7 protein or with a peptide (GF001) comprising a minimal CTL epitope of E7, together with different adjuvants. Immunized mice were challenged with an E7-expressing tumor cell line, EL4.E7. Growth of EL4.E7 was reduced following immunization with E7 and Quil-A (an adjuvant that induced a Th1-type response to E7) or with GF001 and Quil-A. Depletion of CD8+ cells, but not CD4+ cells, from an immunized animal abrogated protection, confirming that E7-specific CTL are necessary and sufficient for TSA-specific protection in this model. Immunization with E7 and Algammulin (an alum-based adjuvant) induced a Th2-like response and provided no tumor protection. To investigate whether a Th2 T helper response to E7 could prevent the development of an E7-specific CTL-mediated protection, mice were simultaneously immunized with E7/Algammulin and GF001/Quil-A or, alternatively, were immunized with GF001/Quil-A 8 wk after immunization with E7/Algammulin. Tumor protection was observed in each case. We conclude that an established Th2 response to a TSA does not prevent the development of TSA-specific tumor protective CTL.
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MESH Headings
- Adjuvants, Immunologic/pharmacology
- Alum Compounds
- Amino Acid Sequence
- Animals
- Antigens, Neoplasm/biosynthesis
- Antigens, Neoplasm/genetics
- Antigens, Neoplasm/immunology
- CD8-Positive T-Lymphocytes/immunology
- Cytotoxicity, Immunologic/immunology
- Disease Models, Animal
- Drug Combinations
- Epitopes, T-Lymphocyte/genetics
- Epitopes, T-Lymphocyte/immunology
- Female
- Immunity, Active
- Inulin/immunology
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Nude
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Oncogene Proteins, Viral/biosynthesis
- Oncogene Proteins, Viral/genetics
- Oncogene Proteins, Viral/immunology
- Papillomaviridae/immunology
- Papillomavirus E7 Proteins
- Peptide Fragments/immunology
- Quillaja Saponins
- Saponins/immunology
- Skin Neoplasms/genetics
- Skin Neoplasms/immunology
- Skin Neoplasms/prevention & control
- T-Lymphocytes, Cytotoxic/immunology
- Th2 Cells/immunology
- Thymoma/genetics
- Thymoma/immunology
- Thymoma/prevention & control
- Tumor Cells, Cultured
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Affiliation(s)
- G J Fernando
- Center for Immunology and Cancer Research, University of Queensland Department of Medicine, Princess Alexandra Hospital, Brisbane, Australia
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23
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Fernando GJ, Stewart TJ, Tindle RW, Frazer IH. Vaccine-induced Th1-type responses are dominant over Th2-type responses in the short term whereas pre-existing Th2 responses are dominant in the longer term. Scand J Immunol 1998; 47:459-65. [PMID: 9627130 DOI: 10.1046/j.1365-3083.1998.00327.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The effect of adjuvant on induction of human papillomavirus type 16 E7 protein-specific cytotoxic T lymphocytes (CTL) and immunoglobulin G (IgG)2a antibody was studied in C57BL/6 J mice immunized with various adjuvants and E7 protein. Quil-A adjuvant, but not complete Freund's adjuvant (CFA) or Algammulin, induced a T-helper 1 (Th1)-type response to E7, which was characterized by CTL activity against a tumour cell line transfected with E7 protein and by E7-specific IgG2a. All tested adjuvants elicited comparable levels of E7-specific IgG1. The longest duration and greatest magnitude of CTL response was seen following two immunizations with the highest dose of E7 and Quil-A. Simultaneous immunization with a Th1 and a T helper 2 (Th2)-promoting adjuvant gave a Th1-type response. However, E7 and Quil-A were unable to induce a Th1-type response (as measured by the inability to generate anti-E7 IgG2a antibody) in animals with a pre-existing Th2-type response to E7. These results suggest that saponin adjuvants may be suitable for immunotherapy in humans where a Th1-type response is sought, provided that there is no pre-existing Th2-type response to the antigen.
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Affiliation(s)
- G J Fernando
- Centre for Immunology & Cancer Research, University of Queensland, Department of Medicine, Princess Alexandra Hospital, Brisbane, Australia
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24
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Abstract
A case is reported of oat cell carcinoma of the lung presenting with unusual sites of metastasis to the orofacial region. Distant metastases are common in oat cell carcinoma but a literature review did not reveal any reports of metastases either to the hard palate or to medial canthus of the eye.
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Affiliation(s)
- R Capper
- Department of Otolaryngology, Ulster Hospital, Belfast
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25
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Abstract
The complete sequence of the cDNA encoding a 20 kDa calcium-binding protein of Schistosoma mansoni (Sm20) has been determined. The predicted amino acid sequence contains 4 EF hand domains but examination of the predicted secondary structure of Sm20, together with the specific residues in each calcium-binding domain, suggests that only 1 EF hand (domain IV) is functional. Sm20 is most homologous to calmodulin, troponin C and the regulatory light-chain of myosin, particularly those of invertebrates. However, troponin C and the regulatory light-chain of myosin can be distinguished from Sm20 by size and by their differential levels of expression during the life-cycle. Sm20 also appears to be distinct from calmodulin but may be functionally equivalent to the soluble sarcoplasmic calcium-binding proteins of molluscs and crustacea which may act as a reservoir for calcium in muscle. Sm20 is encoded by a small multi-gene family whose members are clustered within a 15 kb region of the genome. A 20 kDa antigen, cross-reactive with Sm20, is expressed in Schistosoma haematobium, Fasciola hepatica and Paragonomus mexicanus.
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Affiliation(s)
- T J Stewart
- Department of Pathology, University of Cambridge
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26
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Abstract
Pneumocystis pneumonia is rarely identified in the many immunosuppressed individuals with acquired immune deficiency syndrome (AIDS) and malnutrition in Africa. To test whether infection with Pneumocystis carinii occurs in the continent we conducted a comparative serological study, measuring by enzyme-linked immunosorbent assay antibodies to the parasite in 150 healthy young individuals from both Britain and the Gambian savanna. The prevalence of significant titres of antibody to P. carinii steadily increased with age and included more than 70% of both populations by 8 years of age. Infection with P. carinii is, therefore, common in the Gambia. Thus opportunistic pneumocystis pneumonia may be an important but largely unrecognized disease in the continent, though its impact is probably diminished by the prevalence of fatal tuberculous infection, particularly in the AIDS population.
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Affiliation(s)
- A E Wakefield
- Institute of Molecular Medicine and Osler Chest Unit, Oxford, UK
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27
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Abstract
Idiopathic glossopharyngeal neuralgia is an uncommon disorder which often fails to respond to medical treatment. Surgical treatment most commonly consists of intracranial section of the glossopharyngeal nerve and upper vagal rootlets. We present three cases treated by the much simpler pharyngeal approach and argue that in appropriately selected patients this approach should receive more serious consideration.
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Affiliation(s)
- A P Mairs
- Ulster Hospital, Dundonald, Belfast, Northern Ireland
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28
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Abstract
Decreased fetal heart rate variability was noted 90 seconds after the induction of general anesthesia with sodium thiopentone and fentanyl in a patient undergoing basket extraction of a renal calculus at 30 weeks' gestation. The fetal sleep pattern lasted for 105 minutes after the anesthetic was discontinued, 45 minutes after the mother was fully awake.
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Affiliation(s)
- D M Fedorkow
- Department of Obstetrics and Gynecology, Foothills Provincial General Hospital, Calgary, Alberta, Canada
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29
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Affiliation(s)
- A E Wakefield
- University Department of Paediatrics, John Radcliffe Hospital, Oxford, England
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30
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Wakefield AE, Hopkin JM, Burns J, Hipkiss JB, Stewart TJ, Moxon ER. Cloning of DNA from Pneumocystis carinii. J Infect Dis 1988; 158:859-62. [PMID: 3262696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Affiliation(s)
- A E Wakefield
- Department of Pediatrics and Pathology, University of Oxford, John Radcliffe Hospital, England
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31
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McIlwain JC, Toner JG, Stewart TJ, Kwok O, Campbell JB, Hunter J. The flora of the tonsil and post-operative fossa in adult tonsillectomy patients. J Laryngol Otol 1988; 102:598-600. [PMID: 3411210 DOI: 10.1017/s0022215100105821] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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32
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Abstract
The tonsil flora of 20 children below the age of 4 years undergoing tonsillectomy, and a control group of 18 children were studied using tonsil swabs and core specimens. The study group had a significantly higher culture rate of anaerobic organisms, whereas there was no significant difference between the groups in respect of aerobic pathogens. Since most anaerobic organisms are relatively resistant to the antibiotics usually prescribed for recurring tonsillitis, the use of more appropriate antimicrobial therapy may be helpful in the prevention of early tonsillectomy.
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33
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Pantell RH, Stewart TJ, Dias JK, Wells P, Ross AW. Physician communication with children and parents. Pediatrics 1982; 70:396-402. [PMID: 7110814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The way physicians communicate with patients has been shown to affect physiologic measurements, adherence to therapeutic regimens, and satisfaction with medical care. The purpose of this study was to document the content of medical interviews in routine pediatric visits and to identify demographic and situational characteristics that influenced the extent of communication between doctor and child. One hundred fifteen office visits to 49 physicians were videotaped and analyzed. Children studied were 4 to 14 years old with a mean age of 8.5 years. Verbal transactions were coded according to direction of communication, transaction type, and content category. Coder reliability for this system was 0.84. A considerable amount of the total communication, 45.5%, was between doctor and child. Doctors interacted differently with parents and children. More information about the current problem was obtained from children; physicians provided feedback primarily to parents. Parents received 4.4. times as much information as children about the nature and prognosis of a condition. The extent to which doctors talked to children in "substantive" areas was primarily associated with a child's age (r = .52, P less than .001) but was partly influenced by family size (r = .20, P less than .05) and family utilization (r = .22, P less than .02). Race, socioeconomic status, type of problem, and previous encounter with the examining physician did not alter communication patterns. Boys were given more information than girls (6.5% vs 4.0%, P less than .01). We suggest a theoretical framework for future investigation and teaching that identifies the child as an active participant in the medical process.
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34
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Abstract
Effects of garlic on lipid metabolism were studied in three experiments using different aged male rats fed a diet containing 1% cholesterol or 15% lard. Lyophilized garlic was supplemented at 2% and 4% of the diet. Plasma glucose was not changed by dietary treatments. Rats fed cholesterol and lard diets increased plasma cholesterol and triglycerides compared to controls. Garlic decreased plasma cholesterol in cholesterol- and lard-fed rats, but decreased plasma triglycerides only in the lard-fed group. Garlic supplementation decreased very low density lipoprotein cholesterol and increased high density lipoprotein cholesterol. The liver weight, total liver lipid and cholesterol were increased in rats fed the cholesterol diet but a supplementation of garlic decreased those parameters by about 30%. Dietary cholesterol and lard decreased hepatic glucose-6-phosphate dehydrogenase and malic enzyme activities: the garlic supplementation further decreased these enzyme activities. Garlic feeding increased the excretion of the neutral steroids in both 16-week and 10-week-old rats and bile acids in only 16-week-old pair-fed rats. Garlic at the 2% level was similarly effective on lipid metabolism as at 4%. These results demonstrate that garlic increases the excretion of neutral and acidic steroids and exerts hypocholesterolemic effects in cholesterol-fed rats.
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35
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Brod RL, May PA, Stewart TJ. Recruitment and retention of federal physicians on the Navajo Reservation. Soc Sci J 1982; 19:47-66. [PMID: 11615157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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36
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Stewart TJ, Pantell RH, Dias JK, Wells PA, Ross AW. Children as patients: a communications process study in family practice. J Fam Pract 1981; 13:827-835. [PMID: 7031173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
To determine how family physicians divide their attention between children and parents, 115 videotaped pediatric encounters of children (aged 4 to 14 years) and parents with family physicians in a family medicine center were analyzed. It was learned that physicians tended to involve children actively in the diagnostic stages of interviews but much less so in discussions of treating or dealing with their problems. Physicians did not alter this pattern as they advanced in training. Older children were more likely to receive direct communication from physicians in all phases of office encounters. Though the family physicians in this sample had more direct communication with children than reported in previous research, it is argued that greater involvement of children in all phases of pediatric visits is warranted. A developmental framework indicates that children gradually evolve their attitudes, concepts, and behaviors around illness and health. Family physicians and family medicine programs are in an excellent position to explore and utilize the practice of actively incorporating a child in a medical interview.
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37
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Abstract
A study of the surgical anatomy and pathology of the round window was performed on a total of 292 serially sectioned temporal bones. The surgical approach to the round window is discussed with consideration of the anatomical findings. In the pathological study obliteration of the round window niche occurred as a congenital anomaly, in otosclerosis, chronic otitis media and as an end result in suppurative labyrinthitis. Clinical reports seem to indicate that obliteration of the window is associated with significant hearing loss, contrary to the findings in experimental animals. In chronic otitis media the round window is a pathway for spread of infection to the labyrinth, but also the finding of perilymphatic precipitates to the window in some ears suggests that certain inflammatory products may enter the scala tympani through the round window and so lead to high tone sensorineural hearing loss.
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38
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39
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Pantell RH, Stewart TJ. The pneumococcal vaccine. Immunization at a crossroad. JAMA 1979; 241:2272-4. [PMID: 439296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A new polyvalent pneumococcal vaccine (Pneumovax) was released in February 1978. In an effort to chronicle the dissemination of the vaccine to high-risk patients, we prospectively followed up a single clinic population and conducted a telephone survey of three neighborhood health centers, two private practices, and a university hematology clinic. Three months after notification of the vaccine arrival, physicians in the prospectively chronicled clinic had immunized six of 12 patients with sickle cell disease, five of 80 patients with chronic obstructive pulmonary disease, three of 225 patients with diabetes, and three of 45 patients older than 80 years. Immunization policy in the other clinics surveyed varied greatly. As an attempt to curb low-prevalence, high-severity illness in a small target population, the pneumococcal vaccine presents a new set of problems in the systematic implementation of an immunization.
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40
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Abstract
Five small occult schwannomas of the vestibular nerve were discovered on routine examination of 893 serially sectioned temporal bones of 517 individuals. Three arose from the superior division, one from the inferior division, and the other had a multicentric origin from both divisions of the nerve. Location and size of these tumors indicate that clinical diagnosis would have been difficult or impossible by any method of study. The finding of vestibular schwannomas in 0.9% of individuals in this series, indicates the high incidence of this tumor in the general population. The much lower incidence of diagnosed symptomatic tumors in the general population can only be explained by the conclusion that this neoplasm exhibits considerable variation in growth characteristics. Usually the tumor enlarges so slowly as to be of no health importance, but occasionally it grows more rapidly to become symptomatic and require surgical removal.
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41
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Antoli-Candela F, Stewart TJ. The pathophysiology of otologic facial paralysis. Otolaryngol Clin North Am 1974; 7:309-30. [PMID: 4599259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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42
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Abstract
A histological study was made of the middle ear joints in association with several middle ear disorders, including congenital anomalies, acute and chronic otitis media, congenital syphilis, otosclerosis, Paget's disease, and primary and secondary neoplasms. Although the numbers of cases are small, the data suggest that the degenerative changes in the joints are more severe and in higher incidence than expected as a function of aging. Whereas advanced changes may be present, including fusion of the articular surfaces, it seems improbable that the joint changes contribute to the conductive hearing losses existing in these ears.
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Stewart TJ, Bell M. The treatment of pilonidal sinus by phenol injection. Ulster Med J 1969; 38:167-71. [PMID: 5345246 PMCID: PMC2385015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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