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Tkaczyk C, Newton M, Patnaik MM, Thom G, Strain M, Gamson A, Daramola O, Murthy A, Douthwaite J, Stepanov O, Boger E, Yang H, Esser MT, Lidwell A, DiGiandomenico A, Santos L, Sellman BR. In vivo mRNA expression of a multi-mechanistic mAb combination protects against Staphylococcus aureus infection. Mol Ther 2024:S1525-0016(24)00338-1. [PMID: 38822525 DOI: 10.1016/j.ymthe.2024.05.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 04/30/2024] [Accepted: 05/29/2024] [Indexed: 06/03/2024] Open
Abstract
Single monoclonal antibodies (mAbs) can be expressed in vivo through gene delivery of their mRNA formulated with lipid nanoparticles (LNPs). However, delivery of a mAb combination could be challenging due to the risk of heavy and light variable chain mispairing. We evaluated the pharmacokinetics of a three mAb combination against Staphylococcus aureus first in single chain variable fragment scFv-Fc and then in immunoglobulin G 1 (IgG1) format in mice. Intravenous delivery of each mRNA/LNP or the trio (1 mg/kg each) induced functional antibody expression after 24 h (10-100 μg/mL) with 64%-78% cognate-chain paired IgG expression after 3 days, and an absence of non-cognate chain pairing for scFv-Fc. We did not observe reduced neutralizing activity for each mAb compared with the level of expression of chain-paired mAbs. Delivery of the trio mRNA protected mice in an S. aureus-induced dermonecrosis model. Intravenous administration of the three mRNA in non-human primates achieved peak serum IgG levels ranging between 2.9 and 13.7 μg/mL with a half-life of 11.8-15.4 days. These results suggest nucleic acid delivery of mAb combinations holds promise and may be a viable option to streamline the development of therapeutic antibodies.
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Affiliation(s)
- Christine Tkaczyk
- AstraZeneca, Early Vaccines & Immune Therapies, Gaithersburg, MD 20878, USA.
| | - Michael Newton
- AstraZeneca, BioPharmaceutical Development, BioPharmaceuticals R&D, Gaithersburg, MD 20878, USA
| | - Mun Mun Patnaik
- AstraZeneca, Early Vaccines & Immune Therapies, Gaithersburg, MD 20878, USA
| | - George Thom
- AstraZeneca, Discovery Sciences, BioPharmaceuticals R&D, Cambridge CB21 6GH, UK
| | - Martin Strain
- AstraZeneca, Biologics Engineering, BioPharmaceuticals R&D, Cambridge CB216GH, UK
| | - Adam Gamson
- AstraZeneca, Early Vaccines & Immune Therapies, Gaithersburg, MD 20878, USA
| | - Olalekan Daramola
- AstraZeneca, BioPharmaceutical Development, BioPharmaceuticals R&D, Cambridge CB21 6GH, UK
| | - Andal Murthy
- AstraZeneca, BioPharmaceutical Development, BioPharmaceuticals R&D, Cambridge CB21 6GH, UK
| | - Julie Douthwaite
- AstraZeneca, Discovery Sciences, BioPharmaceuticals R&D, Cambridge CB21 6GH, UK
| | - Oleg Stepanov
- Clinical Pharmacology and Pharmacometrics, BioPharmaceuticals R&D, AstraZeneca, Cambridge CB2 8PA, UK
| | - Elin Boger
- Drug Metabolism and Pharmacokinetics, Research and Early Development, Respirator & immunology, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Haitao Yang
- Clinical Pharmacology and Pharmacometrics, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD 20878, USA
| | - Mark T Esser
- AstraZeneca, Early Vaccines & Immune Therapies, Gaithersburg, MD 20878, USA
| | - Ashley Lidwell
- AstraZeneca, Early Vaccines & Immune Therapies, Gaithersburg, MD 20878, USA
| | | | - Luis Santos
- AstraZeneca, BioPharmaceutical Development, BioPharmaceuticals R&D, Gaithersburg, MD 20878, USA
| | - Bret R Sellman
- AstraZeneca, Early Vaccines & Immune Therapies, Gaithersburg, MD 20878, USA
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Bratkovič T, Zahirović A, Bizjak M, Rupnik M, Štrukelj B, Berlec A. New treatment approaches for Clostridioides difficile infections: alternatives to antibiotics and fecal microbiota transplantation. Gut Microbes 2024; 16:2337312. [PMID: 38591915 PMCID: PMC11005816 DOI: 10.1080/19490976.2024.2337312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 03/27/2024] [Indexed: 04/10/2024] Open
Abstract
Clostridioides difficile causes a range of debilitating intestinal symptoms that may be fatal. It is particularly problematic as a hospital-acquired infection, causing significant costs to the health care system. Antibiotics, such as vancomycin and fidaxomicin, are still the drugs of choice for C. difficile infections, but their effectiveness is limited, and microbial interventions are emerging as a new treatment option. This paper focuses on alternative treatment approaches, which are currently in various stages of development and can be divided into four therapeutic strategies. Direct killing of C. difficile (i) includes beside established antibiotics, less studied bacteriophages, and their derivatives, such as endolysins and tailocins. Restoration of microbiota composition and function (ii) is achieved with fecal microbiota transplantation, which has recently been approved, with standardized defined microbial mixtures, and with probiotics, which have been administered with moderate success. Prevention of deleterious effects of antibiotics on microbiota is achieved with agents for the neutralization of antibiotics that act in the gut and are nearing regulatory approval. Neutralization of C. difficile toxins (iii) which are crucial virulence factors is achieved with antibodies/antibody fragments or alternative binding proteins. Of these, the monoclonal antibody bezlotoxumab is already in clinical use. Immunomodulation (iv) can help eliminate or prevent C. difficile infection by interfering with cytokine signaling. Small-molecule agents without bacteriolytic activity are usually selected by drug repurposing and can act via a variety of mechanisms. The multiple treatment options described in this article provide optimism for the future treatment of C. difficile infection.
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Affiliation(s)
- Tomaž Bratkovič
- Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
| | - Abida Zahirović
- Department of Biotechnology, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Maruša Bizjak
- Department of Biotechnology, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Maja Rupnik
- National Laboratory for Health, Environment and Food, Prvomajska 1, Maribor, Slovenia
- Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | - Borut Štrukelj
- Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
- Department of Biotechnology, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Aleš Berlec
- Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
- Department of Biotechnology, Jožef Stefan Institute, Ljubljana, Slovenia
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3
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Sun Y, Zhang Y, Yu H, Saint Fleur A, Yu D, Yang Z, Feng H. A fine-tuned yeast surface-display/secretion platform enables the rapid discovery of neutralizing antibodies against Clostridioides difficile toxins. Microb Cell Fact 2023; 22:194. [PMID: 37749574 PMCID: PMC10519002 DOI: 10.1186/s12934-023-02200-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 09/06/2023] [Indexed: 09/27/2023] Open
Abstract
BACKGROUND Neutralizing antibody plays a key role in protecting hosts from invasive pathogens and their virulent components. Current high-throughput assays for antibody screening are based on binding activities. However, those antibodies with high affinity may not have neutralizing activities. Subsequent functionality assays are necessary to identify neutralizing antibodies from binders with high affinity to their target antigens, which is laborious and time-consuming. Therefore, a versatile platform that can rapidly identify antibodies with both high binding affinity and neutralizing activity is desired to curb future pandemics like COVID-19. RESULTS In this proof-of-concept study, we adapted Saccharomyces cerevisiae to either display human antibodies on the yeast surface or secrete soluble antibodies into the cultivation supernatant under a controllable 'switch' through different carbon source induced promoters. Initially, an engineered chimeric-bispecific Fab antibody, derived from humanized nanobodies against both Clostridioides difficile toxin A and B (TcdA and TcdB), was successfully expressed either on the yeast cell surface or in the culture medium with intact bioactivity, suggesting the applicability of our system in antibody display and secretion. Next, a combinatorial Fab library was constructed from B cells isolated from a convalescent patient with a high serological neutralizing titer against TcdB. Following three rounds of magnetic bead enrichment and one round of flow cytometry sorting, antibodies against TcdB were enriched efficiently. We then sorted out single binders with high binding affinity and induced them to express soluble antibodies in culture medium. The neutralizing activity of culture supernatant was analyzed using cell-based assay immediately. This way, we rapidly identified two unique neutralizers (out of seven binders) that can neutralize the cytotoxicity of TcdB. CONCLUSION The antibody screening platform described here simplifies the neutralizing antibody discovery procedure and will be an attractive alternative for screening functional antibodies against infectious diseases.
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Affiliation(s)
- Ying Sun
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD, 21201, USA.
- Department of Pathogen Biology, School of Basic Medical Sciences, China Medical University, Shenyang, 110122, China.
| | - Yongrong Zhang
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD, 21201, USA
| | - Hua Yu
- Fzata, Inc, Halethorpe, MD, 21227, USA
| | - Ashley Saint Fleur
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD, 21201, USA
| | - Di Yu
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD, 21201, USA
| | | | - Hanping Feng
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD, 21201, USA.
- Fzata, Inc, Halethorpe, MD, 21227, USA.
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Yu S, Zhang L, Wang A, Jin Y, Zhou D. Nanobodies: the Potential Application in Bacterial Treatment and Diagnosis. Biochem Pharmacol 2023:115640. [PMID: 37315818 DOI: 10.1016/j.bcp.2023.115640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 06/02/2023] [Accepted: 06/06/2023] [Indexed: 06/16/2023]
Abstract
An infection caused by bacteria is one of the main factors that poses a threat to human health. A recent report from the World Health Organization (WHO) has highlighted that bacteria that cause blood infections have become increasingly drug-resistant. Therefore, it is crucial to research and develop new techniques for detecting and treating these infections. Since their discovery, nanobodies have exhibited numerous outstanding biological properties. They are easy to express, modify, and have high stability, robust permeability and low immunogenicity, all of which indicate their potential as a substitute. Nanobodies have been utilized in a variety of studies on viruses and cancer. This article primarily focuses on nanobodies and introduces their characteristics and application in the diagnosis and treatment of bacterial infections.
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Affiliation(s)
- Siyuan Yu
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture and Rural Affairs, Northwest A&F University, Xianyang, China
| | - Lu Zhang
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture and Rural Affairs, Northwest A&F University, Xianyang, China; Northwest A&F University Shenzhen Research Institute, Shenzhen, China; Department of Animal Engineering, Yangling Vocational&Technical College, Xianyang, China
| | - Aihua Wang
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture and Rural Affairs, Northwest A&F University, Xianyang, China
| | - Yaping Jin
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture and Rural Affairs, Northwest A&F University, Xianyang, China; Northwest A&F University Shenzhen Research Institute, Shenzhen, China.
| | - Dong Zhou
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture and Rural Affairs, Northwest A&F University, Xianyang, China
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Chen B, Perry K, Jin R. Neutralizing epitopes on Clostridioides difficile toxin A revealed by the structures of two camelid VHH antibodies. Front Immunol 2022; 13:978858. [PMID: 36466927 PMCID: PMC9709291 DOI: 10.3389/fimmu.2022.978858] [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: 06/26/2022] [Accepted: 10/31/2022] [Indexed: 11/18/2022] Open
Abstract
Toxin A (TcdA) and toxin B (TcdB) are two key virulence factors secreted by Clostridioides difficile, which is listed as an urgent threat by the CDC. These two large homologous exotoxins are mainly responsible for diseases associated with C. difficile infection (CDI) with symptoms ranging from diarrhea to life threatening pseudomembranous colitis. Single-domain camelid antibodies (VHHs) AH3 and AA6 are two potent antitoxins against TcdA, which when combined with two TcdB-targeting VHHs showed effective protection against both primary and recurrent CDI in animal models. Here, we report the co-crystal structures of AH3 and AA6 when they form complexes with the glucosyltransferase domain (GTD) and a fragment of the delivery and receptor-binding domain (DRBD) of TcdA, respectively. Based on these structures, we find that AH3 binding enhances the overall stability of the GTD and interferes with its unfolding at acidic pH, and AA6 may inhibit the pH-dependent conformational changes in the DRBD that is necessary for pore formation of TcdA. These studies reveal two functionally critical epitopes on TcdA and shed new insights into neutralizing mechanisms and potential development of epitope-focused vaccines against TcdA.
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Affiliation(s)
- Baohua Chen
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, United States
| | - Kay Perry
- NE-CAT, Advanced Photon Source, Argonne National Laboratory, Argonne, IL, United States,Department of Chemistry and Chemical Biology, Cornell University, Argonne, IL, United States
| | - Rongsheng Jin
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, United States,*Correspondence: Rongsheng Jin,
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Qin Q, Liu H, He W, Guo Y, Zhang J, She J, Zheng F, Zhang S, Muyldermans S, Wen Y. Single Domain Antibody application in bacterial infection diagnosis and neutralization. Front Immunol 2022; 13:1014377. [PMID: 36248787 PMCID: PMC9558170 DOI: 10.3389/fimmu.2022.1014377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 09/15/2022] [Indexed: 11/21/2022] Open
Abstract
Increasing antibiotic resistance to bacterial infections causes a serious threat to human health. Efficient detection and treatment strategies are the keys to preventing and reducing bacterial infections. Due to the high affinity and antigen specificity, antibodies have become an important tool for diagnosis and treatment of various human diseases. In addition to conventional antibodies, a unique class of “heavy-chain-only” antibodies (HCAbs) were found in the serum of camelids and sharks. HCAbs binds to the antigen through only one variable domain Referred to as VHH (variable domain of the heavy chain of HCAbs). The recombinant format of the VHH is also called single domain antibody (sdAb) or nanobody (Nb). Sharks might also have an ancestor HCAb from where SdAbs or V-NAR might be engineered. Compared with traditional Abs, Nbs have several outstanding properties such as small size, high stability, strong antigen-binding affinity, high solubility and low immunogenicity. Furthermore, they are expressed at low cost in microorganisms and amenable to engineering. These superior properties make Nbs a highly desired alternative to conventional antibodies, which are extensively employed in structural biology, unravelling biochemical mechanisms, molecular imaging, diagnosis and treatment of diseases. In this review, we summarized recent progress of nanobody-based approaches in diagnosis and neutralization of bacterial infection and further discussed the challenges of Nbs in these fields.
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Affiliation(s)
- Qian Qin
- Department of General Surgery, Center for Microbiome Research of Med-X Institute, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
- The Key Laboratory of Environment and Genes Related to Disease of Ministry of Education, Health Science Center, Xi'an Jiaotong University, Xi'an, China
| | - Hao Liu
- Center for Biomedical Research, Institute of Future Agriculture, Northwest A&F University, Yangling, China
| | - Wenbo He
- Department of General Surgery, Center for Microbiome Research of Med-X Institute, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Yucheng Guo
- The Key Laboratory of Environment and Genes Related to Disease of Ministry of Education, Health Science Center, Xi'an Jiaotong University, Xi'an, China
| | - Jiaxin Zhang
- The Key Laboratory of Environment and Genes Related to Disease of Ministry of Education, Health Science Center, Xi'an Jiaotong University, Xi'an, China
| | - Junjun She
- Department of General Surgery, Center for Microbiome Research of Med-X Institute, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Fang Zheng
- The Key Laboratory of Environment and Genes Related to Disease of Ministry of Education, Health Science Center, Xi'an Jiaotong University, Xi'an, China
| | - Sicai Zhang
- Center for Biomedical Research, Institute of Future Agriculture, Northwest A&F University, Yangling, China
| | - Serge Muyldermans
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Yurong Wen
- Department of General Surgery, Center for Microbiome Research of Med-X Institute, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
- The Key Laboratory of Environment and Genes Related to Disease of Ministry of Education, Health Science Center, Xi'an Jiaotong University, Xi'an, China
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7
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Raeisi H, Azimirad M, Nabavi-Rad A, Asadzadeh Aghdaei H, Yadegar A, Zali MR. Application of recombinant antibodies for treatment of Clostridioides difficile infection: Current status and future perspective. Front Immunol 2022; 13:972930. [PMID: 36081500 PMCID: PMC9445313 DOI: 10.3389/fimmu.2022.972930] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 08/03/2022] [Indexed: 11/13/2022] Open
Abstract
Clostridioides difficile (C. difficile), known as the major cause of antibiotic-associated diarrhea, is regarded as one of the most common healthcare-associated bacterial infections worldwide. Due to the emergence of hypervirulent strains, development of new therapeutic methods for C. difficile infection (CDI) has become crucially important. In this context, antibodies have been introduced as valuable tools in the research and clinical environments, as far as the effectiveness of antibody therapy for CDI was reported in several clinical investigations. Hence, production of high-performance antibodies for treatment of CDI would be precious. Traditional approaches of antibody generation are based on hybridoma technology. Today, application of in vitro technologies for generating recombinant antibodies, like phage display, is considered as an appropriate alternative to hybridoma technology. These techniques can circumvent the limitations of the immune system and they can be exploited for production of antibodies against different types of biomolecules in particular active toxins. Additionally, DNA encoding antibodies is directly accessible in in vitro technologies, which enables the application of antibody engineering in order to increase their sensitivity and specificity. Here, we review the application of antibodies for CDI treatment with an emphasis on recombinant fragment antibodies. Also, this review highlights the current and future prospects of the aforementioned approaches for antibody-mediated therapy of CDI.
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Affiliation(s)
- Hamideh Raeisi
- Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Masoumeh Azimirad
- Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ali Nabavi-Rad
- Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hamid Asadzadeh Aghdaei
- Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abbas Yadegar
- Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- *Correspondence: Abbas Yadegar, ;
| | - Mohammad Reza Zali
- Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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8
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Chen K, Zhu Y, Zhang Y, Hamza T, Yu H, Saint Fleur A, Galen J, Yang Z, Feng H. A probiotic yeast-based immunotherapy against Clostridioides difficile infection. Sci Transl Med 2021; 12:12/567/eaax4905. [PMID: 33115949 DOI: 10.1126/scitranslmed.aax4905] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 02/12/2020] [Accepted: 10/07/2020] [Indexed: 12/12/2022]
Abstract
Antibiotic-resistant Clostridioides difficile is an anaerobic Gram-positive bacterium that colonizes the colon and is responsible for more than 29,000 deaths in the United States each year. Hence, C. difficile infection (CDI) poses an urgent threat to public health. Antibody-mediated neutralization of TcdA and TcdB toxins, the major virulence factors of CDI, represents an effective strategy to combat the disease without invoking antibiotic resistance. However, current antitoxin approaches are mostly based on parenteral infusion of monoclonal antibodies that are costly, narrow spectrum, and not optimized against the intestinal disease. Here, we engineered probiotic Saccharomyces boulardii to constitutively secrete a single tetra-specific antibody that potently and broadly neutralized both toxins and demonstrated protection against primary and recurrent CDI in both prophylactic and therapeutic mouse models of disease. This yeast immunotherapy is orally administered, can be used concurrently with antibiotics, and may have potential as a prophylactic against CDI risk and as a therapeutic for patients with CDI.
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Affiliation(s)
- Kevin Chen
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - Yixuan Zhu
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Yongrong Zhang
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - Therwa Hamza
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - Hua Yu
- FZata Inc., Halethorpe, MD 21227, USA
| | - Ashley Saint Fleur
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - James Galen
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | | | - Hanping Feng
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA.
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9
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Chlamydia trachomatis induces autophagy by p62 in HeLa cell. World J Microbiol Biotechnol 2021; 37:50. [PMID: 33590353 DOI: 10.1007/s11274-021-03014-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 01/28/2021] [Indexed: 10/22/2022]
Abstract
Chlamydia trachomatis is the most common bacterial pathogen causing sexually transmitted diseases. C. trachomatis infection is closely related to the development of cervical cancer, studies have shown that C. trachomatis can induce host cell autophagy. The autophagy related gene p62 plays an important role in the process of autophagy. To further understand the role of autophagy-associated gene p62 in autophagy of HeLa cells induced by C. trachomatis, p62-silencing cell line, HeLa229-shp62, and control cell line, HeLa229-shNC, were constructed, and a C. trachomatis-infected cell model was established. The autophagosome and C. trachomatis inclusions were observed under electron microscope. The autophagy level of C. trachomatis-infected HeLa cells was detected by Western blot. The results suggested that knockdown of p62 affected neither C. trachomatis infection of HeLa cells nor the initiation of C. trachomatis-induced autophagy, but at 48 h post C. trachomatis infection, autophagy levels were significantly inhibited in p62 silencing host cells. The study demonstrated the important role of p62 in the autophagy induced by C. trachomatis in HeLa cells, which could provide data support and theoretical basis for exploring the pathogenesis and prevention of C. trachomatis.
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10
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Silva-Pilipich N, Martisova E, Ballesteros-Briones MC, Hervas-Stubbs S, Casares N, González-Sapienza G, Smerdou C, Vanrell L. Long-Term Systemic Expression of a Novel PD-1 Blocking Nanobody from an AAV Vector Provides Antitumor Activity without Toxicity. Biomedicines 2020; 8:biomedicines8120562. [PMID: 33276580 PMCID: PMC7761623 DOI: 10.3390/biomedicines8120562] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 11/24/2020] [Accepted: 11/30/2020] [Indexed: 02/06/2023] Open
Abstract
Immune checkpoint blockade using monoclonal antibodies (mAbs) able to block programmed death-1 (PD-1)/PD-L1 axis represents a promising treatment for cancer. However, it requires repetitive systemic administration of high mAbs doses, often leading to adverse effects. We generated a novel nanobody against PD-1 (Nb11) able to block PD-1/PD-L1 interaction for both mouse and human molecules. Nb11 was cloned into an adeno-associated virus (AAV) vector downstream of four different promoters (CMV, CAG, EF1α, and SFFV) and its expression was analyzed in cells from rodent (BHK) and human origin (Huh-7). Nb11 was expressed at high levels in vitro reaching 2–20 micrograms/mL with all promoters, except SFFV, which showed lower levels. Nb11 in vivo expression was evaluated in C57BL/6 mice after intravenous administration of AAV8 vectors. Nb11 serum levels increased steadily along time, reaching 1–3 microgram/mL two months post-treatment with the vector having the CAG promoter (AAV-CAG-Nb11), without evidence of toxicity. To test the antitumor potential of this vector, mice that received AAV-CAG-Nb11, or saline as control, were challenged with colon adenocarcinoma cells (MC38). AAV-CAG-Nb11 treatment prevented tumor formation in 30% of mice, significantly increasing survival. These data suggest that continuous expression of immunomodulatory nanobodies from long-term expression vectors could have antitumor effects with low toxicity.
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Affiliation(s)
- Noelia Silva-Pilipich
- Division of Gene Therapy and Regulation of Gene Expression, Cima Universidad de Navarra, 31008 Pamplona, Spain; (N.S.-P.); (E.M.); (M.C.B.-B.)
- Instituto de Investigación Sanitaria de Navarra (IdISNA), 31008 Pamplona, Spain; (S.H.-S.); (N.C.)
- Cátedra de Inmunología, DEPBIO, Facultad de Química, Instituto de Higiene, UDELAR, 11600 Montevideo, Uruguay;
| | - Eva Martisova
- Division of Gene Therapy and Regulation of Gene Expression, Cima Universidad de Navarra, 31008 Pamplona, Spain; (N.S.-P.); (E.M.); (M.C.B.-B.)
- Instituto de Investigación Sanitaria de Navarra (IdISNA), 31008 Pamplona, Spain; (S.H.-S.); (N.C.)
| | - María Cristina Ballesteros-Briones
- Division of Gene Therapy and Regulation of Gene Expression, Cima Universidad de Navarra, 31008 Pamplona, Spain; (N.S.-P.); (E.M.); (M.C.B.-B.)
- Instituto de Investigación Sanitaria de Navarra (IdISNA), 31008 Pamplona, Spain; (S.H.-S.); (N.C.)
| | - Sandra Hervas-Stubbs
- Instituto de Investigación Sanitaria de Navarra (IdISNA), 31008 Pamplona, Spain; (S.H.-S.); (N.C.)
- Division of Immunology and Immunotherapy, Cima Universidad de Navarra, 31008 Pamplona, Spain
- CIBERehd, Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Noelia Casares
- Instituto de Investigación Sanitaria de Navarra (IdISNA), 31008 Pamplona, Spain; (S.H.-S.); (N.C.)
- Division of Immunology and Immunotherapy, Cima Universidad de Navarra, 31008 Pamplona, Spain
| | - Gualberto González-Sapienza
- Cátedra de Inmunología, DEPBIO, Facultad de Química, Instituto de Higiene, UDELAR, 11600 Montevideo, Uruguay;
| | - Cristian Smerdou
- Division of Gene Therapy and Regulation of Gene Expression, Cima Universidad de Navarra, 31008 Pamplona, Spain; (N.S.-P.); (E.M.); (M.C.B.-B.)
- Instituto de Investigación Sanitaria de Navarra (IdISNA), 31008 Pamplona, Spain; (S.H.-S.); (N.C.)
- Correspondence: (C.S.); (L.V.); Tel.: +34-948194700 (C.S.); +598-29021505 (L.V.)
| | - Lucia Vanrell
- Cátedra de Inmunología, DEPBIO, Facultad de Química, Instituto de Higiene, UDELAR, 11600 Montevideo, Uruguay;
- Facultad de Ingeniería, Universidad ORT, 11100 Montevideo, Uruguay
- Correspondence: (C.S.); (L.V.); Tel.: +34-948194700 (C.S.); +598-29021505 (L.V.)
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11
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Hussack G, Ryan S, van Faassen H, Rossotti M, MacKenzie CR, Tanha J. Neutralization of Clostridium difficile toxin B with VHH-Fc fusions targeting the delivery and CROPs domains. PLoS One 2018; 13:e0208978. [PMID: 30540857 PMCID: PMC6291252 DOI: 10.1371/journal.pone.0208978] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Accepted: 11/28/2018] [Indexed: 02/08/2023] Open
Abstract
An increasing number of antibody-based therapies are being considered for controlling bacterial infections, including Clostridium difficile by targeting toxins A and B. In an effort to develop novel C. difficile immunotherapeutics, we previously isolated several single-domain antibodies (VHHs) capable of toxin A neutralization through recognition of the extreme C-terminal combined repetitive oligopeptides (CROPs) domain, but failed at identifying neutralizing VHHs that bound a similar region on toxin B. Here we report the isolation of a panel of 29 VHHs targeting at least seven unique epitopes on a toxin B immunogen composed of a portion of the central delivery domain and the entire CROPs domain. Despite monovalent affinities as high as KD = 70 pM, none of the VHHs tested were capable of toxin B neutralization; however, modest toxin B inhibition was observed with VHH-VHH dimers and to a much greater extent with VHH-Fc fusions, reaching the neutralizing potency of the recently approved anti-toxin B monoclonal antibody bezlotoxumab in in vitro assays. Epitope binning revealed that several VHH-Fcs bound toxin B at sites distinct from the region recognized by bezlotoxumab, while other VHH-Fcs partially competed with bezlotoxumab for toxin binding. Therefore, the VHHs described here are effective at toxin B neutralization when formatted as bivalent VHH-Fc fusions by targeting toxin B at regions both similar and distinct from the bezlotoxumab binding site.
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Affiliation(s)
- Greg Hussack
- Human Health Therapeutics Research Centre, National Research Council Canada, Ottawa, Ontario, Canada
- * E-mail:
| | - Shannon Ryan
- Human Health Therapeutics Research Centre, National Research Council Canada, Ottawa, Ontario, Canada
| | - Henk van Faassen
- Human Health Therapeutics Research Centre, National Research Council Canada, Ottawa, Ontario, Canada
| | - Martin Rossotti
- Human Health Therapeutics Research Centre, National Research Council Canada, Ottawa, Ontario, Canada
| | - C. Roger MacKenzie
- Human Health Therapeutics Research Centre, National Research Council Canada, Ottawa, Ontario, Canada
| | - Jamshid Tanha
- Human Health Therapeutics Research Centre, National Research Council Canada, Ottawa, Ontario, Canada
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
- School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada
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12
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Förster B, Chung PK, Crobach MJT, Kuijper EJ. Application of Antibody-Mediated Therapy for Treatment and Prevention of Clostridium difficile Infection. Front Microbiol 2018; 9:1382. [PMID: 29988597 PMCID: PMC6027166 DOI: 10.3389/fmicb.2018.01382] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 06/06/2018] [Indexed: 12/17/2022] Open
Abstract
Clostridium difficile causes antibiotic- and healthcare-associated diarrhea, which is characterized by a high mortality rate (5–15%) and high recurrence rate of 20% or more. Therapeutic alternatives to antibiotics are urgently needed to improve the overall cure rate. Among these, therapeutic antibodies have shown promising results in clinical studies. Herein, the authors review current monoclonal and polyclonal anti- C. difficile antibodies that have entered the clinical development stage, either for systemic administration or by the oral route. The antibodies can be applied as monotherapy or in combination with standard-of-care to treat an infection with C. difficile or to protect from a recurrence. Bezlotoxumab is the first antibody for secondary prevention of recurrence of C. difficile infection approved by the regulatory agencies in US and Europe. The human monoclonal antibody is administered systemically to patients receiving oral standard-of–care antibiotics. Other antibodies are currently in the clinical pipeline, and some are intended for oral use. They show a good safety profile, high efficacy and low production costs, and can be considered promising therapies of the future. The most promising orally administered drug candidate is a bovine antibody from hyperimmune colostral milk, which is in an advanced clinical development stage. Which antibody will enter the market is dependent on its bioavailability at the site of infection as well as its activity against C. difficile toxins, protection against colonization and possible action on spore formation. The antibody must demonstrate a clear benefit in comparison with other available treatment options to be considered for use by clinicians.
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Affiliation(s)
- Beatrix Förster
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands.,Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, Netherlands
| | - Pui Khi Chung
- Department of Medical Microbiology, Centre for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Monique J T Crobach
- Department of Medical Microbiology, Centre for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Ed J Kuijper
- Department of Medical Microbiology, Centre for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
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13
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Kroh HK, Chandrasekaran R, Zhang Z, Rosenthal K, Woods R, Jin X, Nyborg AC, Rainey GJ, Warrener P, Melnyk RA, Spiller BW, Lacy DB. A neutralizing antibody that blocks delivery of the enzymatic cargo of Clostridium difficile toxin TcdB into host cells. J Biol Chem 2017; 293:941-952. [PMID: 29180448 DOI: 10.1074/jbc.m117.813428] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/08/2017] [Indexed: 12/14/2022] Open
Abstract
Clostridium difficile infection is the leading cause of hospital-acquired diarrhea and is mediated by the actions of two toxins, TcdA and TcdB. The toxins perturb host cell function through a multistep process of receptor binding, endocytosis, low pH-induced pore formation, and the translocation and delivery of an N-terminal glucosyltransferase domain that inactivates host GTPases. Infection studies with isogenic strains having defined toxin deletions have established TcdB as an important target for therapeutic development. Monoclonal antibodies that neutralize TcdB function have been shown to protect against C. difficile infection in animal models and reduce recurrence in humans. Here, we report the mechanism of TcdB neutralization by PA41, a humanized monoclonal antibody capable of neutralizing TcdB from a diverse array of C. difficile strains. Through a combination of structural, biochemical, and cell functional studies, involving X-ray crystallography and EM, we show that PA41 recognizes a single, highly conserved epitope on the TcdB glucosyltransferase domain and blocks productive translocation and delivery of the enzymatic cargo into the host cell. Our study reveals a unique mechanism of C. difficile toxin neutralization by a monoclonal antibody, which involves targeting a process that is conserved across the large clostridial glucosylating toxins. The PA41 antibody described here provides a valuable tool for dissecting the mechanism of toxin pore formation and translocation across the endosomal membrane.
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Affiliation(s)
- Heather K Kroh
- From the Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2363
| | - Ramyavardhanee Chandrasekaran
- From the Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2363
| | - Zhifen Zhang
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada.,Molecular Structure and Function, The Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
| | | | - Rob Woods
- MedImmune LLC, Gaithersburg, Maryland 20878-2204
| | - Xiaofang Jin
- MedImmune LLC, Gaithersburg, Maryland 20878-2204
| | | | | | | | - Roman A Melnyk
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada.,Molecular Structure and Function, The Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
| | - Benjamin W Spiller
- From the Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2363.,Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232-6600, and
| | - D Borden Lacy
- From the Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2363, .,Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee 37212-2637
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14
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Kroh HK, Chandrasekaran R, Rosenthal K, Woods R, Jin X, Ohi MD, Nyborg AC, Rainey GJ, Warrener P, Spiller BW, Lacy DB. Use of a neutralizing antibody helps identify structural features critical for binding of Clostridium difficile toxin TcdA to the host cell surface. J Biol Chem 2017; 292:14401-14412. [PMID: 28705932 DOI: 10.1074/jbc.m117.781112] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 07/05/2017] [Indexed: 12/17/2022] Open
Abstract
Clostridium difficile is a clinically significant pathogen that causes mild-to-severe (and often recurrent) colon infections. Disease symptoms stem from the activities of two large, multidomain toxins known as TcdA and TcdB. The toxins can bind, enter, and perturb host cell function through a multistep mechanism of receptor binding, endocytosis, pore formation, autoproteolysis, and glucosyltransferase-mediated modification of host substrates. Monoclonal antibodies that neutralize toxin activity provide a survival benefit in preclinical animal models and prevent recurrent infections in human clinical trials. However, the molecular mechanisms involved in these neutralizing activities are unclear. To this end, we performed structural studies on a neutralizing monoclonal antibody, PA50, a humanized mAb with both potent and broad-spectrum neutralizing activity, in complex with TcdA. Electron microscopy imaging and multiangle light-scattering analysis revealed that PA50 binds multiple sites on the TcdA C-terminal combined repetitive oligopeptides (CROPs) domain. A crystal structure of two PA50 Fabs bound to a segment of the TcdA CROPs helped define a conserved epitope that is distinct from previously identified carbohydrate-binding sites. Binding of TcdA to the host cell surface was directly blocked by either PA50 mAb or Fab and suggested that receptor blockade is the mechanism by which PA50 neutralizes TcdA. These findings highlight the importance of the CROPs C terminus in cell-surface binding and a role for neutralizing antibodies in defining structural features critical to a pathogen's mechanism of action. We conclude that PA50 protects host cells by blocking the binding of TcdA to cell surfaces.
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Affiliation(s)
- Heather K Kroh
- From the Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2363
| | - Ramyavardhanee Chandrasekaran
- From the Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2363
| | | | - Rob Woods
- MedImmune LLC, Gaithersburg, Maryland 20878-2204
| | - Xiaofang Jin
- MedImmune LLC, Gaithersburg, Maryland 20878-2204
| | - Melanie D Ohi
- the Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee 37232-8240
| | | | | | | | - Benjamin W Spiller
- From the Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2363, .,the Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232-6600, and
| | - D Borden Lacy
- From the Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2363, .,the Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee 37212-2637
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15
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Hollevoet K, Declerck PJ. State of play and clinical prospects of antibody gene transfer. J Transl Med 2017; 15:131. [PMID: 28592330 PMCID: PMC5463339 DOI: 10.1186/s12967-017-1234-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 05/31/2017] [Indexed: 12/31/2022] Open
Abstract
Recombinant monoclonal antibodies (mAbs) are one of today's most successful therapeutic classes in inflammatory diseases and oncology. A wider accessibility and implementation, however, is hampered by the high product cost and prolonged need for frequent administration. The surge in more effective mAb combination therapies further adds to the costs and risk of toxicity. To address these issues, antibody gene transfer seeks to administer to patients the mAb-encoding nucleotide sequence, rather than the mAb protein. This allows the body to produce its own medicine in a cost- and labor-effective manner, for a prolonged period of time. Expressed mAbs can be secreted systemically or locally, depending on the production site. The current review outlines the state of play and clinical prospects of antibody gene transfer, thereby highlighting recent innovations, opportunities and remaining hurdles. Different expression platforms and a multitude of administration sites have been pursued. Viral vector-mediated mAb expression thereby made the most significant strides. Therapeutic proof of concept has been demonstrated in mice and non-human primates, and intramuscular vectored mAb therapy is under clinical evaluation. However, viral vectors face limitations, particularly in terms of immunogenicity. In recent years, naked DNA has gained ground as an alternative. Attained serum mAb titers in mice, however, remain far below those obtained with viral vectors, and robust pharmacokinetic data in larger animals is limited. The broad translatability of DNA-based antibody therapy remains uncertain, despite ongoing evaluation in patients. RNA presents another emerging platform for antibody gene transfer. Early reports in mice show that mRNA may be able to rival with viral vectors in terms of generated serum mAb titers, although expression appears more short-lived. Overall, substantial progress has been made in the clinical translation of antibody gene transfer. While challenges persist, clinical prospects are amplified by ongoing innovations and the versatility of antibody gene transfer. Clinical introduction can be expedited by selecting the platform approach currently best suited for the mAb or disease of interest. Innovations in expression platform, administration and antibody technology are expected to further improve overall safety and efficacy, and unlock the vast clinical potential of antibody gene transfer.
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Affiliation(s)
- Kevin Hollevoet
- Laboratory for Therapeutic and Diagnostic Antibodies, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven - University of Leuven, Campus Gasthuisberg O&N 2, P.B. 820, Herestraat 49, 3000 Leuven, Belgium
| | - Paul J. Declerck
- Laboratory for Therapeutic and Diagnostic Antibodies, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven - University of Leuven, Campus Gasthuisberg O&N 2, P.B. 820, Herestraat 49, 3000 Leuven, Belgium
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16
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Péchiné S, Janoir C, Collignon A. Emerging monoclonal antibodies against Clostridium difficile infection. Expert Opin Biol Ther 2017; 17:415-427. [PMID: 28274145 DOI: 10.1080/14712598.2017.1300655] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
INTRODUCTION Clostridium difficile infections are characterized by a high recurrence rate despite antibiotic treatments and there is an urgent need to develop new treatments such as fecal transplantation and immonotherapy. Besides active immunotherapy with vaccines, passive immunotherapy has shown promise, especially with monoclonal antibodies. Areas covered: Herein, the authors review the different assays performed with monoclonal antibodies against C. difficile toxins and surface proteins to treat or prevent primary or recurrent episodes of C. difficile infection in animal models and in clinical trials as well. Notably, the authors lay emphasis on the phase III clinical trial (MODIFY II), which allowed bezlotoxumab to be approved by the Food and Drug Administration and the European Medicines Agency. They also review new strategies for producing single domain antibodies and nanobodies against C. difficile and new approaches to deliver them in the digestive tract. Expert opinion: Only two human Mabs against TcdA and TcdB have been tested alone or in combination in clinical trials. However, many animal model studies have provided rationale for the use of Mabs and nanobodies in C. difficile infection and pave the way for further clinical investigation.
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Affiliation(s)
- Séverine Péchiné
- a EA4043 Faculté de Pharmacie , Univ Paris-Sud, Université Paris-Saclay , Chatenay-Malabry , France
| | - Claire Janoir
- a EA4043 Faculté de Pharmacie , Univ Paris-Sud, Université Paris-Saclay , Chatenay-Malabry , France
| | - Anne Collignon
- a EA4043 Faculté de Pharmacie , Univ Paris-Sud, Université Paris-Saclay , Chatenay-Malabry , France
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17
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Kaper JB, Flajnik MF, Mobley HLT. Editorial: Infection and immunity research at the University of Maryland, Baltimore. Pathog Dis 2016; 74:ftw100. [PMID: 27702794 DOI: 10.1093/femspd/ftw100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- James B Kaper
- Department of Microbiology and Immunology, University of Maryland School of Medicine, 685 W. Baltimore St. HSF I-Rm 380, Baltimore, MD 21201, USA
| | - Martin F Flajnik
- Department of Microbiology and Immunology, University of Maryland School of Medicine, 685 W. Baltimore St. HSF I-Rm 380, Baltimore, MD 21201, USA
| | - Harry L T Mobley
- University of Michigan, Microbiology and Immunology, 5641 Medical Science II 1150 W. Medical Center Drive, Ann Arbor, MI 48109, USA
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18
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Choe JE, Welch MD. Actin-based motility of bacterial pathogens: mechanistic diversity and its impact on virulence. Pathog Dis 2016; 74:ftw099. [PMID: 27655913 DOI: 10.1093/femspd/ftw099] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
A diverse spectrum of intracellular bacterial pathogens that inhabit the cytosol have evolved the ability to polymerize actin on their surface to power intracellular actin-based motility (ABM). These include species of Listeria, Burkholderia and Rickettsia, as well as Shigella and Mycobacteria Here, we provide an overview of the roles of bacterial ABM in survival and virulence. Moreover, we survey the molecular mechanisms of actin polymerization in host cells and describe how bacterial pathogens mimic or harness the full diversity of these mechanisms for ABM. Finally, we present ABM through a new lens by comparing motility mechanisms between related species of Listeria, Burkholderia, and Rickettsia Through these comparisons, we hope to illuminate how exploitation of different actin polymerization mechanisms influences ABM as well as pathogenicity and virulence in humans and other animals.
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Affiliation(s)
- Julie E Choe
- Department of Molecular & Cell Biology, University of California, Berkeley CA 94720 USA
| | - Matthew D Welch
- Department of Molecular & Cell Biology, University of California, Berkeley CA 94720 USA
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