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Pagliari S, Dema B, Sanchez-Martinez A, Montalvo Zurbia-Flores G, Rollier CS. DNA Vaccines: History, Molecular Mechanisms and Future Perspectives. J Mol Biol 2023; 435:168297. [PMID: 37797831 DOI: 10.1016/j.jmb.2023.168297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/22/2023] [Accepted: 09/28/2023] [Indexed: 10/07/2023]
Abstract
The history of DNA vaccine began as early as the 1960s with the discovery that naked DNA can transfect mammalian cells in vivo. In 1992, the evidence that such transfection could lead to the generation of antigen-specific antibody responses was obtained and supported the development of this technology as a novel vaccine platform. The technology then attracted immense interest and high hopes in vaccinology, as evidence of high immunogenicity and protection against virulent challenges accumulated from several animal models for several diseases. In particular, the capacity to induce T-cell responses was unprecedented in non-live vaccines. However, the technology suffered its major knock when the success in animals failed to translate to humans, where DNA vaccine candidates were shown to be safe but remained poorly immunogenic, or not associated with clinical benefit. Thanks to a thorough exploration of the molecular mechanisms of action of these vaccines, an impressive range of approaches have been and are currently being explored to overcome this major challenge. Despite limited success so far in humans as compared with later genetic vaccine technologies such as viral vectors and mRNA, DNA vaccines are not yet optimised for human use and may still realise their potential.
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Affiliation(s)
- Sthefany Pagliari
- School of Biosciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK; Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Barbara Dema
- Pandemic Science Institute, Institute of Developmental and Regenerative Medicine (IDRM), University of Oxford, Oxford, UK
| | | | | | - Christine S Rollier
- School of Biosciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK.
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Maciel M, Cruz FDSP, Cordeiro MT, da Motta MA, Cassemiro KMSDM, Maia RDCC, de Figueiredo RCBQ, Galler R, Freire MDS, August JT, Marques ETA, Dhalia R. A DNA vaccine against yellow fever virus: development and evaluation. PLoS Negl Trop Dis 2015; 9:e0003693. [PMID: 25875109 PMCID: PMC4395287 DOI: 10.1371/journal.pntd.0003693] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 03/10/2015] [Indexed: 11/30/2022] Open
Abstract
Attenuated yellow fever (YF) virus 17D/17DD vaccines are the only available protection from YF infection, which remains a significant source of morbidity and mortality in the tropical areas of the world. The attenuated YF virus vaccine, which is used worldwide, generates both long-lasting neutralizing antibodies and strong T-cell responses. However, on rare occasions, this vaccine has toxic side effects that can be fatal. This study presents the design of two non-viral DNA-based antigen formulations and the characterization of their expression and immunological properties. The two antigen formulations consist of DNA encoding the full-length envelope protein (p/YFE) or the full-length envelope protein fused to the lysosomal-associated membrane protein signal, LAMP-1 (pL/YFE), aimed at diverting antigen processing/presentation through the major histocompatibility complex II precursor compartments. The immune responses triggered by these formulations were evaluated in H2b and H2d backgrounds, corresponding to the C57Bl/6 and BALB/c mice strains, respectively. Both DNA constructs were able to induce very strong T-cell responses of similar magnitude against almost all epitopes that are also generated by the YF 17DD vaccine. The pL/YFE formulation performed best overall. In addition to the T-cell response, it was also able to stimulate high titers of anti-YF neutralizing antibodies comparable to the levels elicited by the 17DD vaccine. More importantly, the pL/YFE vaccine conferred 100% protection against the YF virus in intracerebrally challenged mice. These results indicate that pL/YFE DNA is an excellent vaccine candidate and should be considered for further developmental studies.
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Affiliation(s)
- Milton Maciel
- Johns Hopkins University, School of Medicine, Department of Pharmacology & Molecular Sciences, Baltimore, Maryland, United States of America
| | - Fábia da Silva Pereira Cruz
- Oswaldo Cruz Foundation (FIOCRUZ), Aggeu Magalhães Research Centre, Department of Virology, Laboratório de Virologia e Terapia Experimental (LAVITE), Universidade Federal de Pernambuco (UFPE), University City, Recife, Pernambuco, Brazil
| | - Marli Tenório Cordeiro
- Oswaldo Cruz Foundation (FIOCRUZ), Aggeu Magalhães Research Centre, Department of Virology, Laboratório de Virologia e Terapia Experimental (LAVITE), Universidade Federal de Pernambuco (UFPE), University City, Recife, Pernambuco, Brazil
- Health Secretariat of the State of Pernambuco, Central Public Health Laboratory-LACEN, Boa Vista, Recife, Pernambuco, Brazil
| | - Márcia Archer da Motta
- Oswaldo Cruz Foundation (FIOCRUZ), Oswaldo Cruz Institute, Bio-Manguinhos, Laboratório de Tecnologia Virológica (LATEV), Manguinhos, Rio de Janeiro, Brazil
| | - Klécia Marília Soares de Melo Cassemiro
- Oswaldo Cruz Foundation (FIOCRUZ), Aggeu Magalhães Research Centre, Department of Virology, Laboratório de Virologia e Terapia Experimental (LAVITE), Universidade Federal de Pernambuco (UFPE), University City, Recife, Pernambuco, Brazil
| | - Rita de Cássia Carvalho Maia
- Federal Rural University of Pernambuco, Department of Veterinary Medicine, Dois Irmãos, Recife, Pernambuco, Brazil
| | - Regina Célia Bressan Queiroz de Figueiredo
- Oswaldo Cruz Foundation (FIOCRUZ), Aggeu Magalhães Research Centre, Department of Virology, Laboratório de Virologia e Terapia Experimental (LAVITE), Universidade Federal de Pernambuco (UFPE), University City, Recife, Pernambuco, Brazil
| | - Ricardo Galler
- Oswaldo Cruz Foundation (FIOCRUZ), Oswaldo Cruz Institute, Bio-Manguinhos, Laboratório de Tecnologia Virológica (LATEV), Manguinhos, Rio de Janeiro, Brazil
| | - Marcos da Silva Freire
- Oswaldo Cruz Foundation (FIOCRUZ), Oswaldo Cruz Institute, Bio-Manguinhos, Laboratório de Tecnologia Virológica (LATEV), Manguinhos, Rio de Janeiro, Brazil
| | - Joseph Thomas August
- Johns Hopkins University, School of Medicine, Department of Pharmacology & Molecular Sciences, Baltimore, Maryland, United States of America
| | - Ernesto T. A. Marques
- Johns Hopkins University, School of Medicine, Department of Pharmacology & Molecular Sciences, Baltimore, Maryland, United States of America
- Oswaldo Cruz Foundation (FIOCRUZ), Aggeu Magalhães Research Centre, Department of Virology, Laboratório de Virologia e Terapia Experimental (LAVITE), Universidade Federal de Pernambuco (UFPE), University City, Recife, Pernambuco, Brazil
- University of Pittsburgh, Center for Vaccine Research, Pittsburgh, Pennsylvania, United States of America
| | - Rafael Dhalia
- Oswaldo Cruz Foundation (FIOCRUZ), Aggeu Magalhães Research Centre, Department of Virology, Laboratório de Virologia e Terapia Experimental (LAVITE), Universidade Federal de Pernambuco (UFPE), University City, Recife, Pernambuco, Brazil
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Abstract
Transmitted by the Aedes aegypti mosquito, the dengue virus is the etiological agent of dengue fever, dengue hemorrhagic fever and dengue shock syndrome, and, as such, is a significant factor in the high death rate found in most tropical and subtropical areas of the world. Dengue diseases are not only a health burden to developing countries, but pose an emerging problem worldwide. The immunopathological mechanisms appear to include a complex series of immune responses. A rapid increase in the levels of cytokines and chemical mediators during dengue disease plays a key role in inducing plasma leakage, shock and hemorrhagic manifestations. Currently, there are no vaccines available against dengue virus, although several tetravalent live-attenuated dengue vaccines are in clinical phases I or II, and prevention through vaccination has become a major priority on the agendas of the World Health Organization and of national ministries of health and military organizations. An alternative to vaccines is found in therapeutic-based approaches. Understanding the molecular mechanisms of viral replication has led to the development of potential drugs, and new molecular viral targets for therapy are emerging. The NS3 protease domain of the NS3 protein is responsible for processing the viral polyprotein and its inhibition is one of the principal aims of pharmacological therapy. This review is an overview of the progress made against dengue virus; in particular, it examines the unique properties--structural and functional--of the NS3 protease for the treatment of dengue virus infections by the inhibition of viral polyprotein processing.
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Affiliation(s)
- Sonia Melino
- Department of Chemical Science and Technology, University of Rome Tor Vergata, Italy.
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Sharma VK, Klibanov AM. Moisture-induced aggregation of lyophilized DNA and its prevention. Pharm Res 2006; 24:168-75. [PMID: 17041790 DOI: 10.1007/s11095-006-9138-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2006] [Accepted: 07/27/2006] [Indexed: 11/28/2022]
Abstract
PURPOSE To investigate the moisture-induced aggregation (i.e., a loss of solubility in water) of DNA in a solid state and to develop rational strategies for its prevention. METHODS Lyophilized calf thymus DNA was exposed to relative humidity (RH) levels from 11% to 96% at 55 degrees C. Following a 24-h incubation under these stressed conditions, the solubility of DNA in different aqueous solutions and the water uptake of DNA were determined. The effects of solution pH and NaCl concentration and the presence of excipients (dextran and sucrose) on the subsequent moisture-induced aggregation of DNA were examined. The extent of this aggregation was compared with that of a supercoiled plasmid DNA. RESULTS Upon a 24-h incubation at 55 degrees C, calf thymus DNA underwent a major moisture-induced aggregation reaching a maximum at a 60% RH; in contrast, the single-stranded DNA exhibited the maximal aggregation at a 96% RH. Moisture uptake and aqueous solubility studies revealed that the aggregation was primarily due to formation of inter-strand hydrogen bonds. Aggregation of DNA also proceeded at 37 degrees C, albeit at a slower rate. Solution pH and NaCl concentration affected DNA aggregation only at higher RH levels. This aggregation was markedly reduced by co-lyophilization with dextran or sucrose (but not with PEG). The aggregation pattern of a supercoiled plasmid DNA was similar to that of its linear calf thymus counterpart. CONCLUSIONS The moisture-induced aggregation of lyophilized DNA is caused mainly by non-covalent cross-links between disordered, single-stranded regions of DNA. At high RH levels, renaturation and aggregation of DNA compete with each other. The aggregation is minimized at low RH levels, at optimal solution pH and salt concentration prior to lyophilization, and by co-lyophilizing with excipients capable of forming multiple hydrogen bonds, e.g., dextran and sucrose.
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Affiliation(s)
- Vikas K Sharma
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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Ivanovska N, Tchorbanov A, Prechl J, Maximova V, Voynova E, Vassilev TL. Immunization with a DNA chimeric molecule encoding a hemagglutinin peptide and a scFv CD21-specific antibody fragment induces long-lasting IgM and CTL responses to influenza virus. Vaccine 2006; 24:1830-7. [PMID: 16289708 DOI: 10.1016/j.vaccine.2005.10.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2005] [Revised: 10/05/2005] [Accepted: 10/13/2005] [Indexed: 11/20/2022]
Abstract
Killed viral vaccines are known to induce primarily antibody responses. By contrast DNA vaccination using naked DNA encoding viral antigens induces both humoral and cellular immune responses. Various approaches have been used to construct DNA vaccines with build-in adjuvanticity. We hypothesized that sequences encoding a common epitope of influenza A virus hemagglutinin jointed to sequences encoding a single-chain variable fragment (scFv) antibody fragment to a costimulatory B cell surface receptor would result in the in vivo expression of a chimeric viral peptide with increased immunogenicity. Such a hybrid DNA molecule was constructed by us, encoding a T and B cell epitope-containing influenza hemagglutinin peptide and a scFv antibody fragment binding to mouse complement receptors I and II (CR1 and CR2). A single immunization with a plasmid containing the described construct induced a strong anti-influenza cytotoxic response lasting for more than six months and a weak antibody response.
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MESH Headings
- Adjuvants, Immunologic
- Animals
- Antibodies, Viral/blood
- Cytotoxicity, Immunologic
- Enzyme-Linked Immunosorbent Assay
- Female
- Hemagglutination Inhibition Tests
- Hemagglutinin Glycoproteins, Influenza Virus/genetics
- Hemagglutinin Glycoproteins, Influenza Virus/immunology
- Immunoglobulin G/blood
- Immunoglobulin M/blood
- Immunoglobulin Variable Region/genetics
- Influenza A virus/immunology
- Influenza Vaccines/immunology
- Mice
- Mice, Inbred BALB C
- Receptors, Complement/immunology
- Receptors, Complement 3d/immunology
- T-Lymphocytes, Cytotoxic/immunology
- Vaccination
- Vaccines, DNA/administration & dosage
- Vaccines, DNA/genetics
- Vaccines, DNA/immunology
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Affiliation(s)
- Nina Ivanovska
- Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria.
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LI GX, QIU HJ, HAN CG, HAN LX, ZHOU YJ, CHEN Y, LI JC, TONG GZ. Vaccination of Plasmid DNA Encoding Somatostatin Gene Fused with GP5 Gene of Porcine Reproductive and Respiratory Syndrome Virus Induces Anti-GP5 Antibodies and Promotes Growth Performance in Immunized Pigs. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/s1671-2927(06)60044-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Konishi E, Kosugi S, Imoto JI. Dengue tetravalent DNA vaccine inducing neutralizing antibody and anamnestic responses to four serotypes in mice. Vaccine 2005; 24:2200-7. [PMID: 16316713 DOI: 10.1016/j.vaccine.2005.11.002] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2005] [Revised: 09/08/2005] [Accepted: 11/01/2005] [Indexed: 01/08/2023]
Abstract
We developed a dengue tetravalent DNA vaccine consisting of plasmids expressing premembrane and envelope genes of each of four serotypes of dengue viruses. BALB/c mice immunized twice with the tetravalent vaccine at a dose of 100 microg (25 microg for each serotype) using a needle-free jet injector developed neutralizing antibodies against all serotypes. There was no interference among the four components included in this combination vaccine. Tetravalent vaccine-immunized mice showed anamnestic neutralizing antibody responses following challenge with each dengue serotype: responses to challenges from serotypes different to those used for neutralization tests were also induced.
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Affiliation(s)
- Eiji Konishi
- Department of Health Sciences, Kobe University School of Medicine, 7-10-2 Tomogaoka, Suma-ku, Kobe 654-0142, Japan.
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Abstract
Dengue is one of the most important mosquito-borne viral disease causing dengue fever and/or dengue shock syndrome/haemorrhagic fever. In some reports, the non-structural protein 1 (NS1) has been identified as a promising antigen for the development of vaccines against dengue virus (DENV). Apparently, it can elicit a protective antibody response with complement-fixing activities. In order to investigate the potential of a DNA vaccine based on the NS1 protein against DENV, we used the plasmid pcTPANS1, which contains the secretory signal sequence derived from human tissue plasminogen activator (t-PA) fused to the full length of the DENV-2 NS1 gene. All Balb/c mice intramuscularly inoculated with the pcTPANS1 presented high levels of NS1-specifc antibodies. Vaccinated animals were challenged with intracerebral DENV-2 virus inoculations and a 100% survival was observed. In general, results demonstrate that the pcTPANS1 plasmid is able to induce protection in mice, and then may be used as a vaccination approach against DENV in further assays.
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Affiliation(s)
- S M Costa
- Laboratório de Imunopatologia, Departamento de Bioquímica e Biologia Molecular, IOC, Fundação Oswaldo Cruz (FIOCRUZ), Av. Brazil 4365, Pav. Leonidas Deane, Sala 204, Rio de Janeiro, RJ CEP 21045-900, Brazil
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Costa SM, Paes MV, Barreto DF, Pinhão AT, Barth OM, Queiroz JLS, Armôa GRG, Freire MS, Alves AMB. Protection against dengue type 2 virus induced in mice immunized with a DNA plasmid encoding the non-structural 1 (NS1) gene fused to the tissue plasminogen activator signal sequence. Vaccine 2005; 24:195-205. [PMID: 16122850 DOI: 10.1016/j.vaccine.2005.07.059] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2005] [Accepted: 07/25/2005] [Indexed: 12/01/2022]
Abstract
Dengue is one of the most important arboviral diseases in humans, and although efforts over the last decades have dealt with the development of a vaccine, this vaccine is not available yet. In order to evaluate the potential of a DNA vaccine based on the non-structural 1 (NS1) protein against dengue virus (DENV), we constructed the pcTPANS1 plasmid which contains the secretory signal sequence derived from human tissue plasminogen activator (t-PA) fused to the full length of the DENV-2 NS1 gene. Results indicate that pcTPANS1 promotes correct expression of NS1 in eukaryotic cells and drives secretion of the recombinant protein to the surrounding medium in a dimeric form. Balb/c mice, intramuscularly inoculated with this plasmid, presented high levels of antibodies, recognizing mainly surface-exposed conformational epitopes present in the NS1 protein expressed by insect cells. Long-term antibody response was observed in animals 56 weeks after the first plasmid inoculation, and a rapid, efficient secondary response was observed after a DNA boost. Vaccinated animals were challenged against DENV-2 in two murine models, based on intracerebral (i.c.) and intraperitoneal (i.p.) virus inoculations, and in both cases, pcTPANS1-immunized mice were protected. Overall, these results provide further support for the use of such a plasmid in a possible approach for the development of a vaccine against DENV.
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Affiliation(s)
- Simone M Costa
- Department of Biochemistry and Molecular Biology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Av. Brazil 4365, Pav. Leonidas Deane, sala 204, Rio de Janeiro, RJ, CEP 21040-900, Brazil
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Schiltz JG, Salzer U, Mohajeri MH, Franke D, Heinrich J, Pavlovic J, Wollmer MA, Nitsch RM, Moelling K. Antibodies from a DNA peptide vaccination decrease the brain amyloid burden in a mouse model of Alzheimer's disease. J Mol Med (Berl) 2005; 82:706-14. [PMID: 15241501 DOI: 10.1007/s00109-004-0570-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The neuropathology of Alzheimer's disease(AD) is characterized by the accumulation of amyloid peptide Abeta in the brain derived from proteolytic cleavage of the amyloid precursor protein (APP). Vaccination of mice with plasmid DNA coding for the human Abeta42 peptide together with low doses of preaggregated peptide induced antibodies with detectable titers after only 2 weeks. One serum was directed against the four aminoterminal amino acids DAEF and differs from previously described ones. Both immune sera and monoclonal antibodies solubilized preformed aggregates of Abeta42 in vitro and recognized amyloid plaques in brain sections of mice transgenic for human APP. Passive immunization of transgenic AD mice caused a significant and rapid reduction in brain amyloid plaques within 24 h. The combined DNA peptide vaccine may prove useful for active immunization with few inoculations and low peptide dose which may prevent the recently described inflammatory reactions inpatients. The monoclonal antibodies are applicable for passive immunization studies and may lead to a therapy of AD.
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Affiliation(s)
- Jan G Schiltz
- Institute if Medical Virology, University of Zurich, Gloriastrasse 30, 8028 Zurich, Switzerland
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Keyser J, Schultz J, Ladell K, Elzaouk L, Heinzerling L, Pavlovic J, Moelling K. IP-10-encoding plasmid DNA therapy exhibits anti-tumor and anti-metastatic efficiency. Exp Dermatol 2004; 13:380-90. [PMID: 15186325 DOI: 10.1111/j.0906-6705.2004.00191.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report here that the interferon-induced protein of 10 kDa (IP-10 or CXCL10) elicits strong anti-tumor and anti-metastatic responses in mice when administered by plasmid DNA. Intratumoral but not intramuscular IP-10 DNA inoculation resulted in reduced tumor formation of malignant melanoma (B16F10) and Lewis lung carcinoma (LL/2) in C57BL/6 mice. In addition, plasmid DNA-encoding IP-10 substantially reduced the establishment of metastases when injected systemically by the intramuscular route. In contrast to the primary tumor model, the anti-metastatic effect of DNA-encoding IP-10 was primarily mediated by NK cells. Compared to DNA-encoding interleukin-12 (IL-12), therapy with DNA-encoding IP-10 exhibits lower efficacy against primary melanoma tumors but equivalent efficacy against primary Lewis lung tumors and against B16F10 lung metastasis formation. Co-administration of DNA-encoding IP-10 and IL-12 enhanced the anti-tumor activity of IL-12 in the lung metastasis model but had little effect in the local treatment of established subcutaneous tumors. Interestingly, treatment of nude mice lacking T lymphocytes with DNA-encoding IP-10 or IL-12 still resulted in a pronounced reduction of tumor growth or metastasis formation.
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Affiliation(s)
- Johanna Keyser
- Institute of Medical Virology, University of Zurich, Gloriastr., Zurich, Switzerland
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Abstract
The mean age of patients at both first HIV detection and AIDS diagnosis is progressively rising over time. However, reliable epidemiological estimates, clinical data or controlled therapeutic and outcome figures are lacking for elderly patients, especially with regard to laboratory and clinical response to antiretroviral therapy, treatment tolerability, drug-drug interactions, short- and long-term toxicity, and interactions with underlying illnesses and concurrent pharmacological treatment. In fact, the large majority of randomised, controlled trials evaluating and comparing new antiretroviral drugs or anti-HIV therapeutic strategies, as well as antimicrobial treatment or chemoprophylaxis of HIV-related complications, either excluded patients with advanced age and/or concurrent disorders or did not offer substudies or detailed data analysis focusing on older patients compared with younger ones. The life expectancy of HIV-infected persons receiving highly active antiretroviral therapy (HAART) is now extended (approaching that of the general population), so that the definition of AIDS has lost its epidemiological and clinical significance thanks to the immune reconstitution resulting from potent antiretroviral therapy. However, an ever-increasing number of individuals aged > or =50 years with HIV infection is expected in the coming years, as a result of both increased survival of patients with treated disease and delayed recognition of individuals with occult HIV disease. The limited data available about combined antiretroviral therapy in the elderly seem to show an overlapping virological success rate but a slower and blunted immune recovery compared with younger patients. Thymic output, however, seems somewhat preserved even in adulthood and may contribute to the reconstitution of most of the quantitative and functional T cell abnormalities caused by HIV disease. More attention must be paid to underlying end-organ disorders, as well as expected pharmacological interactions and combined drug toxicity that may interfere with HAART efficacy and patients' compliance with recommended regimens and could lead to increased adverse effects. The available guidelines for antiretroviral treatment and therapy and prophylaxis of AIDS-related illnesses should be regularly updated and should include problems related to HIV disease in an aging population. Specific trials or substudies focusing on older people are warranted to obtain controlled data on all issues of antiretroviral therapy in the elderly, including time and mode of initiation, and modification and salvage HAART regimens. Antiretroviral drug dosage adjustment to take into account underlying pathological conditions or other pharmacological treatments is another emerging issue.
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Affiliation(s)
- Roberto Manfredi
- Department of Clinical and Experimental Medicine, Division of Infectious Diseases, University of Bologna, S. Orsola Hospital, Via Massarenti 11, I-40138 Bologna, Italy.
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Beckebaum S, Cicinnati VR, Gerken G. DNA-based immunotherapy: potential for treatment of chronic viral hepatitis? Rev Med Virol 2002; 12:297-319. [PMID: 12211043 DOI: 10.1002/rmv.359] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Persistent HBV and HCV infection represent major causes of chronic liver disease with a high risk of progression to liver cirrhosis and hepatocellular carcinoma (HCC). Conventional protein-based vaccines are highly efficacious in preventing HBV infection; whereas in therapeutic settings with chronically infected patients, results have been disappointing. Prophylactic vaccination against HCV infection has not yet been achieved due to many impediments including frequent spontaneous mutations of the virus with escape from immune system control. Using animal models it has been demonstrated that DNA-based immunisation strategies may overcome this problem because of their potential to induce immunity against multiple viral epitopes. DNA-based vaccines mimic the effect of live attenuated viral vaccines, eliciting cell mediated immunity in addition to inducing humoral responses. Efficacy may further be improved by addition of DNA encoding immunomodulatory cytokines and more recently, direct genetic modulation of antigen-presenting cells, such as dendritic cells (DC), has been shown to increase antigen-specific immune responses. This review focuses on immunological aspects of chronic HBV and HCV infection and on the potential of DNA- and DC-based vaccines for the treatment of chronic viral hepatitis.
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Affiliation(s)
- Susanne Beckebaum
- Department of Gastroenterology and Hepatology, University of Essen, Germany
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Abstract
Development of a prophylactic human immunodeficiency virus type 1 (HIV-1) vaccine is a leading priority in biomedical research. Much of this work has been done with the nonhuman primate model of AIDS. In a historical context, vaccine studies, which use this model, are summarized and discussed.
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Affiliation(s)
- Stephen M Smith
- Saint Michael's Medical Center and The New Jersey Medical School - UMDNJ, Newark, NJ, USA.
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