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Agas D, Gusmão Silva G, Laus F, Marchegiani A, Capitani M, Vullo C, Catone G, Lacava G, Concetti A, Marchetti L, Sabbieti MG. INF-γ encoding plasmid administration triggers bone loss and disrupts bone marrow microenvironment. J Endocrinol 2017; 232:309-321. [PMID: 27908965 DOI: 10.1530/joe-16-0538] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Accepted: 11/29/2016] [Indexed: 12/12/2022]
Abstract
IFN-γ is a pleotropic cytokine produced in the bone microenvironment. Although IFN-γ is known to play a critical role on bone remodeling, its function is not fully elucidated. Consistently, outcomes on the effects of IFN-γ recombinant protein on bone loss are contradictory among reports. In our work we explored, for the first time, the role of IFN-γ encoding plasmid (pIFN-γ) in a mouse model of osteopenia induced by ovariectomy and in the sham-operated counterpart to estimate its effects in skeletal homeostasis. Ovariectomy produced a dramatic decrease of bone mineral density (BMD). pINF-γ injected mice showed a pathologic bone and bone marrow phenotype; the disrupted cortical and trabecular bone microarchitecture was accompanied by an increased release of pro-inflammatory cytokine by bone marrow cells. Moreover, mesenchymal stem cells' (MSCs) commitment to osteoblast was found impaired, as evidenced by the decline of osterix-positive (Osx+) cells within the mid-diaphyseal area of femurs. For instance, a reduction and redistribution of CXCL12 cells have been found, in accordance with bone marrow morphological alterations. As similar effects were observed both in sham-operated and in ovariectomized mice, our studies proved that an increased IFN-γ synthesis in bone marrow might be sufficient to induce inflammatory and catabolic responses even in the absence of pathologic predisposing substrates. In addition, the obtained data might raise questions about pIFN-γ's safety when it is used as vaccine adjuvant.
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Affiliation(s)
- Dimitrios Agas
- School of Bioscience and Veterinary MedicineUniversity of Camerino, Camerino, Italy
| | - Guilherme Gusmão Silva
- Departamento de Bioquímica e ImunologiaUniversidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Fulvio Laus
- School of Bioscience and Veterinary MedicineUniversity of Camerino, Camerino, Italy
| | - Andrea Marchegiani
- School of Bioscience and Veterinary MedicineUniversity of Camerino, Camerino, Italy
| | - Melania Capitani
- School of Bioscience and Veterinary MedicineUniversity of Camerino, Camerino, Italy
| | - Cecilia Vullo
- School of Bioscience and Veterinary MedicineUniversity of Camerino, Camerino, Italy
| | - Giuseppe Catone
- School of Bioscience and Veterinary MedicineUniversity of Camerino, Camerino, Italy
| | - Giovanna Lacava
- School of Bioscience and Veterinary MedicineUniversity of Camerino, Camerino, Italy
| | - Antonio Concetti
- School of Bioscience and Veterinary MedicineUniversity of Camerino, Camerino, Italy
| | - Luigi Marchetti
- School of Bioscience and Veterinary MedicineUniversity of Camerino, Camerino, Italy
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Lee MSJ, Igari Y, Tsukui T, Ishii KJ, Coban C. Current status of synthetic hemozoin adjuvant: A preliminary safety evaluation. Vaccine 2016; 34:2055-61. [DOI: 10.1016/j.vaccine.2016.02.064] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 02/09/2016] [Accepted: 02/24/2016] [Indexed: 12/21/2022]
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Ma Y, An HJ, Wei XQ, Xu Q, Yu YZ, Sun ZW. Enhanced potency of replicon vaccine using one vector to simultaneously co-express antigen and interleukin-4 molecular adjuvant. Hum Vaccin Immunother 2013; 9:242-9. [PMID: 23291932 DOI: 10.4161/hv.22888] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
We evaluated the utility of interleukin-4 (IL-4) as molecular adjuvant of replicon vaccines for botulinum neurotoxin serotype A (BoNT/A) in mouse model. In both Balb/c and C57/BL6 mice that received the plasmid DNA replicon vaccines derived from Semliki Forest virus (SFV) encoding the Hc gene of BoNT/A (AHc), the immunogenicity was significantly modulated and enhanced by co-delivery or co-express of the IL-4 molecular adjuvant. The enhanced potencies were also produced by co-delivery or co-expression of the IL-4 molecular adjuvant in mice immunized with the recombinant SFV replicon particles (VRP) vaccines. In particular, when AHc and IL-4 were co-expressed within the same replicon vaccine vector using dual-expression or bicistronic IRES, the anti-AHc antibody titers, serum neutralization titers and survival rates of immunized mice after challenged with BoNT/A were significantly increased. These results indicate IL-4 is an effective Th2-type adjuvant for the replicon vaccines in both strain mice, and the co-expression replicon vaccines described here may be an excellent candidate for further vaccine development in other animals or humans. Thus, we described a strategy to design and develop efficient vaccines against BoNT/A or other pathogens using one replicon vector to simultaneously co-express antigen and molecular adjuvant.
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Affiliation(s)
- Yao Ma
- College of Life Science and Bioengineering; Beijing Jiaotong University; Beijing, PR China
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Gene gun bombardment with DNA-coated golden particles enhanced the protective effect of a DNA vaccine based on thioredoxin glutathione reductase of Schistosoma japonicum. BIOMED RESEARCH INTERNATIONAL 2012; 2013:952416. [PMID: 23509820 PMCID: PMC3591203 DOI: 10.1155/2013/952416] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 08/19/2012] [Accepted: 09/09/2012] [Indexed: 12/24/2022]
Abstract
Schistosomiasis, caused by infection with Schistosoma species, remains an important parasitic zoonosis. Thioredoxin glutathione reductase of Schistosoma japonicum (SjTGR) plays an important role in the development of the parasite and for its survival. Here we present a recombinant plasmid DNA vaccine, pVAX1/SjTGR, to estimate its protection against S. japonicum in BALB/c mice. The DNA vaccine administrated by particle bombardment induced higher protection than by intramuscular injection. All animals vaccinated with pVAX1/SjTGR developed significant specific anti-SjTGR antibodies than control groups. Moreover, animals immunized by gene gun exhibited a splenocyte proliferative response, with an increase in IFN-γ and IL-4. The recombinant plasmid administrated by gene gun achieved a medium protective efficacy of 27.83–38.83% (P < 0.01) of worm reduction and 40.38–44.51% (P < 0.01) of liver egg count reduction. It suggests that different modes of administering a DNA vaccine can influence the protective efficacy induced by the vaccine. Interestingly, from the enzymatic activity results, we found that worms obtained from pVAX1/SjTGR-vaccinated animals expressed lower enzymatic activity than the control group and the antibodies weakened the enzymatic activity of SjTGR in vitro, too. It implies that the high-level antibodies may contribute to the protective effects.
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Kong X, Zhang W, Lockey RF, Auais A, Piedimonte G, Mohapatra SS. Respiratory syncytial virus infection in Fischer 344 rats is attenuated by short interfering RNA against the RSV-NS1 gene. GENETIC VACCINES AND THERAPY 2007; 5:4. [PMID: 17270047 PMCID: PMC1805440 DOI: 10.1186/1479-0556-5-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Accepted: 02/01/2007] [Indexed: 11/21/2022]
Abstract
Background Respiratory syncytial virus (RSV) causes severe bronchiolitis and is a risk factor for asthma. Since there is no commercially available vaccine against RSV, a short interfering RNA against the RSV-NS1gene (siNS1) was developed and its potential for decreasing RSV infection and infection-associated inflammation in rats was tested. Methods Plasmids encoding siNS1 or an unrelated siRNA were complexed with a chitosan nanoparticle delivery agent and administered intranasally. Control animals received a plasmid for a non-specific siRNA. After expression of the plasmid in lung cells for 24 hours, the rats were intranasally infected with RSV. Results Prophylaxis with siNS1 significantly reduced lung RSV titers and airway hyperreactivity to methacholine challenge compared to the control group. Lung sections from siNS1-treated rats showed a sizable reduction in goblet cell hyperplasia and in lung infiltration by inflammatory cells, both characteristics of asthma. Also, bronchoalveolar lavage samples from siNS1-treated animals had fewer eosinophils. Treatment of rats with siNS1 prior to RSV exposure was effective in reducing virus titers in the lung and in preventing the inflammation and airway hyperresponsiveness associated with the infection that has been linked to development of asthma. Conclusion The use of siNS1 prophylaxis may be an effective method for preventing RSV bronchiolitis and potentially reducing the later development of asthma associated with severe respiratory infections.
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Affiliation(s)
- Xiaoyuan Kong
- University of South Florida College of Medicine, Florida, USA
| | - Weidong Zhang
- University of South Florida College of Medicine, Florida, USA
| | | | - Alexander Auais
- Batchelor Children's Institute, University of Miami, Miami, Florida, USA
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Pedras-Vasconcelos JA, Goucher D, Puig M, Tonelli LH, Wang V, Ito S, Verthelyi D. CpG oligodeoxynucleotides protect newborn mice from a lethal challenge with the neurotropic Tacaribe arenavirus. THE JOURNAL OF IMMUNOLOGY 2006; 176:4940-9. [PMID: 16585590 DOI: 10.4049/jimmunol.176.8.4940] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The innate immune system is key to limiting the early spread of most pathogens and directing the development of Ag-specific immunity. Recently, a number of synthetic molecules that activate the innate immune system by stimulating TLRs have been identified. Among them, synthetic oligodeoxynucleotides (ODNs) containing unmethylated CpG motifs (CpG ODNs) were shown to activate TLR9-bearing B cells, macrophages, and dendritic cells to induce a strong proinflammatory milieu and a type 1-biased immune response that protects mice from a variety of parasitic, bacterial, and viral infections. Although the protective effect of CpG ODN in adult mice was well established, its effectiveness in neonates, which have lower numbers of dendritic, B, and T cells and tend to favor Th2 responses, was unclear. This study uses the New World arenavirus Tacaribe, a neurotropic pathogen that is lethal in newborn mice, to explore the effectiveness of TLR-mediated innate immune responses. Neonatal BALB/c mice treated with CpG ODN at the time of infection had reduced viral load (p < 0.01) and increased survival (52%, p < 0.001 i.p.; 36%, p < 0.05 intranasally). Protection was achieved in mice treated no later than 3 days postchallenge and appears to be mediated by an increase in Ag-specific Abs (IgG and IgM) and to require inducible NO synthase expression and NO production. To our knowledge, this is the first study assessing the mechanisms by which CpG ODN can protect mice from a neurotropic viral infection.
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Affiliation(s)
- João A Pedras-Vasconcelos
- Division of Therapeutic Proteins, Office of Biotechnology Products, Center for Drug Evaluation and Research, Federal Drug Administration, Bethesda, MD 20892, USA
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Ishii KJ, Ito S, Tamura T, Hemmi H, Conover J, Ozato K, Akira S, Klinman DM. CpG-activated Thy1.2+ dendritic cells protect against lethalListeria monocytogenes infection. Eur J Immunol 2005; 35:2397-405. [PMID: 16047338 DOI: 10.1002/eji.200425795] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Synthetic oligodeoxynucleotides containing CpG motifs (CpG ODN) activate the innate immune system by interacting with Toll-like receptor 9. The resultant immune response increases host resistance to infection by a variety of pathogenic microorganisms, including Listeria monocytogenes. There is a considerable interest in harnessing the immunoprotective properties of CpG ODN, yet little is known of the cell phenotype(s) responsible for mediating this protection. This work demonstrates that treatment of mice with CpG ODN increases the number of Thy1.2+, CD11c+ dendritic cells (Thy1.2+ DC) in the spleen, which are both necessary and sufficient for transferring resistance to infection from CpG-treated donors to naive recipients. These CpG-activated Thy1.2+ DC are distinct from conventional (CD11c(hi), Thy1.2-) or plasmacytoid DC (mPDCA+), and secrete IFN-gamma that contributes to protection. These findings suggest that a novel Thy1.2+ DC subset plays a critical role in mediating the immunoprotective activity of CpG DNA.
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Affiliation(s)
- Ken J Ishii
- Section of Retroviral Immunology, Center for Biologics Evaluation Research, Food and Drug Administration, Bethesda, MD 20892, USA
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Chakrabarti R, Chang Y, Song K, Prud'homme GJ. Plasmids encoding membrane-bound IL-4 or IL-12 strongly costimulate DNA vaccination against carcinoembryonic antigen (CEA). Vaccine 2004; 22:1199-205. [PMID: 15003648 DOI: 10.1016/j.vaccine.2003.09.023] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2003] [Revised: 09/24/2003] [Accepted: 09/24/2003] [Indexed: 11/27/2022]
Abstract
Vaccination with plasmids encoding an antigen of interest (DNA vaccination) is a new strategy to achieve effective immunization against many agents. DNA vaccination can be ameliorated by co-administration of plasmids encoding a cytokine. Thus far, only plasmids encoding soluble cytokines have been used for this purpose. However, these plasmids can induce release of cytokines into the circulation and could potentially cause many undesirable effects. We undertook this study to determine whether membrane-bound cytokines, which would restrict their localization at the site of administration, can act as immunoadjuvants. We and others have previously shown that plasmids encoding soluble IL-4 and IL-12 are effective adjuvants for DNA vaccination. In this study, we demonstrate that DNA co-vaccination with membrane-bound IL-4 (mbIL-4) or membrane-bound IL-12 (mbIL-12) both enhance anti-CEA immunity, as detected by in vitro and in vivo assays. Mice co-injected with plasmids encoding CEA and either type of membrane-bound cytokine rejected transplanted CEA-positive tumor cells strongly. Notably, unlike secreted IL-4, mbIL-4 was the most effective adjuvant for anti-tumor immunity. This study demonstrates that membrane-bound cytokines are suitable adjuvants for DNA vaccination.
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Affiliation(s)
- Rabindranath Chakrabarti
- Department of Laboratory Medicine and Pathobiology, St. Micheal's Hospital and University of Toronto, 30 Bond Street, Toronto, Ont., Canada M5B 1W8
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Ghochikyan A, Vasilevko V, Petrushina I, Movsesyan N, Babikyan D, Tian W, Sadzikava N, Ross T, Head E, Cribbs DH, Agadjanyan MG. Generation and characterization of the humoral immune response to DNA immunization with a chimeric beta-amyloid-interleukin-4 minigene. Eur J Immunol 2003; 33:3232-41. [PMID: 14635031 PMCID: PMC1524857 DOI: 10.1002/eji.200324000] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Active immunization with fibrillar beta-amyloid peptide (Abeta(42)) as well as passive transfer of anti-Abeta antibodies significantly reduces Abeta plaque deposition, neuritic dystrophy, and astrogliosis in the brain of mutant amyloid precursor protein (APP)-transgenic mice. Although the mechanism(s) of clearance of Abeta from the brain following active or passive immunization remains to be determined, it is clear that anti-Abeta antibodies are critical for clearance. DNA immunization provides an attractive alternative to direct peptide and adjuvant approaches for inducing a humoral response to Abeta. We constructed a DNA minigene with Abeta fused to mouse interleukin-4 (pAbeta(42)-IL-4) as a molecular adjuvant to generate anti-Abeta antibodies and enhance the Th2-type of immune responses. Gene gun immunizations induced primarily IgG1 and IgG2b anti-Abeta antibodies. Fine epitope analysis with overlapping peptides of the Abeta(42) sequence identified the 1-15 region as a dominant B cell epitope. The DNA minigene-induced anti-Abeta antibodies bound to Abeta plaques in brain tissue from an Alzheimer's disease patient demonstrating functional activity of the antibodies and the potential for therapeutic efficacy.
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Affiliation(s)
- Anahit Ghochikyan
- The Institute for Molecular Medicine, Department of Immunology, Huntington Beach, USA
| | - Vitaly Vasilevko
- The Institute for Molecular Medicine, Department of Immunology, Huntington Beach, USA
| | - Irina Petrushina
- The Institute for Brain Aging and Dementia, University of California, Irvine, USA
| | - Nina Movsesyan
- The Institute for Molecular Medicine, Department of Immunology, Huntington Beach, USA
| | - Davit Babikyan
- The Institute for Molecular Medicine, Department of Immunology, Huntington Beach, USA
| | - Wenqiang Tian
- Department of Molecular Biology and Biochemistry, University of California, Irvine, USA
| | - Nadya Sadzikava
- The Institute for Brain Aging and Dementia, University of California, Irvine, USA
| | - TedM. Ross
- Department of Microbiology and Immunology, East Carolina University School of Medicine, Greenville, USA
| | - Elizabeth Head
- The Institute for Brain Aging and Dementia, University of California, Irvine, USA
| | - David H. Cribbs
- The Institute for Brain Aging and Dementia, University of California, Irvine, USA
| | - Michael G. Agadjanyan
- The Institute for Molecular Medicine, Department of Immunology, Huntington Beach, USA
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Furusawa E, Hirazumi A, Story S, Jensen J. Antitumour potential of a polysaccharide-rich substance from the fruit juice ofMorinda citrifolia (Noni) on sarcoma 180 ascites tumour in mice. Phytother Res 2003; 17:1158-64. [PMID: 14669249 DOI: 10.1002/ptr.1307] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
An immunomodulatory polysaccharide-rich substance (Noni-ppt) from the fruit juice of Morinda citrifolia has been found to possess both prophylactic and therapeutic potentials against the immunomodulator sensitive Sarcoma 180 tumour system. The antitumour activity of Noni-ppt produced a cure rate of 25%-45% in allogeneic mice and its activity was completely abolished by the concomitant administration of specific inhibitors of macrophages (2-chloroadenosine), T cells (cyclosporine) or natural killer (NK) cells (anti-asialo GM1 antibody). Noni-ppt showed synergistic or additive beneficial effects when combined with a broad spectrum of chemotherapeutic drugs, including cisplatin, adriamycin, mitomycin-C, bleomycin, etoposide, 5- fl uorouracil, vincristine or camptothecin. It was not beneficial when combined with paclitaxel, cytosine arabinoside, or immunosuppressive anticancer drugs such as cyclophosphamide, methotrexate or 6-thioguanine. Noni-ppt also demonstrated beneficial effects when combined with the Th1 cytokine, interferon gamma, but its activity was abolished when combined with Th2 cytokines, interleukin-4 or interleukin-10, thereby suggesting that Noni-ppt induces a Th1 dominant immune status in vivo. The combination of Noni-ppt with imexon, a synthetic immunomodulator, also demonstrated beneficial effects, but not when combined with the MVE-2 copolymer, a high molecular weight immunomodulator. It was also not effective when combined with interleukin-2 or interleukin-12.
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Affiliation(s)
- Eiichi Furusawa
- Department of Pharmacology, John Burns School of Medicine, University of Hawaii, Honolulu, Hawaii, USA
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Kogut M, Rothwell L, Kaiser P. Differential effects of age on chicken heterophil functional activation by recombinant chicken interleukin-2. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2002; 26:817-830. [PMID: 12377221 DOI: 10.1016/s0145-305x(02)00040-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Interleukin-2 (IL-2) exercises an array of biological effects on many cells including the functional activation of cells of the innate immune response. Heterophils, the avian equivalent of the neutrophil, function as professional phagocytes to aid in regulation of innate host defenses. The objective of the present studies was to examine the effects of recombinant chicken IL-2 (rChIL-2) on functional activities of heterophils from chickens during the first 3 weeks after hatch. Peripheral blood heterophils were isolated and incubated with either COS cell-derived rChIL-2 or supernatants from mock-transfected COS cells. rChIL-2 had no effect on the functional activities of heterophils from day-of-hatch chickens, but significantly increased the phagocytosis and bactericidal activity of heterophils from 7- and 14-day-old chickens. rChIL-2 induced no direct stimulation of the respiratory burst by heterophils, but primed heterophils from 7- and 14-day-old birds for an enhanced respiratory burst in response to phorbol ester stimulation. Lastly, rChIL-2 had neither direct nor priming effects on heterophil degranulation. The enhancing effects on heterophil functional activity by rChIL-2 were abated by a neutralizing anti-chicken IL-2 mAb and were therefore specific for this cytokine. These results show that rChIL-2 can directly activate chicken heterophils to exert effector functions, and that heterophil activation by rChIL-2 is also an age-dependent event.
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Affiliation(s)
- Michael Kogut
- USDA-ARS, Southern Plains Agricultural Research Center, 2881 F&B Road, College Station, TX 77845, USA.
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Da'dara AA, Skelly PJ, Fatakdawala M, Visovatti S, Eriksson E, Harn DA. Comparative efficacy of the Schistosoma mansoni nucleic acid vaccine, Sm23, following microseeding or gene gun delivery. Parasite Immunol 2002; 24:179-87. [PMID: 12010483 DOI: 10.1046/j.1365-3024.2002.00453.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Sm23 is an integral membrane protein expressed widely in the human parasitic worm Schistosoma mansoni. Sm23 has already been shown to elicit protective immune responses following immunization with peptides or DNA constructs. In this study, we evaluated the immunogenicity and the protective efficacy of the Sm23 DNA vaccine using two different intradermal DNA delivery methods: microseeding and gene gun. Using both techniques, all mice immunized with the Sm23-pcDNA construct generated Sm23-specific immunoglobulin (Ig)G antibody, while mice immunized with the control plasmid, pcDNA, did not. Antibody isotypes analysis revealed that microseeding elicited mainly IgG2a and IgG2b antibodies, with relatively low levels of IgG1 and IgG3. The relative IgG1/IgG2a ratio was 0.03, indicative of a Th1 type immune response. In contrast, gene gun immunization resulted in significantly higher levels of IgG1 and IgG3. The relative IgG1/IgG2a ratio in this case was 11, indicative of a Th2 type immune response. No significant difference in the levels of IgG2b was observed. Coimmunization with plasmid DNA encoding either interleukin (IL)-12 or IL-4 by microseeding did not affect the levels of IgG1, while the levels of IgG2a and IgG2b were reduced. On the other hand, the levels of IgG3 were significantly increased by IL-4, but unchanged by IL-12. Importantly, in all experiments, the Sm23-pcDNA vaccine provided statistically significant levels of protection against challenge infection. Microseeding immunizations resulted in higher levels of protection (31-34% protection) than gene gun immunization (18% protection). This suggests that the Th1 type immune response elicited by microseeding immunization was responsible for the higher protection levels. However, the protective effect of the vaccine was not affected by coadministering plasmids encoding either IL-12 or IL-4 using the microseeding technique.
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Affiliation(s)
- Akram A Da'dara
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115, USA.
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13
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Da'dara AA, Skelly PJ, Wang MM, Harn DA. Immunization with plasmid DNA encoding the integral membrane protein, Sm23, elicits a protective immune response against schistosome infection in mice. Vaccine 2001; 20:359-69. [PMID: 11672898 DOI: 10.1016/s0264-410x(01)00374-7] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Schistosomes are helminth parasites infecting at least 200 million people worldwide. In this study, we evaluated the feasibility of using a nucleic acid vaccine to induce protective immune responses to the Schistosoma mansoni integral membrane protein Sm23. C57BL/6 mice were immunized by intramuscular injection in three separate vaccination trials. ELISA and Western Blot analyses indicated that mice immunized with a DNA plasmid construct encoding Sm23 (Sm23-pcDNA) generated specific IgG for Sm23, while sera from mice immunized with the control pcDNA plasmid did not. The vaccine elicited IgG(2a), and IgG(1) antibody isotypes. We also tested the adjuvant activity of IL-12 and IL-4 on humoral responses to Sm23. Co-immunization with plasmid encoding IL-12 did not affect the level of anti-Sm23 IgG(2a), but did reduce the IgG(1) level. In contrast, co-injection with a plasmid encoding IL-4 significantly reduced the level of anti-Sm23 IgG(2a), while the level of IgG(1) was largely unchanged. Importantly, the Sm23-pcDNA vaccine provided statistically significant levels of protection against challenge infection (21-44%, P<0.001-0.02). Co-administration of plasmids encoding either IL-12 or IL-4 did not significantly enhance this protective effect.
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Affiliation(s)
- A A Da'dara
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115, USA
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Ishii KJ, Suzuki K, Coban C, Takeshita F, Itoh Y, Matoba H, Kohn LD, Klinman DM. Genomic DNA released by dying cells induces the maturation of APCs. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:2602-7. [PMID: 11509601 DOI: 10.4049/jimmunol.167.5.2602] [Citation(s) in RCA: 192] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Mature APCs play a key role in the induction of Ag-specific immunity. This work examines whether genomic DNA released by dying cells provides a stimulus for APC maturation. Double-stranded but not single-stranded genomic DNA triggered APC to up-regulate expression of MHC class I/II and various costimulatory molecules. Functionally, dsDNA enhanced APC function in vitro and improved primary cellular and humoral immune responses in vivo. These effects were dependent on the length and concentration of the dsDNA but were independent of nucleotide sequence. The maturation of APC induced by dsDNA may promote host survival by improving immune surveillance at sites of tissue injury/infection.
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Affiliation(s)
- K J Ishii
- Section of Retroviral Immunology, Center for Biologics and Evaluation Research, Food and Drug Administration, Bethesda, MD 20892, USA
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Garren H, Ruiz PJ, Watkins TA, Fontoura P, Nguyen LT, Estline ER, Hirschberg DL, Steinman L. Combination of gene delivery and DNA vaccination to protect from and reverse Th1 autoimmune disease via deviation to the Th2 pathway. Immunity 2001; 15:15-22. [PMID: 11485734 DOI: 10.1016/s1074-7613(01)00171-6] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Using a combination of local gene delivery and tolerizing DNA vaccination, we demonstrate that codelivery of the interleukin-4 (IL-4) gene and a DNA vaccine encoding the self-peptide proteolipid protein 139-151 (PLP139-151) provides protective immunity against experimental autoimmune encephalomyelitis (EAE). We provide evidence for a mechanism whereby IL-4 expressed from the naked DNA is secreted and acts locally on autoreactive T cells via activation of STAT6 to shift their cytokine profile to T helper 2. We also show that DNA vaccines can be used to reverse established EAE by covaccination with the genes for myelin oligodendrocyte glycoprotein and IL-4. This treatment strategy combines the antigen-specific effects of DNA vaccination and the beneficial effects of local gene delivery.
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Affiliation(s)
- H Garren
- Department of Neurology and Neurological Sciences, Beckman Center for Molecular Medicine, Stanford University, Stanford, CA 94305, USA
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Abstract
The framework for regulating DNA vaccines has been in place since the first clinical trial was initiated in the mid-1990s. American and European regulatory guidance has evolved on the basis of insights provided by ongoing preclinical and clinical studies. These include analyses of the safety of DNA vaccines in normal volunteers, and recent data concerning the tissue distribution, persistence, and integration potential of DNA plasmids.
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Affiliation(s)
- H A Smith
- Office of Vaccine Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, 20892, Bethesda, MD, US
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17
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Prud'homme GJ, Lawson BR, Theofilopoulos AN. Anticytokine gene therapy of autoimmune diseases. Expert Opin Biol Ther 2001; 1:359-73. [PMID: 11727511 DOI: 10.1517/14712598.1.3.359] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Viral and nonviral gene therapy vectors have been successfully employed to deliver inflammatory cytokine inhibitors (anticytokines), or anti-inflammatory cytokines, such as transforming growth factor beta-1 (TGF-beta 1), which protect against experimental autoimmune diseases. These vectors carry the relevant genes into a variety of tissues, for either localised or systemic release of the encoded protein. Administration of cDNA encoding soluble IFN-gamma receptor (IFN-gamma R)/IgG-Fc fusion proteins, soluble TNF-alpha receptors, or IL-1 receptor antagonist (IL-1ra), protects against either lupus, various forms of arthritis, autoimmune diabetes, or other autoimmune diseases. These inhibitors, unlike many cytokines, have little or no toxic potential. Similarly, TGF-beta 1 gene therapy protects against numerous forms of autoimmunity, though its administration entails more risk than anticytokine therapy. We have relied on the injection of naked plasmid DNA into skeletal muscle, with or without enhancement of gene transfer by in vivo electroporation. Expression plasmids offer interesting advantages over viral vectors, since they are simple to produce, non-immunogenic and nonpathogenic. They can be repeatedly administered and after each treatment the encoded proteins are produced for relatively long periods, ranging from weeks to months. Moreover, soluble receptors which block cytokine action, encoded by gene therapy vectors, can be constructed from non-immunogenic self elements that are unlikely to be neutralised by the host immune response (unlike monoclonal antibodies [mAbs]), allowing long-term gene therapy of chronic inflammatory disorders.
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Affiliation(s)
- G J Prud'homme
- Department of Pathology, McGill University, Montreal, Qc, H3A2B4, Canada.
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18
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Spellberg B, Edwards JE. Type 1/Type 2 immunity in infectious diseases. Clin Infect Dis 2001; 32:76-102. [PMID: 11118387 DOI: 10.1086/317537] [Citation(s) in RCA: 577] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2000] [Revised: 08/02/2000] [Indexed: 12/17/2022] Open
Abstract
T helper type 1 (Th1) lymphocytes secrete secrete interleukin (IL)-2, interferon-gamma, and lymphotoxin-alpha and stimulate type 1 immunity, which is characterized by intense phagocytic activity. Conversely, Th2 cells secrete IL-4, IL-5, IL-9, IL-10, and IL-13 and stimulate type 2 immunity, which is characterized by high antibody titers. Type 1 and type 2 immunity are not strictly synonymous with cell-mediated and humoral immunity, because Th1 cells also stimulate moderate levels of antibody production, whereas Th2 cells actively suppress phagocytosis. For most infections, save those caused by large eukaryotic pathogens, type 1 immunity is protective, whereas type 2 responses assist with the resolution of cell-mediated inflammation. Severe systemic stress, immunosuppression, or overwhelming microbial inoculation causes the immune system to mount a type 2 response to an infection normally controlled by type 1 immunity. In such cases, administration of antimicrobial chemotherapy and exogenous cytokines restores systemic balance, which allows successful immune responses to clear the infection.
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Affiliation(s)
- B Spellberg
- Department of Internal Medicine, Harbor-University of California Los Angeles Medical Center, Torrance, CA 90509, USA.
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Khanna AK, Hosenpud JD. In vitro and in vivo transfection of p21 gene enhances cyclosporin A-mediated inhibition of lymphocyte proliferation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:1882-8. [PMID: 10925268 DOI: 10.4049/jimmunol.165.4.1882] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Cyclosporine has potent antiproliferative properties, some of which may be via the induction of the cyclin inhibitor p21. In this study, we describe the effects of in vitro and in vivo transfection of p21 in lymphoid and nonlymphoid cells. For in vitro studies, p21 sense plasmid DNA was transfected in A-549 cells (lung adenocarcinoma cell line) and Jurkat cells (human lymphoid cell line). This in vitro transfection of p21 resulted in the inhibition of spontaneous and mitogen-induced cellular proliferation ([3H]thymidine uptake) and also augmented the antiproliferative effects of cyclosporine. In vivo transfection of p21 was accomplished in mice via the i.m. injection of p21 sense plasmid DNA complexed with cationic lipids. As was the case in the cell lines, p21 mRNA was augmented in heart, lung, liver, and spleen 7 days after i.m. injection of p21 sense plasmid DNA. The mitogen (anti-CD3)-induced proliferation of splenocytes from p21-overexpressing mice was significantly decreased, and again this effect was augmented by cotreatment with cyclosporine. These novel findings demonstrate the potential of targeting the cell cycle directly to inhibit alloimmune activation in organ transplantation. This may serve as an alternate strategy to induce immunosuppression, perhaps with less toxicity than that which is seen with conventional immunosuppressive agents.
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Affiliation(s)
- A K Khanna
- The Cardiovascular Research Center, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
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Abstract
The development and widespread use of vaccines against infectious agents have been a great triumph of medical science. One reason for the success of currently available vaccines is that they are capable of inducing long-lived antibody responses, which are the principal agents of immune protection against most viruses and bacteria. Despite these successes, vaccination against intracellular organisms that require cell-mediated immunity, such as the agents of tuberculosis, malaria, leishmaniasis, and human immunodeficiency virus infection, are either not available or not uniformly effective. Owing to the substantial morbidity and mortality associated with these diseases worldwide, an understanding of the mechanisms involved in generating long-lived cellular immune responses has tremendous practical importance. For these reasons, a new form of vaccination, using DNA that contains the gene for the antigen of interest, is under intensive investigation, because it can engender both humoral and cellular immune responses. This review focuses on the mechanisms by which DNA vaccines elicit immune responses. In addition, a list of potential applications in a variety of preclinical models is provided.
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Affiliation(s)
- S Gurunathan
- Laboratory of Clinical Investigation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
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21
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Prud'homme GJ. Gene therapy of autoimmune diseases with vectors encoding regulatory cytokines or inflammatory cytokine inhibitors. J Gene Med 2000; 2:222-32. [PMID: 10953913 DOI: 10.1002/1521-2254(200007/08)2:4<222::aid-jgm117>3.0.co;2-p] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Gene therapy offers advantages for the immunotherapeutic delivery of cytokines or their inhibitors. After gene transfer, these mediators are produced at relatively constant, non-toxic levels and sometimes in a tissue-specific manner, obviating limitations of protein administration. Therapy with viral or nonviral vectors is effective in several animal models of autoimmunity including Type 1 diabetes mellitus (DM), experimental allergic encephalomyelitis (EAE), systemic lupus erythematosus (SLE), colitis, thyroiditis and various forms of arthritis. Genes encoding transforming growth factor beta, interleukin-4 (IL-4) and IL-10 are most frequently protective. Autoimmune/ inflammatory diseases are associated with excessive production of inflammatory cytokines such as IL-1, IL-12, tumor necrosis factor alpha (TNFalpha) and interferon gamma (IFNgamma). Vectors encoding inhibitors of these cytokines, such as IL-1 receptor antagonist, soluble IL-1 receptors, IL-12p40, soluble TNFalpha receptors or IFNgamma-receptor/IgG-Fc fusion proteins are protective in models of either arthritis, Type 1 DM, SLE or EAE. We use intramuscular injection of naked plasmid DNA for cytokine or anticytokine therapy. Muscle tissue is accessible, expression is usually more persistent than elsewhere, transfection efficiency can be increased by low-voltage in vivo electroporation, vector administration is simple and the method is inexpensive. Plasmids do not induce neutralizing immunity allowing repeated administration, and are suitable for the treatment of chronic immunological diseases.
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Affiliation(s)
- G J Prud'homme
- Department of Pathology, McGill University, Montreal, Quebec, Canada.
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Song K, Chang Y, Prud'homme GJ. Regulation of T-helper-1 versus T-helper-2 activity and enhancement of tumor immunity by combined DNA-based vaccination and nonviral cytokine gene transfer. Gene Ther 2000; 7:481-92. [PMID: 10757021 DOI: 10.1038/sj.gt.3301123] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Intramuscular (i.m.) injections of a plasmid encoding human carcinoembryonic antigen (CEA) elicited both humoral and cellular immune responses in mice, but only partial inhibition of the growth of transplanted syngeneic CEA-positive P815 tumor cells (CEA/P815). Coinjection of the CEA vector with a vector encoding either interferon-gamma (IFN gamma) or IL-12 promoted IgG2a isotype anti-CEA antibody production, anti-CEA/P815 CTL activity and greater resistance to CEA/P815 tumor challenge. As well, CEA/P815-stimulated IFN gamma secretion in vitro was increased, but IL-4 diminished, consistent with a T-helper type 1 (Th1) response. In contrast, coinjection of the CEA vector with an IL-4 vector increased IgG1 production, but reduced CTL activity and resistance to tumor challenge. The latter treatment inhibited CEA/P815-dependent IFN gamma production but enhanced IL-4 secretion, consistent with a Th type 2 (Th2) response. Antitumor immunity was enhanced when the CEA and IL-12 plasmids were coinjected at the same muscle site, but not at separate sites despite increased serum IL-12 levels. Though the tumor cells expressed neomycin phosphotransferase, mice immunized with vectors encoding that protein (without CEA) were not protected against tumor growth, and produced no CTLs except for low levels when coinjected with an IL-12 vector. Thus, we show that immunity elicited by DNA vaccination against CEA can be biased to a protective type (high Th1 and CTL activity) or nonprotective type (high Th2 and low CTL activity) by i.m. coinjection of cytokine-expressing plasmids. IL-12 appears to act locally, but not systemically, through an adjuvant effect.
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Affiliation(s)
- K Song
- Department of Pathology, McGill University, Montreal, Quebec, Canada
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Ishii KJ, Weiss WR, Klinman DM. Prevention of neonatal tolerance by a plasmid encoding granulocyte-macrophage colony stimulating factor. Vaccine 1999; 18:703-10. [PMID: 10547430 DOI: 10.1016/s0264-410x(99)00267-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A plasmid DNA vaccine encoding the circumsporozoite protein of malaria (pCSP) induces protective immunity in adult mice but persistent tolerance when administered to neonates. In an effort to improve antigen presenting cell (APC) function in newborns, we co-administered pCSP with a plasmid encoding granulocyte-macrophage colony stimulating factor (pGMCSF). This combination of plasmids prevented the development of neonatal tolerance, instead eliciting a primary IgG anti-CSP immune response. Mice primed as neonates and boosted as adults mounted anamnestic responses characterized by high serum antibody titers, cytotoxic T-cell activity and antigen-specific interferon gamma (IFNgamma) production. Neonatal administration of pGMCSF accelerated the maturation of local dendritic cells, suggesting that APC function plays a key role in determining whether tolerance or immunity results from neonatal exposure to antigen.
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Affiliation(s)
- K J Ishii
- Retroviral Immunology Section, Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892, USA
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Chang Y, Prud'homme GJ. Intramuscular administration of expression plasmids encoding interferon-gamma receptor/IgG1 or IL-4/IgG1 chimeric proteins protects from autoimmunity. J Gene Med 1999; 1:415-23. [PMID: 10753067 DOI: 10.1002/(sici)1521-2254(199911/12)1:6<415::aid-jgm66>3.0.co;2-b] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Interferon gamma (IFNgamma) is an inflammatory cytokine that promotes autoimmune insulitis and diabetes in NOD mice, while interleukin-4 (IL-4) is protective. We constructed plasmids encoding either an IFNgamma receptor/IgG1 (IFNgammaR/IgG1) chimeric protein which inhibits IFNgamma, or an IL-4/IgG1 chimeric protein with IL-4 activity, for therapeutic gene transfer into NOD mice. METHODS Murine IFNgammaR/IgG1 and IL-4/IgG1 cDNA segments were cloned into the VICAL VR1255 expression plasmid. Naked plasmid DNA was injected i.m. into young NOD mice, which were then observed for development of insulitis and diabetes. RESULTS After transient transfection of COS-7 cells, IFNgammaR/IgG1 and IL-4/IgG1 fusion proteins are secreted in vitro as disulfide-linked homodimers, with the expected biological activity. Intramuscular injection of these vectors results in the production of the respective fusion proteins locally in muscle. In serum, the IFNgammaR/IgG1 protein is present at >200 ng/ml over 130 days after the last of five DNA injections, but IL-4/IgG1 is undetectable in our assays (<10 pg/ml) at all time points. Both vectors protect NOD mice from autoimmune insulitis and diabetes, but the IL-4/IgG1 vector is more effective. Neutralization of IFNgamma with IFNgammaR/IgG1 was most protective when treatment was begun early (3 weeks of age). CONCLUSION Gene therapy by i.m. injection of these plasmids protects NOD mice from autoimmunity, and the IL-4/IgG1 vector is more effective despite low circulating protein levels. These chimeric proteins consist of nonimmunogenic self elements and are suitable for long-term therapy of autoimmune disorders.
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Affiliation(s)
- Y Chang
- Department of Pathology, McGill University, Montreal, Quebec, Canada
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25
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Piccirillo CA, Prud'homme GJ. Prevention of experimental allergic encephalomyelitis by intramuscular gene transfer with cytokine-encoding plasmid vectors. Hum Gene Ther 1999; 10:1915-22. [PMID: 10466625 DOI: 10.1089/10430349950017275] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Antiinflammatory cytokines such as transforming growth factor beta1 (TGF-beta1) and interleukin 4 (IL-4) can protect from autoimmune diseases. To study the immunoregulatory effects of these cytokines in vivo, we used a method of gene therapy that permits continuous cytokine delivery over a period of weeks. We injected naked plasmid DNA expression vectors encoding either TGF-beta1 (pVR-TGF-beta1) or an IL-4-IgG1 chimeric protein (pVR-IL-4-IgG1) intramuscularly. This resulted in production of TGF-beta1 or IL-4-IgG1, respectively, and protection from myelin basic protein (MBP)-induced experimental allergic encephalomyelitis (EAE). TGF-beta1 gene delivery had pronounced downregulatory effects on T cell proliferation and production of interferon gamma (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha), on in vitro restimulation with MBP. IL-4-IgG1 vector administration also suppressed these responses, although much less than TGF-beta1, and enhanced secretion of endogenous IL-4. Therapy resulted in a significant decrease in the severity of histopathologic inflammatory lesions. In the CNS, treatment with either vector suppressed IL-12 and IFN-gamma mRNA expression, while IL-4 and TGF-beta1 mRNA levels were increased compared with control mice. Thus, cytokine plasmid treatment appeared to inhibit MBP-specific pathogenic Thl responses, while enhancing endogenous secretion of protective cytokines. We demonstrate that gene therapy with these vectors is an effective therapeutic strategy for EAE.
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Affiliation(s)
- C A Piccirillo
- Department of Pathology and Center for Clinical Immunobiology and Transplantation, McGill University, Montreal, Quebec, Canada
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Klinman DM, Verthelyi D, Takeshita F, Ishii KJ. Immune recognition of foreign DNA: a cure for bioterrorism? Immunity 1999; 11:123-9. [PMID: 10485647 DOI: 10.1016/s1074-7613(00)80087-4] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- D M Klinman
- Section of Retroviral Immunology, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892, USA.
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