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STxB as an Antigen Delivery Tool for Mucosal Vaccination. Toxins (Basel) 2022; 14:toxins14030202. [PMID: 35324699 PMCID: PMC8948715 DOI: 10.3390/toxins14030202] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/03/2022] [Accepted: 03/07/2022] [Indexed: 12/31/2022] Open
Abstract
Immunotherapy against cancer and infectious disease holds the promise of high efficacy with minor side effects. Mucosal vaccines to protect against tumors or infections disease agents that affect the upper airways or the lung are still lacking, however. One mucosal vaccine candidate is the B-subunit of Shiga toxin, STxB. In this review, we compare STxB to other immunotherapy vectors. STxB is a non-toxic protein that binds to a glycosylated lipid, termed globotriaosylceramide (Gb3), which is preferentially expressed by dendritic cells. We review the use of STxB for the cross-presentation of tumor or viral antigens in a MHC class I-restricted manner to induce humoral immunity against these antigens in addition to polyfunctional and persistent CD4+ and CD8+ T lymphocytes capable of protecting against viral infection or tumor growth. Other literature will be summarized that documents a powerful induction of mucosal IgA and resident memory CD8+ T cells against mucosal tumors specifically when STxB-antigen conjugates are administered via the nasal route. It will also be pointed out how STxB-based vaccines have been shown in preclinical cancer models to synergize with other therapeutic modalities (immune checkpoint inhibitors, anti-angiogenic therapy, radiotherapy). Finally, we will discuss how molecular aspects such as low immunogenicity, cross-species conservation of Gb3 expression, and lack of toxicity contribute to the competitive positioning of STxB among the different DC targeting approaches. STxB thereby appears as an original and innovative tool for the development of mucosal vaccines in infectious diseases and cancer.
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2
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Overgaard E, Morris B, Mohammad Mousa O, Price E, Rodriguez A, Cufurovic L, Beard RS, Tinker JK. Cellular Activity of Salmonella Typhimurium ArtAB Toxin and Its Receptor-Binding Subunit. Toxins (Basel) 2021; 13:toxins13090599. [PMID: 34564603 PMCID: PMC8472264 DOI: 10.3390/toxins13090599] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 08/07/2021] [Accepted: 08/20/2021] [Indexed: 12/22/2022] Open
Abstract
Salmonellosis is among the most reported foodborne illnesses in the United States. The Salmonellaenterica Typhimurium DT104 phage type, which is associated with multidrug-resistant disease in humans and animals, possesses an ADP-ribosylating toxin called ArtAB. Full-length artAB has been found on a number of broad-host-range non-typhoidal Salmonella species and serovars. ArtAB is also homologous to many AB5 toxins from diverse Gram-negative pathogens, including cholera toxin (CT) and pertussis toxin (PT), and may be involved in Salmonella pathogenesis, however, in vitro cellular toxicity of ArtAB has not been characterized. artAB was cloned into E. coli and initially isolated using a histidine tag (ArtABHIS) and nickel chromatography. ArtABHIS was found to bind to African green monkey kidney epithelial (Vero) cells using confocal microscopy and to interact with glycans present on fetuin and monosialotetrahexosylganglioside (GM1) using ELISA. Untagged, or native, holotoxin (ArtAB), and the pentameric receptor-binding subunit (ArtB) were purified from E. coli using fetuin and d-galactose affinity chromatography. ArtAB and ArtB metabolic and cytotoxic activities were determined using Vero and Chinese hamster ovary (CHO) epithelial cells. Vero cells were more sensitive to ArtAB, however, incubation with both cell types revealed only partial cytotoxicity over 72 h, similar to that induced by CT. ArtAB induced a distinctive clustering phenotype on CHO cells over 72 h, similar to PT, and an elongated phenotype on Vero cells, similar to CT. The ArtB binding subunit alone also had a cytotoxic effect on CHO cells and induced morphological rounding. Results indicate that this toxin induces distinctive cellular outcomes. Continued biological characterization of ArtAB will advance efforts to prevent disease caused by non-typhoidal Salmonella.
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Affiliation(s)
- Elise Overgaard
- Biomolecular Sciences Graduate Program, Boise State University, Boise, ID 83725, USA;
| | - Brad Morris
- Department of Biology, Boise State University, Boise, ID 83725, USA; (B.M.); (O.M.M.); (A.R.); (L.C.)
| | - Omid Mohammad Mousa
- Department of Biology, Boise State University, Boise, ID 83725, USA; (B.M.); (O.M.M.); (A.R.); (L.C.)
| | - Emily Price
- Idaho Veterans Research and Education Foundation, Infectious Diseases Section, Boise, ID 83702, USA;
| | - Adriana Rodriguez
- Department of Biology, Boise State University, Boise, ID 83725, USA; (B.M.); (O.M.M.); (A.R.); (L.C.)
| | - Leyla Cufurovic
- Department of Biology, Boise State University, Boise, ID 83725, USA; (B.M.); (O.M.M.); (A.R.); (L.C.)
| | - Richard S. Beard
- Biomolecular Research Center, Boise State University, Boise, ID 83725, USA;
| | - Juliette K. Tinker
- Biomolecular Sciences Graduate Program, Boise State University, Boise, ID 83725, USA;
- Department of Biology, Boise State University, Boise, ID 83725, USA; (B.M.); (O.M.M.); (A.R.); (L.C.)
- Correspondence: ; Tel.: +1-208-426-5472
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Da Silva DM, Skeate JG, Chavez-Juan E, Lühen KP, Wu JM, Wu CM, Kast WM, Hwang K. Therapeutic efficacy of a human papillomavirus type 16 E7 bacterial exotoxin fusion protein adjuvanted with CpG or GPI-0100 in a preclinical mouse model for HPV-associated disease. Vaccine 2019; 37:2915-2924. [PMID: 31010714 DOI: 10.1016/j.vaccine.2019.04.043] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 04/10/2019] [Accepted: 04/15/2019] [Indexed: 12/18/2022]
Abstract
Persistent human papillomavirus (HPV) infection is causally linked to the development of several human cancers, including cervical, vulvar, vaginal, anal, penile, and oropharyngeal cancers. To address the need for a therapeutic vaccine against HPV-associated diseases, here we test and compare the immunogenicity and therapeutic efficacy of a bacterial exotoxin fusion protein covalently linked to the HPV16 E7 oncoprotein adjuvanted with CpG or GPI-0100 in the C3.43 preclinical HPV16-transformed tumor model. We show that TVGV-1 protein vaccine adjuvanted with either CpG or GPI-0100 adjuvant induces a high frequency of E7-specific CD8+ T cells, and both adjuvants are able to assist the immune response in inducing polyfunctional cytokine-secreting lytic T cells that show therapeutic efficacy against well-established C3.43 tumors. CpG-adjuvanted TVGV-1 resulted in higher frequencies of IFNγ secreting and degranulating E7-specific T cells compared to GPI-0100-adjuvanted TVGV-1, resulting in marginally increased in vivo efficacy. Despite minor differences in immune response outcomes, we consider both CpG ODN and GPI-0100 to be promising vaccine adjuvants to increase the immunogenicity and therapeutic efficacy of the TVGV-1 protein for HPV16-driven cancers.
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Affiliation(s)
- Diane M Da Silva
- Department of Obstetrics & Gynecology, University of Southern California, Los Angeles, CA 90033, USA; Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90033, USA.
| | - Joseph G Skeate
- Department of Molecular Microbiology & Immunology, University of Southern California, Los Angeles, CA 90033, USA
| | - Elena Chavez-Juan
- Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90033, USA
| | - Kim P Lühen
- Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90033, USA
| | - Jiun-Ming Wu
- TheVax Genetics Vaccine Co., Ltd, Zhubei City, Hsinchu County 302, Taiwan, ROC
| | - Chia-Mao Wu
- TheVax Genetics Vaccine Co., Ltd, Zhubei City, Hsinchu County 302, Taiwan, ROC
| | - W Martin Kast
- Department of Obstetrics & Gynecology, University of Southern California, Los Angeles, CA 90033, USA; Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90033, USA; Department of Molecular Microbiology & Immunology, University of Southern California, Los Angeles, CA 90033, USA
| | - KinKai Hwang
- TheVax Genetics Vaccine Co., Ltd, Irvine, CA 92618, USA
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Sustained Specific and Cross-Reactive T Cell Responses to Zika and Dengue Virus NS3 in West Africa. J Virol 2018; 92:JVI.01992-17. [PMID: 29321308 DOI: 10.1128/jvi.01992-17] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 12/21/2017] [Indexed: 01/05/2023] Open
Abstract
Recent studies on the role of T cells in Zika virus (ZIKV) infection have shown that T cell responses to Asian ZIKV infection are important for protection, and that previous dengue virus (DENV) exposure amplifies the protective T cell response to Asian ZIKV. Human T cell responses to African ZIKV infection, however, remain unexplored. Here, we utilized the modified anthrax toxin delivery system to develop a flavivirus enzyme-linked immunosorbent spot (ELISPOT) assay. Using human ZIKV and DENV samples from Senegal, West Africa, our results demonstrate specific and cross-reactive T cell responses to nonstructural protein 3 (NS3). Specifically, we found that T cell responses to NS3 protease are ZIKV and DENV specific, but responses to NS3 helicase are cross-reactive. Sequential sample analyses revealed immune responses sustained many years after infection. These results have important implications for African ZIKV/DENV vaccine development, as well as for potential flavivirus diagnostics based on T cell responses.IMPORTANCE The recent Zika virus (ZIKV) epidemic in Latin America and the associated congenital microcephaly and Guillain-Barré syndrome have raised questions as to why we have not recognized these distinct clinical diseases in Africa. The human immunologic response to ZIKV and related flaviviruses in Africa represents a research gap that may shed light on the mechanisms contributing to protection. The goal of our study was to develop an inexpensive assay to detect and characterize the T cell response to African ZIKV and DENV. Our data show long-term specific and cross-reactive human immune responses against African ZIKV and DENV, suggesting the usefulness of a diagnostic based on the T cell response. Additionally, we show that prior flavivirus exposure influences the magnitude of the T cell response. The identification of immune responses to African ZIKV and DENV is of relevance to vaccine development.
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Fernando LP, Lewis JS, Evans BC, Duvall CL, Keselowsky BG. Formulation and characterization of poly(propylacrylic acid)/poly(lactic-co-glycolic acid) blend microparticles for pH-dependent membrane disruption and cytosolic delivery. J Biomed Mater Res A 2017; 106:1022-1033. [PMID: 29164777 DOI: 10.1002/jbm.a.36298] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 09/22/2017] [Accepted: 10/17/2017] [Indexed: 01/15/2023]
Abstract
Poly(lactic-co-glycolic acid) (PLGA) is widely used as a vehicle for delivery of pharmaceutically relevant payloads. PLGA is readily fabricated as a nano- or microparticle (MP) matrix to load both hydrophobic and hydrophilic small molecular drugs as well as biomacromolecules such as nucleic acids and proteins. However, targeting such payloads to the cell cytosol is often limited by MP entrapment and degradation within acidic endolysosomes. Poly(propylacrylic acid) (PPAA) is a polyelectrolyte polymer with the membrane disruptive capability triggered at low pH. PPAA has been previously formulated in various carrier configurations to enable cytosolic payload delivery, but requires sophisticated carrier design. Taking advantage of PPAA functionality, we have incorporated PPAA into PLGA MPs as a simple polymer mixture to enhance cytosolic delivery of PLGA-encapsulated payloads. Rhodamine loaded PLGA and PPAA/PLGA blend MPs were prepared by a modified nanoprecipitation method. Incorporation of PPAA into PLGA MPs had little to no effect on the size, shape, or loading efficiency, and evidenced no toxicity in Chinese hamster ovary epithelial cells. Notably, incorporation of PPAA into PLGA MPs enabled pH-dependent membrane disruption in a hemolysis assay, and a three-fold increased endosomal escape and cytosolic delivery in dendritic cells after 2 h of MP uptake. These results demonstrate that a simple PLGA/PPAA polymer blend is readily fabricated into composite MPs, enabling cytosolic delivery of an encapsulated payload. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1022-1033, 2018.
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Affiliation(s)
- Lawrence P Fernando
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida
| | - Jamal S Lewis
- Department of Biomedical Engineering, University of California, Davis, Davis, California
| | - Brian C Evans
- Division of Vascular Surgery, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Craig L Duvall
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee
| | - Benjamin G Keselowsky
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida
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6
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Martínez-Hernández SL, Cervantes-García D, Muñoz-Ortega M, Aldaba-Muruato LR, Loera-Muro VM, Ascacio-Martínez JA, de Jesús Loera-Arias M, de Oca-Luna RM, Ventura-Juárez J. An anti-amoebic vaccine: generation of the recombinant antigen LC3 from Entamoeba histolytica linked to mutated exotoxin A (PEΔIII) via the Pichia pastoris system. Biotechnol Lett 2017; 39:1149-1157. [PMID: 28470625 DOI: 10.1007/s10529-017-2341-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 04/27/2017] [Indexed: 12/26/2022]
Abstract
OBJECTIVE To generate an immunogenic chimeric protein containing the Entamoeba histolytica LC3 fragment fused to the retrograde delivery domains of exotoxin A of Pseudomonas aeruginosa and KDEL3 for use as an effective vaccine. RESULTS A codon-optimized synthetic gene encoding the PEΔIII-LC3-KDEL3 fusion construct was designed for expression in Pichia pastoris. This transgene was subcloned into the plasmid pPIC9 for methanol-inducible expression. After transformation and selection of positive-transformed clones by PCR, the expression of the recombinant protein PEΔIII-LC3-KDEL3 was elicited. SDS-PAGE, protein glycosylation staining and western blot assays demonstrated a 67 kDa protein in the medium culture supernatant. The recombinant protein was detected with a polyclonal anti-6X His tag antibody and a polyclonal E. histolytica-specific antibody. A specific antibody response was induced in hamsters after immunization with this protein. CONCLUSIONS We report for the first time the design and expression of the recombinant E. histolytica LC3 protein fused to PEΔIII and KDEL3, with potential application as an immunogen.
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Affiliation(s)
- Sandra Luz Martínez-Hernández
- Departamento de Morfología, Centro de Ciencias Básicas, Universidad Autónoma de Aguascalientes, Av. Universidad # 940, Ciudad Universitaria, C. P. 20131, Aguascalientes, AGS, Mexico
| | - Daniel Cervantes-García
- CONACYT-Departamento de Microbiología, Centro de Ciencias Básicas, Universidad Autónoma de Aguascalientes, Aguascalientes, AGS, Mexico
| | - Martín Muñoz-Ortega
- Departamento de Química, Centro de Ciencias Básicas, Universidad Autónoma de Aguascalientes, Aguascalientes, AGS, Mexico
| | - Liseth R Aldaba-Muruato
- Departamento de Morfología, Centro de Ciencias Básicas, Universidad Autónoma de Aguascalientes, Av. Universidad # 940, Ciudad Universitaria, C. P. 20131, Aguascalientes, AGS, Mexico
| | - Victor M Loera-Muro
- Departamento de Fisiología y Farmacología, Centro de Ciencias Básicas, Universidad Autónoma de Aguascalientes, Aguascalientes, AGS, Mexico
| | - Jorge A Ascacio-Martínez
- Departamento de Bioquímica y Medicina Molecular, Centro de Investigación y Desarrollo en Ciencias de la Salud y, Universidad Autónoma de Nuevo León, Monterrey, NL, Mexico
| | - María de Jesús Loera-Arias
- Departamento de Histología, Facultad de Medicina, Universidad Autónoma de Nuevo León, Monterrey, NL, Mexico
| | - Roberto Montes de Oca-Luna
- Departamento de Histología, Facultad de Medicina, Universidad Autónoma de Nuevo León, Monterrey, NL, Mexico
| | - Javier Ventura-Juárez
- Departamento de Morfología, Centro de Ciencias Básicas, Universidad Autónoma de Aguascalientes, Av. Universidad # 940, Ciudad Universitaria, C. P. 20131, Aguascalientes, AGS, Mexico.
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Tang DCC. A trail blazed through DNA vaccine, noninvasive vaccine, and innate-adaptive immunity duo. Hum Vaccin Immunother 2015; 10:2143-6. [PMID: 25424917 PMCID: PMC4896786 DOI: 10.4161/hv.29044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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8
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Gurnev PA, Nestorovich EM. Channel-forming bacterial toxins in biosensing and macromolecule delivery. Toxins (Basel) 2014; 6:2483-540. [PMID: 25153255 PMCID: PMC4147595 DOI: 10.3390/toxins6082483] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 08/08/2014] [Accepted: 08/08/2014] [Indexed: 12/19/2022] Open
Abstract
To intoxicate cells, pore-forming bacterial toxins are evolved to allow for the transmembrane traffic of different substrates, ranging from small inorganic ions to cell-specific polypeptides. Recent developments in single-channel electrical recordings, X-ray crystallography, protein engineering, and computational methods have generated a large body of knowledge about the basic principles of channel-mediated molecular transport. These discoveries provide a robust framework for expansion of the described principles and methods toward use of biological nanopores in the growing field of nanobiotechnology. This article, written for a special volume on "Intracellular Traffic and Transport of Bacterial Protein Toxins", reviews the current state of applications of pore-forming bacterial toxins in small- and macromolecule-sensing, targeted cancer therapy, and drug delivery. We discuss the electrophysiological studies that explore molecular details of channel-facilitated protein and polymer transport across cellular membranes using both natural and foreign substrates. The review focuses on the structurally and functionally different bacterial toxins: gramicidin A of Bacillus brevis, α-hemolysin of Staphylococcus aureus, and binary toxin of Bacillus anthracis, which have found their "second life" in a variety of developing medical and technological applications.
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Affiliation(s)
- Philip A Gurnev
- Physics Department, University of Massachusetts, Amherst, MA 01003, USA.
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Chiang HL, Lin CY, Jan FD, Lin YS, Hsu CT, Whang-Peng J, Liu LF, Nieh S, Lin CC, Hwang J. A novel synthetic bipartite carrier protein for developing glycotope-based vaccines. Vaccine 2012; 30:7573-81. [PMID: 23099332 PMCID: PMC3513549 DOI: 10.1016/j.vaccine.2012.10.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 10/06/2012] [Accepted: 10/11/2012] [Indexed: 11/18/2022]
Abstract
Development of successful vaccines against glycotopes remains a major challenge. In the current studies, we have successfully developed a novel carrier protein for glycotopes based on the concept of antigen clustering and specific stimulation of T helper cells to mount strong antibody response to glycotopes. The bipartite carrier protein consists of a tandem repeat of a cysteine-rich peptide for docking of clustered glycotopes to effectively activate B cells and an Fc domain for antigen delivery to antigen presenting cells (APCs). To demonstrate its utility, we conjugated the tumor-specific monosaccharide antigen Tn to this novel carrier protein and successfully developed a Tn vaccine against cancer in animal models. The Tn vaccine effectively elicited high-titer IgG1 antibodies against Tn in immunized mice, and effectively suppressed the development of prostate cancer in Transgenic Adenocarcinoma of the Mouse Prostate (TRAMP) mice. Our results suggest that this novel bipartite carrier protein could be effectively used for developing anti-glycotope vaccines such as the anticancer Tn vaccine.
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Affiliation(s)
- Hsiao-Ling Chiang
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
- Department of Biochemistry, School of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Chi-Yu Lin
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
- Department of Biochemistry, School of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Fan-Dan Jan
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
| | - Yaoh-Shiang Lin
- Department of Otolaryngology-Head and Neck Surgery, National Defense Medical Centre & Tri-Service General Hospital, Taipei, Taiwan
| | - Chia-Tse Hsu
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | | | - Leroy F. Liu
- Department of Pharmacology, The University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
| | - Shin Nieh
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
- Department of Pathology, Tri-Service General Hospital, Taipei, Taiwan
| | - Chun-Cheng Lin
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
| | - Jaulang Hwang
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
- Department of Biochemistry, School of Medicine, Taipei Medical University, Taipei, Taiwan
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Affiliation(s)
| | - Sergey M. Bezrukov
- Program in Physical Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, U.S.A
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Crownover EF, Convertine AJ, Stayton PS. pH-responsive polymer–antigen vaccine bioconjugates. Polym Chem 2011. [DOI: 10.1039/c1py00060h] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Foster S, Duvall CL, Crownover EF, Hoffman AS, Stayton PS. Intracellular delivery of a protein antigen with an endosomal-releasing polymer enhances CD8 T-cell production and prophylactic vaccine efficacy. Bioconjug Chem 2010; 21:2205-12. [PMID: 21043513 DOI: 10.1021/bc100204m] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Protein-based vaccines have significant potential as infectious disease and anticancer therapeutics, but clinical impact has been limited in some applications by their inability to generate a coordinated cellular immune response. Here, a pH-responsive carrier incorporating poly(propylacrylic acid) (PPAA) was evaluated to test whether improved cytosolic delivery of a protein antigen could enhance CD8+ cytotoxic lymphocyte generation and prophylactic tumor vaccine responses. PPAA was directly conjugated to the model ovalbumin antigen via reducible disulfide linkages and was also tested in a particulate formulation after condensation with cationic poly(dimethylaminoethyl methacrylate) (PDMAEMA). Intracellular trafficking studies revealed that both PPAA-containing formulations were stably internalized and evaded exocytotic pathways, leading to increased intracellular accumulation and potential access to the cytosolic MHC-1 antigen presentation pathway. In an EG.7-OVA mouse tumor protection model, both PPAA-containing carriers robustly inhibited tumor growth and led to an approximately 3.5-fold increase in the longevity of tumor-free survival relative to controls. Mechanistically, this response was attributed to the 8-fold increase in production of ovalbumin-specific CD8+ T-lymphocytes and an 11-fold increase in production of antiovalbumin IgG. Significantly, this is one of the first demonstrated examples of in vivo immunotherapeutic efficacy using soluble protein-polymer conjugates. These results suggest that carriers enhancing cytosolic delivery of protein antigens could lead to more robust CD8+ T-cell response and demonstrate the potential of pH-responsive PPAA-based carriers for therapeutic vaccine applications.
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Affiliation(s)
- Suzanne Foster
- Department of Bioengineering and Center for Intracellular Delivery of Biologics, University of Washington, Seattle Washington 98195, USA
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Majd S, Yusko EC, Billeh YN, Macrae MX, Yang J, Mayer M. Applications of biological pores in nanomedicine, sensing, and nanoelectronics. Curr Opin Biotechnol 2010; 21:439-76. [PMID: 20561776 PMCID: PMC3121537 DOI: 10.1016/j.copbio.2010.05.002] [Citation(s) in RCA: 237] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Revised: 05/03/2010] [Accepted: 05/06/2010] [Indexed: 12/29/2022]
Abstract
Biological protein pores and pore-forming peptides can generate a pathway for the flux of ions and other charged or polar molecules across cellular membranes. In nature, these nanopores have diverse and essential functions that range from maintaining cell homeostasis and participating in cell signaling to activating or killing cells. The combination of the nanoscale dimensions and sophisticated - often regulated - functionality of these biological pores make them particularly attractive for the growing field of nanobiotechnology. Applications range from single-molecule sensing to drug delivery and targeted killing of malignant cells. Potential future applications may include the use of nanopores for single strand DNA sequencing and for generating bio-inspired, and possibly, biocompatible visual detection systems and batteries. This article reviews the current state of applications of pore-forming peptides and proteins in nanomedicine, sensing, and nanoelectronics.
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Affiliation(s)
- Sheereen Majd
- Department of Biomedical Engineering, University of Michigan, 1101 Beal Avenue, Ann Arbor, Michigan 48109-2110, USA
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Flanary S, Hoffman AS, Stayton PS. Antigen delivery with poly(propylacrylic acid) conjugation enhances MHC-1 presentation and T-cell activation. Bioconjug Chem 2009; 20:241-8. [PMID: 19125614 DOI: 10.1021/bc800317a] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
While many infectious diseases are controlled by vaccine strategies, important limitations continue to motivate the development of better antigen delivery systems. This study focuses on the use of a pH-sensitive polymeric carrier based on poly(propylacrylic acid) (PPAA) to address the need for more potent CD8 cytotoxic T-cell (CTL) responses. An MHC-1/CD8 CTL cell model system with ovalbumin as the protein antigen was used to test whether PPAA could enhance the delivery of ovalbumin into the MHC-1 display pathway. Ovalbumin was conjugated to poly(propylacrylic acid-co-pyridyldisulfide acrylate) (PPAA-PDSA) by disulfide exchange to make reversible conjugates that could be reduced by the glutathione redox system in the cytosol of antigen presenting cells. The PPAA-PDSA ovalbumin conjugates displayed the pH-sensitive membrane disruptive properties of the parent polymer as determined by their hemolysis activities (sharply active at the endosomal pH values of 6-6.5). The polymer-ovalbumin conjugates exhibited strong 22-fold increases in the MHC-1 presentation and ovalbumin-specific CTL activation compared to free ovalbumin. No CTL activation was observed with control conjugates of ovalbumin and poly(methylacrylic acid) (PMAA) that do not display membrane disruptive activies, suggesting that it is the membrane destabilizing properties of the polymer that result in increased MHC-1 display and CTL activation. Further mechanistic studies quantitated the time course of stable intracellular localization of radiolabeled conjugates. 52% of initially internalized PPAA-conjugated ovalbumin remained in the cells after 4 h, compared to less than 10% of ovalbumin or PMAA-ovalbumin. These results showing enhanced cytosolic delivery and MHC-1 presentation for the PPAA-antigen conjugates suggest that they warrant future characterization as a CD8-enhancing vaccine delivery system.
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Affiliation(s)
- Suzanne Flanary
- Department of Bioengineering, University of Washington, Seattle, Washington 98195, USA
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15
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Engelhorn ME, Guevara-Patiño JA, Merghoub T, Liu C, Ferrone CR, Rizzuto GA, Cymerman DH, Posnett DN, Houghton AN, Wolchok JD. Mechanisms of immunization against cancer using chimeric antigens. Mol Ther 2008; 16:773-81. [PMID: 18301399 PMCID: PMC4399381 DOI: 10.1038/mt.2008.8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Successful approaches to tumor immunotherapy must overcome the physiological state of tolerance of the immune system to self-tumor antigens. Immunization with appropriate variants of syngeneic antigens can achieve this. However, improvements in vaccine design are needed for efficient cancer immunotherapy. Here we explore nine different chimeric vaccine designs, in which the antigen of interest is expressed as an in-frame fusion with polypeptides that impact antigen processing or presentation. In DNA immunization experiments in mice, three of nine fusions elevated relevant CD8(+) T-cell responses and tumor protection relative to an unfused melanoma antigen. These fusions were: Escherichia coli outer membrane protein A (OmpA), Pseudomonas aeruginosa exotoxin A, and VP22 protein of herpes simplex virus-1. The gains of immunogenicity conferred by the latter two are independent of epitope presentation by major histocompatibility complex class II (MHC II). This finding has positive implications for immunotherapy in individuals with CD4(+) T-cell deficiencies. We present evidence that antigen instability is not a sine qua non condition for immunogenicity. Experiments using two additional melanoma antigens identified different optimal fusion partners, thereby indicating that the benefits of fusion vectors remain antigen specific. Therefore large fusion vector panels such as those presented here can provide information to promote the successful advancement of gene-based vaccines.
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Affiliation(s)
- Manuel E Engelhorn
- The Swim Across America Laboratory, Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA
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16
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Zhang Y, Qiu J, Zhou Y, Farhangfar F, Hester J, Lin AY, Decker WK. Plasmid-based vaccination with candidate anthrax vaccine antigens induces durable type 1 and type 2 T-helper immune responses. Vaccine 2008; 26:614-22. [DOI: 10.1016/j.vaccine.2007.11.072] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2007] [Revised: 11/21/2007] [Accepted: 11/27/2007] [Indexed: 10/22/2022]
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17
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Bendz H, Ruhland SC, Pandya MJ, Hainzl O, Riegelsberger S, Braüchle C, Mayer MP, Buchner J, Issels RD, Noessner E. Human heat shock protein 70 enhances tumor antigen presentation through complex formation and intracellular antigen delivery without innate immune signaling. J Biol Chem 2007; 282:31688-702. [PMID: 17684010 DOI: 10.1074/jbc.m704129200] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Heat shock proteins (HSPs) have shown promise for the optimization of protein-based vaccines because they can transfer exogenous antigens to dendritic cells and at the same time induce their maturation. Great care must be exercised in interpretating HSP-driven studies, as by-products linked to the recombinant generation of these proteins have been shown to mediate immunological effects. We generated highly purified human recombinant Hsp70 and demonstrated that it strongly enhances the cross-presentation of exogenous antigens resulting in better antigen-specific T cell stimulation. Augmentation of T cell stimulation was a direct function of the degree of complex formation between Hsp70 and peptides and correlated with improved antigen delivery to endosomal compartments. The Hsp70 activity was independent of TAP proteins and was not inhibited by exotoxin A or endosomal acidification. Consequently, Hsp70 enhanced cross-presentation of various antigenic sequences, even when they required different post-uptake processing and trafficking, as exemplified by the tumor antigens tyrosinase and Melan-A/MART-1. Furthermore, Hsp70 enhanced cross-presentation by different antigen-presenting cells (APCs), including dendritic cells and B cells. Importantly, enhanced cross-presentation and antigen-specific T cell activation were observed in the absence of innate signals transmitted by Hsp70. As Hsp70 supports the cross-presentation of different antigens and APCs and is inert to APC function, it may show efficacy in various settings of immune modulation, including induction of antigen-specific immunity or tolerance.
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Affiliation(s)
- Henriette Bendz
- Institute of Molecular Immunology, GSF-National Research Center for Environment and Health Klinikum Grosshadern, Ludwig-Maximilians-University, Marchioninistrasse 25, 81377 Munich, Germany.
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18
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Chandra S, Kaur M, Midha S, Gorantala J, Bhatnagar R. Induction of cytotoxic T lymphocyte response against Mycobacterial antigen using domain I of anthrax edema factor as antigen delivery system. Biochem Biophys Res Commun 2007; 357:50-5. [PMID: 17416345 DOI: 10.1016/j.bbrc.2007.03.166] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2007] [Accepted: 03/27/2007] [Indexed: 11/25/2022]
Abstract
We have investigated the efficiency of N-terminal 1-260 residues of Edema factor (EFn) as a delivery system for ESAT-6, an antigenic protein of Mycobacterium tuberculosis H(37)R(v), into the cytosol of mammalian cells. The EFn.ESAT-6 recombinant protein was obtained by genetic fusion of EFn and ESAT-6 DNA. Our data shows that in the presence of PA, EFn.ESAT-6 fusion protein is internalized into the cytosol of antigen presenting cells, and the splenocytes produced both Th1 and Th2 cytokines in vitro. Further, EFn.ESAT-6 elicited effective cytotoxic T lymphocyte (CTL) response in an in vitro CTL assay. This study for the first time demonstrates that EFn can be used as a vehicle to deliver heterologous proteins of therapeutic importance.
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Affiliation(s)
- Subhash Chandra
- School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India
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19
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Challa S, Barrette R, Rood D, Zinckgraf J, French R, Silbart L. Non-toxic Pseudomonas aeruginosa exotoxin A expressing the FMDV VP1 G-H loop for mucosal vaccination of swine against foot and mouth disease virus. Vaccine 2007; 25:3328-37. [PMID: 17276557 DOI: 10.1016/j.vaccine.2007.01.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2006] [Revised: 01/01/2007] [Accepted: 01/03/2007] [Indexed: 11/20/2022]
Abstract
Synthetic peptides derived from the G-H loop of the foot and mouth disease virus (FMDV) capsid protein VP1 are relatively poor at recapitulating the native conformation present in the virus, and thus are often poor immunogens. We hypothesized that a candidate mucosal vaccine against FMDV could be developed using the non-toxic Pseudomonas aeruginosa exotoxin A (ntPE) to deliver the G-H loop in its native conformation. An added benefit of this approach is the potential for ntPE to serve as an effective carrier/adjuvant molecule for delivery of the fusion protein across the epithelial barrier by virtue of its capacity to bind to CD91. A chimeric protein (ntPE-GH) was generated by inserting the coding sequence of the G-H loop into an expression plasmid encoding ntPE, in place of the native Ib loop. Recombinant ntPE-GH and wild-type ntPE were each expressed in Escherichia coli, purified over a nickel resin, then administered intranasally to the pigs, with or without the mucosal adjuvant cholera toxin (CT). Both the ntPE and ntPE-GH induced mucosal and systemic immune responses against ntPE; moreover, ntPE-GH administered without CT induced anti-GH loop serum IgG antibodies. In conclusion, these data demonstrate that ntPE can be used as a mucosal carrier/adjuvant to induce an immune response against the VP1 G-H loop of FMDV.
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Affiliation(s)
- Sreerupa Challa
- Department of Animal Science, University of Connecticut, Storrs, CT 06269, USA
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20
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Luria-Perez R, Cedillo-Barron L, Santos-Argumedo L, Ortiz-Navarrete VF, Ocaña-Mondragon A, Gonzalez-Bonilla CR. A fusogenic peptide expressed on the surface of Salmonella enterica elicits CTL responses to a dengue virus epitope. Vaccine 2007; 25:5071-85. [PMID: 17543427 DOI: 10.1016/j.vaccine.2007.03.047] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2006] [Revised: 03/23/2007] [Accepted: 03/30/2007] [Indexed: 10/23/2022]
Abstract
Attenuated Salmonella strains are used widely as live carriers of antigens because they elicit both mucosal and systemic immunity against passenger antigens. However, they generally evoke poor cytotoxic T cell (CTL) responses because Salmonella resides within vacuolar compartments and the passenger antigens must travel to the cytosol and be processed through the MHC class I-dependent pathway to simulate CTLs. To address this problem, we designed a fusion protein to destabilize the phagosome membrane and allow a dengue epitope to reach the cytosol. The fusion protein was displayed on the bacterial surface of Salmonella enterica serovar Typhimurium SL3261 through the beta domain of the autotransporter MisL. The passenger alpha domain contained, from the N-terminus, a fusogenic sequence, the NS3 protein 298-306-amino acid CTL epitope from the dengue virus type 2, a molecular tag, and a recognition site for the protease OmpT to release it to the milieu. Display of the fusion protein on the bacterial surface was demonstrated by IFA and flow cytometry using antibodies against the molecular tag. Cleavage of the fusogenic protein-dengue peptide was demonstrated by flow cytometry using OmpT+ Escherichia coli strains. The recombinant Salmonella strains displaying the fusogenic-dengue peptide were able to lyse erythrocytes, induced specific proliferative responses, and elicited CTL responses. These results suggest that the recombinant fusion proteins containing fusogenic sequences provide a promising system to induce CTLs by live vector vaccines.
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Affiliation(s)
- R Luria-Perez
- Medical Research Unit on Immunology and Infectious Diseases, Infectology Hospital, National Medical Center La Raza, IMSS, México City, Mexico
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21
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Scuderi F, Mannella F, Marino M, Provenzano C, Bartoccioni E. IL-6-deficient mice show impaired inflammatory response in a model of myosin-induced experimental myositis. J Neuroimmunol 2006; 176:9-15. [PMID: 16725212 DOI: 10.1016/j.jneuroim.2006.03.026] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2005] [Revised: 03/29/2006] [Accepted: 03/29/2006] [Indexed: 11/17/2022]
Abstract
Inflammatory/immune reactions against muscle cells are responsible for the damage in idiopathic inflammatory myopathies. We investigated the role of IL-6, a cytokine known to contribute to local leukocyte accumulation, in a model of myosin-induced experimental myositis. After injection of rabbit myosin in CFA/pertussis toxin, normal mice develop clinically evident muscle deficit and damage, as demonstrated by myofiber necrosis and leukocyte infiltration, while IL-6-deficient mice have no clinical or histological signs of muscle damage. This study evidences that selective deficiency of IL-6 directly or indirectly hinders the local inflammatory response and its harmful effects in this model of muscle damage.
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Affiliation(s)
- Flavia Scuderi
- Institute of General Pathology, Catholic University, Largo F. Vito 1, 00168 Rome, Italy
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22
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Krakauer T, Little SF, Stiles BG. Bacillus anthracis edema toxin inhibits Staphylococcus aureus enterotoxin B effects in vitro: a potential protein therapeutic? Infect Immun 2005; 73:7069-73. [PMID: 16177395 PMCID: PMC1230970 DOI: 10.1128/iai.73.10.7069-7073.2005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Various in vitro effects of staphylococcal enterotoxin B (SEB) on human peripheral blood mononuclear cells were mitigated by Bacillus anthracis edema toxin. In particular, levels of some SEB-induced cytokines (tumor necrosis factor alpha, gamma interferon) and chemokines (monocyte chemoattractant protein 1, macrophage inflammatory protein 1 alpha [MIP-1alpha], MIP-1beta) were significantly diminished or even nonexistent, depending upon the timing of edema toxin administration. Overall, these results suggest a novel use of B. anthracis edema toxin against a bacterial superantigen.
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Affiliation(s)
- Teresa Krakauer
- Integrated Toxicology, US Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland 21702-5011, USA
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23
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Liao CW, Chen CA, Lee CN, Su YN, Chang MC, Syu MH, Hsieh CY, Cheng WF. Fusion protein vaccine by domains of bacterial exotoxin linked with a tumor antigen generates potent immunologic responses and antitumor effects. Cancer Res 2005; 65:9089-98. [PMID: 16204084 DOI: 10.1158/0008-5472.can-05-0958] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Antigen-specific immunotherapy represents an attractive approach for cancer treatment because of the capacity to eradicate systemic tumors at multiple sites in the body while retaining the requisite specificity to discriminate between neoplastic and nonneoplastic cells. It has been shown that certain domains of bacterial exotoxins facilitate translocation from extracellular and vesicular compartments into the cytoplasm. This feature provides an opportunity to enhance class I and/or II presentation of exogenous antigen to T lymphocytes. We investigated previously whether the translocation domain (domain II) of Pseudomonas aeruginosa exotoxin A with a model tumor antigen, human papillomavirus type 16 E7, in the context of a DNA vaccine could enhance vaccine potency. We then attempted to determine whether this chimeric molecule could also generate strong antigen-specific immunologic responses and enhance the potency of cancer vaccine in the protein format. Our results show that vaccination with the PE(DeltaIII)-E7-KDEL3 fusion protein enhances MHC class I and II presentation of E7, leading to dramatic increases in the number of E7-specific CD8+ and CD4+ T-cell precursors and markedly raised titers of E7-specific antibodies. Furthermore, the PE(DeltaIII)-E7-KDEL3 protein generates potent antitumor effects against s.c. E7-expressing tumors and preestablished E7-expressing metastatic lung tumors. Further, mice immunized with PE(DeltaIII)-E7-KDEL3 protein vaccine also retained long-term immunologic responses and antitumor effects. Our results indicate that retrograde-fusion protein via the delivery domains of exotoxins with an antigen greatly enhances in vivo antigen-specific immunologic responses and represents a novel strategy to improve cancer vaccine potency.
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MESH Headings
- ADP Ribose Transferases/genetics
- ADP Ribose Transferases/immunology
- Animals
- Bacterial Toxins/genetics
- Bacterial Toxins/immunology
- CD8-Positive T-Lymphocytes/immunology
- Cancer Vaccines/genetics
- Cancer Vaccines/immunology
- Cancer Vaccines/pharmacology
- Epitopes, T-Lymphocyte/immunology
- Exotoxins/genetics
- Exotoxins/immunology
- Female
- Lung Neoplasms/immunology
- Lung Neoplasms/prevention & control
- Lung Neoplasms/secondary
- Mice
- Mice, Inbred C57BL
- Neoplasms, Experimental/immunology
- Neoplasms, Experimental/pathology
- Neoplasms, Experimental/prevention & control
- Oligopeptides/genetics
- Oligopeptides/immunology
- Oncogene Proteins, Viral/genetics
- Oncogene Proteins, Viral/immunology
- Papillomavirus E7 Proteins
- Protein Sorting Signals/genetics
- Protein Structure, Tertiary
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/immunology
- Recombinant Fusion Proteins/pharmacology
- Vaccines, Synthetic/genetics
- Vaccines, Synthetic/immunology
- Vaccines, Synthetic/pharmacology
- Virulence Factors/genetics
- Virulence Factors/immunology
- Pseudomonas aeruginosa Exotoxin A
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24
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Palliser D, Guillen E, Ju M, Eisen HN. Multiple Intracellular Routes in the Cross-Presentation of a Soluble Protein by Murine Dendritic Cells. THE JOURNAL OF IMMUNOLOGY 2005; 174:1879-87. [PMID: 15699114 DOI: 10.4049/jimmunol.174.4.1879] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Soluble heat shock fusion proteins (Hsfp) stimulate mice to produce CD8+ CTL, indicating that these proteins are cross-presented by dendritic cells (DC) to naive CD8 T cells. We report that cross-presentation of these proteins depends upon their binding to DC receptors, likely belonging to the scavenger receptor superfamily. Hsfp entered DC by receptor-mediated endocytosis that was either inhibitable by cytochalasin D or not inhibitable, depending upon aggregation state and time. Most endocytosed Hsfp was transported to lysosomes, but not the small cross-presented fraction that exited early from the endocytic pathway and required access to proteasomes and TAP. Naive CD8 T cell (2C and OT-I) responses to DC incubated with Hsfp at 1 microM were matched by incubating DC with cognate octapeptides at 1-10 pM, indicating that display of very few class I MHC-peptide complexes per DC can be sufficient for cross-presentation. With an Hsfp (heat shock protein-OVA) having peptide sequences for both CD4+ (OT-II) and CD8+ (OT-I) cells, the CD4 cells responded far more vigorously than the CD8 cells and many more class II MHC-peptide than class I MHC-peptide complexes were displayed.
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Affiliation(s)
- Deborah Palliser
- Center for Cancer Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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25
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Bulmus V. Biomembrane-Active Molecular Switches as Tools for Intracellular Drug Delivery. Aust J Chem 2005. [DOI: 10.1071/ch05066] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Many therapeutic strategies, such as gene therapy and vaccine development require the delivery of polar macromolecules (e.g. DNA, RNA, and proteins) to intracellular sites at a therapeutic concentration. For such macromolecular therapeutics, cellular membranes constitute a major transport barrier that must be overcome before these drugs can exert their biological activity inside cells. A number of biological organisms, e.g. viruses and toxins, efficiently destabilize the cellular membranes upon a trigger, such as low pH, and facilitate the delivery of their biological cargo to the cytoplasm of host cell. pH-responsive synthetic peptides and polymers have been designed to mimic the function of membrane-destabilizing natural organisms and evaluated as a part of drug delivery systems. In this Review, pH-dependent membrane activity of natural and synthetic systems is reviewed, focussing on fundamental and practical aspects of pH-responsive, membrane-disruptive synthetic polymers in intracellular drug delivery.
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26
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Barth H, Aktories K, Popoff MR, Stiles BG. Binary bacterial toxins: biochemistry, biology, and applications of common Clostridium and Bacillus proteins. Microbiol Mol Biol Rev 2004; 68:373-402, table of contents. [PMID: 15353562 PMCID: PMC515256 DOI: 10.1128/mmbr.68.3.373-402.2004] [Citation(s) in RCA: 285] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Certain pathogenic species of Bacillus and Clostridium have developed unique methods for intoxicating cells that employ the classic enzymatic "A-B" paradigm for protein toxins. The binary toxins produced by B. anthracis, B. cereus, C. botulinum, C. difficile, C. perfringens, and C. spiroforme consist of components not physically associated in solution that are linked to various diseases in humans, animals, or insects. The "B" components are synthesized as precursors that are subsequently activated by serine-type proteases on the targeted cell surface and/or in solution. Following release of a 20-kDa N-terminal peptide, the activated "B" components form homoheptameric rings that subsequently dock with an "A" component(s) on the cell surface. By following an acidified endosomal route and translocation into the cytosol, "A" molecules disable a cell (and host organism) via disruption of the actin cytoskeleton, increasing intracellular levels of cyclic AMP, or inactivation of signaling pathways linked to mitogen-activated protein kinase kinases. Recently, B. anthracis has gleaned much notoriety as a biowarfare/bioterrorism agent, and of primary interest has been the edema and lethal toxins, their role in anthrax, as well as the development of efficacious vaccines and therapeutics targeting these virulence factors and ultimately B. anthracis. This review comprehensively surveys the literature and discusses the similarities, as well as distinct differences, between each Clostridium and Bacillus binary toxin in terms of their biochemistry, biology, genetics, structure, and applications in science and medicine. The information may foster future studies that aid novel vaccine and drug development, as well as a better understanding of a conserved intoxication process utilized by various gram-positive, spore-forming bacteria.
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Affiliation(s)
- Holger Barth
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Otto-Krayer-Haus, Albertstrasse 25, D-79104 Freiburg, Germany.
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27
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Schlecht G, Loucka J, Najar H, Sebo P, Leclerc C. Antigen Targeting to CD11b Allows Efficient Presentation of CD4+ and CD8+ T Cell Epitopes and In Vivo Th1-Polarized T Cell Priming. THE JOURNAL OF IMMUNOLOGY 2004; 173:6089-97. [PMID: 15528345 DOI: 10.4049/jimmunol.173.10.6089] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Bordetella pertussis adenylate cyclase (CyaA) is an invasive bacterial toxin that delivers its N-terminal catalytic domain into the cytosol of eukaryotic cells bearing the alpha(M)beta(2) integrin (CD11b/CD18), such as myeloid dendritic cells. This allows use of engineered CyaA for targeted delivery of CD8(+) T cell epitopes into the MHC class I pathway of APC and induction of robust and protective cytotoxic responses. In this study, we demonstrate that CyaA can efficiently codeliver both a CD8(+) T cell epitope (OVA(257-264)) and a CD4(+) T cell epitope (MalE(100-114)) into, respectively, the conventional cytosolic or endocytic routes of processing of murine bone marrow-derived dendritic cells. Upon CyaA delivery, a strong potentiation of the MalE(100-114) CD4(+) T cell epitope presentation is observed as compared with the MalE protein, which depends on CyaA interaction with its CD11b receptor and its subsequent clathrin-mediated endocytosis. In vivo, CyaA induces strong and specific Th1 CD4(+) and CD8(+) T cell responses against, respectively, the MalE(100-114) and OVA(257-264) epitopes. These results underscore the potency of CyaA for design of new vaccines.
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MESH Headings
- ATP-Binding Cassette Transporters/metabolism
- Actins/metabolism
- Adenylate Cyclase Toxin/administration & dosage
- Adenylate Cyclase Toxin/genetics
- Adenylate Cyclase Toxin/immunology
- Adenylate Cyclase Toxin/metabolism
- Amino Acid Sequence
- Animals
- Antigen Presentation/genetics
- Bone Marrow Cells/enzymology
- Bone Marrow Cells/immunology
- Bone Marrow Cells/metabolism
- CD11b Antigen/metabolism
- CD4-Positive T-Lymphocytes/enzymology
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- CD8-Positive T-Lymphocytes/enzymology
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- Clathrin-Coated Vesicles/physiology
- Cytotoxicity, Immunologic/genetics
- Dendritic Cells/enzymology
- Dendritic Cells/immunology
- Dendritic Cells/metabolism
- Drug Delivery Systems/methods
- Endosomes/enzymology
- Endosomes/immunology
- Endosomes/metabolism
- Epitopes, T-Lymphocyte/genetics
- Epitopes, T-Lymphocyte/immunology
- Epitopes, T-Lymphocyte/metabolism
- Escherichia coli Proteins/administration & dosage
- Escherichia coli Proteins/genetics
- Escherichia coli Proteins/immunology
- Female
- Genes, Reporter
- Histocompatibility Antigens Class I/metabolism
- Histocompatibility Antigens Class II/metabolism
- Hybridomas
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Molecular Sequence Data
- Ovalbumin/administration & dosage
- Ovalbumin/genetics
- Ovalbumin/immunology
- Peptide Fragments/administration & dosage
- Peptide Fragments/genetics
- Peptide Fragments/immunology
- Peptide Fragments/metabolism
- Peptide Hydrolases/physiology
- Periplasmic Binding Proteins/administration & dosage
- Periplasmic Binding Proteins/genetics
- Periplasmic Binding Proteins/immunology
- Proteasome Endopeptidase Complex/metabolism
- Th1 Cells/enzymology
- Th1 Cells/immunology
- Th1 Cells/metabolism
- Vaccines, Synthetic/administration & dosage
- Vaccines, Synthetic/immunology
- Vaccines, Synthetic/metabolism
- Vacuoles/metabolism
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Affiliation(s)
- Géraldine Schlecht
- Unité de Biologie des Régulations Immunitaires, Institut National de la Santé et de la Recherche Médicale E 352, Institut Pasteur, 25 rue du Docteur Roux, 75724 Paris cedex 15, Paris, France
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28
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Simsova M, Sebo P, Leclerc C. The adenylate cyclase toxin from Bordetella pertussis--a novel promising vehicle for antigen delivery to dendritic cells. Int J Med Microbiol 2004; 293:571-6. [PMID: 15149033 DOI: 10.1078/1438-4221-00291] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bordetella pertussis secretes an adenylate cyclase toxin (CyaA or ACT) that targets primarily cells expressing the alphaMbeta2 integrin (CD11b/CD18) receptor. This toxin can deliver its N-terminal catalytic AC domain (400 amino acid residues) into the cytosol directly across the cytoplasmic membrane. Various heterologous CD8+, as well as CD4+ T-cell epitopes have been engineered into genetically detoxified CyaA and the resulting toxoids were successfully used as vectors for delivery of inserted epitopes into antigen-presenting cells. Upon processing and presentation, these recombinant CyaAs trigger specific MHC class I and/or class II-restricted T-cell responses both in vitro and in vivo.
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Affiliation(s)
- Marcela Simsova
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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29
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Abstract
Anthrax toxin consists of three nontoxic proteins that associate in binary or ternary combinations to form toxic complexes at the surface of mammalian cells. One of these proteins, protective antigen (PA), transports the other two, edema factor (EF) and lethal factor (LF), to the cytosol. LF is a Zn2+-protease that cleaves certain MAP kinase kinases, leading to death of the host via a poorly defined sequence of events. EF, a calmodulin- and Ca2+-dependent adenylate cyclase, is responsible for the edema seen in the disease. Both enzymes are believed to benefit the bacteria by inhibiting cells of the host's innate immune system. Assembly of toxic complexes begins after PA binds to cellular receptors and is cleaved into two fragments by furin proteases. The smaller fragment dissociates, allowing the receptor-bound fragment, PA63 (63 kDa), to self-associate and form a ring-shaped, heptameric pore precursor (prepore). The prepore binds up to three molecules of EF and/or LF, and the resulting complexes are endocytosed and trafficked to an acidic compartment. There, the prepore converts to a transmembrane pore, mediating translocation of EF and LF to the cytosol. Recent studies have revealed (a) the identity of receptors; (b) crystallographic structures of the three toxin proteins and the heptameric PA63 prepore; and (c) information about toxin assembly, entry, and action within the cytosol. Knowledge of the structure and mode of action of the toxin has unveiled potential applications in medicine, including approaches to treating anthrax infections.
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Affiliation(s)
- R John Collier
- Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA.
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30
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Maisnier-Patin K, Malissard M, Jeannin P, Haeuw JF, Corbière JC, Hoeffel G, Gauchat JF, Nguyen T, Saez JM, Delneste Y. The outer membrane protein X from Escherichia coli exhibits immune properties. Vaccine 2003; 21:3765-74. [PMID: 12922110 DOI: 10.1016/s0264-410x(03)00316-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Outer membrane proteins (OMP) are expressed in Gram-negative bacterial cell wall. OmpA from Klebsiella pneumoniae (KpOmpA) has been shown to bind and to activate selectively antigen presenting cells (APCs), eliciting protective CTL responses. In this study, we investigated whether OmpX, another member of the OMP family and structurally related to OmpA, exhibits the same immune properties. Using recombinant OmpX from Escherichia coli (EcOmpX), we report that EcOmpX binds to and is internalized by human APCs. However, EcOmpX does not activate APCs. EcOmpX acts as an efficient carrier protein as it induces a potent and Th1/Th2 mixed anti-TNP humoral response. However, adjuvant is required to generate a protective anti-tumoral immune response in mice injected with a tumor model antigen coupled to EcOmpX. Collectively, these data show that EcOmpX is recognized by innate cells but does not activate them, suggesting that EcOmpX does not provide a signal danger to APCs. In conclusion, this study provides information on the molecular mechanisms involved in the recognition and activation of innate cells by bacterial outer membrane proteins.
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Affiliation(s)
- Karine Maisnier-Patin
- Centre d'Immunologie Pierre Fabre, 5 Avenue Napoléon III, 74160 Saint Julien en Genevois, France
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31
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Radford KJ, Jackson AM, Wang JH, Vassaux G, Lemoine NR. Recombinant E. coli efficiently delivers antigen and maturation signals to human dendritic cells: presentation of MART1 to CD8+ T cells. Int J Cancer 2003; 105:811-9. [PMID: 12767067 DOI: 10.1002/ijc.11149] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The generation of tumour-specific cytotoxic T-lymphocyte (CTL) responses is the primary focus in the design of immunotherapeutic cancer vaccines. We have recently demonstrated generation of ovalbumin (OVA)-specific CTLs and tumour-protection in a murine tumour model using vaccination with dendritic cells (DCs) pulsed with E. coli expressing listeriolysin O (LLO) and OVA as a model antigen. In this system paraformaldehyde fixation of E. coli/LLO provided an additional safety feature without compromising vaccine efficacy. We therefore reasoned that paraformaldehyde-fixed recombinant E. coli expressing LLO would be an efficient vehicle for the delivery of human tumour antigens to human DCs. In the present study, we demonstrate that fixed E. coli expressing LLO are taken up efficiently by human monocyte-derived DCs (MoDCs) with minimal toxicity. As a consequence of the interaction with bacteria, human DCs undergo marked phenotypic and functional maturation. Furthermore, we show that fixed E. coli/LLO expressing the well-characterised human melanoma antigen, MART1, efficiently deliver the HLA-A2-restricted MART1(27-35) epitope for processing and presentation on human MoDCs, suggesting the potential of this system as a novel strategy for human tumour immunotherapy.
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Affiliation(s)
- Kristen J Radford
- Cancer Research UK Molecular Oncology Unit, Imperial College London, Hammersmith Hospital, London, United Kingdom
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32
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Abstract
Anthrax toxin is a binary A-B toxin comprised of protective antigen (PA) and two enzymatic moieties, edema factor (EF) and lethal factor (LF). In the presence of a host cell-surface receptor, PA can mediate the delivery of EF and LF from the extracellular milieu into the host cell cytosol to effect toxicity. In this delivery, PA undergoes multiple structural changes--from a monomer to a heptameric prepore to a membrane-spanning heptameric pore. The catalytic factors also undergo dramatic structural changes as they unfold to allow for their translocation across the endosomal membrane and refold to preserve their catalytic activity within the cytosol. In addition to these gross structural changes, the intoxication mechanism depends on the ability of PA to form specific interactions with the host cell receptor, EF, and LF. This chapter presents a review of experiments probing these structural interactions and rearrangements in the hopes of gaining a molecular understanding of toxin action.
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Affiliation(s)
- D B Lacy
- Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115, USA
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33
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El Azami El Idrissi M, Ladant D, Leclerc C. The adenylate cyclase of Bordetella pertussis: a vector to target antigen presenting cells. Toxicon 2002; 40:1661-5. [PMID: 12457876 DOI: 10.1016/s0041-0101(02)00205-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M El Azami El Idrissi
- Unité de Biologie des Régulations Immunitaires, Institut Pasteur, 25 rue du Docteur Roux, 75724 Paris 15, France
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34
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Delneste Y, Magistrelli G, Gauchat J, Haeuw J, Aubry J, Nakamura K, Kawakami-Honda N, Goetsch L, Sawamura T, Bonnefoy J, Jeannin P. Involvement of LOX-1 in dendritic cell-mediated antigen cross-presentation. Immunity 2002; 17:353-62. [PMID: 12354387 DOI: 10.1016/s1074-7613(02)00388-6] [Citation(s) in RCA: 384] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Some exogenous antigens, such as heat shock proteins or apoptotic bodies, gain access to the MHC class I processing pathway and initiate CTL responses, a process called cross-priming. To be efficient in vivo, this process requires endocytosis of the antigen by dendritic cells via receptors which remain unidentified. Here, we report that scavenger receptors are the main HSP binding structures on human dendritic cells and identify LOX-1 as one of these molecules. A neutralizing anti-LOX-1 mAb inhibits Hsp70 binding to dendritic cells and Hsp70-induced antigen cross-presentation. In vivo, to target LOX-1 with a tumor antigen using an anti-LOX-1 mAb induces antitumor immunity. Thus, the scavenger receptor LOX-1 is certainly a promising target for cancer immunotherapy.
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Affiliation(s)
- Yves Delneste
- Centre d'Immunologie Pierre Fabre, 5 avenue Napoléon III, Saint Julien en Genevois, France
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35
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Alexander J, Oseroff C, Dahlberg C, Qin M, Ishioka G, Beebe M, Fikes J, Newman M, Chesnut RW, Morton PA, Fok K, Appella E, Sette A. A decaepitope polypeptide primes for multiple CD8+ IFN-gamma and Th lymphocyte responses: evaluation of multiepitope polypeptides as a mode for vaccine delivery. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 168:6189-98. [PMID: 12055232 DOI: 10.4049/jimmunol.168.12.6189] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Proteins are generally regarded as ineffective immunogens for CTL responses. We synthesized a 100-mer decaepitope polypeptide and tested its capacity to induce multiple CD8(+) IFN-gamma and Th lymphocyte (HTL) responses in HLA transgenic mice. Following a single immunization in the absence of adjuvant, significant IFN-gamma in vitro recall responses were detected for all epitopes included in the construct (six A2.1-, three A11-restricted CTL epitopes, and one universal HTL epitope). Immunization with truncated forms of the decaepitope polypeptide was used to demonstrate that optimal immunogenicity was associated with a size of at least 30-40 residues (3-4 epitopes). Solubility analyses of the truncated constructs were used to identify a correlation between immunogenicity for IFN-gamma responses and the propensity of these constructs to form particulate aggregates. Although the decaepitope polypeptide and a pool of epitopes emulsified in IFA elicited similar levels of CD8(+) responses using fresh splenocytes, we found that the decaepitope polypeptide more effectively primed for in vitro recall CD8(+) T cell responses. Finally, immunogenicity comparisons were also made between the decaepitope polypeptide and a corresponding gene encoding the same polypeptide delivered by naked DNA immunization. Although naked DNA immunization induced somewhat greater direct ex vivo and in vitro recall responses 2 wk after a single immunization, only the polypeptide induced significant in vitro recall responses 6 wk following the priming immunization. These studies support further evaluation of multiepitope polypeptide vaccines for induction of CD8(+) IFN-gamma and HTL responses.
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MESH Headings
- Animals
- Buffers
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- DNA/administration & dosage
- DNA/immunology
- Drug Contamination
- Emulsions
- Epitopes, T-Lymphocyte/administration & dosage
- Epitopes, T-Lymphocyte/chemistry
- Epitopes, T-Lymphocyte/immunology
- Freund's Adjuvant/immunology
- HLA Antigens/genetics
- HLA Antigens/immunology
- Humans
- Injections, Intramuscular
- Injections, Subcutaneous
- Interferon-gamma/biosynthesis
- Jurkat Cells
- Lymphocyte Activation
- Mice
- Mice, Inbred BALB C
- Mice, Transgenic
- Peptide Fragments/administration & dosage
- Peptide Fragments/chemical synthesis
- Peptide Fragments/immunology
- Solubility
- T-Lymphocytes, Helper-Inducer/immunology
- T-Lymphocytes, Helper-Inducer/metabolism
- Transgenes/immunology
- Vaccination/methods
- Vaccines, Synthetic/administration & dosage
- Vaccines, Synthetic/immunology
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36
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Corinti S, Chiarantini L, Dominici S, Laguardia ME, Magnani M, Girolomoni G. Erythrocytes deliver Tat to interferon‐γ‐treated human dendritic cells for efficient initiation of specific type 1 immune responses in vitro. J Leukoc Biol 2002. [DOI: 10.1189/jlb.71.4.652] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Affiliation(s)
- Silvia Corinti
- Laboratory of Immunology, Istituto Dermopatico dell’Immacolata, IRCCS, Rome, Italy; and
| | - Laura Chiarantini
- Institute of Biochemistry Giorgio Fornaini, University of Urbino, Italy
| | - Sabrina Dominici
- Institute of Biochemistry Giorgio Fornaini, University of Urbino, Italy
| | | | - Mauro Magnani
- Institute of Biochemistry Giorgio Fornaini, University of Urbino, Italy
| | - Giampiero Girolomoni
- Laboratory of Immunology, Istituto Dermopatico dell’Immacolata, IRCCS, Rome, Italy; and
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37
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Moriya O, Matsui M, Osorio M, Miyazawa H, Rice CM, Feinstone SM, Leppla SH, Keith JM, Akatsuka T. Induction of hepatitis C virus-specific cytotoxic T lymphocytes in mice by immunization with dendritic cells treated with an anthrax toxin fusion protein. Vaccine 2001; 20:789-96. [PMID: 11738742 DOI: 10.1016/s0264-410x(01)00407-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
As a novel and safe vaccine strategy, the anthrax toxin-mediated antigen delivery system composed of lethal factor (LF) fusion protein and protective antigen (PA) has been studied to prime hepatitis C virus (HCV) core-specific cytotoxic T lymphocytes (CTLs) in vivo. The core epitope fused to LF (LF-core) together with PA induces a negligible core-specific CTL response in mice, whereas core-specific CTL are effectively primed in mice by injecting dendritic cells (DCs) treated in vitro with LF-core and PA. These findings imply that LF fusion protein plus PA in combination with dendritic cells may be useful for a novel T cell vaccine against HCV infection.
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Affiliation(s)
- O Moriya
- Department of Microbiology, Saitama Medical School, Moroyama-Cho, Iruma-Gun, Saitama 350-0495, Japan
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38
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Gmira S, Karimova G, Ladant D. Characterization of recombinant Bordetella pertussis adenylate cyclase toxins carrying passenger proteins. Res Microbiol 2001; 152:889-900. [PMID: 11766964 DOI: 10.1016/s0923-2508(01)01272-4] [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: 11/16/2022]
Abstract
Bordetella pertussis secretes a calmodulin-activated adenylate cyclase toxin, CyaA, that is able to deliver its N-terminal catalytic domain (400 amino acid residues) into the cytosol of eukaryotic target cells, directly through the cytoplasmic membrane. We have previously shown that CyaA can be used as a vehicle to deliver CD8+ T-cell epitopes, inserted within the catalytic domain of the toxin, into antigen-presenting cells and can trigger specific class I-restricted cytotoxic T-cell (CTL) responses in vivo. To explore the tolerance of CyaA to insertion of polypeptides of larger size, we constructed and characterized different recombinant CyaA toxins with protein inserts of 87 to 206 amino acids in length. Several of these recombinant CyaA toxins were found to be invasive. Furthermore, we showed that the unfolding of the passenger protein is a prerequisite for the translocation of the recombinant toxins into eukaryotic cells. Our results highlight the remarkable tolerance of the CyaA toxin and suggest that CyaA might be used to deliver proteins into eukaryotic cells.
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Affiliation(s)
- S Gmira
- Unité de Biochimie Cellulaire, CNRS URA 2185, Institut Pasteur, Paris, France
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39
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Facchini LM, Lingwood CA. A verotoxin 1 B subunit-lambda CRO chimeric protein specifically binds both DNA and globotriaosylceramide (Gb(3)) to effect nuclear targeting of exogenous DNA in Gb(3) positive cells. Exp Cell Res 2001; 269:117-29. [PMID: 11525645 DOI: 10.1006/excr.2001.5297] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Inefficient nuclear incorporation of foreign DNA remains a critical roadblock in the development of effective nonviral gene delivery systems. DNA delivered by traditional protocols remains within endosomal/lysosomal vesicles, or is rapidly degraded in the cytoplasm. Verotoxin I (VT), an AB(5) subunit toxin produced by enterohaemorrhagic Escherichia coli, binds to the cell surface glycolipid, globotriaosylceramide (Gb(3)) and is internalized into preendosomes. VT is then retrograde transported to the Golgi, endoplasmic reticulum (ER), and nucleus of highly VT-sensitive cells. We have utilized this nuclear targeting of VT to design a unique delivery system which transports exogenous DNA via vesicular traffic to the nucleus. The nontoxic VT binding subunit (VTB) was fused to the lambda Cro DNA-binding repressor, generating a 14-kDa VTB-Cro chimera. VTB-Cro binds specifically via the Cro domain to a 25-bp DNA fragment containing the consensus Cro operator. VTB-Cro demonstrates simultaneous specific binding to Gb(3). Treatment of Vero cells with fluorescent-labeled Cro operator DNA in the presence of VTB-Cro, results in DNA internalization to the Golgi, ER, and nucleus, whereas fluorescent DNA alone is incorporated poorly and randomly within the cytoplasm. VTB-Cro mediated nuclear DNA transport is prevented by brefeldin A, consistent with Golgi/ER intracellular routing. Pretreatment with filipin had no effect, indicating that caveoli are not involved. This novel VTB-Cro shuttle protein may find practical applications in the fields of intracellular targeting, gene delivery, and gene therapy.
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Affiliation(s)
- L M Facchini
- Division of Infection, Immunity, Injury and Repair, Research Institute, University of Toronto, Toronto, Canada
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40
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Sarr AD, Lu Y, Sankalé JL, Eisen G, Popper S, Mboup S, Kanki PJ, Cao H. Robust HIV type 2 cellular immune response measured by a modified anthrax toxin-based enzyme-linked immunospot assay. AIDS Res Hum Retroviruses 2001; 17:1257-64. [PMID: 11559425 DOI: 10.1089/088922201750461311] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Evaluation of immune mechanisms responsible for control of viral replication is critical to understanding HIV-2 attenuated biological characteristics in pathogenesis and transmission. Evaluation of the cellular immune response is often based on labor-intensive techniques that limit the scope of most studies performed. A simple and rapid anthrax toxin-based ELISPOT method to assess HIV-2 cellular immune response was developed. The modified anthrax toxin-based antigen presentation process performed better than a recombinant vaccinia system and the ELISPOT method significantly enhanced the ease and simplicity of the assay. Using this method, a robust HIV-2 cellular immune response directed toward the p26 core protein was exhibited in 21 of 24 (87.5%) infected women, and all 8 seronegative subjects were negative in both assays. Cellular immune responses were associated with low HIV-2 viral load. This simple and rapid modified anthrax toxin-based ELISPOT method allowed us to demonstrate, strong cellular immune responses that may be critical determinants in the HIV-2 attenuated phenotype.
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Affiliation(s)
- A D Sarr
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts 02115, USA
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41
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Affiliation(s)
- C W Cutler
- Department of Periodontics, School of Dental Medicine, State University of New York-Stony Brook, Stony Brook, 11794-8703, USA.
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42
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Reay PA. Dendritic cells: immunological features and utilisation for tumour immunotherapy. Expert Opin Ther Targets 2001; 5:491-506. [PMID: 12540262 DOI: 10.1517/14728222.5.4.491] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The prospect of developing 'magic bullets' to attack tumour cells has been a goal of biologists for decades. Abundant experimental and clinical observations demonstrating that an effective specific immune response may engender tumour regression has prompted efforts to find an immunotherapeutic approach to this problem. The most important arm of cellular immunity for such responses appears to be cytotoxic T-lymphocytes (CTL) which can recognise antigen on virtually all cell types and which are key to the elimination of virally-infected cells. The specific activation and maintenance of activity of these cells is therefore the major goal of designing a therapeutic cancer vaccine. Advances in our understanding of the role of dendritic cells (DC) in priming and modifying immune responses suggest that they should be potent adjuvants for vaccination. The use of antigens targeted to the major histocompatibility complex (MHC) molecules expressed on these cells as an approach to tumour immunotherapy has already been tested in the treatment of many malignancies, and recent findings shed light on additional directions through which their efficacy may be improved.
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Affiliation(s)
- Philip A Reay
- Nuffield Department of Clinical Medicine, University of Oxford, John Radcliffe Hospital II, Headington, OX3 9DU, UK.
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43
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Maecker HT, Ghanekar SA, Suni MA, He XS, Picker LJ, Maino VC. Factors affecting the efficiency of CD8+ T cell cross-priming with exogenous antigens. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:7268-75. [PMID: 11390476 DOI: 10.4049/jimmunol.166.12.7268] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Processing of exogenous protein Ags by APC leads predominantly to presentation of peptides on class II MHC and, thus, stimulation of CD4+ T cell responses. However, "cross-priming" can also occur, whereby peptides derived from exogenous Ags become displayed on class I MHC molecules and stimulate CD8+ T cell responses. We compared the efficiency of cross-priming with exogenous proteins to use of peptide Ags in human whole blood using a flow cytometry assay to detect T cell intracellular cytokine production. CD8+ T cell responses to whole CMV proteins were poorly detected (compared with peptide responses) in most CMV-seropositive donors. Such responses could be increased by using higher doses of Ag than were required to achieve maximal CD4+ T cell responses. A minority of donors displayed significantly more efficient CD8+ T cell responses to whole protein, even at low Ag doses. These responses were MHC class I-restricted and dependent upon proteosomal processing, indicating that they were indeed due to cross-priming. The ability to efficiently cross-prime was not a function of the number of dendritic cells in the donor's blood. Neither supplementation of freshly isolated dendritic cells nor use of cultured, Ag-pulsed dendritic cells could significantly boost CD8 responses to whole-protein Ags in poorly cross-priming donors. Interestingly, freshly isolated monocytes performed almost as well as dendritic cells in inducing CD8 responses via cross-priming. In conclusion, the efficiency of cross-priming appears to be poor in most donors and is dependent upon properties of the individual's APC and/or T cell repertoire. It remains unknown whether cross-priming ability translates into any clinical advantage in ability to induce CD8+ T cell responses to foreign Ags.
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Affiliation(s)
- H T Maecker
- BD Immunocytometry Systems, San Jose, CA 95131, USA.
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44
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Chauhan V, Singh A, Waheed SM, Singh S, Bhatnagar R. Constitutive expression of protective antigen gene of Bacillus anthracis in Escherichia coli. Biochem Biophys Res Commun 2001; 283:308-15. [PMID: 11327699 DOI: 10.1006/bbrc.2001.4777] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The fatal bacterial infection caused by inhalation of the Bacillus anthracis spores results from the synthesis of protein toxins-protective antigen (PA), lethal factor (LF), and edema factor (EF)--by the bacterium. PA is the target-cell binding protein and is common to the two effector molecules, LF and EF, which exert their toxic effects once they are translocated to the cytosol by PA. PA is the major component of vaccines against anthrax since it confers protective immunity. The large-scale production of recombinant protein-based anthrax vaccines requires overexpression of the PA protein. We have constitutively expressed the protective antigen protein in E. coli DH5alpha strain. We have found no increase in degradation of PA when the protein is constitutively expressed and no plasmid instability was observed inside the expressing cells. We have also scaled up the expression by bioprocess optimization using batch culture technique in a fermentor. The protein was purified using metal-chelate affinity chromatography. Approximately 125 mg of recombinant protective antigen (rPA) protein was obtained per liter of batch culture. It was found to be biologically and functionally fully active in comparison to PA protein from Bacillus anthracis. This is the first report of constitutive overexpression of protective antigen gene in E. coli.
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Affiliation(s)
- V Chauhan
- Centre For Biotechnology, Jawaharlal Nehru University, New Delhi, 110067, India
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45
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Guermonprez P, Fayolle C, Karimova G, Ullmann A, Leclerc C, Ladant D. Bordetella pertussis adenylate cyclase toxin: a vehicle to deliver CD8-positive T-cell epitopes into antigen-presenting cells. Methods Enzymol 2001; 326:527-42. [PMID: 11036662 DOI: 10.1016/s0076-6879(00)26074-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
MESH Headings
- Adenylate Cyclase Toxin
- Adenylyl Cyclases/metabolism
- Amino Acid Sequence
- Animals
- Antigen-Presenting Cells/immunology
- Artificial Gene Fusion
- Bacterial Proteins/genetics
- Bacterial Proteins/isolation & purification
- Base Sequence
- Bordetella pertussis/genetics
- CD8-Positive T-Lymphocytes/immunology
- Chickens
- Cytotoxicity, Immunologic
- Epitopes/genetics
- Female
- Genes, Reporter
- Macrophages, Peritoneal/immunology
- Melanoma, Experimental/genetics
- Melanoma, Experimental/immunology
- Melanoma, Experimental/therapy
- Mice
- Mice, Inbred C57BL
- Molecular Sequence Data
- Ovalbumin/immunology
- Protein Precursors/genetics
- Protein Precursors/isolation & purification
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/isolation & purification
- Recombinant Proteins/biosynthesis
- Recombinant Proteins/isolation & purification
- T-Lymphocytes, Cytotoxic/immunology
- Transfection
- Tumor Cells, Cultured
- Virulence Factors, Bordetella/genetics
- Virulence Factors, Bordetella/isolation & purification
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Affiliation(s)
- P Guermonprez
- Unité de Biologie des Régulations Immunitaires, CNRS URA 2185, Institut Pasteur, Paris, France
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46
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Dietrich G, Hess J, Gentschev I, Knapp B, Kaufmann SH, Goebel W. From evil to good: a cytolysin in vaccine development. Trends Microbiol 2001; 9:23-8. [PMID: 11166239 DOI: 10.1016/s0966-842x(00)01893-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Current vaccination strategies mainly target antigens into the phagosomal, major histocompatibility complex class II antigen-processing pathway and thus lead predominantly to humoral immune responses. The elicitation of cytotoxic T-cell responses instead requires introduction of antigens into the cytosol of professional antigen-presenting cells (APCs). The intracellular bacterium Listeria monocytogenes gains access to the host cell cytosol by means of a cytolysin, listeriolysin O. Vaccine researchers have successfully employed listeriolysin in novel vaccination approaches to provide access to the cytosol of professional APCs for purified protein antigens, attenuated bacterial vaccine strains, DNA vaccines and liposome contents.
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Affiliation(s)
- G Dietrich
- Department of Microbiology, University of Würzburg, D-97074 Würzburg, Germany.
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47
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Tirosh B, Fridkin M, Tzehoval E, Vadai E, Lemonnier FA, Eisenbach L. Antigenicity and immunogenicity of an intracellular delivery system of major histocompatibility complex class I epitopes that bypasses proteasome processing. J Immunother 2000; 23:622-30. [PMID: 11186150 DOI: 10.1097/00002371-200011000-00003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The development of a cell-free synthetic vaccine to induce an effective cytotoxic T lymphocyte response is an important challenge in T-cell--mediated immunity. Because standard vaccinations with nominal epitopes were found to be only partially effective in vivo, the authors suggest an alternative strategy: the delivery of epitopes directly to the cell cytosol in a proteasome bypass mechanism of processing. Two model peptides, the presentation level on the cell surface of which can be directly assessed, were conjugated via a cross-linker to an internalization peptide derived from an antennapedia homeobox protein. The linker was designed to undergo spontaneous hydrolysis, after which the epitope is subsequently released. The conjugates were shown to enter RMA and P815 cells, where the epitopes were released mainly in cytosol and endogenously loaded on the major histocompatibility complex class I molecules to be presented on the cell surface. Concomitant inhibition of proteasome activity by MG132 significantly increased the presentation level of both model peptides, indicating proteasome-independent processing. This phenomenon was exploited to enhance the immunogenicity of the conjugates. Conjugates were emulsified with MG132 in incomplete Freund's adjuvant and injected into mouse footpads. Analysis of the draining lymph nodes indicated an increase in the percentage of both CD4+ and CD8+ lymphocytes. In vitro cytolytic assays implied significant, albeit moderate, priming only when the proteasome inhibitor was administered with the conjugate. This approach may be useful for the development of efficient synthetic cell-free vaccines.
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Affiliation(s)
- B Tirosh
- Department of Immunology, The Weizmann Institute of Science, Rehovot, Israel
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48
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Abstract
The potential to harness the potency and specificity of the immune system underlies the growing interest in cancer immunotherapy. One such approach uses bone marrow-derived dendritic cells, phenotypically distinct and extremely potent antigen-presenting cells, to present tumor-associated antigens and thereby generate tumor-specific immunity. Support for this strategy comes from animal studies that have demonstrated that dendritic cells, when loaded ex vivo with tumor antigens and administered to tumor-bearing hosts, can elicit T cell-mediated tumor destruction. These observations have led to clinical trials designed to investigate the immunologic and clinical effects of antigen-loaded dendritic cells administered as a therapeutic vaccine to patients with cancer. In the design and conduct of such trials, important considerations include antigen selection, methods for introducing the antigen into MHC class I and II processing pathways, methods for isolating and activating dendritic cells, and route of administration. Although current dendritic cell-based vaccination methods are cumbersome, promising results from clinical trials in patients with malignant lymphoma, melanoma, and prostate cancer suggest that immunotherapeutic strategies that take advantage of the antigen presenting properties of dendritic cells may ultimately prove both efficacious and widely applicable to human tumors.
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Affiliation(s)
- L Fong
- Departments of Pathology and Medicine, Stanford University School of Medicine, Palo Alto, California 94304, USA.
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49
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Francis JW, Brown RH, Figueiredo D, Remington MP, Castillo O, Schwarzschild MA, Fishman PS, Murphy JR, vanderSpek JC. Enhancement of diphtheria toxin potency by replacement of the receptor binding domain with tetanus toxin C-fragment: a potential vector for delivering heterologous proteins to neurons. J Neurochem 2000; 74:2528-36. [PMID: 10820215 DOI: 10.1046/j.1471-4159.2000.0742528.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This study describes the expression, purification, and characterization of a recombinant fusion toxin, DAB(389)TTC, composed of the catalytic and membrane translocation domains of diphtheria toxin (DAB(389)) linked to the receptor binding fragment of tetanus toxin (C-fragment). As determined by its ability to inhibit cellular protein synthesis in primary neuron cultures, DAB(389)TTC was approximately 1,000-fold more cytotoxic than native diphtheria toxin or the previously described fusion toxin, DAB(389)MSH. The cytotoxic effect of DAB(389)TTC on cultured cells was specific toward neuronal-type cells and was blocked by coincubation of the chimeric toxin with tetanus antitoxin. The toxicity of DAB(389)TTC, like that of diphtheria toxin, was dependent on passage through an acidic compartment and ADP-ribosyltransferase activity of the DAB(389) catalytic fragment. These results suggest that a catalytically inactive form of DAB(389)TTC may be useful as a nonviral vehicle to deliver exogenous proteins to the cytosolic compartment of neurons.
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Affiliation(s)
- J W Francis
- Cecil B. Day Center for Neuromuscular Research, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA.
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50
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Ulrich JT, Cieplak W, Paczkowski NJ, Taylor SM, Sanderson SD. Induction of an antigen-specific CTL response by a conformationally biased agonist of human C5a anaphylatoxin as a molecular adjuvant. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 164:5492-8. [PMID: 10799917 DOI: 10.4049/jimmunol.164.10.5492] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A conformationally biased decapeptide agonist of human C5a anaphylatoxin (YSFKPMPLaR) was used as a molecular adjuvant in stimulating an Ag-specific CTL response against murine P815S target cells expressing an Ld-restricted CTL epitope of the hepatitis B surface Ag (HBsAg). Groups of BALB/c mice (H-2d) were immunized with aqueous solutions of the HBsAg CTL epitopes (IPQSLDSWWTSL and IPQSLDSWWTSLRR); the C5a agonist (YSFKPMPLaR); the C5a agonist and HBsAg CTL epitopes admixed (IPQSLDSWWTSL and IPQSLDSWWTSLRR + YSFKPMPLaR); the C5a-active, HBsAg CTL epitope-C5a agonist constructs (IPQSLDSWWTSLYSFKPMPLaR, IPQSLDSWWTSLRRYSFKPMPLaR, and IPQSLDSWWTSLRVRRYSFPMPLaR); a C5a-inactive, reverse-moiety construct (YSFKPMPLaRRRIPQSLDSWWTSL); and a C5a-attenuated, carboxyl-terminal-blocked construct (IPQSLDSWWTSLRRYSFKPMPLaRG). Ag-specific CD8+ CTL responses were observed after the secondary boost in the absence of any added adjuvant only in mice that were immunized with C5a-active contructs, IPQSLDSWWTSLRRYSFKPMPLaR and IPQSLDSWWTSLRVRRYSFKPMPLaR. These two C5a-active immunogens contained potential subtilisin-sensitive linker sequences between the HBsAg CTL epitope and the C5a agonist; i.e., a double-Arg (RR) and a furin protease sensitive sequence (RVRR). The introduction of these potentially cleavable sequences may be a method of increasing the likelihood of liberating the CTL epitope from the C5a agonist by intracellular proteases, thereby facilitating entry of the epitope into Ag-processing pathways via an exogenous route.
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MESH Headings
- Adjuvants, Immunologic/administration & dosage
- Adjuvants, Immunologic/agonists
- Adjuvants, Immunologic/chemistry
- Adjuvants, Immunologic/pharmacology
- Amino Acid Sequence
- Animals
- Arginine/administration & dosage
- Arginine/chemistry
- Arginine/immunology
- Cells, Cultured
- Complement C5a/administration & dosage
- Complement C5a/agonists
- Complement C5a/chemistry
- Complement C5a/immunology
- Cytotoxicity, Immunologic
- Endopeptidases/chemistry
- Endopeptidases/immunology
- Epitopes, T-Lymphocyte/administration & dosage
- Epitopes, T-Lymphocyte/chemistry
- Epitopes, T-Lymphocyte/immunology
- Female
- H-2 Antigens/administration & dosage
- H-2 Antigens/chemistry
- H-2 Antigens/immunology
- Hepatitis B Antibodies/biosynthesis
- Hepatitis B Surface Antigens/administration & dosage
- Hepatitis B Surface Antigens/immunology
- Histocompatibility Antigen H-2D
- Humans
- Injections, Subcutaneous
- Lymphocyte Activation
- Mice
- Mice, Inbred BALB C
- Molecular Sequence Data
- Peptide Fragments/administration & dosage
- Peptide Fragments/chemical synthesis
- Peptide Fragments/immunology
- Peptide Fragments/pharmacology
- Protein Conformation
- T-Lymphocytes, Cytotoxic/immunology
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