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Jones RA, Jerse AE, Tang CM. Gonococcal PorB: a multifaceted modulator of host immune responses. Trends Microbiol 2024; 32:355-364. [PMID: 37891023 DOI: 10.1016/j.tim.2023.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 09/28/2023] [Accepted: 10/03/2023] [Indexed: 10/29/2023]
Abstract
Neisseria gonorrhoeae is a human-specific pathogen responsible for the sexually transmitted infection, gonorrhoea. N. gonorrhoeae promotes its survival by manipulating both innate and adaptive immune responses. The most abundant gonococcal outer-membrane protein is PorB, an essential porin that facilitates ion exchange. Importantly, gonococcal PorB has several immunomodulatory properties. To subvert the innate immune response, PorB suppresses killing mechanisms of macrophages and neutrophils, and recruits negative regulators of complement to the gonococcal cell surface. For manipulation of adaptive immune responses, gonococcal PorB suppresses the capability of dendritic cells to stimulate proliferation of T cells. As gonococcal PorB is highly abundant in outer-membrane vesicles, consideration of the immunomodulatory properties of this porin is critical when designing gonococcal vaccines.
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Affiliation(s)
- Rebekah A Jones
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Ann E Jerse
- Department of Microbiology and Immunology, Uniformed Services University, Bethesda, MD, USA
| | - Christoph M Tang
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK.
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2
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Ma W, Wang X, Zhang W, Hu X, Yang JL, Liang X. Two-Component System Response Regulator ompR Regulates Mussel Settlement through Exopolysaccharides. Int J Mol Sci 2023; 24:ijms24087474. [PMID: 37108636 PMCID: PMC10139040 DOI: 10.3390/ijms24087474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 04/12/2023] [Accepted: 04/14/2023] [Indexed: 04/29/2023] Open
Abstract
The outer membrane protein (OMP) is a kind of biofilm matrix component that widely exists in Gram-negative bacteria. However, the mechanism of OMP involved in the settlement of molluscs is still unclear. In this study, the mussel Mytilus coruscus was selected as a model to explore the function of ompR, a two-component system response regulator, on Pseudoalteromonas marina biofilm-forming capacity and the mussel settlement. The motility of the ΔompR strain was increased, the biofilm-forming capacity was decreased, and the inducing activity of the ΔompR biofilms in plantigrades decreased significantly (p < 0.05). The extracellular α-polysaccharide and β-polysaccharide of the ΔompR strain decreased by 57.27% and 62.63%, respectively. The inactivation of the ompR gene decreased the ompW gene expression and had no impact on envZ expression or c-di-GMP levels. Adding recombinant OmpW protein caused the recovery of biofilm-inducing activities, accompanied by the upregulation of exopolysaccharides. The findings deepen the understanding of the regulatory mechanism of bacterial two-component systems and the settlement of benthic animals.
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Affiliation(s)
- Wei Ma
- International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Collaborative Innovation Center for Cultivating Elite Breeds and Green-Culture of Aquaculture Animals, Shanghai 201306, China
| | - Xiaoyu Wang
- International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Collaborative Innovation Center for Cultivating Elite Breeds and Green-Culture of Aquaculture Animals, Shanghai 201306, China
| | - Wen Zhang
- International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Collaborative Innovation Center for Cultivating Elite Breeds and Green-Culture of Aquaculture Animals, Shanghai 201306, China
| | - Xiaomeng Hu
- International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Collaborative Innovation Center for Cultivating Elite Breeds and Green-Culture of Aquaculture Animals, Shanghai 201306, China
| | - Jin-Long Yang
- International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Collaborative Innovation Center for Cultivating Elite Breeds and Green-Culture of Aquaculture Animals, Shanghai 201306, China
| | - Xiao Liang
- International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Collaborative Innovation Center for Cultivating Elite Breeds and Green-Culture of Aquaculture Animals, Shanghai 201306, China
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Sharma A, Yadav SP, Sarma D, Mukhopadhaya A. Modulation of host cellular responses by gram-negative bacterial porins. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2021; 128:35-77. [PMID: 35034723 DOI: 10.1016/bs.apcsb.2021.09.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The outer membrane of a gram-negative bacteria encapsulates the plasma membrane thereby protecting it from the harsh external environment. This membrane acts as a sieving barrier due to the presence of special membrane-spanning proteins called "porins." These porins are β-barrel channel proteins that allow the passive transport of hydrophilic molecules and are impermeable to large and charged molecules. Many porins form trimers in the outer membrane. They are abundantly present on the bacterial surface and therefore play various significant roles in the host-bacteria interactions. These include the roles of porins in the adhesion and virulence mechanisms necessary for the pathogenesis, along with providing resistance to the bacteria against the antimicrobial substances. They also act as the receptors for phage and complement proteins and are involved in modulating the host cellular responses. In addition, the potential use of porins as adjuvants, vaccine candidates, therapeutic targets, and biomarkers is now being exploited. In this review, we focus briefly on the structure of the porins along with their important functions and roles in the host-bacteria interactions.
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Affiliation(s)
- Arpita Sharma
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Mohali, Punjab, India
| | - Shashi Prakash Yadav
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Mohali, Punjab, India
| | - Dwipjyoti Sarma
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Mohali, Punjab, India
| | - Arunika Mukhopadhaya
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Mohali, Punjab, India.
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Yang R, Tao Y, Li G, Chen J, Shu J, He Y. Immunoenhancement of Recombinant Neisseria meningitides PorB Protein on Porcine Circovirus Type 2 and Mycoplasma hyopneumoniae Genetically Engineered Vaccines. Protein Pept Lett 2019; 26:776-784. [PMID: 31208304 DOI: 10.2174/0929866526666190430115052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 04/08/2019] [Accepted: 04/09/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Porcine circovirus and Mycoplasma hyopneumoniae can cause respiratory diseases in pigs, which cause serious economic loss in the worldwide pig industry. Currently, these infections are mainly prevented and controlled by vaccination. The new vaccines on the market are mainly composed of subunits and inactivated vaccines but usually have lower antigenicity than traditional live vaccines. Thus, there is an increasing need to develop new adjuvants that can cause rapid and long-lasting immunity to enhance the antigenic efficacy for vaccines. Studies have shown that meningococcal porin PorB can act as a ligand to combine with Toll-like receptors to activate the production of immunological projections and act as a vaccine immunological adjuvant. OBJECTIVE In this article, we expressed and purified the recombinant PorB protein and verified its immunogenicity against porcine circovirus type 2 and Mycoplasma hyopneumoniae genetically engineered vaccine. METHODS In this article, we used prokaryotic expression to express and purify recombinant PorB protein, four different concentrations of PorB protein, Freund's adjuvant with two genetically engineered vaccines were combined with subcutaneous immunization of mice. RESULTS Our study shows that the appropriate dose of the recombinant protein PorB can enhance the levels of humoral and cellular responses induced by two genetically engineered vaccines in a short period of time in mice. The PorB adjuvant group may cause statistically higher antibody titers for both genetically engineered vaccines compared to Freund's commercial adjuvant (P<0.001). CONCLUSION The recombinant protein PorB may be a good candidate adjuvant for improving the protective effect of vaccines against porcine circovirus type 2 and Mycoplasma hyopneumoniae, and the protein can be used for future practical applications.
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Affiliation(s)
- Rui Yang
- College of Life Sciences and Medicine, Zhejiang Provincial Key Laboratory of Silkworm Bioreactor and Biomedicine, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Yu Tao
- College of Life Sciences and Medicine, Zhejiang Provincial Key Laboratory of Silkworm Bioreactor and Biomedicine, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Gaojian Li
- College of Life Sciences and Medicine, Zhejiang Provincial Key Laboratory of Silkworm Bioreactor and Biomedicine, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Jian Chen
- College of Life Sciences and Medicine, Zhejiang Provincial Key Laboratory of Silkworm Bioreactor and Biomedicine, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Jianhong Shu
- College of Life Sciences and Medicine, Zhejiang Provincial Key Laboratory of Silkworm Bioreactor and Biomedicine, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Yulong He
- College of Life Sciences and Medicine, Zhejiang Provincial Key Laboratory of Silkworm Bioreactor and Biomedicine, Zhejiang Sci-Tech University, Hangzhou 310018, China
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5
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The Role of Meningococcal Porin B in Protein-Protein Interactions with Host Cells. FOLIA VETERINARIA 2018. [DOI: 10.2478/fv-2018-0008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Neisseria meningitidis is a Gram-negative diplococcus responsible for bacterial meningitis and fatal sepsis. Ligand-receptor interactions are one of the main steps in the development of neuroinvasion. Porin B (PorB), neisserial outer membrane protein (ligand), binds to host receptors and triggers many cell signalling cascades allowing the meningococcus to damage the host cells or induce immune cells responses via the TLR2-dependent mechanisms. In this paper, we present a brief review of the structure and function of PorB.
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Reiser ML, Mosaheb MM, Lisk C, Platt A, Wetzler LM. The TLR2 Binding Neisserial Porin PorB Enhances Antigen Presenting Cell Trafficking and Cross-presentation. Sci Rep 2017; 7:736. [PMID: 28389664 PMCID: PMC5428659 DOI: 10.1038/s41598-017-00555-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 03/03/2017] [Indexed: 01/06/2023] Open
Abstract
TOLL-like receptor (TLR) ligands activate both innate and adaptive immune cells, while modulating the cellular immune response. The outer membrane protein (OMP) from Neisseria meninigitidis, PorB, is a naturally occurring TLR2 ligand and functions as an adjuvant. Here, we demonstrate that PorB increases the level of OVA in the endo-/lysosomal cellular compartment of BMDCs, increases antigen presenting cell (APC) trafficking to draining lymph nodes, and enhances antigen cross-presentation. PorB is capable of mounting an antigen specific T cell response by efficiently stimulating antigen cross-presentation in vivo and in vitro assessed by BMDC OT-I cocultivation assays. The enhanced antigen cross-presentation and the increased APC recruitment to secondary lymphoid tissues expand the scope of known adjuvant effects of PorB on the immune system. Our findings lead to a better understanding of how TLR-ligand based adjuvants can alter and modulate immune responses.
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Affiliation(s)
- Michael L Reiser
- Section of Infectious Diseases, Department of Medicine, Boston Medical Center, Boston, USA
| | - Munir M Mosaheb
- Department of Microbiology, Boston University School of Medicine, Boston, USA
- Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, USA
| | - Christina Lisk
- Section of Infectious Diseases, Department of Medicine, Boston Medical Center, Boston, USA
| | - Andrew Platt
- Department of Microbiology, Boston University School of Medicine, Boston, USA
| | - Lee M Wetzler
- Department of Microbiology, Boston University School of Medicine, Boston, USA.
- Section of Infectious Diseases, Department of Medicine, Boston Medical Center, Boston, USA.
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7
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Pérez-Toledo M, Valero-Pacheco N, Pastelin-Palacios R, Gil-Cruz C, Perez-Shibayama C, Moreno-Eutimio MA, Becker I, Pérez-Tapia SM, Arriaga-Pizano L, Cunningham AF, Isibasi A, Bonifaz LC, López-Macías C. Salmonella Typhi Porins OmpC and OmpF Are Potent Adjuvants for T-Dependent and T-Independent Antigens. Front Immunol 2017; 8:230. [PMID: 28337196 PMCID: PMC5344031 DOI: 10.3389/fimmu.2017.00230] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 02/17/2017] [Indexed: 02/05/2023] Open
Abstract
Several microbial components, such as bacterial DNA and flagellin, have been used as experimental vaccine adjuvants because of their inherent capacity to efficiently activate innate immune responses. Likewise, our previous work has shown that the major Salmonella Typhi (S. Typhi) outer membrane proteins OmpC and OmpF (porins) are highly immunogenic protective antigens that efficiently stimulate innate and adaptive immune responses in the absence of exogenous adjuvants. Moreover, S. Typhi porins induce the expression of costimulatory molecules on antigen-presenting cells through toll-like receptor canonical signaling pathways. However, the potential of major S. Typhi porins to be used as vaccine adjuvants remains unknown. Here, we evaluated the adjuvant properties of S. Typhi porins against a range of experimental and clinically relevant antigens. Co-immunization of S. Typhi porins with ovalbumin (OVA), an otherwise poorly immunogenic antigen, enhanced anti-OVA IgG titers, antibody class switching, and affinity maturation. This adjuvant effect was dependent on CD4+ T-cell cooperation and was associated with an increase in IFN-γ, IL-17A, and IL-2 production by OVA-specific CD4+ T cells. Furthermore, co-immunization of S. Typhi porins with an inactivated H1N1 2009 pandemic influenza virus experimental vaccine elicited higher hemagglutinating anti-influenza IgG titers, antibody class switching, and affinity maturation. Unexpectedly, co-administration of S. Typhi porins with purified, unconjugated Vi capsular polysaccharide vaccine (Vi CPS)—a T-independent antigen—induced higher IgG antibody titers and class switching. Together, our results suggest that S. Typhi porins OmpC and OmpF are versatile vaccine adjuvants, which could be used to enhance T-cell immune responses toward a Th1/Th17 profile, while improving antibody responses to otherwise poorly immunogenic T-dependent and T-independent antigens.
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Affiliation(s)
- Marisol Pérez-Toledo
- Medical Research Unit on Immunochemistry, Specialties Hospital, National Medical Centre "Siglo XXI", Mexican Social Security Institute, Mexico City, Mexico; Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Nuriban Valero-Pacheco
- Medical Research Unit on Immunochemistry, Specialties Hospital, National Medical Centre "Siglo XXI", Mexican Social Security Institute, Mexico City, Mexico; Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | | | - Cristina Gil-Cruz
- Institute of Immunobiology, Kantonsspital St. Gallen , St. Gallen , Switzerland
| | | | - Mario A Moreno-Eutimio
- Immunity and Inflammation Research Unit, Hospital Juárez de México, Ministry of Health , Mexico City , Mexico
| | - Ingeborg Becker
- Facultad de Medicina, Departamento de Medicina Experimental, Universidad Nacional Autónoma de México , Mexico City , Mexico
| | - Sonia Mayra Pérez-Tapia
- Unit of R&D in Bioprocesses (UDIBI), Department of Immunology, National School of Biological Sciences, National Polytechnic Institute , Mexico City , Mexico
| | - Lourdes Arriaga-Pizano
- Medical Research Unit on Immunochemistry, Specialties Hospital, National Medical Centre "Siglo XXI", Mexican Social Security Institute , Mexico City , Mexico
| | - Adam F Cunningham
- MRC Centre for Immune Regulation, College of Medical and Dental Sciences, Institute of Immunology and Immunotherapy, University of Birmingham , Birmingham , UK
| | - Armando Isibasi
- Medical Research Unit on Immunochemistry, Specialties Hospital, National Medical Centre "Siglo XXI", Mexican Social Security Institute , Mexico City , Mexico
| | - Laura C Bonifaz
- Medical Research Unit on Immunochemistry, Specialties Hospital, National Medical Centre "Siglo XXI", Mexican Social Security Institute , Mexico City , Mexico
| | - Constantino López-Macías
- Medical Research Unit on Immunochemistry, Specialties Hospital, National Medical Centre "Siglo XXI", Mexican Social Security Institute, Mexico City, Mexico; Nuffield Department of Medicine, University of Oxford, Oxford, UK
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8
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Li X, Ni R. Breaking Hepatitis B Virus Tolerance and Inducing Protective Immunity Based on Mimicking T Cell-Independent Antigen. Viral Immunol 2016; 29:502-509. [PMID: 27662269 DOI: 10.1089/vim.2016.0052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
There are over 350 million chronic carriers of hepatitis B virus (HBV) in the world, of whom about a third eventually develop severe HBV-related complications. HBV contributes to liver cirrhosis and hepatocellular carcinoma development. Remarkable progress has been made in selective inhibition of HBV replication by nucleoside analogs. However, how to generate protective antibody of HBsAb in HBV-infected patients after HBV-DNA becomes negative still remains a challenge for scientists. In this study, we show that OmpC-HBsAg 'a' epitope chimeric protein vaccine can break HBV tolerance and induce protective immunity in HBV transgenic mice based on mimicking T cell-independent antigen to bypass T cells from the adaptive immune system. The antibodies induced by the vaccine have the ability to prevent HBV virion infection of human hepatocytes.
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Affiliation(s)
- Xiaoyan Li
- 1 Department of Gastroenterology, Affiliated Hospital of Nantong University , Nantong, China .,2 The Clinical Research Center, Affiliated Hospital of Nantong University , Nantong, China
| | - Runzhou Ni
- 1 Department of Gastroenterology, Affiliated Hospital of Nantong University , Nantong, China
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Immuno-Modulatory Role of Porins: Host Immune Responses, Signaling Mechanisms and Vaccine Potential. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 842:79-108. [DOI: 10.1007/978-3-319-11280-0_6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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10
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Sinha D, Ghosh AK, Mukherjee S, Biswas R, Biswas T. Antigenic relatedness defines Toll-like receptor 2 is crafted on ligand blueprint. Immunobiology 2014; 219:798-801. [PMID: 25044028 DOI: 10.1016/j.imbio.2014.06.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 05/23/2014] [Accepted: 06/30/2014] [Indexed: 11/18/2022]
Abstract
Toll-like receptors are located particularly on mammalian immune cells to recognize pathogen-associated molecules. Toll-like receptors are categorized on the basis of ligand specificity that includes Toll-like receptor 2 with affinity for bacterial porin, the major outer membrane protein. Here we show TLR2 antibody recognizes the monomer of porin, primarily a TLR2-ligand in Western blot, thus displaying relatedness of primary structures between the receptor and its ligand. Quantitative analysis revealed relatedness of the native porin molecule with TLR2 was as high as 71%, suggesting imprint of native porin trimer is mostly copied by the receptor crossing limits of primary structures. Flow cytometric analysis of TLR2 on HEK-293 cells shows the receptor and ligand also have common molecular patterns on surface, which is distinctively separate from regions assigned for putative TLR(*)ligand interaction. Molecular mimetic and specificity of TLR will caution investigators targeting TLR-ligands to develop adjuvants and vaccines.
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Affiliation(s)
- Debolina Sinha
- Division of Immunology, National Institute of Cholera and Enteric Diseases, Kolkata 700 010, India
| | - Amlan Kanti Ghosh
- Division of Immunology, National Institute of Cholera and Enteric Diseases, Kolkata 700 010, India
| | - Subhadeep Mukherjee
- Division of Immunology, National Institute of Cholera and Enteric Diseases, Kolkata 700 010, India
| | - Ratna Biswas
- Division of Immunology, National Institute of Cholera and Enteric Diseases, Kolkata 700 010, India
| | - Tapas Biswas
- Division of Immunology, National Institute of Cholera and Enteric Diseases, Kolkata 700 010, India.
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11
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Perez-Shibayama C, Gil-Cruz C, Pastelin-Palacios R, Cervantes-Barragan L, Hisaki E, Chai Q, Onder L, Scandella E, Regen T, Waisman A, Isibasi A, Lopez-Macias C, Ludewig B. IFN-γ-producing CD4+ T cells promote generation of protective germinal center-derived IgM+ B cell memory against Salmonella Typhi. THE JOURNAL OF IMMUNOLOGY 2014; 192:5192-200. [PMID: 24778443 DOI: 10.4049/jimmunol.1302526] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Abs play a significant role in protection against the intracellular bacterium Salmonella Typhi. In this article, we investigated how long-term protective IgM responses can be elicited by a S. Typhi outer-membrane protein C- and F-based subunit vaccine (porins). We found that repeated Ag exposure promoted a CD4(+) T cell-dependent germinal center reaction that generated mutated IgM-producing B cells and was accompanied by a strong expansion of IFN-γ-secreting T follicular helper cells. Genetic ablation of individual cytokine receptors revealed that both IFN-γ and IL-17 are required for optimal germinal center reactions and production of porin-specific memory IgM(+) B cells. However, more profound reduction of porin-specific IgM B cell responses in the absence of IFN-γR signaling indicated that this cytokine plays a dominant role. Importantly, mutated IgM mAbs against porins exhibited bactericidal capacity and efficiently augmented S. Typhi clearance. In conclusion, repeated vaccination with S. Typhi porins programs type I T follicular helper cell responses that contribute to the diversification of B cell memory and promote the generation of protective IgM Abs.
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Affiliation(s)
- Christian Perez-Shibayama
- Institute of Immunobiology, Kantonal Hospital St. Gallen, CH-9007 St. Gallen, Switzerland; Medical Research Unit on Immunochemistry, Specialties Hospital, National Medical Centre "Siglo XXI," Mexican Social Security Institute, Mexico City, C.P. 06020 Mexico
| | - Cristina Gil-Cruz
- Institute of Immunobiology, Kantonal Hospital St. Gallen, CH-9007 St. Gallen, Switzerland; Medical Research Unit on Immunochemistry, Specialties Hospital, National Medical Centre "Siglo XXI," Mexican Social Security Institute, Mexico City, C.P. 06020 Mexico
| | | | - Luisa Cervantes-Barragan
- Institute of Immunobiology, Kantonal Hospital St. Gallen, CH-9007 St. Gallen, Switzerland; Department of Pathology, Washington University School of Medicine, St. Louis, MO 63130; Department of Immunology, Washington University School of Medicine, St. Louis, MO 63130; and
| | - Emiliano Hisaki
- Medical Research Unit on Immunochemistry, Specialties Hospital, National Medical Centre "Siglo XXI," Mexican Social Security Institute, Mexico City, C.P. 06020 Mexico
| | - Qian Chai
- Institute of Immunobiology, Kantonal Hospital St. Gallen, CH-9007 St. Gallen, Switzerland
| | - Lucas Onder
- Institute of Immunobiology, Kantonal Hospital St. Gallen, CH-9007 St. Gallen, Switzerland
| | - Elke Scandella
- Institute of Immunobiology, Kantonal Hospital St. Gallen, CH-9007 St. Gallen, Switzerland
| | - Tommy Regen
- Institute for Molecular Medicine, University of Mainz, D-55131 Mainz, Germany
| | - Ari Waisman
- Institute for Molecular Medicine, University of Mainz, D-55131 Mainz, Germany
| | - Armando Isibasi
- Medical Research Unit on Immunochemistry, Specialties Hospital, National Medical Centre "Siglo XXI," Mexican Social Security Institute, Mexico City, C.P. 06020 Mexico
| | - Constantino Lopez-Macias
- Medical Research Unit on Immunochemistry, Specialties Hospital, National Medical Centre "Siglo XXI," Mexican Social Security Institute, Mexico City, C.P. 06020 Mexico
| | - Burkhard Ludewig
- Institute of Immunobiology, Kantonal Hospital St. Gallen, CH-9007 St. Gallen, Switzerland;
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12
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Immune Adjuvant Effect of Molecularly-defined Toll-Like Receptor Ligands. Vaccines (Basel) 2014; 2:323-53. [PMID: 26344622 PMCID: PMC4494261 DOI: 10.3390/vaccines2020323] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 03/27/2014] [Accepted: 03/28/2014] [Indexed: 01/07/2023] Open
Abstract
Vaccine efficacy is optimized by addition of immune adjuvants. However, although adjuvants have been used for over a century, to date, only few adjuvants are approved for human use, mostly aimed at improving vaccine efficacy and antigen-specific protective antibody production. The mechanism of action of immune adjuvants is diverse, depending on their chemical and molecular nature, ranging from non-specific effects (i.e., antigen depot at the immunization site) to specific activation of immune cells leading to improved host innate and adaptive responses. Although the detailed molecular mechanism of action of many adjuvants is still elusive, the discovery of Toll-like receptors (TLRs) has provided new critical information on immunostimulatory effect of numerous bacterial components that engage TLRs. These ligands have been shown to improve both the quality and the quantity of host adaptive immune responses when used in vaccine formulations targeted to infectious diseases and cancer that require both humoral and cell-mediated immunity. The potential of such TLR adjuvants in improving the design and the outcomes of several vaccines is continuously evolving, as new agonists are discovered and tested in experimental and clinical models of vaccination. In this review, a summary of the recent progress in development of TLR adjuvants is presented.
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13
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Crystallographic analysis of Neisseria meningitidis PorB extracellular loops potentially implicated in TLR2 recognition. J Struct Biol 2014; 185:440-7. [PMID: 24361688 PMCID: PMC3943661 DOI: 10.1016/j.jsb.2013.12.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 12/13/2013] [Accepted: 12/14/2013] [Indexed: 01/07/2023]
Abstract
Among all Neisseriae species, Neisseria meningitidis and Neisseria gonorrhoeae are the only human pathogens, causative agents of bacterial meningitis and gonorrhoea, respectively. PorB, a pan-Neisseriae trimeric porin that mediates diffusive transport of essential molecules across the bacterial outer membrane, is also known to activate host innate immunity via Toll-like receptor 2 (TLR2)-mediated signaling. The molecular mechanism of PorB binding to TLR2 is not known, but it has been hypothesized that electrostatic interactions contribute to ligand/receptor binding. Strain-specific sequence variability in the surface-exposed loops of PorB which are potentially implicated in TLR2 binding, may explain the difference in TLR2-mediated cell activation in vitro by PorB homologs from the commensal Neisseriae lactamica and the pathogen N. meningitidis. Here, we report a comparative structural analysis of PorB from N. meningitidis serogroup B strain 8765 (63% sequence homology with PorB from N. meningitidis serogroup W135) and a mutant in which amino acid substitutions in the extracellular loop 7 lead to significantly reduced TLR2-dependent activity in vitro. We observe that this mutation both alters the loop conformation and causes dramatic changes of electrostatic surface charge, both of which may affect TLR2 recognition and signaling.
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14
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In vivo and in vitro characterization of the immune stimulating activity of the Neisserial porin PorB. PLoS One 2013; 8:e82171. [PMID: 24349212 PMCID: PMC3859593 DOI: 10.1371/journal.pone.0082171] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Accepted: 10/30/2013] [Indexed: 12/22/2022] Open
Abstract
Vaccines play a vital role in modern medicine. The development of novel vaccines for emerging and resistant pathogens has been aided in recent years by the use of novel adjuvants in subunit vaccines. A deeper understanding of the molecular pathways behind adjuvanticity is required to better select immunostimulatory molecules for use in individual vaccines. To this end, we have undertaken a study of the essential signaling pathways involved in the innate and adaptive immune responses to the Neisseria meningitidis outer membrane protein Porin B (PorB). We have previously demonstrated that PorB is an agonist of Toll-Like Receptor 2 (TLR2) and acts as an adjuvant in vaccines for protein, carbohydrate and lipopolysaccharide antigens using murine models. Here we demonstrate NFκB translocation following stimulation with PorB only occurs in the presence of TLR2. IL-6 and TNF-α secretion was shown to be MAPK dependent. Surface expression of activation markers on macrophages, including CD40, CD69, and CD86, was increased following PorB stimulation in vitro. Interestingly, some upregulation of CD54 and CD69 was still observed in macrophages obtained from TLR2 KO mice, indicating a possible non-TLR2 mediated activation pathway induced by PorB. In a murine vaccination model, using ovalbumin as the antigen and PorB as the adjuvant, a decreased antigen-specific IgG production was observed in TLR2 KO mice; adjuvant-dependent increased IgG production was entirely ablated in MyD88 KO mice. These observations demonstrate the importance of the above pathways to the adjuvant activity of PorB. The potential TLR2 independent effect is currently being explored.
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The amino acid sequence of Neisseria lactamica PorB surface-exposed loops influences Toll-like receptor 2-dependent cell activation. Infect Immun 2012; 80:3417-28. [PMID: 22825445 DOI: 10.1128/iai.00683-12] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Toll-like receptors (TLRs) play a major role in host mucosal and systemic defense mechanisms by recognizing a diverse array of conserved pathogen-associated molecular patterns (PAMPs). TLR2, with TLR1 and TLR6, recognizes structurally diverse bacterial products such as lipidated factors (lipoproteins and peptidoglycans) and nonlipidated proteins, i.e., bacterial porins. PorB is a pan-neisserial porin expressed regardless of organisms' pathogenicity. However, commensal Neisseria lactamica organisms and purified N. lactamica PorB (published elsewhere as Nlac PorB) induce TLR2-dependent proinflammatory responses of lower magnitude than N. meningitidis organisms and N. meningitidis PorB (published elsewhere as Nme PorB). Both PorB types bind to TLR2 in vitro but with different apparent specificities. The structural and molecular details of PorB-TLR2 interaction are only beginning to be unraveled and may be due to electrostatic attraction. PorB molecules have significant strain-specific sequence variability within surface-exposed regions (loops) putatively involved in TLR2 interaction. By constructing chimeric recombinant PorB loop mutants in which surface-exposed loop residues have been switched between N. lactamica PorB and N. meningitidis PorB, we identified residues in loop 5 and loop 7 that influence TLR2-dependent cell activation using HEK cells and BEAS-2B cells. These loops are not uniquely responsible for PorB interaction with TLR2, but NF-κB and MAP kinases signaling downstream of TLR2 recognition are likely influenced by a hypothetical "TLR2-binding signature" within the sequence of PorB surface-exposed loops. Consistent with the effect of purified PorB in vitro, a chimeric N. meningitidis strain expressing N. lactamica PorB induces lower levels of interleukin 8 (IL-8) secretion than wild-type N. meningitidis, suggesting a role for PorB in induction of host cell activation by whole bacteria.
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The FomA porin from Fusobacterium nucleatum is a Toll-like receptor 2 agonist with immune adjuvant activity. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2012; 19:1093-101. [PMID: 22623652 DOI: 10.1128/cvi.00236-12] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Many bacterial components selectively activate immune and nonhematopoietic target cells via Toll-like receptor (TLR) signaling; modulation of such host responses defines the immune adjuvant properties of these bacterial products. For example, the outer membrane protein porins from Neisseria, Salmonella, and Shigella are known TLR2 agonists with established systemic and mucosal immune adjuvanticity. Early work indicated that the FomA porin from Fusobacterium nucleatum has immune adjuvant activity in mice. Using a purified recombinant FomA, we have verified its immune stimulatory properties and have defined a role for TLR2 signaling in its in vitro and in vivo activity. FomA induces interleukin 8 (IL-8) secretion and NF-κB-dependent luciferase activity in HEK cells expressing TLR2, IL-6 secretion, and cell surface upregulation of CD86 and major histocompatibility complex (MHC) II in primary B cells from wild-type mice, but it fails to activate cells from TLR2 knockout mice. Accordingly, the immune adjuvant activity of FomA is also TLR2 dependent. In a mouse model of immunization with ovalbumin (OVA), FomA induces enhanced production of OVA-specific IgM and IgG, including IgG1 and IgG2b antibodies, as well as enhanced secretion of IL-10 and IL-6, consistent with a Th2-type adjuvant effect. We also observe a moderate production of anti-FomA antibodies, suggesting that FomA is also immunogenic, a quality that is also TLR2 dependent. Therefore, modulation of host immune responses by FomA may be effective for targeting general host immunity not only to pathogens (as a novel TLR2 adjuvant) but also to F. nucleatum itself (as an antigen), expanding its use as a self-adjuvanted antigen in an immunization strategy against polymicrobial infections, including those by F. nucleatum.
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So NSY, Ostrowski MA, Gray-Owen SD. Vigorous response of human innate functioning IgM memory B cells upon infection by Neisseria gonorrhoeae. THE JOURNAL OF IMMUNOLOGY 2012; 188:4008-22. [PMID: 22427638 DOI: 10.4049/jimmunol.1100718] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Neisseria gonorrhoeae, the cause of the sexually transmitted infection gonorrhea, elicits low levels of specific Ig that decline rapidly after the bacteria are cleared. Reinfection with the same serovar can occur, and prior gonococcal infection does not alter the Ig response upon subsequent exposure, suggesting that protective immunity is not induced. The mucosal Ig response apparent during gonorrhea does not correlate with that observed systemically, leading to a suggestion that it is locally generated. In considering whether N. gonorrhoeae directly influences B cells, we observed that gonococcal infection prolonged viability of primary human B cells in vitro and elicited robust activation and vigorous proliferative responses in the absence of T cells. Furthermore, we observed the specific expansion of IgD(+)CD27(+) B cells in response to gonococcal infection. These cells are innate in function, conferring protection against diverse microbes by producing low-affinity, broadly reactive IgM without inducing classical immunologic memory. Although gonococcal infection of B cells produced small amounts of gonococcal-specific IgM, IgM specific for irrelevant Ags were also produced, suggesting a broad, polyspecific Ig response. The gonococci were effectively bound and engulfed by B cells. TLR9-inhibitory CpGs blocked B cell responses, indicating that intracellular bacterial degradation allows for innate immune detection within the phagolysosome. To our knowledge, this is the first report of a bacterial pathogen having specific affinity for the human IgM memory B cells, driving their potent activation and polyclonal Ig response. This unfocused T-independent response explains the localized Ig response that occurs, despite an absence of immunologic memory elicited during gonorrhea.
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Affiliation(s)
- Nancy S Y So
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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Cruz SC, Souza SL, Cruz AC, Silva GP, Milagres LG. Human antibody and memory B and T-cell responses after primary and booster immunisation against Neisseria meningitidis B. Vaccine 2011; 29:7387-94. [DOI: 10.1016/j.vaccine.2011.07.072] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Revised: 07/15/2011] [Accepted: 07/17/2011] [Indexed: 12/20/2022]
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Outer membrane protein complex of Meningococcus enhances the antipolysaccharide antibody response to pneumococcal polysaccharide-CRM₁₉₇ conjugate vaccine. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2011; 18:724-9. [PMID: 21450979 DOI: 10.1128/cvi.00053-11] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Bacterial polysaccharides (PS) are T cell-independent antigens that do not induce immunologic memory and are poor immunogens in infants. Conjugate vaccines in which the PS is covalently linked to a carrier protein have enhanced immunogenicity that resembles that of T cell-dependent antigens. The Haemophilus influenzae type b (Hib) conjugate vaccine, which uses the outer membrane protein complex (OMPC) from meningococcus as a carrier protein, elicits protective levels of anti-capsular PS antibody (Ab) after a single dose, in contrast to other conjugate vaccines, which require multiple doses. We have previously shown that OMPC robustly engages Toll-like receptor 2 (TLR2) and enhances the early anti-Hib PS Ab titer associated with an increase in TLR2-mediated induction of cytokines. We now show that the addition of OMPC to the 7-valent pneumococcal PS-CRM₁₉₇ conjugate vaccine during immunization significantly increases the anti-PS IgG and IgM responses to most serotypes of pneumococcus contained in the vaccine. The addition of OMPC also increased the likelihood of anti-PS IgG3 production against serotypes 4, 6B, 9V, 18C, 19F, and 23F. Splenocytes from mice who had received OMPC with the pneumococcal conjugate vaccine produced significantly more interleukin-2 (IL-2), IL-4, IL-6, IL-10, tumor necrosis factor alpha (TNF-α), and gamma interferon (IFN-γ) than splenocytes from mice who received phosphate-buffered saline (PBS) plus the conjugate vaccine. We conclude that OMPC enhances the anti-PS Ab response to pneumococcal PS-CRM₁₉₇ conjugate vaccine, an effect associated with a distinct change in cytokine profile. It may be possible to reduce the number of conjugate vaccine doses required to achieve protective Ab levels by priming with adjuvants that are TLR2 ligands.
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Vaughan AT, Brackenbury LS, Massari P, Davenport V, Gorringe A, Heyderman RS, Williams NA. Neisseria lactamicaSelectively Induces Mitogenic Proliferation of the Naive B Cell Pool via Cell Surface Ig. THE JOURNAL OF IMMUNOLOGY 2010; 185:3652-60. [DOI: 10.4049/jimmunol.0902468] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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21
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Wetzler LM. Innate immune function of the neisserial porins and the relationship to vaccine adjuvant activity. Future Microbiol 2010; 5:749-58. [PMID: 20441547 DOI: 10.2217/fmb.10.41] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Neisseria meningitidis is a Gram-negative pathogenic bacteria responsible for bacterial meningitis and septicemia. Porins are the most represented outer membrane proteins in the pathogenic Neisseria species, functioning as pores for the exchange of ions, and are characterized by a trimeric beta-barrel structure. Neisserial porins have been shown to act as adjuvants in the immune response via activation of B cells and other antigen-presenting cells. Their effect on the immune response is mediated by upregulation of the costimulatory molecule B7-2 (CD86) on the surface of antigen-presenting cells, an effect that is dependent on Toll-like receptor (TLR)2 and MyD88, through a cascade of signal transduction events mediated by direct binding of the porin to the TLR2-TLR1 heterodimer. This article summarizes work carried out investigating the mechanisms of the immune stimulating capacity of the neisserial porins (specifically meningococcal PorB), emphasizing cellular events involved in antigen-presenting cell activation and induction of expression of cell surface molecules involved in the immune response.
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Affiliation(s)
- Lee M Wetzler
- Boston University School of Medicine, Boston, MA, USA.
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Vaughan AT, Gorringe A, Davenport V, Williams NA, Heyderman RS. Absence of mucosal immunity in the human upper respiratory tract to the commensal bacteria Neisseria lactamica but not pathogenic Neisseria meningitidis during the peak age of nasopharyngeal carriage. THE JOURNAL OF IMMUNOLOGY 2009; 182:2231-40. [PMID: 19201877 DOI: 10.4049/jimmunol.0802531] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The normal flora that colonizes the mucosal epithelia has evolved diverse strategies to evade, modulate, or suppress the immune system and avoid clearance. Neisseria lactamica and Neisseria meningitidis are closely related obligate inhabitants of the human upper respiratory tract. N. lactamica is a commensal but N. meningitidis is an opportunistic pathogen that occasionally causes invasive disease such as meningitis and septicemia. We demonstrate that unlike N. meningitidis, N. lactamica does not prime the development of mucosal T or B cell memory during the peak period of colonization. This cannot be explained by the induction of peripheral tolerance or regulatory CD4(+)CD25(+) T cell activity. Instead, N. lactamica mediates a B cell-dependent mitogenic proliferative response that is absent to N. meningitidis. This mitogenic response is associated with the production of T cell-independent polyclonal IgM that we propose functions by shielding colonizing N. lactamica from the adaptive immune system, maintaining immunological ignorance in the host. We conclude that, in contrast to N. meningitidis, N. lactamica maintains a commensal relationship with the host in the absence of an adaptive immune response. This may prolong the period of susceptibility to colonization by both pathogenic and nonpathogenic Neisseria species.
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Affiliation(s)
- Andrew T Vaughan
- Department of Cellular and Molecular Medicine, School of Medical Science, University of Bristol, Bristol, United Kingdom.
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Durand V, MacKenzie J, de Leon J, Mesa C, Quesniaux V, Montoya M, Le Bon A, Wong SY. Role of lipopolysaccharide in the induction of type I interferon-dependent cross-priming and IL-10 production in mice by meningococcal outer membrane vesicles. Vaccine 2009; 27:1912-22. [DOI: 10.1016/j.vaccine.2009.01.109] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Revised: 01/17/2009] [Accepted: 01/22/2009] [Indexed: 02/06/2023]
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Fu TM, Grimm KM, Citron MP, Freed DC, Fan J, Keller PM, Shiver JW, Liang X, Joyce JG. Comparative immunogenicity evaluations of influenza A virus M2 peptide as recombinant virus like particle or conjugate vaccines in mice and monkeys. Vaccine 2009; 27:1440-7. [PMID: 19146898 DOI: 10.1016/j.vaccine.2008.12.034] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2008] [Revised: 12/02/2008] [Accepted: 12/20/2008] [Indexed: 11/16/2022]
Abstract
Immunization against M2 peptide, also called M2e, from influenza A virus is an innovative vaccine approach for induction of cross-strain protective immunity. Two promising M2 vaccine compositions reported to date are M2 peptide chemically conjugated to carrier proteins or M2 peptide recombinantly expressed on the surface of virus like particles (VLPs) of hepatitis B virus core antigen (HBVc). To conduct a head-to-head comparison of these approaches, we constructed two recombinant HBVc VLPs expressing M2 peptide and prepared two conjugate vaccines with M2 peptide chemically coupled to Neisseria meningitidis outer membrane complex (OMPC) or HBVc VLP, respectively. Here, we showed superior immunogenicity of M2 peptide conjugated to OMPC and M2 peptide expressed on the surface of HBVc antigen based on dose-titration responses in mice. Surprisingly, HBVc expressing M2 peptide was an inferior vaccine in rhesus monkeys, whether as a primary vaccine or as a booster vaccine, when compared with M2-OMPC conjugate vaccine.
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Affiliation(s)
- Tong-Ming Fu
- Department of Vaccine Basic Research, Merck Research Laboratories, West Point, PA 19486, United States.
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Banerjee P, Biswas A, Biswas T. Porin-incorporated liposome induces Toll-like receptors 2- and 6-dependent maturation and type 1 response of dendritic cell. Int Immunol 2008; 20:1551-63. [DOI: 10.1093/intimm/dxn114] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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Reiser H, Wang J, Chong L, Watkins WJ, Ray AS, Shibata R, Birkus G, Cihlar T, Wu S, Li B, Liu X, Henne IN, Wolfgang GH, Desai M, Rhodes GR, Fridland A, Lee WA, Plunkett W, Vail D, Thamm DH, Jeraj R, Tumas DB. GS-9219—A Novel Acyclic Nucleotide Analogue with Potent Antineoplastic Activity in Dogs with Spontaneous Non–Hodgkin's Lymphoma. Clin Cancer Res 2008; 14:2824-32. [DOI: 10.1158/1078-0432.ccr-07-2061] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Role of protein tyrosine kinase and Erk1/2 activities in the Toll-like receptor 2-induced cellular activation of murine B cells by neisserial porin. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2008; 15:630-7. [PMID: 18287580 DOI: 10.1128/cvi.00435-07] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Neisserial porins are potent immune adjuvants and have been demonstrated to stimulate and induce the activation of human and murine B lymphocytes. Their immunopotentiating ability is due largely to the upregulation of the surface expression of the costimulatory ligand CD86 (B7-2) on B cells and other antigen-presenting cells. Porin-induced activation is dependent on the innate immune pattern recognition receptor Toll-like receptor 2 (TLR2). These data have led us to investigate the signal transduction events induced by PorB from Neisseria meningitidis and then, using inhibitors of these pathways, to establish the mechanism by which this bacterial major outer membrane protein induces CD86 upregulation and the proliferation of murine B cells. PorB was able to induce (i) protein tyrosine kinase (PTK) activity, (ii) the phosphorylation of Erk1 and Erk2, and (iii) IkappaB-alpha phosphorylation, leading to NF-kappaB nuclear translocation in B cells in a TLR2-dependent manner. PorB-induced NF-kappaB nuclear translocation was not dependent on either PTK or Erk1/2 activities. However, B-cell proliferation and the induction of increased surface expression of CD86 by PorB were dependent on PTK activity and not Erk1/2 activation. In conclusion, PorB acts through TLR2 as a B-cell mitogen, triggering tyrosine phosphorylation of various cellular proteins that are involved in proliferation and CD86 expression, as well as the phosphorylation of Erk1/2, which is not necessary for CD86 upregulation or the proliferation of B cells.
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Biswas A, Banerjee P, Biswas T. Priming of CD4+ T cells with porin of Shigella dysenteriae activates the cells toward type 1 polarization. Int Immunol 2008; 20:81-88. [DOI: 10.1093/intimm/dxm122] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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The PorB porin from commensal Neisseria lactamica induces Th1 and Th2 immune responses to ovalbumin in mice and is a potential immune adjuvant. Vaccine 2007; 26:786-96. [PMID: 18191311 DOI: 10.1016/j.vaccine.2007.11.080] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Revised: 11/27/2007] [Accepted: 11/29/2007] [Indexed: 12/20/2022]
Abstract
Porins from pathogenic Neisseriae are among several bacterial products with immune adjuvant activity. Neisseria meningitidis (Nme) PorB, has been shown to induce immune cells activation in a TLR2-dependent manner and acts as a vaccine immune adjuvant. The PorB porin from Neisseria lactamica (Nlac), a common nasopharyngeal commensal, shares significant structural and functional similarities with Nme PorB. In this work we ask whether the immune adjuvant ability of porins from pathogenic Neisserial strains is a characteristic shared with porins from non-pathogenic Neisserial species or whether it is unique for bacterial products derived from microorganisms capable of inducing inflammation and disease. We evaluated the potential immune adjuvant effect of Nlac PorB in mice using ovalbumin (OVA) as a prototype antigen. Immunization with Nlac PorB/OVA induced high OVA-specific IgG and IgM titers compared to OVA alone, similar to other adjuvants such as Nme PorB and alum. High titers of IgG1 and IgG2b were detected as well as production of IL-4, IL-10, IL-12 and INF-gamma in response to Nlac PorB, consistent with induction of both a Th1-type and a Th2-type immune response. OVA-specific proliferation was also determined in splenocytes from Nlac PorB/OVA-immunized mice. In addition, B cell activation in vitro and cytokine production in response to Nlac PorB was found to be mediated by TLR2, in a similar manner to Nme PorB.
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Burke JM, Ganley-Leal LM, Khatri A, Wetzler LM. Neisseria meningitidis PorB, a TLR2 ligand, induces an antigen-specific eosinophil recall response: potential adjuvant for helminth vaccines? THE JOURNAL OF IMMUNOLOGY 2007; 179:3222-30. [PMID: 17709538 DOI: 10.4049/jimmunol.179.5.3222] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Efficacious adjuvants are important components of new vaccines. The neisserial outer membrane protein, PorB, is a TLR2 ligand with unique adjuvant activity. We demonstrate that PorB promotes Th2-skewed cellular immune response to the model Ag, OVA, in mice, including Ag-specific recall eosinophil recruitment to the peritoneum. PorB induces chemokine secretion by myeloid cells using both TLR2-dependent and -independent mechanisms, suggesting that anatomical distribution of TLR2(+) cells may not be a limiting factor for potential vaccine strategies. The results from this study suggest that PorB, and other TLR2 ligands, may be ideal for use against pathogens where eosinophilia may be protective, such as parasitic helminths.
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Affiliation(s)
- Jennifer M Burke
- Department of Pathology, Boston University School of Medicine, Boston, MA 02118, USA
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31
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van Berkel MEAT, Schrijver EHR, van Mourik A, Tesselaar K, van der Ley P, Steeghs L, Oosterwegel MA. A critical contribution of both CD28 and ICOS in the adjuvant activity of Neisseria meningitidis H44/76 LPS and lpxL1 LPS. Vaccine 2007; 25:4681-8. [PMID: 17499399 DOI: 10.1016/j.vaccine.2007.04.016] [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] [Received: 11/28/2006] [Revised: 03/27/2007] [Accepted: 04/07/2007] [Indexed: 11/16/2022]
Abstract
The development of novel vaccines against Neisseria meningitidis recently gained momentum by the generation of penta-acylated lpxL1 LPS which has similar adjuvant activity, but reduced endotoxic activity as compared to hexa-acylated wild type (H44/76) LPS. We investigated the costimulation requirements for the adjuvant activity of both forms of LPS by immunizing CD28-, ICOS- and B7.1/2/ICOS-deficient mice. Both ICOS and CD28 appeared essential for optimal adjuvant activity of H44/76 LPS or lpxL1 LPS. Interestingly, ICOS-mediated costimulation predominates in the adjuvant activity of lpxL1 LPS, while both ICOS and CD28 are required for H44/76 LPS adjuvant activity.
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MESH Headings
- Adjuvants, Immunologic
- Animals
- Antibodies, Bacterial/blood
- Antigens, Differentiation, T-Lymphocyte/genetics
- Antigens, Differentiation, T-Lymphocyte/immunology
- Bacterial Outer Membrane Proteins/immunology
- CD28 Antigens/genetics
- CD28 Antigens/immunology
- Enzyme-Linked Immunosorbent Assay
- Immunoglobulin G/blood
- Inducible T-Cell Co-Stimulator Protein
- Lipopolysaccharides/chemistry
- Lipopolysaccharides/immunology
- Meningococcal Vaccines/immunology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Models, Animal
- Molecular Structure
- Neisseria meningitidis/immunology
- Polysaccharides, Bacterial/chemistry
- Polysaccharides, Bacterial/pharmacology
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Schnitzler AC, Burke JM, Wetzler LM. Induction of cell signaling events by the cholera toxin B subunit in antigen-presenting cells. Infect Immun 2007; 75:3150-9. [PMID: 17353279 PMCID: PMC1932910 DOI: 10.1128/iai.00581-06] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cholera toxin (CT) is one of the most effective and widely studied mucosal adjuvants. Although the ADP-ribosylating A subunit has been implicated in augmenting immune responses, the receptor-binding B subunit (CT-B) has greater immunogenicity and may be a repository of adjuvant activity without potential toxicity. In order to elucidate mechanisms of immune modulation by CT-B alone, primary B cells and macrophages were assessed for responses to CT-B in vitro, as measured by the expression of cell surface markers, cellular signaling events, and cytokine secretion. Increased phosphorylation of multiple signaling molecules, including Erk1/2 and p38, was detected. CT-B also induced transactivation of the transcription elements cyclic AMP-responsive element and NF-kappaB, the latter of which was inhibited by phosphotyrosine inhibition. While specific inhibition of MEK1/2 did not reduce CT-B induction of cell surface marker expression, it did attenuate CT-B-mediated interleukin-6 secretion. These data show that CT-B induces a set of signaling events related to cellular activation, surface molecule expression, and cytokine production that has potential implications for elucidating CT-B adjuvant activity in the absence of enzymatically active holotoxin.
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Affiliation(s)
- Aletta C Schnitzler
- Evans Biomedical Research Center, Boston University School of Medicine, 650 Albany Street, Boston, MA 02118, USA
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Mansour MK, Latz E, Levitz SM. Cryptococcus neoformans glycoantigens are captured by multiple lectin receptors and presented by dendritic cells. THE JOURNAL OF IMMUNOLOGY 2006; 176:3053-61. [PMID: 16493064 DOI: 10.4049/jimmunol.176.5.3053] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Cell-mediated immune responses to glycoantigens have been largely uncharacterized. Protective T cell responses to the pathogenic yeast Cryptococcus neoformans are dependent on heavily mannosylated Ags termed mannoproteins. In the work presented, the innate immune response to mannoprotein was determined. Purified murine splenic dendritic cells (DC), B cells, and macrophages were used to stimulate mannoprotein-specific T cells. Only DC were capable of any measurable stimulation. Depletion of DC resulted in the abrogation of the T cell response. Human and murine DC rapidly captured fluorescent-labeled mannoprotein by a mannose receptor-mediated process. Using transfected cell lines, the type II C-type lectin receptor DC-specific ICAM-3-grabbing nonintegrin (CD209) was determined to have affinity for mannoprotein. Taken together with prior work demonstrating that mannoprotein was captured by the macrophage mannose receptor (CD206), these data suggest that multiple mannose receptors on DC recognize mannoprotein. Pulsing experiments demonstrated that DC captured sufficient mannoprotein over 2 h to account for 50% of total stimulation. Capture appeared dependent on mannose receptors, as competitive mannosylated inhibitors and calcium chelators each interfered with T cell stimulation. By confocal microscopy, intracellular mannoprotein trafficked to an endo-lysosomal compartment in DC, and at later time points extended into tubules in a similar fashion to the degradation marker DQ-OVA. Mannoprotein colocalized intracellularly with CD206 and CD209. These data suggest that DC provide the crucial link between innate and adaptive immune responses to C. neoformans via a process that is dependent upon the efficient uptake of mannoprotein by mannose receptors.
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Affiliation(s)
- Michael K Mansour
- Department of Microbiology and Immunology Training Program, Boston University School of Medicine, Boston, MA 02118, USA
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Massari P, Visintin A, Gunawardana J, Halmen KA, King CA, Golenbock DT, Wetzler LM. Meningococcal porin PorB binds to TLR2 and requires TLR1 for signaling. THE JOURNAL OF IMMUNOLOGY 2006; 176:2373-80. [PMID: 16455995 DOI: 10.4049/jimmunol.176.4.2373] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
TLR2 plays a key role in the initiation of the cellular innate immune responses by a wide range of bacterial products. TLRs signaling, including TLR2 and its coreceptors TLR1 and TLR6, is mediated by a number of specific ligands. Although many of the TLR-mediated cell signaling pathways have been elucidated in the past few years, the molecular mechanisms that lead to cell activation are still poorly understood. In this study, we investigate the interaction of PorB from Neisseria meningitidis with TLR2 and describe the direct binding of a bacterial protein to TLR2 for the first time. Using labeled PorB, we demonstrate its binding to TLR2 both in its soluble form in vitro, and when it is over-expressed on the surface of human embryonic kidney 293 cells. We also show that TLR2-mediated binding of PorB is directly related to cellular activation. In addition, using 293 cells expressing the chimeric TLR2/TLR1 and TLR2/TLR6 complexes, we report the selectivity of PorB binding to the TLR2/TLR1 heterodimer, which is required for initiating signaling in transfected 293 cells and in murine B cells. Together, these data provide new evidence that TLR2 recognizes PorB through direct binding, and that PorB-induced cell activation is mediated by a TLR2/TLR1 complex.
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Affiliation(s)
- Paola Massari
- Evans BioMedical Research Center, Division of Infectious Diseases, Department of Medicine, Boston University School of Medicine, MA 02118, USA.
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35
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Secundino I, López-Macías C, Cervantes-Barragán L, Gil-Cruz C, Ríos-Sarabia N, Pastelin-Palacios R, Angel Villasis-Keever M, Becker I, Luis Puente J, Calva E, Isibasi A. Salmonella porins induce a sustained, lifelong specific bactericidal antibody memory response. Immunology 2006; 117:59-70. [PMID: 16423041 PMCID: PMC1782194 DOI: 10.1111/j.1365-2567.2005.02263.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
We examined the ability of porins from Salmonella enterica serovar typhi to induce a long-term antibody response in BALB/c mice. These porins triggered a strong lifelong production of immunoglobulin G (IgG) antibody in the absence of exogenous adjuvant. Analysis of the IgG subclasses produced during this antibody response revealed the presence of the subclasses IgG2b, IgG1, IgG2a and weak IgG3. Despite the high homology of porins, the long-lasting anti-S. typhi porin sera did not cross-react with S. typhimurium. Notably, the antiporin sera showed a sustained lifelong bactericidal-binding activity to the wild-type S. typhi strain, whereas porin-specific antibody titres measured by enzyme-linked immunosorbent assay (ELISA) decreased with time. Because our porin preparations contained the outer membrane proteins C and F (OmpC and OmpF), we evaluated the individual contribution of each porin to the long-lasting antibody response. OmpC and OmpF induced long-lasting antibody titres, measured by ELISA, which were sustained for 300 days. In contrast, although OmpC induced sustained high bactericidal antibody titres for 300 days, postimmunization, the bactericidal antibody titre induced by OmpF was not detected at day 180. These results indicate that OmpC is the main protein responsible for the antibody-mediated memory bactericidal response induced by porins. Taken together, our results show that porins are strong immunogens that confer lifelong specific bactericidal antibody responses in the absence of added adjuvant.
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Affiliation(s)
- Ismael Secundino
- Unidad de Investigación Médica en Inmunoquímica, Hospital de Especialidades del Centro Médico Nacional (CMN) Siglo XXI, Instituto Mexicano del Seguro Social (IMSS)México
| | - Constantino López-Macías
- Unidad de Investigación Médica en Inmunoquímica, Hospital de Especialidades del Centro Médico Nacional (CMN) Siglo XXI, Instituto Mexicano del Seguro Social (IMSS)México
| | - Luisa Cervantes-Barragán
- Unidad de Investigación Médica en Inmunoquímica, Hospital de Especialidades del Centro Médico Nacional (CMN) Siglo XXI, Instituto Mexicano del Seguro Social (IMSS)México
| | - Cristina Gil-Cruz
- Unidad de Investigación Médica en Inmunoquímica, Hospital de Especialidades del Centro Médico Nacional (CMN) Siglo XXI, Instituto Mexicano del Seguro Social (IMSS)México
| | - Nora Ríos-Sarabia
- Unidad de Investigación Médica en Inmunoquímica, Hospital de Especialidades del Centro Médico Nacional (CMN) Siglo XXI, Instituto Mexicano del Seguro Social (IMSS)México
| | | | | | - Ingeborg Becker
- Departmento de Medicina Experimental, Facultad de Medicina, UNAMMéxico
| | - José Luis Puente
- Departamento de Microbiología Molecular, Instituto de Biotecnología, UNAMCuernavaca, Morelos, México
| | - Edmundo Calva
- Departamento de Microbiología Molecular, Instituto de Biotecnología, UNAMCuernavaca, Morelos, México
| | - Armando Isibasi
- Unidad de Investigación Médica en Inmunoquímica, Hospital de Especialidades del Centro Médico Nacional (CMN) Siglo XXI, Instituto Mexicano del Seguro Social (IMSS)México
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36
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Massari P, King CA, MacLeod H, Wetzler LM. Improved purification of native meningococcal porin PorB and studies on its structure/function. Protein Expr Purif 2005; 44:136-46. [PMID: 16027004 DOI: 10.1016/j.pep.2005.04.021] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2005] [Revised: 04/26/2005] [Accepted: 04/29/2005] [Indexed: 11/30/2022]
Abstract
The outer membrane protein PorB of Neisseria meningitidis is a pore-forming protein which has various effects on eukaryotic cells. It has been shown to (1) up-regulate the surface expression of the co-stimulatory molecule CD86 and of MHC class II (which are TLR2/MyD88 dependent and related to the porin's immune-potentiating ability), (2) be involved in prevention of apoptosis by modulating the mitochondrial membrane potential, and (3) form pores in eukaryotic cells. As an outer membrane protein, its native trimeric form isolation is complicated by its insoluble nature, requiring the presence of detergent throughout the whole procedure, and by its tight association with other outer membrane components, such as neisserial LOS or lipoproteins. In this study, an improved chromatographic purification method to obtain an homogeneous product free of endotoxin and lipoprotein is described, without loss of any of the above-mentioned properties of the porin. Furthermore, we have investigated the requirement of the native trimeric structure for the porin's activity. Inactivation of functional PorB trimers into non-functional monomers was achieved by incubation on ice. Thus, routine long- and medium-term storage at low temperature may be a cause of porin inactivation.
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Affiliation(s)
- Paola Massari
- Evans BioMedical Research Center, Division of Infectious Diseases, Department of Medicine, Boston University School of Medicine, Boston Medical Center, Boston, MA, USA
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37
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Singleton TE, Massari P, Wetzler LM. Neisserial porin-induced dendritic cell activation is MyD88 and TLR2 dependent. THE JOURNAL OF IMMUNOLOGY 2005; 174:3545-50. [PMID: 15749891 DOI: 10.4049/jimmunol.174.6.3545] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Neisserial porins have been shown to act as B cell mitogens and immune adjuvants. PorA and PorB are the major outer membrane porin proteins of the human pathogen Neisseria meningitidis. We have shown that the mechanism of the immunopotentiating capability of porin involves up-regulation of the T cell costimulatory ligand, CD86. Due to neisserial porin's ability to activate B cells and potentiate immune responses, we hypothesized that porin also employs the potent immune stimulatory function of dendritic cells (DC). We examined the ability of purified N. meningitidis PorB to induce maturation of murine splenic and bone marrow-derived DC. PorB treatment induced DC maturation, as demonstrated by increased expression of CD86 and class I and II MHC molecules. In addition, PorB not only enhanced the allostimulatory activity of DC, but also augmented the ability of DC to stimulate T cells in an Ag-specific manner. PorB-matured DC secreted the inflammatory cytokine IL-6, which may have implications for the adjuvant property of porin. Induction of IL-6 by PorB is also significant because IL-6 is one of a number of cytokines produced during infection with N. meningitidis and may be involved in the inflammatory process observed during infection and disease. We previously demonstrated the requirement of MyD88 and TLR2 for PorB-induced B cell activation. In the present study, MyD88 and TLR2 were also essential for PorB-induced DC activation. This work is significant for elucidating the mechanism(s) of neisserial porin's immune stimulatory activity.
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MESH Headings
- Adaptor Proteins, Signal Transducing
- Animals
- Antigens, CD/metabolism
- Antigens, Differentiation/genetics
- Antigens, Differentiation/metabolism
- B7-2 Antigen
- Dendritic Cells/drug effects
- Dendritic Cells/immunology
- Female
- Histocompatibility Antigens Class II/metabolism
- Humans
- Immunologic Factors/pharmacology
- Interleukin-6/biosynthesis
- Lymphocyte Activation
- Male
- Membrane Glycoproteins/metabolism
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Myeloid Differentiation Factor 88
- Neisseria meningitidis/immunology
- Neisseria meningitidis/pathogenicity
- Porins/pharmacology
- Receptors, Cell Surface/deficiency
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/metabolism
- Receptors, Immunologic/deficiency
- Receptors, Immunologic/genetics
- Receptors, Immunologic/metabolism
- T-Lymphocytes/immunology
- Toll-Like Receptor 2
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Affiliation(s)
- Theresa E Singleton
- Department of Microbiology, Division of Graduate Medical Sciences, Boston University School of Medicine, Boston, MA 02118, USA
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38
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Fusco PC, Blake MS, Michon F. Meningococcal vaccine development: a novel approach. Expert Opin Investig Drugs 2005; 7:245-52. [PMID: 15991955 DOI: 10.1517/13543784.7.2.245] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Neisseria meningitidis is a major world-wide cause of meningitis. Effective capsular polysaccharide (CPS) vaccines that elicit CPS-specific bactericidal (BC) antibodies were previously developed and licensed to protect against meningococcal disease. However, due to their T-cell independent character, CPS vaccines are useless in infants and do not provide immunological memory or long-lasting protection in adults. CPS-protein conjugate vaccines are being developed to improve and broaden vaccine efficacy by creating T-cell dependent antigens. However, group B meningococci (GBM) are responsible for nearly half of meningococcal disease and possess a CPS, composed of polysialic acid, that is poorly immunogenic. N-propionyl (NPr) modification of the GBM polysaccharide (GBMP) has enhanced its immunogenicity, but BC antibodies are not induced at high levels, even when conjugated to conventional protein carriers, unless adjuvants stronger than aluminium hydroxide are used. We have chosen to couple the NPr-GBMP by reductive amination to a recombinant GBM class 3 porin (rPorB), which we have shown to modulate the immune response in animals towards the production of CPS-specific BC antibodies. We have also combined this conjugate with similar CPS-rPorB conjugates for groups A and C meningococci to form a trivalent A/B/C conjugate vaccine. This trivalent meningococcal vaccine has been shown to be safe and highly immunogenic in mice and non human primates, generating CPS-specific BC antibodies for each of the 3 major serogroups, which should provide world-wide protection against meningococcal disease.
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Affiliation(s)
- P C Fusco
- North American Vaccine, Inc., 12103 Indian Creek Court Beltsville, MD 20705, USA
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39
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Ray A, Biswas T. Porin of Shigella dysenteriae enhances Toll-like receptors 2 and 6 of mouse peritoneal B-2 cells and induces the expression of immunoglobulin M, immunoglobulin G2a and immunoglobulin A. Immunology 2005; 114:94-100. [PMID: 15606799 PMCID: PMC1782058 DOI: 10.1111/j.1365-2567.2004.02002.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Porin of Shigella dysenteriae type 1 increased the mRNA levels for Toll-like receptors TLR2 and TLR6, by 1.8-fold and twofold, respectively, in peritoneal cavity B-2 cells from C57BL/6 mice, implicating that the co-expression of TLR2 and TLR6 occurs as a combinatorial repertoire in response to porin. Among the two key TLRs, TLR2 and TLR4, which are primarily responsible for recognizing the majority of bacterial products, TLR2 alone participates in porin recognition. TLR2 expression was increased on B-2 cells, whereas the expression of TLR4 remained unaffected. Besides TLRs, mRNA for myeloid differentiation factor 88 (MyD88), an effector molecule associated with the TLR-mediated response, was enhanced by twofold, suggesting its involvement in the activity of porin. The B-2 cells showed a 1.8-fold increase in mRNA expression of the signalling molecule, nuclear factor-kappa B (NF-kappaB), in the presence of porin. Porin treatment of B-2 cells selectively up-regulated the expression of the costimulatory molecule, CD86, by 4.4-fold. Porin induced the cell-surface expression of immunoglobulin (Ig)M, of IgG2a preferentially among the IgG subclasses, and of IgA, on B-2 cells. The porin-mediated inductions of IgG2a and IgA were augmented by interleukin-6 on B-2 cells, by 2.7- and 1.6-fold, respectively.
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Affiliation(s)
- Avijit Ray
- Division of Immunology and Vaccine Development, National Institute of Cholera and Enteric Diseases, Kolkata-700 010, West Bengal, India
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40
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Ray A, Karmakar P, Biswas T. Up-regulation of CD80-CD86 and IgA on mouse peritoneal B-1 cells by porin of Shigella dysenteriae is Toll-like receptors 2 and 6 dependent. Mol Immunol 2005; 41:1167-75. [PMID: 15482852 DOI: 10.1016/j.molimm.2004.06.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2004] [Indexed: 12/12/2022]
Abstract
Porin of Shigella dysenteriae type 1 increased the mRNA levels for Toll-like receptor (TLR) 2 and TLR6 by 1.5- and 2.9-fold respectively, of peritoneal cavity B-1a and B-1b cells, implicating that coexpression of TLR2 and TLR6 is essential as a combinatorial repertoire for recognition of porin by the B-1 cells. Among the two key TLRs, TLR2 and TLR4, which are primarily responsible for recognizing majority of the bacterial products, TLR2 and not TLR4, participates in porin recognition. TLR2 got increased on both the B-1 cell populations whereas the TLR4 expression remained unaffected. Besides TLRs, mRNA for MyD88, an effector molecule associated with TLR-mediated response was enhanced by 1.8-fold that suggests of its involvement in the activity of porin. Both of the B-1 cell populations expressed strongly the mRNA for NF-kappaB in the presence of porin, that was 2.4-fold more than untreated control, conforming to the earlier finding that coexpression of TLR2 and TLR6, resulted in robust NF-kappaB activation for signaling. Porin treatment of B-1 cell populations of C57BL/6 mice, and C3H/HeJ mice in particular, selectively up-regulated the expression of the costimulatory molecules. CD80 expression got enhanced on the B-1a cells whereas CD86 got solely expressed on B-1b cells. Porin-induced cell surface expression of IgM and IgA on B-1 cell populations from C57BL/6 mice. The IgA-generating capacity, hallmark of mucosal immune response, was confirmed with B-1 cells of C3H/HeJ, the lipopolysaccharide non-responder mouse, in response to the protein. The porin-mediated induction of IgA was augmented by interleukin-6 on B-1a and B-1b cells, by 2.4- and 2.6-fold, respectively. The IgA expressed on both B-1a and B-1b cell surfaces after 72 h of culture was found to bind to the 38 kDa monomer of porin confirming it to be anti-porin IgA antibody.
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Affiliation(s)
- Avijit Ray
- Division of Immunology and Vaccine Development, National Institute of Cholera and Enteric Diseases, P-33, C.I.T. Road, Scheme XM, Kolkata 700010, West Bengal, India
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41
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Fukasawa LO, Dias WO, Schenkman RPF, Raw I, Tanizaki MM. Adjuvant can improve protection induced by OMV vaccine against Neisseria meningitidis serogroups B/C in neonatal mice. ACTA ACUST UNITED AC 2004; 41:205-10. [PMID: 15196569 DOI: 10.1016/j.femsim.2004.03.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2003] [Revised: 02/12/2004] [Accepted: 03/09/2004] [Indexed: 10/26/2022]
Abstract
Meningococcal outer membrane vesicle (OMV) vaccines are weak antigens in infants. This study aimed at investigating alternative adjuvants for induction of functional antibodies in newborn mice. Serogroup B/C anti-meningococcal vaccines, consisting of capsular polysaccharide from serogroup C (PSC) conjugated to OMV from one serogroup B serosubtype prevalent in Brazil, combined with OMV from another prevalent serosubtype, were tested in newborn and adult mice with the following adjuvants: aluminum hydroxide, MPL (monophosphoryl lipid A), Titermax and MF59. Total IgG, IgG avidity index determination and bactericidal assay were performed with sera from immunized mice. Antibodies induced against PSC in newborn mice showed avidity and bactericidal titers, similar to those obtained in adult mice, independently of the adjuvant. Evidence is presented that the inclusion of MF59 enhanced the immune response against OMV in newborn mice.
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Affiliation(s)
- Lucila O Fukasawa
- Centro de Biotecnologia, Instituto Butantan, Avenida Vital Brasil 1500, CEP 05503-900 São Paulo, Brazil
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42
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Al-Bader T, Jolley KA, Humphries HE, Holloway J, Heckels JE, Semper AE, Friedmann PS, Christodoulides M. Activation of human dendritic cells by the PorA protein of Neisseria meningitidis. Cell Microbiol 2004; 6:651-62. [PMID: 15186401 DOI: 10.1111/j.1462-5822.2004.00392.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The major porin proteins present in the outer membrane of Neisseria meningitidis, the causative agent of life-threatening meningitis and septicaemia, are believed to have potent immunostimulatory effects. In this study, the interactions between human monocyte-derived dendritic cells (mo-DC) and the PorA porin were investigated, in order to reveal the role of this protein in promoting innate and adaptive immune responses. Recombinant (r)PorA induced mo-DC maturation, as reflected by reduced receptor-mediated endocytosis, increased production of the chemokines IL-8, RANTES, MIP-1 alpha and MIP-1 beta and augmented expression of the surface markers CD40, CD54, CD80, CD86 and major histocompatibility complex class II molecules. However, rPorA induced either low level or no significant secretion of pro-inflammatory cytokines from mo-DC. The protein potently augmented the capacity of mo-DC to activate both allogeneic CD4(+) memory T-cells and CD4(+)RA(+) naïve T-cells. In addition, rPorA appeared to inhibit the production of IL-12p70 that follows from the interaction between CD40 on the mo-DC and CD40-ligand on T-cells, thereby directing T-cell differentiation towards a Th2 type response. These data demonstrate that PorA is involved in DC activation and in influencing the nature of the T-helper immune response, which are important properties for generating antibody responses required for protective immunity against meningococci and for determining the immuno-adjuvant effects of this protein.
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Affiliation(s)
- Tamara Al-Bader
- Dermatopharmacology Unit, Division of Infection, Inflammation and Repair, Southampton General Hospital, Southampton SO16 6YD, UK
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43
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Ray A, Chatterjee NS, Bhattacharya SK, Biswas T. Porin of Shigella dysenteriae enhances mRNA levels for Toll-like receptor 2 and MyD88, up-regulates CD80 of murine macrophage, and induces the release of interleukin-12. ACTA ACUST UNITED AC 2004; 39:213-9. [PMID: 14642305 DOI: 10.1016/s0928-8244(03)00233-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sera of patients convalescing from shigellosis reacted strongly and specifically with the 38,000 Da monomer of porin of Shigella dysenteriae type 1. Since human, the only natural host of S. dysenteriae type 1, recognized the protein through humoral immune response, it is of great significance to study the surface-exposed outer membrane antigen as an adjuvant. Porin treatment of CD11b+ peritoneal cavity (PerC) MPhi of BALB/c mouse was found to up-regulate CD80 on cell surface and had no effect on CD86 expression. The surface expression of CD80 got increased by 1.6-fold in the presence of gamma interferon (IFN-gamma) supporting selective regulation of the B7-1 (CD80) member of the B7 family. MPhi released 7.25 pg of interleukin-12 (IL-12) in the presence of porin. The protein in combination with IFN-gamma augmented profoundly the release of IL-12 by 2.6-fold. Porin-mediated induction of IL-12 release would therefore influence Th1-type response, known to be preferentially triggered due to up-regulation of CD80 expression. Treatment of PerC MPhi by the protein showed an increase of mRNA for both Toll-like receptor (TLR)2 and myeloid differentiation factor 88 (MyD88) by 2- and 2.3-fold respectively, emphasizing that TLR2 is essential for recognition of S. dysenteriae type 1 porin. Understanding the mechanism of adjuvanticity of porin of S. dysenteriae type 1 is a necessary step towards the development of a better adjuvant against shigellosis.
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MESH Headings
- Adaptor Proteins, Signal Transducing
- Adjuvants, Immunologic
- Animals
- Antibodies, Bacterial/blood
- Antigens, Differentiation/genetics
- Antigens, Differentiation/metabolism
- B7-1 Antigen/biosynthesis
- Blotting, Western
- Dysentery, Bacillary/immunology
- Dysentery, Bacillary/metabolism
- Female
- Humans
- Interleukin-12/metabolism
- Macrophages, Peritoneal
- Male
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/metabolism
- Mice
- Mice, Inbred BALB C
- Myeloid Differentiation Factor 88
- Porins/metabolism
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/metabolism
- Receptors, Immunologic/genetics
- Receptors, Immunologic/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Shigella dysenteriae/genetics
- Shigella dysenteriae/immunology
- Shigella dysenteriae/metabolism
- Toll-Like Receptor 2
- Toll-Like Receptors
- Up-Regulation
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Affiliation(s)
- Avijit Ray
- National Institute of Cholera and Enteric Diseases, P-33, C.I.T. Road, Scheme XM, Kolkata-700 010, West Bengal, India
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44
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Latz E, Franko J, Golenbock DT, Schreiber JR. Haemophilus influenzaeType b-Outer Membrane Protein Complex Glycoconjugate Vaccine Induces Cytokine Production by Engaging Human Toll-Like Receptor 2 (TLR2) and Requires the Presence of TLR2 for Optimal Immunogenicity. THE JOURNAL OF IMMUNOLOGY 2004; 172:2431-8. [PMID: 14764714 DOI: 10.4049/jimmunol.172.4.2431] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Conjugate vaccines consisting of the capsular polysaccharide (PS) of Haemophilus influenzae type b (Hib) covalently linked to carrier proteins, unlike pure PS, are immunogenic in infants and have significantly reduced Hib infections in the United States, but require multiple doses to induce protective anti-PS Ab titers. Hib-meningococcal outer membrane protein complex (OMPC) conjugate vaccine, however, elicits protective anti-PS Ab titers after one dose. We found that OMPC and Hib-OMPC engaged human Toll-like receptor 2 (TLR2) expressed in human embryonic kidney (HEK) cells, inducing IL-8 production, and engaged mouse TLR2 on bone marrow-derived dendritic cells, inducing TNF release. Hib conjugated to the carrier proteins CRM(197) and tetanus toxoid did not engage TLR2 on HEK or dendritic cells. Engagement of TLR2 by Hib-OMPC was MyD88 dependent, as Hib-OMPC-induced TNF production was ablated in MyD88 knockout (KO) mice. Hib-OMPC was significantly less immunogenic in TLR2 KO mice, inducing lower Hib PS IgG and IgM titers compared with those in wild-type mice. Splenocytes from OMPC-immunized TLR2 KO mice also produced significantly less IL-6 and TNF-alpha than those from wild-type mice. Hib-OMPC is unique among glycoconjugate vaccines by engaging TLR2, and the ability of Hib-OMPC to elicit protective levels of Abs after one dose may be related to TLR2-mediated induction and regulation of cytokines produced by T cells and macrophages in addition to the peptide/MHC II-dependent recruitment of T cell help commonly afforded by carrier proteins. TLR2 engagement by an adjuvant or carrier protein may be a useful strategy for augmentation of the anti-PS Ab response induced by glycoconjugate vaccines.
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MESH Headings
- Adaptor Proteins, Signal Transducing
- Animals
- Antibodies, Bacterial/biosynthesis
- Antibodies, Bacterial/blood
- Antigens, Differentiation/physiology
- Bacterial Outer Membrane Proteins/administration & dosage
- Bacterial Outer Membrane Proteins/immunology
- Bone Marrow Cells/immunology
- Bone Marrow Cells/metabolism
- Carrier Proteins/administration & dosage
- Carrier Proteins/immunology
- Cell Line
- Cells, Cultured
- Cytokines/biosynthesis
- Dendritic Cells
- Down-Regulation/genetics
- Down-Regulation/immunology
- Haemophilus Vaccines/administration & dosage
- Haemophilus Vaccines/immunology
- Humans
- Membrane Glycoproteins/biosynthesis
- Membrane Glycoproteins/deficiency
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/physiology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Myeloid Differentiation Factor 88
- Neisseria meningitidis/immunology
- Polysaccharides, Bacterial/administration & dosage
- Polysaccharides, Bacterial/immunology
- Receptors, Cell Surface/biosynthesis
- Receptors, Cell Surface/deficiency
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/physiology
- Receptors, Immunologic/physiology
- Toll-Like Receptor 2
- Toll-Like Receptors
- Tumor Necrosis Factor-alpha/metabolism
- Vaccines, Conjugate/administration & dosage
- Vaccines, Conjugate/immunology
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Affiliation(s)
- Eicke Latz
- Department of Medicine, University of Massachusetts Medical Center, Worcester, MA 01605, USA
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45
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Galdiero M, Tortora A, Damiano N, Vitiello M, Longanella A, Galdiero E. Induction of cytokine mRNA expression in U937 cells by Salmonella typhimurium porins is regulated by different phosphorylation pathways. Med Microbiol Immunol 2003; 194:13-23. [PMID: 14628144 DOI: 10.1007/s00430-003-0209-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Lipopolysaccharide (LPS) and porins of Gram-negative outer membranes are the main pathogenic factors implicated in the clinical syndrome of septic shock. The biological activity of porins and LPS are similar, but they occur by different mechanisms. It seems that porins act through different intracellular pathways with respect to LPS. In this study we analyzed the role of several inhibitors of the MEK/ERK signal pathway on the induction of proinflammatory and immunological cytokines in U937 cell line stimulated by Salmonella typhimurium porins and compared it to the cytokine induction after LPS stimulation. We investigated the effects of p38 MAP kinase inhibitor SB-203580, MEK/ERK kinase inhibitor PD-098059 and Raf-1 inhibitor forskolin, and demonstrated that they modulate cytokine mRNA expression in a different manner as a consequence of the use of porins or LPS as stimuli. TNF-alpha and IL-1beta mRNA expression is decreased by PD-098059 after stimulation with LPS but not with porins in differentiated U937 cells. IL-10 mRNA expression is inhibited by SB-203580 and PD-098059 after stimulation with porins in U937 cells. IL-6 and IL-8 mRNA expression is not changed by PD-098059 or SB-203580, after stimulation either with porins or LPS. Furthermore, mRNA expression of the studied cytokines, except for GM-CSF, is not changed using forskolin.
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Affiliation(s)
- Marilena Galdiero
- Dipartimento di Medicina Sperimentale, Facoltà di Medicina e Chirurgia, Seconda Università degli Studi di Napoli, via De Crecchio, Napoli, Italy.
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Galdiero M, Vitiello M, Galdiero S. Eukaryotic cell signaling and transcriptional activation induced by bacterial porins. FEMS Microbiol Lett 2003; 226:57-64. [PMID: 13129608 DOI: 10.1016/s0378-1097(03)00562-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The protein composition of the outer membrane of Gram-negative bacteria consists of about 20 immunochemically distinct proteins, termed outer membrane proteins (OMPs). Apart from their structural role, OMPs have been shown to have other functions, particularly with regard to transport, and have been classified as permeases and porins. Porins, during their interaction with the host, are immunogenic and also directly stimulate several cellular functions. Porins work both as molecules present on the bacterial surface and as molecules released by bacteria. Lipopolysaccharide and OMPs, the major structural macromolecular constituents of the outer membrane, carry out a fundamental role in the pathogenesis of Gram-negative infections. This brief review describes the multiple facets of the biological activities of porins both in vitro and in vivo, particularly focusing on their ability to induce the expression of cytokines and other factors that modulate cellular activities with either pathological or adaptive consequences. This brief discussion will focus on the signal transmission mechanisms induced by bacterial porins.
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Affiliation(s)
- Massimiliano Galdiero
- Dipartimento di Medicina Sperimentale, Sezione di Microbiologia e Microbiologia Clinica, Facoltà di Medicina e Chirurgia, Seconda Università degli Studi di Napoli, Via De Crecchio 7, 80138, Naples, Italy.
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Abstract
B7 costimulation plays a major role in herpes simplex virus (HSV) immunity. Effects of immunoregulatory cytokines (interferon-gamma [IFN-gamma] and interleukin-10 [IL-10]) and HSV antigens on B7-1 (CD80) and B7-2 (CD86) expression on monocytes during HSV-2 infection were investigated using flow cytometry. Our results demonstrate that HSV-2 infection effects the expression of B7 isoforms (B7-1 and B7-2) on monocytes in two ways, with opposing outcomes. It abrogates the IFN-gamma upregulation of B7-1 and B7-2 and also augments expression of B7-1 and B7-2 on monocytes through an IFN-gamma independent mechanism. The clinical significance of these opposing effects may be related to the pathogenesis of recurrent HSV disease in immunocompetent hosts.
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Affiliation(s)
- Rekha Singh
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada.
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Abstract
Cells expressing Toll-like receptor (TLR), TLR2 in association with TLR1, TLR6 or some other unknown co-receptor can respond upon interaction with a large variety of microbial ligands. The variety of TLR2 ligands is the greatest among all the TLRs and this is due to the heterodimerization needed for TLR2 mediated responses. Like other TLRs, TLR2 signaling induces antigen presenting cell activation, pro-inflammatory cytokine production and increased expression of co-stimulatory ligand expression. These events are important for induction of innate immune responses and improved acquired immunity. There is strong suggestive evidence that alteration or lack of TLR2 function in vivo may correlate to decreased immune protection from pathogens that contain TLR2 ligands, but more work needs to be performed to strengthen this correlation.
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Affiliation(s)
- Lee M Wetzler
- Department of Medicine, Division of Infectious Diseases, Boston Medical Center, Boston University School of Medicine, Evans Biomedical Research Center, Boston, MA 02118, USA.
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Abstract
Neisseria meningitidis and Neisseria gonorrhoeae are Gram-negative pathogenic bacteria responsible for bacterial meningitis and septicemia, and the sexually transmitted disease gonorrhea, respectively. Porins are the most represented outer membrane proteins in the pathogenic Neisseria species, functioning as pores for the exchange of ions, and are characterized by a trimeric beta-barrel structure. Neisserial porins have been shown to act as adjuvants in the immune response via activation of B cells and other antigen-presenting cells (APCs). Their effect on the immune response is mediated by upregulation of the costimulatory molecule B7-2 (CD86) on the surface of APCs, an effect that is Toll-like receptor 2- and MyD88-dependent. The effect of neisserial porins on the immune system also involves interaction with components of the complement cascade. Furthermore, neisserial porins co-localize with mitochondria of target cells, where they appear to modulate apoptosis.
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Affiliation(s)
- Paola Massari
- Department of Medicine, Division of Infectious Diseases, Boston University School of Medicine, Boston, MA 02118, USA
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Massari P, King CA, Ho AY, Wetzler LM. Neisserial PorB is translocated to the mitochondria of HeLa cells infected with Neisseria meningitidis and protects cells from apoptosis. Cell Microbiol 2003; 5:99-109. [PMID: 12580946 DOI: 10.1046/j.1462-5822.2003.00257.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have previously shown that purified meningococcal porin PorB associates with mitochondria and prevents apoptosis of B cells, Jurkat cells and HeLa cells (Massari et al., 2000, Proc Natl Acad Sci USA 97: 9070-9075). This work examines if intact meningococci have a similar effect as purified porins. It was first determined that intact live meningococci do not induce apoptosis of HeLa cells and do not perturb mitochondrial physiology. This latter consideration is important as Neisserial porins affect the susceptibility of cells to apoptosis by preventing mitochondrial depolarization and cytochrome c release, events involved in the apoptosis cascade. Purified PorB or PorB from live bacteria were found to translocate into and interact with mitochondria. It was then determined whether treatment of HeLa cells with meningococci could prevent staurosporine-mediated apoptosis due to an effect of PorB on the mitochondrial parameters. Incubation of HeLa cells with live meningococci prevented staurosporine-induced apoptosis, as ascertained by measurements of mitochondrial potential, translocation of mitochondrial cytochrome c to the cytosol, caspases activation, and nuclear DNA degradation. These data are consistent with our previous findings that purified PorB associates with mitochondria and prevents apoptosis, and demonstrates that the mechanism by which whole meningococci protects cells from apoptosis is a result of direct interaction of neisserial porin with mitochondria.
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Affiliation(s)
- Paola Massari
- Department of Medicine, Boston University School of Medicine, 650 Albany St, Boston, MA 02118, USA
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