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McDonald K, Rodriguez A, Muthukrishnan G. Humanized Mouse Models of Bacterial Infections. Antibiotics (Basel) 2024; 13:640. [PMID: 39061322 PMCID: PMC11273811 DOI: 10.3390/antibiotics13070640] [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: 06/05/2024] [Revised: 07/02/2024] [Accepted: 07/06/2024] [Indexed: 07/28/2024] Open
Abstract
Bacterial infections continue to represent a significant healthcare burden worldwide, causing considerable mortality and morbidity every year. The emergence of multidrug-resistant bacterial strains continues to rise, posing serious risks to controlling global disease outbreaks. To develop novel and more effective treatment and vaccination programs, there is a need for clinically relevant small animal models. Since multiple bacterial species have human-specific tropism for numerous virulence factors and toxins, conventional mouse models do not fully represent human disease. Several human disease characteristic phenotypes, such as lung granulomas in the case of Mycobacterium tuberculosis infections, are absent in standard mouse models. Alternatively, certain pathogens, such as Salmonella enterica serovar typhi and Staphylococcus aureus, can be well tolerated in mice and cleared quickly. To address this, multiple groups have developed humanized mouse models and observed enhanced susceptibility to infection and a more faithful recapitulation of human disease. In the last two decades, multiple humanized mouse models have been developed to attempt to recapitulate the human immune system in a small animal model. In this review, we first discuss the history of immunodeficient mice that has enabled the engraftment of human tissue and the engraftment methods currently used in the field. We then highlight how humanized mouse models successfully uncovered critical human immune responses to various bacterial infections, including Salmonella enterica serovar Typhi, Mycobacterium tuberculosis, and Staphylococcus aureus.
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Affiliation(s)
- Katya McDonald
- Center for Musculoskeletal Research, Department of Orthopaedics, University of Rochester Medical Center, 601 Elmwood Avenue, Box 665, Rochester, NY 14642, USA
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Adryiana Rodriguez
- Center for Musculoskeletal Research, Department of Orthopaedics, University of Rochester Medical Center, 601 Elmwood Avenue, Box 665, Rochester, NY 14642, USA
| | - Gowrishankar Muthukrishnan
- Center for Musculoskeletal Research, Department of Orthopaedics, University of Rochester Medical Center, 601 Elmwood Avenue, Box 665, Rochester, NY 14642, USA
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
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Chatterjee R, Chowdhury AR, Mukherjee D, Chakravortty D. From Eberthella typhi to Salmonella Typhi: The Fascinating Journey of the Virulence and Pathogenicity of Salmonella Typhi. ACS OMEGA 2023; 8:25674-25697. [PMID: 37521659 PMCID: PMC10373206 DOI: 10.1021/acsomega.3c02386] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 06/30/2023] [Indexed: 08/01/2023]
Abstract
Salmonella Typhi (S. Typhi), the invasive typhoidal serovar of Salmonella enterica that causes typhoid fever in humans, is a severe threat to global health. It is one of the major causes of high morbidity and mortality in developing countries. According to recent WHO estimates, approximately 11-21 million typhoid fever illnesses occur annually worldwide, accounting for 0.12-0.16 million deaths. Salmonella infection can spread to healthy individuals by the consumption of contaminated food and water. Typhoid fever in humans sometimes is accompanied by several other critical extraintestinal complications related to the central nervous system, cardiovascular system, pulmonary system, and hepatobiliary system. Salmonella Pathogenicity Island-1 and Salmonella Pathogenicity Island-2 are the two genomic segments containing genes encoding virulent factors that regulate its invasion and systemic pathogenesis. This Review aims to shed light on a comparative analysis of the virulence and pathogenesis of the typhoidal and nontyphoidal serovars of S. enterica.
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Affiliation(s)
- Ritika Chatterjee
- Department
of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, Karnataka 560012, India
| | - Atish Roy Chowdhury
- Department
of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, Karnataka 560012, India
| | - Debapriya Mukherjee
- Department
of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, Karnataka 560012, India
| | - Dipshikha Chakravortty
- Department
of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, Karnataka 560012, India
- Centre
for Biosystems Science and Engineering, Indian Institute of Science, Bangalore, Karnataka 560012, India
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3
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Identification of collaborative cross mouse strains permissive to Salmonella enterica serovar Typhi infection. Sci Rep 2023; 13:393. [PMID: 36624251 PMCID: PMC9829673 DOI: 10.1038/s41598-023-27400-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 01/02/2023] [Indexed: 01/11/2023] Open
Abstract
Salmonella enterica serovar Typhi is the causative agent of typhoid fever restricted to humans and does not replicate in commonly used inbred mice. Genetic variation in humans is far greater and more complex than that in a single inbred strain of mice. The Collaborative Cross (CC) is a large panel of recombinant inbred strains which has a wider range of genetic diversity than laboratory inbred mouse strains. We found that the CC003/Unc and CC053/Unc strains are permissive to intraperitoneal but not oral route of S. Typhi infection and show histopathological changes characteristic of human typhoid. These CC strains are immunocompetent, and immunization induces antigen-specific responses that can kill S. Typhi in vitro and control S. Typhi in vivo. Our results indicate that CC003/Unc and CC053/Unc strains can help identify the genetic basis for typhoid susceptibility, S. Typhi virulence mechanism(s) in vivo, and serve as a preclinical mammalian model system to identify effective vaccines and therapeutics strategies.
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Stepien TA, Libby SJ, Karlinsey JE, Brehm MA, Greiner DL, Shultz LD, Brabb T, Fang FC. Analysis of Salmonella Typhi Pathogenesis in a Humanized Mouse Model. Methods Mol Biol 2022; 2427:215-234. [PMID: 35619037 PMCID: PMC9682973 DOI: 10.1007/978-1-0716-1971-1_18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Efforts to understand molecular mechanisms of pathogenesis of the human-restricted pathogen Salmonella enterica serovar Typhi, the causative agent of typhoid fever, have been hampered by the lack of a tractable small animal model. This obstacle has been surmounted by a humanized mouse model in which genetically modified mice are engrafted with purified CD34+ stem cells from human umbilical cord blood, designated CD34+ Hu-NSG (formerly hu-SRC-SCID) mice. We have shown that these mice develop a lethal systemic infection with S. Typhi that is dependent on the presence of engrafted human hematopoietic cells. Immunological and pathological features of human typhoid are recapitulated in this model, which has been successfully employed for the identification of bacterial genetic determinants of S. Typhi virulence. Here we describe the methods used to infect CD34+ Hu-NSG mice with S. Typhi in humanized mice and to construct and analyze a transposon-directed insertion site sequencing S. Typhi library, and provide general considerations for the use of humanized mice for the study of a human-restricted pathogen.
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Affiliation(s)
- Taylor A Stepien
- Department of Global Health, University of Washington, Seattle, WA, USA
| | - Stephen J Libby
- Department of Laboratory Medicine & Pathology, University of Washington, Seattle, WA, USA
| | - Joyce E Karlinsey
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Michael A Brehm
- Department of Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Dale L Greiner
- Department of Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | | | - Thea Brabb
- Department of Comparative Medicine, University of Washington, Seattle, WA, USA
| | - Ferric C Fang
- Department of Global Health, University of Washington, Seattle, WA, USA.,Department of Laboratory Medicine & Pathology, University of Washington, Seattle, WA, USA.,Department of Microbiology, University of Washington, Seattle, WA, USA
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5
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Alisjahbana A, Mohammad I, Gao Y, Evren E, Ringqvist E, Willinger T. Human macrophages and innate lymphoid cells: Tissue-resident innate immunity in humanized mice. Biochem Pharmacol 2019; 174:113672. [PMID: 31634458 DOI: 10.1016/j.bcp.2019.113672] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 10/15/2019] [Indexed: 12/17/2022]
Abstract
Macrophages and innate lymphoid cells (ILCs) are tissue-resident cells that play important roles in organ homeostasis and tissue immunity. Their intricate relationship with the organs they reside in allows them to quickly respond to perturbations of organ homeostasis and environmental challenges, such as infection and tissue injury. Macrophages and ILCs have been extensively studied in mice, yet important species-specific differences exist regarding innate immunity between humans and mice. Complementary to ex-vivo studies with human cells, humanized mice (i.e. mice with a human immune system) offer the opportunity to study human macrophages and ILCs in vivo within their surrounding tissue microenvironments. In this review, we will discuss how humanized mice have helped gain new knowledge about the basic biology of these cells, as well as their function in infectious and malignant conditions. Furthermore, we will highlight active areas of investigation related to human macrophages and ILCs, such as their cellular heterogeneity, ontogeny, tissue residency, and plasticity. In the near future, we expect more fundamental discoveries in these areas through the combined use of improved humanized mouse models together with state-of-the-art technologies, such as single-cell RNA-sequencing and CRISPR/Cas9 genome editing.
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Affiliation(s)
- Arlisa Alisjahbana
- Center for Infectious Medicine, Karolinska Institutet, Alfred Nobels allé 8, 141 52 Stockholm, Sweden
| | - Imran Mohammad
- Center for Infectious Medicine, Karolinska Institutet, Alfred Nobels allé 8, 141 52 Stockholm, Sweden
| | - Yu Gao
- Center for Infectious Medicine, Karolinska Institutet, Alfred Nobels allé 8, 141 52 Stockholm, Sweden
| | - Elza Evren
- Center for Infectious Medicine, Karolinska Institutet, Alfred Nobels allé 8, 141 52 Stockholm, Sweden
| | - Emma Ringqvist
- Center for Infectious Medicine, Karolinska Institutet, Alfred Nobels allé 8, 141 52 Stockholm, Sweden
| | - Tim Willinger
- Center for Infectious Medicine, Karolinska Institutet, Alfred Nobels allé 8, 141 52 Stockholm, Sweden.
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Li Y, Di Santo JP. Modeling Infectious Diseases in Mice with a "Humanized" Immune System. Microbiol Spectr 2019; 7:10.1128/microbiolspec.bai-0019-2019. [PMID: 30953434 PMCID: PMC11590424 DOI: 10.1128/microbiolspec.bai-0019-2019] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Indexed: 01/07/2023] Open
Abstract
Human immune system (HIS) mice are created by transplanting human immune cells or their progenitor cells into highly immunodeficient recipient mouse hosts, thereby "humanizing" their immune systems. Over past decades, the field of HIS mice has evolved rapidly, as modifications of existing immunodeficient mouse strains have been developed, resulting in increasing levels of human tissue engraftment as humanization is optimized. Current HIS mouse models not only permit elevated levels of human cell engraftment but also demonstrate graft stability. As such, HIS mice are being extensively used to study the human innate and adaptive immune response against microbial infections in vivo. Compared to nonhumanized animal models, which are frequently infected with surrogate or adapted microbes, the HIS mouse models allow the analysis of interactions between human immune cells and bona fide pathogenic microbes, making them a more clinically relevant model. This article reviews the development of HIS mice and covers the different strategies used to humanize mice, as well as discussing the use of HIS mice for studying bacterial infections that cause human disease.
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Affiliation(s)
- Yan Li
- Innate Immunity Unit, Immunology Department, Institut Pasteur, Paris, France
- Inserm U1223, Paris, France
| | - James P Di Santo
- Innate Immunity Unit, Immunology Department, Institut Pasteur, Paris, France
- Inserm U1223, Paris, France
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8
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Yin Y, Zhou D. Organoid and Enteroid Modeling of Salmonella Infection. Front Cell Infect Microbiol 2018; 8:102. [PMID: 29670862 PMCID: PMC5894114 DOI: 10.3389/fcimb.2018.00102] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 03/16/2018] [Indexed: 12/12/2022] Open
Abstract
Salmonella are Gram-negative rod-shaped facultative anaerobic bacteria that are comprised of over 2,000 serovars. They cause gastroenteritis (salmonellosis) with headache, abdominal pain and diarrhea clinical symptoms. Salmonellosis brings a heavy burden for the public health in both developing and developed countries. Antibiotics are usually effective in treating the infected patients with severe gastroenteritis, although antibiotic resistance is on the rise. Understanding the molecular mechanisms of Salmonella infection is vital to combat the disease. In vitro immortalized 2-D cell lines, ex vivo tissues/organs and several animal models have been successfully utilized to study Salmonella infections. Although these infection models have contributed to uncovering the molecular virulence mechanisms, some intrinsic shortcomings have limited their wider applications. Notably, cell lines only contain a single cell type, which cannot reproduce some of the hallmarks of natural infections. While ex vivo tissues/organs alleviate some of these concerns, they are more difficult to maintain, in particular for long term experiments. In addition, non-human animal models are known to reflect only part of the human disease process. Enteroids and induced intestinal organoids are emerging as effective infection models due to their closeness in mimicking the infected tissues/organs. Induced intestinal organoids are derived from iPSCs and contain mesenchymal cells whereas enteroids are derive from intestinal stem cells and are comprised of epithelial cells only. Both enteroids and induced intestinal organoids mimic the villus and crypt domains comparable to the architectures of the in vivo intestine. We review here that enteroids and induced intestinal organoids are emerging as desired infection models to study bacterial-host interactions of Salmonella.
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Affiliation(s)
- Yuebang Yin
- Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center, Rotterdam, Netherlands
| | - Daoguo Zhou
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China.,Department of Biological Sciences, Purdue University, West Lafayette, IN, United States
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9
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Frequency of Human CD45+ Target Cells is a Key Determinant of Intravaginal HIV-1 Infection in Humanized Mice. Sci Rep 2017; 7:15263. [PMID: 29127409 PMCID: PMC5681573 DOI: 10.1038/s41598-017-15630-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 10/31/2017] [Indexed: 02/08/2023] Open
Abstract
Approximately 40% of HIV-1 infections occur in the female genital tract (FGT), primarily through heterosexual transmission. FGT factors determining outcome of HIV-1 exposure are incompletely understood, limiting prevention strategies. Here, humanized NOD-Rag1−/− γc−/− mice differentially reconstituted with human CD34+ -enriched hematopoietic stem cells (Hu-mice), were used to assess target cell frequency and viral inoculation dose as determinants of HIV-1 infection following intravaginal (IVAG) challenge. Results revealed a significant correlation between HIV-1 susceptibility and hCD45+ target cells in the blood, which correlated with presence of target cells in the FGT, in the absence of local inflammation. HIV-1 plasma load was associated with viral dose at inoculation and frequency of target cells. Events following IVAG HIV-1 infection; viral dissemination and CD4 depletion, were not affected by these parameters. Following IVAG inoculation, HIV-1 titres peaked, then declined in vaginal lavage while plasma showed a reciprocal pattern. The greatest frequency of HIV-1-infected (p24+) cells were found one week post-infection in the FGT versus blood and spleen, suggesting local viral amplification. Five weeks post-infection, HIV-1 disseminated into systemic tissues, in a dose-dependent manner, followed by depletion of hCD45+ CD3+ CD4+ cells. Results indicate target cell frequency in the Hu-mouse FGT is a key determinant of HIV-1 infection, which might provide a useful target for prophylaxis in women.
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Walker JA, Vuyyuru R, Manser T, Alugupalli KR. Humoral Immunity in Mice Transplanted with Hematopoietic Stem Cells Derived from Human Umbilical Cord Blood Recapitulates That of Human Infants. Stem Cells Dev 2017; 26:1715-1723. [PMID: 29099340 DOI: 10.1089/scd.2017.0156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Immunodeficient mice transplanted with human hematopoietic stem cells (HSCs) have been referred to as "Human Immune System" (HIS) mice and are a translational platform for studying human immune responses in vivo. Human HSC sources used in generating HIS mice include fetal liver (FL), umbilical cord blood (CB), and adult bone marrow (BM). Since HSCs from FL, CB, and BM are produced at various stages of human development, we tested whether mice transplanted with these three HSCs differ in their immune responses. We found that compared with CB HSCs or FL HSCs, adult BM HSCs reconstitute the immune system poorly. The resulting HIS mice do not mount an antibody response to Borrelia hermsii infection and as a consequence suffer persistently high levels of bacteremia. While both CB and FL HSCs yield comparable levels of immune reconstitution of HIS mice resulting in robust anti-B. hermsii immune responses, FL HSC-transplanted mice exhibited a discernable difference in their human B cell maturity as identified by an increased frequency of CD10+ immature B cells and relatively smaller lymphoid follicles compared with CB HSC-transplanted mice. Although CB HSC-transplanted mice generated robust antibody responses to B. hermsii and specific protein antigens of B. hermsii, they failed to respond to Salmonella typhi Vi polysaccharide, a classical T cell-independent antigen. This situation resembles that seen in human infants and young children. Therefore, CB HSC-transplanted mice may serve as a translation platform to explore approaches to overcome the impaired antipolysaccharide responses characteristic of human infants.
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Affiliation(s)
- Justin A Walker
- Department of Microbiology and Immunology, Sidney Kimmel Cancer Center, Sidney Kimmel Medical College, Thomas Jefferson University , Philadelphia, Pennsylvania
| | - Raja Vuyyuru
- Department of Microbiology and Immunology, Sidney Kimmel Cancer Center, Sidney Kimmel Medical College, Thomas Jefferson University , Philadelphia, Pennsylvania
| | - Tim Manser
- Department of Microbiology and Immunology, Sidney Kimmel Cancer Center, Sidney Kimmel Medical College, Thomas Jefferson University , Philadelphia, Pennsylvania
| | - Kishore R Alugupalli
- Department of Microbiology and Immunology, Sidney Kimmel Cancer Center, Sidney Kimmel Medical College, Thomas Jefferson University , Philadelphia, Pennsylvania
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Kurtz JR, Goggins JA, McLachlan JB. Salmonella infection: Interplay between the bacteria and host immune system. Immunol Lett 2017; 190:42-50. [PMID: 28720334 DOI: 10.1016/j.imlet.2017.07.006] [Citation(s) in RCA: 170] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 07/07/2017] [Accepted: 07/10/2017] [Indexed: 12/14/2022]
Abstract
Salmonella infection causes morbidity and mortality throughout the world with the host immune response varying depending on whether the infection is acute and limited, or systemic and chronic. Additionally, Salmonella bacteria have evolved multiple mechanisms to avoid or subvert immunity to its own benefit and often the anatomical location of infection plays a role in both the immune response and bacterial fate. Here, we provide an overview of the interplay between the immune system and Salmonella, while discussing how different host and bacterial factors influence the outcome of infection.
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Affiliation(s)
- Jonathan R Kurtz
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA, United States
| | - J Alan Goggins
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA, United States
| | - James B McLachlan
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA, United States.
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12
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Grover A, Troy A, Rowe J, Troudt JM, Creissen E, McLean J, Banerjee P, Feuer G, Izzo AA. Humanized NOG mice as a model for tuberculosis vaccine-induced immunity: a comparative analysis with the mouse and guinea pig models of tuberculosis. Immunology 2017; 152:150-162. [PMID: 28502122 DOI: 10.1111/imm.12756] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 04/09/2017] [Accepted: 05/01/2017] [Indexed: 12/13/2022] Open
Abstract
The humanized mouse model has been developed as a model to identify and characterize human immune responses to human pathogens and has been used to better identify vaccine candidates. In the current studies, the humanized mouse was used to determine the ability of a vaccine to affect the immune response to infection with Mycobacterium tuberculosis. Both human CD4+ and CD8+ T cells responded to infection in humanized mice as a result of infection. In humanized mice vaccinated with either BCG or with CpG-C, a liposome-based formulation containing the M. tuberculosis antigen ESAT-6, both CD4 and CD8 T cells secreted cytokines that are known to be required for induction of protective immunity. In comparison to the C57BL/6 mouse model and Hartley guinea pig model of tuberculosis, data obtained from humanized mice complemented the data observed in the former models and provided further evidence that a vaccine can induce a human T-cell response. Humanized mice provide a crucial pre-clinical platform for evaluating human T-cell immune responses in vaccine development against M. tuberculosis.
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Affiliation(s)
- Ajay Grover
- Department of Microbiology, Immunology & Pathology, Colorado State University, Fort Collins, CO, USA
| | - Amber Troy
- Department of Microbiology, Immunology & Pathology, Colorado State University, Fort Collins, CO, USA
| | - Jenny Rowe
- HuMurine Technologies, La Verne, CA, USA
| | - JoLynn M Troudt
- Department of Microbiology, Immunology & Pathology, Colorado State University, Fort Collins, CO, USA
| | - Elizabeth Creissen
- Department of Microbiology, Immunology & Pathology, Colorado State University, Fort Collins, CO, USA
| | - Jennifer McLean
- Department of Microbiology, Immunology & Pathology, Colorado State University, Fort Collins, CO, USA
| | | | | | - Angelo A Izzo
- Department of Microbiology, Immunology & Pathology, Colorado State University, Fort Collins, CO, USA
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Abstract
Salmonella enterica subspecies enterica includes several serovars infecting both humans and other animals and leading to typhoid fever or gastroenteritis. The high prevalence of associated morbidity and mortality, together with an increased emergence of multidrug-resistant strains, is a current global health issue that has prompted the development of vaccination strategies that confer protection against most serovars. Currently available systemic vaccine approaches have major limitations, including a reduced effectiveness in young children and a lack of cross-protection among different strains. Having studied host-pathogen interactions, microbiologists and immunologists argue in favor of topical gastrointestinal administration for improvement in vaccine efficacy. Here, recent advances in this field are summarized, including mechanisms of bacterial uptake at the intestinal epithelium, the assessment of protective host immunity, and improved animal models that closely mimic infection in humans. The pros and cons of existing vaccines are presented, along with recent progress made with novel formulations. Finally, new candidate antigens and their relevance in the refined design of anti-Salmonella vaccines are discussed, along with antigen vectorization strategies such as nanoparticles or secretory immunoglobulins, with a focus on potentiating mucosal vaccine efficacy.
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Nithichanon A, Gourlay LJ, Bancroft GJ, Ato M, Takahashi Y, Lertmemongkolchai G. Boosting of post-exposure human T-cell and B-cell recall responses in vivo by Burkholderia pseudomallei-related proteins. Immunology 2017; 151:98-109. [PMID: 28066900 DOI: 10.1111/imm.12709] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2016] [Revised: 12/30/2016] [Accepted: 01/04/2017] [Indexed: 12/20/2022] Open
Abstract
Burkholderia pseudomallei is the causative agent of melioidosis, an infectious disease with high incidence and mortality in South East Asia and northern Australia. To date there is no protective vaccine and antibiotic treatment is prolonged and not always effective. Most people living in endemic areas have been exposed to the bacteria and have developed some immunity, which may have helped to prevent disease. Here, we used a humanized mouse model (hu-PBL-SCID), reconstituted with human peripheral blood mononuclear cells from seropositive donors, to illustrate the potential of three known antigens (FliC, OmpA and N-PilO2) for boosting both T-cell and B-cell immune responses. All three antigens boosted the production of specific antibodies in vivo, and increased the number of antibody and interferon-γ-secreting cells, and induced antibody affinity maturation. Moreover, antigen-specific antibodies isolated from either seropositive individuals or boosted mice, were found to enhance phagocytosis and oxidative burst activities from human polymorphonuclear cells. Our study demonstrates that FliC, OmpA and N-PilO2 can stimulate human memory T and B cells and highlight the potential of the hu-PBL-SCID system for screening and evaluation of novel protein antigens for inclusion in future vaccine trials against melioidosis.
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Affiliation(s)
- Arnone Nithichanon
- The Centre for Research and Development of Medical Diagnostic Laboratories, Khon Kaen University, Khon Kaen, Thailand
| | | | | | - Manabu Ato
- Department of Immunology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Yoshimasa Takahashi
- Department of Immunology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Ganjana Lertmemongkolchai
- The Centre for Research and Development of Medical Diagnostic Laboratories, Khon Kaen University, Khon Kaen, Thailand
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Walsh NC, Kenney LL, Jangalwe S, Aryee KE, Greiner DL, Brehm MA, Shultz LD. Humanized Mouse Models of Clinical Disease. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2016; 12:187-215. [PMID: 27959627 DOI: 10.1146/annurev-pathol-052016-100332] [Citation(s) in RCA: 402] [Impact Index Per Article: 44.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Immunodeficient mice engrafted with functional human cells and tissues, that is, humanized mice, have become increasingly important as small, preclinical animal models for the study of human diseases. Since the description of immunodeficient mice bearing mutations in the IL2 receptor common gamma chain (IL2rgnull) in the early 2000s, investigators have been able to engraft murine recipients with human hematopoietic stem cells that develop into functional human immune systems. These mice can also be engrafted with human tissues such as islets, liver, skin, and most solid and hematologic cancers. Humanized mice are permitting significant progress in studies of human infectious disease, cancer, regenerative medicine, graft-versus-host disease, allergies, and immunity. Ultimately, use of humanized mice may lead to the implementation of truly personalized medicine in the clinic. This review discusses recent progress in the development and use of humanized mice and highlights their utility for the study of human diseases.
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Affiliation(s)
- Nicole C Walsh
- Department of Molecular Medicine, Diabetes Center of Excellence, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Laurie L Kenney
- Department of Molecular Medicine, Diabetes Center of Excellence, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Sonal Jangalwe
- Department of Molecular Medicine, Diabetes Center of Excellence, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Ken-Edwin Aryee
- Department of Molecular Medicine, Diabetes Center of Excellence, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Dale L Greiner
- Department of Molecular Medicine, Diabetes Center of Excellence, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Michael A Brehm
- Department of Molecular Medicine, Diabetes Center of Excellence, University of Massachusetts Medical School, Worcester, Massachusetts 01605
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Animal Models for Salmonellosis: Applications in Vaccine Research. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2016; 23:746-56. [PMID: 27413068 DOI: 10.1128/cvi.00258-16] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Salmonellosis remains an important cause of human disease worldwide. While there are several licensed vaccines for Salmonella enterica serovar Typhi, these vaccines are generally ineffective against other Salmonella serovars. Vaccines that target paratyphoid and nontyphoidal Salmonella serovars are very much in need. Preclinical evaluation of candidate vaccines is highly dependent on the availability of appropriate scientific tools, particularly animal models. Many different animal models exist for various Salmonella serovars, from whole-animal models to smaller models, such as those recently established in insects. Here, we discuss various mouse, rat, rabbit, calf, primate, and insect models for Salmonella infection, all of which have their place in research. However, choosing the right model is imperative in selecting the best vaccine candidates for further clinical testing. In this minireview, we summarize the various animal models that are used to assess salmonellosis, highlight some of the advantages and disadvantages of each, and discuss their value in vaccine development.
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Ernst W. Humanized mice in infectious diseases. Comp Immunol Microbiol Infect Dis 2016; 49:29-38. [PMID: 27865261 DOI: 10.1016/j.cimid.2016.08.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 08/12/2016] [Accepted: 08/12/2016] [Indexed: 02/06/2023]
Abstract
The pathogenesis of infectious agents with human tropism can only be properly studied in an in vivo model featuring human cells or tissue. Humanized mice represent a small animal model featuring human cells or tissue that can be infected by human-specific viruses, bacteria, and parasites and also providing a functional human immune system. This makes the analysis of a human immune response to infection possible and allows for preclinical testing of new vaccines and therapeutic agents. Results of various studies using humanized mice to investigate pathogens with human tropism are presented in this review. In addition, the limitations of humanized mice and methods to improve this valuable animal model are discussed.
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Affiliation(s)
- W Ernst
- Clinic of Gynecology and Obstetrics St. Hedwig, University of Regensburg, Regensburg, Bavaria, Germany.
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18
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Vendrell A, Mongini C, Gravisaco MJ, Canellada A, Tesone AI, Goin JC, Waldner CI. An Oral Salmonella-Based Vaccine Inhibits Liver Metastases by Promoting Tumor-Specific T-Cell-Mediated Immunity in Celiac and Portal Lymph Nodes: A Preclinical Study. Front Immunol 2016; 7:72. [PMID: 26973649 PMCID: PMC4771756 DOI: 10.3389/fimmu.2016.00072] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 02/15/2016] [Indexed: 12/12/2022] Open
Abstract
Primary tumor excision is one of the most widely used therapies of cancer. However, the risk of metastases development still exists following tumor resection. The liver is a common site of metastatic disease for numerous cancers. Breast cancer is one of the most frequent sources of metastases to the liver. The aim of this work was to evaluate the efficacy of the orally administered Salmonella Typhi vaccine strain CVD 915 on the development of liver metastases in a mouse model of breast cancer. To this end, one group of BALB/c mice was orogastrically immunized with CVD 915, while another received PBS as a control. After 24 h, mice were injected with LM3 mammary adenocarcinoma cells into the spleen and subjected to splenectomy. This oral Salmonella-based vaccine produced an antitumor effect, leading to a decrease in the number and volume of liver metastases. Immunization with Salmonella induced an early cellular immune response in mice. This innate stimulation rendered a large production of IFN-γ by intrahepatic immune cells (IHIC) detected within 24 h. An antitumor adaptive immunity was found in the liver and celiac and portal lymph nodes (LDLN) 21 days after oral bacterial inoculation. The antitumor immune response inside the liver was associated with increased CD4+ and dendritic cell populations as well as with an inflammatory infiltrate located around liver metastatic nodules. Enlarged levels of inflammatory cytokines (IFN-γ and TNF) were also detected in IHIC. Furthermore, a tumor-specific production of IFN-γ and TNF as well as tumor-specific IFN-γ-producing CD8 T cells (CD8+IFN-γ+) were found in the celiac and portal lymph nodes of Salmonella-treated mice. This study provides first evidence for the involvement of LDLN in the development of an efficient cellular immune response against hepatic tumors, which resulted in the elimination of liver metastases after oral Salmonella-based vaccination.
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Affiliation(s)
- Alejandrina Vendrell
- Centro de Estudios Farmacológicos y Botánicos-Consejo Nacional de Investigaciones Científicas y Técnicas (CEFyBO-CONICET), Facultad de Medicina, Universidad de Buenos Aires , Buenos Aires , Argentina
| | - Claudia Mongini
- Centro de Estudios Farmacológicos y Botánicos-Consejo Nacional de Investigaciones Científicas y Técnicas (CEFyBO-CONICET), Facultad de Medicina, Universidad de Buenos Aires , Buenos Aires , Argentina
| | - María José Gravisaco
- Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria (INTA) , Buenos Aires , Argentina
| | - Andrea Canellada
- Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni (IDEHU). Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires , Buenos Aires , Argentina
| | - Agustina Inés Tesone
- Centro de Estudios Farmacológicos y Botánicos-Consejo Nacional de Investigaciones Científicas y Técnicas (CEFyBO-CONICET), Facultad de Medicina, Universidad de Buenos Aires , Buenos Aires , Argentina
| | - Juan Carlos Goin
- Centro de Estudios Farmacológicos y Botánicos-Consejo Nacional de Investigaciones Científicas y Técnicas (CEFyBO-CONICET), Facultad de Medicina, Universidad de Buenos Aires , Buenos Aires , Argentina
| | - Claudia Inés Waldner
- Centro de Estudios Farmacológicos y Botánicos-Consejo Nacional de Investigaciones Científicas y Técnicas (CEFyBO-CONICET), Facultad de Medicina, Universidad de Buenos Aires , Buenos Aires , Argentina
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Abstract
The new-generation humanized (Hu) mouse models permit multilineage human hematopoiesis and generate T cells, B cells, macrophages, and dendritic cells required for a coordinated human immune response. Therefore, any desired antigen or human-specific pathogens that can infect humanized mice can be used to generate human antibody responses. Two leading humanized mouse models are currently being used. The Hu-HSC model uses the transplantation of human hematopoietic stem cells (HSCs), whereas the BLT mouse model is created by transplantation of human fetal liver, thymus, and HSC. A number of human pathogens such as HIV-1, dengue, Epstein-Barr virus, and hepatitis C virus have been studied in these systems. Responder antigen-specific B cells from these animals can be collected and used to generate human monoclonals by B-cell immortalization or by single-cell PCR methods to "rescue" antibody-producing genes for ectopic expression. Both models generate cellular and humoral immune responses. However, the antibodies generated are primarily of the IgM type because of the inefficient immunoglobulin class switch resulting in the suboptimal production of antigen-specific affinity-matured IgG. The current Hu mouse models thus far have permitted the analysis of human "antibodyome," and recent reports demonstrated their utility in generating human monoclonal antibodies. Ongoing efforts at further refinements are expected to make these systems more efficient in the near future.
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20
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Kinnear CL, Strugnell RA. Vaccination Method Affects Immune Response and Bacterial Growth but Not Protection in the Salmonella Typhimurium Animal Model of Typhoid. PLoS One 2015; 10:e0141356. [PMID: 26509599 PMCID: PMC4625024 DOI: 10.1371/journal.pone.0141356] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Accepted: 10/07/2015] [Indexed: 01/22/2023] Open
Abstract
Understanding immune responses elicited by vaccines, together with immune responses required for protection, is fundamental to designing effective vaccines and immunisation programs. This study examines the effects of the route of administration of a live attenuated vaccine on its interactions with, and stimulation of, the murine immune system as well as its ability to increase survival and provide protection from colonisation by a virulent challenge strain. We assess the effect of administration method using the murine model for typhoid, where animals are infected with S. Typhimurium. Mice were vaccinated either intravenously or orally with the same live attenuated S. Typhimurium strain and data were collected on vaccine strain growth, shedding and stimulation of antibodies and cytokines. Following vaccination, mice were challenged with a virulent strain of S. Typhimurium and the protection conferred by the different vaccination routes was measured in terms of challenge suppression and animal survival. The main difference in immune stimulation found in this study was the development of a secretory IgA response in orally-vaccinated mice, which was absent in IV vaccinated mice. While both strains showed similar protection in terms of challenge suppression in systemic organs (spleen and liver) as well as survival, they differed in terms of challenge suppression of virulent pathogens in gut-associated organs. This difference in gut colonisation presents important questions around the ability of vaccines to prevent shedding and transmission. These findings demonstrate that while protection conferred by two vaccines can appear to be the same, the mechanisms controlling the protection can differ and have important implications for infection dynamics within a population.
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Affiliation(s)
- Clare L. Kinnear
- Department of Microbiology and Immunology, The University of Melbourne, Melbourne, Victoria, Australia
- Department of Biosciences, The University of Melbourne, Melbourne, Victoria, Australia
- * E-mail:
| | - Richard A. Strugnell
- Department of Microbiology and Immunology, The University of Melbourne, Melbourne, Victoria, Australia
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21
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Pham OH, McSorley SJ. Protective host immune responses to Salmonella infection. Future Microbiol 2015; 10:101-10. [PMID: 25598340 DOI: 10.2217/fmb.14.98] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Salmonella enterica serovars Typhi and Paratyphi are the causative agents of human typhoid fever. Current typhoid vaccines are ineffective and are not widely used in endemic areas. Greater understanding of host-pathogen interactions during Salmonella infection should facilitate the development of improved vaccines to combat typhoid and nontyphoidal Salmonellosis. This review will focus on our current understanding of Salmonella pathogenesis and the major host immune components that participate in immunity to Salmonella infection. In addition, recent findings regarding host immune mechanisms in response to Salmonella infection will be also discussed, providing a new perspective on the utility of improved tools to study the immune response to Salmonella infections.
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Affiliation(s)
- Oanh H Pham
- Center for Comparative Medicine, Department of Anatomy, Physiology & Cell Biology, School of Veterinary Medicine, University of California Davis, Davis, CA 95616, USA
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22
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Abstract
Salmonella are a common source of food- or water-borne infection and cause a wide range of clinical disease in human and animal hosts. Salmonella are relatively easy to culture and manipulate in a laboratory setting, and the infection of laboratory animals induces robust innate and adaptive immune responses. Thus, immunologists have frequently turned to Salmonella infection models to expand understanding of host immunity to intestinal pathogens. In this review, I summarize current knowledge of innate and adaptive immunity to Salmonella and highlight features of this response that have emerged from recent studies. These include the heterogeneity of the antigen-specific T-cell response to intestinal infection, the prominence of microbial mechanisms to impede T- and B-cell responses, and the contribution of non-cognate pathways for elicitation of T-cell effector functions. Together, these different issues challenge an overly simplistic view of host-pathogen interaction during mucosal infection, but also allow deeper insight into the real-world dynamic of protective immunity to intestinal pathogens.
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Affiliation(s)
- Stephen J McSorley
- Center for Comparative Medicine, Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California Davis, Davis, CA, USA
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23
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Gal-Mor O, Boyle EC, Grassl GA. Same species, different diseases: how and why typhoidal and non-typhoidal Salmonella enterica serovars differ. Front Microbiol 2014; 5:391. [PMID: 25136336 PMCID: PMC4120697 DOI: 10.3389/fmicb.2014.00391] [Citation(s) in RCA: 337] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 07/12/2014] [Indexed: 12/22/2022] Open
Abstract
Human infections by the bacterial pathogen Salmonella enterica represent major disease burdens worldwide. This highly ubiquitous species consists of more than 2600 different serovars that can be divided into typhoidal and non-typhoidal Salmonella (NTS) serovars. Despite their genetic similarity, these two groups elicit very different diseases and distinct immune responses in humans. Comparative analyses of the genomes of multiple Salmonella serovars have begun to explain the basis of the variation in disease manifestations. Recent advances in modeling both enteric fever and intestinal gastroenteritis in mice will facilitate investigation into both the bacterial- and host-mediated mechanisms involved in salmonelloses. Understanding the genetic and molecular mechanisms responsible for differences in disease outcome will augment our understanding of Salmonella pathogenesis, host immunity, and the molecular basis of host specificity. This review outlines the differences in epidemiology, clinical manifestations, and the human immune response to typhoidal and NTS infections and summarizes the current thinking on why these differences might exist.
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Affiliation(s)
- Ohad Gal-Mor
- The Infectious Diseases Research Laboratory, Sheba Medical Center Tel-Hashomer, Israel
| | - Erin C Boyle
- Bernhard Nocht Institute for Tropical Medicine Hamburg, Germany
| | - Guntram A Grassl
- Institute for Experimental Medicine, Christian Albrechts University Kiel Kiel, Germany ; Research Center Borstel Borstel, Germany
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24
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Foote JB, Kabir FML, Graff EC, Cattley RC, DeInnocentes P, Smith BF, Bird RC. Engraftment of canine peripheral blood lymphocytes into nonobese diabetic-severe combined immune deficient IL-2R common gamma chain null mice. Vet Immunol Immunopathol 2014; 157:131-41. [DOI: 10.1016/j.vetimm.2013.11.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 11/07/2013] [Accepted: 11/25/2013] [Indexed: 01/04/2023]
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25
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Strugnell RA, Scott TA, Wang N, Yang C, Peres N, Bedoui S, Kupz A. Salmonella vaccines: lessons from the mouse model or bad teaching? Curr Opin Microbiol 2014; 17:99-105. [PMID: 24440968 DOI: 10.1016/j.mib.2013.12.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 12/15/2013] [Accepted: 12/16/2013] [Indexed: 10/25/2022]
Abstract
Salmonella enterica subsp. enterica includes several very important human serovars including Typhi, Paratyphi, Typhimurium and Enteritidis. These bacteria cause a significant global burden of disease, typically classified into enteric fever, gastroenteritis and, more recently, invasive non-typhoidal salmonellosis (iNTS). Vaccines have been developed for one of these serovars, S. Typhi and the recent increase in iNTS cases has resulted in a push to develop new vaccines that will inhibit disease by S. Typhimurium and S. Enteritidis, the most common iNTS S. enterica serovars. The development of new human vaccines has been informed by studies in the murine model of typhoid fever based on S. Typhimurium infections of very 'sensitive' (Nramp-1(S)) mice, which has some obvious deficiencies, not the least that antibodies protect humans against S. Typhi infection but are only weakly protective in 'sensitive' mice infected with S. Typhimurium. S. Typhimurium also lacks Vi, the target of protective antibodies in typhoid fever. Notwithstanding these deficiencies, the murine model has identified a very complex series of innate and adaptive immune responses to infection that might be exploited to develop new vaccines. Equally, advances in understanding the pathogenesis of infection, through pathogenomics and more sophisticated animal models will likely contribute to the development of novel immunogens.
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Affiliation(s)
- Richard A Strugnell
- Department of Microbiology and Immunology, University of Melbourne, Parkville, VIC 3010, Australia.
| | - Timothy A Scott
- Department of Microbiology and Immunology, University of Melbourne, Parkville, VIC 3010, Australia
| | - Nancy Wang
- Department of Microbiology and Immunology, University of Melbourne, Parkville, VIC 3010, Australia
| | - Chenying Yang
- Department of Microbiology and Immunology, University of Melbourne, Parkville, VIC 3010, Australia
| | - Newton Peres
- Department of Microbiology and Immunology, University of Melbourne, Parkville, VIC 3010, Australia
| | - Sammy Bedoui
- Department of Microbiology and Immunology, University of Melbourne, Parkville, VIC 3010, Australia
| | - Andreas Kupz
- Department of Microbiology and Immunology, University of Melbourne, Parkville, VIC 3010, Australia
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26
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Abstract
Streptococcus pneumoniae still causes severe morbidity and mortality worldwide, especially in young children and the elderly. Much effort has been dedicated to developing protein-based universal vaccines to conquer the current shortcomings of capsular vaccines and capsular conjugate vaccines, such as serotype replacement, limited coverage and high costs. A recombinant live vector vaccine delivering protective antigens is a promising way to achieve this goal. In this review, we discuss the researches using live recombinant vaccines, mainly live attenuated Salmonella and lactic acid bacteria, to deliver pneumococcal antigens. We also discuss both the limitations and the future of these vaccines.
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27
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Abstract
Most pathogens are able to infect multiple hosts but some are highly adapted to a single-host species. A detailed understanding of the basis of host specificity can provide important insights into molecular pathogenesis, the evolution of pathogenic microbes, and the potential for pathogens to cross the species barrier to infect new hosts. Comparative genomics and the development of humanized mouse models have provided important new tools with which to explore the basis of generalism and specialism. This review will examine host specificity of bacterial pathogens with a focus on generalist and specialist serovars of Salmonella enterica.
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Affiliation(s)
- Andreas Bäumler
- Department of Medical Microbiology and Immunology, University of California, Davis School of Medicine, Davis, California 95616
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28
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Eva MM, Yuki KE, Dauphinee SM, Schwartzentruber JA, Pyzik M, Paquet M, Lathrop M, Majewski J, Vidal SM, Malo D. Altered IFN-γ-mediated immunity and transcriptional expression patterns in N-Ethyl-N-nitrosourea-induced STAT4 mutants confer susceptibility to acute typhoid-like disease. THE JOURNAL OF IMMUNOLOGY 2013; 192:259-70. [PMID: 24285835 DOI: 10.4049/jimmunol.1301370] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Salmonella enterica is a ubiquitous Gram-negative intracellular bacterium that continues to pose a global challenge to human health. The etiology of Salmonella pathogenesis is complex and controlled by pathogen, environmental, and host genetic factors. In fact, patients immunodeficient in genes in the IL-12, IL-23/IFN-γ pathway are predisposed to invasive nontyphoidal Salmonella infection. Using a forward genomics approach by N-ethyl-N-nitrosourea (ENU) germline mutagenesis in mice, we identified the Ity14 (Immunity to Typhimurium locus 14) pedigree exhibiting increased susceptibility following in vivo Salmonella challenge. A DNA-binding domain mutation (p.G418_E445) in Stat4 (Signal Transducer and Activator of Transcription Factor 4) was the causative mutation. STAT4 signals downstream of IL-12 to mediate transcriptional regulation of inflammatory immune responses. In mutant Ity14 mice, the increased splenic and hepatic bacterial load resulted from an intrinsic defect in innate cell function, IFN-γ-mediated immunity, and disorganized granuloma formation. We further show that NK and NKT cells play an important role in mediating control of Salmonella in Stat4(Ity14/Ity14) mice. Stat4(Ity14/Ity14) mice had increased expression of genes involved in cell-cell interactions and communication, as well as increased CD11b expression on a subset of splenic myeloid dendritic cells, resulting in compromised recruitment of inflammatory cells to the spleen during Salmonella infection. Stat4(Ity14/Ity14) presented upregulated compensatory mechanisms, although inefficient and ultimately Stat4(Ity14/Ity14) mice develop fatal bacteremia. The following study further elucidates the pathophysiological impact of STAT4 during Salmonella infection.
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Affiliation(s)
- Megan M Eva
- Department of Human Genetics, McGill University, Montreal, Quebec H3G 0B1, Canada
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29
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Melican K, Duménil G. A humanized model of microvascular infection. Future Microbiol 2013; 8:567-9. [PMID: 23642111 DOI: 10.2217/fmb.13.35] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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30
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Leung C, Chijioke O, Gujer C, Chatterjee B, Antsiferova O, Landtwing V, McHugh D, Raykova A, Münz C. Infectious diseases in humanized mice. Eur J Immunol 2013; 43:2246-54. [PMID: 23913412 DOI: 10.1002/eji.201343815] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Revised: 07/23/2013] [Accepted: 07/31/2013] [Indexed: 12/15/2022]
Abstract
Despite many theoretical incompatibilities between mouse and human cells, mice with reconstituted human immune system components contain nearly all human leukocyte populations. Accordingly, several human-tropic pathogens have been investigated in these in vivo models of the human immune system, including viruses such as human immunodeficiency virus (HIV) and Epstein-Barr virus (EBV), as well as bacteria such as Mycobacterium tuberculosis and Salmonella enterica Typhi. While these studies initially aimed to establish similarities in the pathogenesis of infections between these models and the pathobiology in patients, recent investigations have provided new and interesting functional insights into the protective value of certain immune compartments and altered pathology upon mutant pathogen infections. As more tools and methodologies are developed to make these models more versatile to study human immune responses in vivo, such improvements build toward small animal models with human immune components, which could predict immune responses to therapies and vaccination in human patients.
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Affiliation(s)
- Carol Leung
- Department of Viral Immunobiology, Institute of Experimental Immunology, University of Zurich, Zurich, Switzerland
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31
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Brehm MA, Jouvet N, Greiner DL, Shultz LD. Humanized mice for the study of infectious diseases. Curr Opin Immunol 2013; 25:428-35. [PMID: 23751490 DOI: 10.1016/j.coi.2013.05.012] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 05/15/2013] [Accepted: 05/17/2013] [Indexed: 12/17/2022]
Abstract
Many of the pathogens that cause human infectious diseases do not infect rodents or other mammalian species. Small animal models that allow studies of the pathogenesis of these agents and evaluation of drug efficacy are critical for identifying ways to prevent and treat human infectious diseases. Immunodeficient mice engrafted with functional human cells and tissues, termed 'humanized' mice, represent a critical pre-clinical bridge for in vivo studies of human pathogens. Recent advances in the development of humanized mice have allowed in vivo studies of multiple human infectious agents providing novel insights into their pathogenesis that was otherwise not possible.
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Affiliation(s)
- Michael A Brehm
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01655, United States
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32
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Akkina R. Human immune responses and potential for vaccine assessment in humanized mice. Curr Opin Immunol 2013; 25:403-9. [PMID: 23628166 DOI: 10.1016/j.coi.2013.03.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 03/27/2013] [Indexed: 12/13/2022]
Abstract
The new humanized mouse models with a transplanted human immune system have a capacity for de novo multilineage human hematopoiesis and generate T cells, B cells, macrophages, dendritic cells and NK cells. Of the two current leading humanized mouse models, the hu-HSC model is created by human hematopoietic stem cell (HSC) engraftment whereas the BLT mouse model is prepared by co-transplantation of human fetal liver, thymus and HSC. Humoral and cellular immune responses are seen in both models after immunization with antigens or infection with hematotropic pathogens such as EBV, HIV-1 and dengue viruses. While consistent antigen specific IgM production is seen, IgG responses were found to be generally feeble which is attributed to inefficient immunoglobulin class switching. BLT mice permit human HLA restricted T cell responses due to the autologous human thymus contributing to T cell maturation. Use of HLA Class I and II transgenic hu-HSC mice recently demonstrated that the HLA restriction deficiency could be overcome in this model. However, the overall vigor of the immune responses needs further improvement in both the models to approach that of the human. Towards this goal, supplementation with human cytokines and growth factors by transgenesis to improve human cell reconstitution and their homeostatic maintenance are beginning to yield improved mouse strains to create more robust human immune competent mice for immunoprophylaxis studies.
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Affiliation(s)
- Ramesh Akkina
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA.
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33
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Akkina R. New generation humanized mice for virus research: comparative aspects and future prospects. Virology 2013; 435:14-28. [PMID: 23217612 DOI: 10.1016/j.virol.2012.10.007] [Citation(s) in RCA: 150] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Revised: 10/03/2012] [Accepted: 10/03/2012] [Indexed: 12/27/2022]
Abstract
Work with human specific viruses will greatly benefit from the use of an in vivo system that provides human target cells and tissues in a physiological setting. In this regard humanized mice (hu-Mice) have played an important role in our understanding of viral pathogenesis and testing of therapeutic strategies. Limitations with earlier versions of hu-Mice that lacked a functioning human immune system are currently being overcome. The new generation hu-Mouse models are capable of multilineage human hematopoiesis and generate T cells, B cells, macrophages and dendritic cells required for an adaptive human immune response. Now any human specific pathogen that can infect humanized mice can be studied in the context of ongoing infection and immune responses. Two leading humanized mouse models are currently employed: the hu-HSC model is created by transplantation of human hematopoietic stem cells (HSC), whereas the BLT mouse model is prepared by transplantation of human fetal liver, thymus and HSC. A number of human specific viruses such as HIV-1, dengue, EBV and HCV are being studied intensively in these systems. Both models permit infection by mucosal routes with viruses such as HIV-1 thus allowing transmission prevention studies. Cellular and humoral immune responses are seen in both the models. While there is efficient antigen specific IgM production, IgG responses are suboptimal due to inefficient immunoglobulin class switching. With the maturation of T cells occurring in the autologous human thymus, BLT mice permit human HLA restricted T cell responses in contrast to hu-HSC mice. However, the strength of the immune responses needs further improvement in both models to reach the levels seen in humans. The scope of hu-Mice use is further broadened by transplantation of additional tissues like human liver thus permitting immunopathogenesis studies on hepatotropic viruses such as HCV. Numerous studies that encompass antivirals, gene therapy, viral evolution, and the generation of human monoclonal antibodies have been conducted with promising results in these mice. For further improvement of the new hu-Mouse models, ongoing work is focused on generating new strains of immunodeficient mice transgenic for human HLA molecules to strengthen immune responses and human cytokines and growth factors to improve human cell reconstitution and their homeostatic maintenance.
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Affiliation(s)
- Ramesh Akkina
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA.
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34
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Mathur R, Oh H, Zhang D, Park SG, Seo J, Koblansky A, Hayden MS, Ghosh S. A mouse model of Salmonella typhi infection. Cell 2013; 151:590-602. [PMID: 23101627 DOI: 10.1016/j.cell.2012.08.042] [Citation(s) in RCA: 156] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 06/29/2012] [Accepted: 08/15/2012] [Indexed: 01/29/2023]
Abstract
Salmonella spp. are gram-negative flagellated bacteria that can cause food- and waterborne gastroenteritis and typhoid fever in humans. We now report that flagellin from Salmonella spp. is recognized in mouse intestine by Toll-like receptor 11 (TLR11). Absence of TLR11 renders mice more susceptible to infection by S. Typhimurium, with increased dissemination of the bacteria and enhanced lethality. Unlike S. Typhimurium, S. Typhi, a human obligatory pathogen that causes typhoid fever, is normally unable to infect mice. TLR11 is expressed in mice, but not in humans, and remarkably, we find that tlr11(-/-) mice are efficiently infected with orally administered S. Typhi. We also find that tlr11(-/-) mice can be immunized against S. Typhi. Therefore, tlr11(-/-) mice represent a small-animal model for the study of the immune response to S. Typhi and for the development of vaccines against this important human pathogen.
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Affiliation(s)
- Ramkumar Mathur
- Department of Microbiology and Immunology, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA
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35
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New technologies in developing recombinant attenuated Salmonella vaccine vectors. Microb Pathog 2012; 58:17-28. [PMID: 23142647 DOI: 10.1016/j.micpath.2012.10.006] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 10/29/2012] [Accepted: 10/30/2012] [Indexed: 01/01/2023]
Abstract
Recombinant attenuated Salmonella vaccine (RASV) vectors producing recombinant gene-encoded protective antigens should have special traits. These features ensure that the vaccines survive stresses encountered in the gastrointestinal tract following oral vaccination to colonize lymphoid tissues without causing disease symptoms and to result in induction of long-lasting protective immune responses. We recently described ways to achieve these goals by using regulated delayed in vivo attenuation and regulated delayed in vivo antigen synthesis, enabling RASVs to efficiently colonize effector lymphoid tissues and to serve as factories to synthesize protective antigens that induce higher protective immune responses. We also developed some additional new strategies to increase vaccine safety and efficiency. Modification of lipid A can reduce the inflammatory responses without compromising the vaccine efficiency. Outer membrane vesicles (OMVs) from Salmonella-containing heterologous protective antigens can be used to increase vaccine efficiency. A dual-plasmid system, possessing Asd+ and DadB+ selection markers, each specifying a different protective antigen, can be used to develop multivalent live vaccines. These new technologies have been adopted to develop a novel, low-cost RASV synthesizing multiple protective pneumococcal protein antigens that could be safe for newborns/infants and induce protective immunity to diverse Streptococcus pneumoniae serotypes after oral immunization.
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Shultz LD, Brehm MA, Garcia-Martinez JV, Greiner DL. Humanized mice for immune system investigation: progress, promise and challenges. Nat Rev Immunol 2012; 12:786-98. [PMID: 23059428 DOI: 10.1038/nri3311] [Citation(s) in RCA: 722] [Impact Index Per Article: 55.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Significant advances in our understanding of the in vivo functions of human cells and tissues and the human immune system have resulted from the development of 'humanized' mouse strains that are based on severely immunodeficient mice with mutations in the interleukin-2 receptor common γ-chain locus. These mouse strains support the engraftment of a functional human immune system and permit detailed analyses of human immune biology, development and functions. In this Review, we discuss recent advances in the development and utilization of humanized mice, the lessons learnt, the remaining challenges and the promise of using humanized mice for the in vivo study of human immunology.
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Affiliation(s)
- Leonard D Shultz
- Jackson Laboratory, 600 Main Street, Bar Harbor, Maine 04609, USA.
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A germline-competent embryonic stem cell line from NOD.Cg-Prkdc scid Il2rg tm1Wjl /SzJ (NSG) mice. Transgenic Res 2012; 22:179-85. [DOI: 10.1007/s11248-012-9629-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 06/18/2012] [Indexed: 01/22/2023]
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Abstract
Humanized mouse models that have received human cells or tissue transplants are extremely useful in basic and applied human disease research. Highly immunodeficient mice, which do not reject xenografts and support cell and tissue differentiation and growth, are indispensable for generating additional appropriate models. Since the early 2000s, a series of immunodeficient mice appropriate for generating humanized mice has been successively developed by introducing the IL-2Rγ(null) gene (e.g., NOD/SCID/γc(null) and Rag2(null)γc(null) mice). These strains show not only a high rate of human cell engraftment, but also generate well-differentiated multilineage human hematopoietic cells after human hematopoietic stem cell (HSC) transplantation. These humanized mice facilitate the analysis of human hematology and immunology in vivo. However, human hematopoietic cells developed from HSCs are not always phenotypically and functionally identical to those in humans. More recently, a new series of immunodeficient mice compensates for these disadvantages. These mice were generated by genetically introducing human cytokine genes into NOD/SCID/γc(null) and Rag2(null)γc(null) mice. In this review, we describe the current knowledge of human hematopoietic cells developed in these mice. Various human disease mouse models using these humanized mice are summarized.
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Serum antibodies protect against intraperitoneal challenge with enterotoxigenic Escherichia coli. J Biomed Biotechnol 2011; 2011:632396. [PMID: 22007145 PMCID: PMC3191916 DOI: 10.1155/2011/632396] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Revised: 04/27/2011] [Accepted: 06/17/2011] [Indexed: 12/27/2022] Open
Abstract
To assess whether anticolonization factor antigen I (CFA/I) fimbriae antibodies (Abs) from enterotoxigenic Escherichia coli (ETEC) can protect against various routes of challenge, BALB/c mice were immunized with a live attenuated Salmonella vaccine vector expressing CFA/I fimbriae. Vaccinated mice elicited elevated systemic IgG and mucosal IgA Abs, unlike mice immunized with the empty Salmonella vector. Mice were challenged with wild-type ETEC by the oral, intranasal (i.n.), and intraperitoneal (i.p.) routes. Naïve mice did not succumb to oral challenge, but did to i.n. challenge, as did immunized mice; however, vaccinated mice were protected against i.p. ETEC challenge. Two intramuscular (i.m.) immunizations with CFA/I fimbriae without adjuvant conferred 100% protection against i.p. ETEC challenge, while a single 30 μg dose conferred 88% protection. Bactericidal assays showed that ETEC is highly sensitive to anti-CFA/I sera. These results suggest that parenteral immunization with purified CFA/I fimbriae can induce protective Abs and may represent an alternative method to elicit protective Abs for passive immunity to ETEC.
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Improving human hemato-lymphoid-system mice by cytokine knock-in gene replacement. Trends Immunol 2011; 32:321-7. [DOI: 10.1016/j.it.2011.04.005] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 04/14/2011] [Accepted: 04/15/2011] [Indexed: 11/17/2022]
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Denton PW, García JV. Humanized mouse models of HIV infection. AIDS Rev 2011; 13:135-148. [PMID: 21799532 PMCID: PMC3741405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Because of the limited tropism of HIV, in vivo modeling of this virus has been almost exclusively limited to other lentiviruses, such as simian immunodeficiency virus, that reproduce many important characteristics of HIV infection. However, there are significant genetic and biological differences among lentiviruses and some HIV-specific interventions are not effective against other lentiviruses in nonhuman hosts. For these reasons, much emphasis has recently been placed on developing alternative animal models that support HIV replication and recapitulate key aspects of HIV infection and pathogenesis in humans. Humanized mice, CD34+ hematopoietic progenitor cell transplanted immunodeficient mice, and in particular mice also implanted with human thymus/liver tissue (bone marrow liver thymus mice) that develop a functional human immune system, have been the focus of a great deal of attention as possible models to study virtually all aspects of HIV biology and pathogenesis. Humanized mice are systemically reconstituted with human lymphoid cells, offering rapid, reliable, and reproducible experimental systems for HIV research. Peripheral blood of humanized mice can be readily sampled longitudinally to assess reconstitution with human cells and to monitor HIV replication, permitting the evaluation of multiple parameters of HIV infection such as viral load levels, CD4+ T-cell depletion, immune activation, as well as the effects of therapeutic interventions. Of high relevance to HIV transmission is the extensive characterization and validation of the reconstitution with human lymphoid cells of the female reproductive tract and of the gastrointestinal tract of humanized bone marrow liver thymus mice that renders them susceptible to both vaginal and rectal HIV infection. Other important attributes of all types of humanized mice include: (i) their small size and cost that make them widely accessible; (ii) multiple cohorts of humanized mice can be made from multiple human donors and each cohort has identical human cells, permitting control of intragenetic variables; (iii) continuous de novo production of human immune cells from the transplanted CD34+ cells within each humanized mouse facilitates long-term experiments; (iv) both primary and laboratory HIV isolates can be used for experiments; and (v) in addition to therapeutic interventions, rectal and vaginal HIV prevention approaches can be studied. In summary, humanized mice can have an important role in virtually all aspects of HIV research, including the analysis of HIV replication, the evaluation of HIV restriction factors, the characterization of successful biomedical HIV prevention strategies, the evaluation of new treatment regimens, and the evaluation of novel HIV eradication strategies.
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Affiliation(s)
- Paul W Denton
- Division of Infectious Diseases, UNC Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, USA.
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Karavolos MH, Williams P, Khan CMA. Interkingdom crosstalk: host neuroendocrine stress hormones drive the hemolytic behavior of Salmonella typhi. Virulence 2011; 2:371-4. [PMID: 21758008 PMCID: PMC3173680 DOI: 10.4161/viru.2.4.16810] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2011] [Revised: 06/24/2011] [Accepted: 06/28/2011] [Indexed: 11/19/2022] Open
Abstract
The ability of bacterial pathogens to sense their immediate environment plays a significant role on their capacity to survive and cause disease. Salmonella enterica serovar typhi (S. typhi) is an exclusively human pathogen that causes typhoid fever. In a recent study, we have shown that S. typhi senses and responds to host neuroendocrine stress hormones to release the toxin hemolysin E. Hormone-mediated hemolysis by S. typhi was inhibited by the β-blocker propranolol and was dependent on the presence of the CpxAR signal transduction system. Furthermore, we demonstrate that normal expression of the small RNA micA is necessary for the arbitration of the response to host neuroendocrine hormones. This leads to a significant decrease in the levels of the outer membrane protein OmpA and increased formation of membrane vesicles containing HlyE. The exploration of host pathogen interactions is of paramount importance in deciphering pathogen virulence and the discovery of novel treatments.
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Affiliation(s)
- Michail H Karavolos
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle, UK.
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Ahmer BMM, Gunn JS. Interaction of Salmonella spp. with the Intestinal Microbiota. Front Microbiol 2011; 2:101. [PMID: 21772831 PMCID: PMC3131049 DOI: 10.3389/fmicb.2011.00101] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 04/25/2011] [Indexed: 12/20/2022] Open
Abstract
Salmonella spp. are major cause of human morbidity and mortality worldwide. Upon entry into the human host, Salmonella spp. must overcome the resistance to colonization mediated by the gut microbiota and the innate immune system. They successfully accomplish this by inducing inflammation and mechanisms of innate immune defense. Many models have been developed to study Salmonella spp. interaction with the microbiota that have helped to identify factors necessary to overcome colonization resistance and to mediate disease. Here we review the current state of studies into this important pathogen/microbiota/host interaction in the mammalian gastrointestinal tract.
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Affiliation(s)
- Brian M M Ahmer
- The Department of Microbiology, The Ohio State University Columbus, OH, USA
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