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Ponzilacqua-Silva B, Dadelahi AS, Abushahba MFN, Moley CR, Skyberg JA. Vaccine Elicited Antibodies Restrict Glucose Availability to Control Brucella Infection. J Infect Dis 2024:jiae172. [PMID: 38586904 DOI: 10.1093/infdis/jiae172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 03/25/2024] [Accepted: 03/29/2024] [Indexed: 04/09/2024] Open
Abstract
The impact of vaccine-induced immune responses on host metabolite availability has not been well studied. Here we show prior vaccination alters the metabolic profile of mice challenged with Brucella melitensis. In particular, glucose levels were reduced in vaccinated mice in an antibody-dependent manner. We also found the glucose transporter gene, gluP, plays a lesser role in B. melitensis virulence in vaccinated wild-type mice relative to vaccinated mice unable to secrete antibodies. These data indicate vaccine-elicited antibodies protect the host in part by restricting glucose availability. Moreover, Brucella and other pathogens may need to employ different metabolic strategies in vaccinated hosts.
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Affiliation(s)
- Bárbara Ponzilacqua-Silva
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
| | - Alexis S Dadelahi
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
| | - Mostafa F N Abushahba
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
- Department of Zoonoses, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt
| | - Charles R Moley
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
| | - Jerod A Skyberg
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
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Abushahba MFN, Dadelahi AS, Ponzilacqua-Silva B, Moley CR, Skyberg JA. Contrasting roles for IgM and B-cell MHCII expression in Brucella abortus S19 vaccine-mediated efficacy against B. melitensis infection. mSphere 2024; 9:e0075023. [PMID: 38349167 PMCID: PMC10964430 DOI: 10.1128/msphere.00750-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 01/16/2024] [Indexed: 02/15/2024] Open
Abstract
Brucellosis, caused by the bacterium Brucella, poses a significant global threat to both animal and human health. Although commercial live Brucella vaccines including S19, RB51, and Rev1 are available for animals, their unsuitability for human use and incomplete efficacy in animals necessitate the further study of vaccine-mediated immunity to Brucella. In this study, we employed in vivo B-cell depletion, as well as immunodeficient and transgenic mouse models, to comprehensively investigate the roles of B cells, antigen uptake and presentation, antibody production, and class switching in the context of S19-mediated immunity against brucellosis. We found that antibody production, and in particular secretory IgM plays a protective role in S19-mediated immunity against virulent Brucella melitensis early after the challenge in a manner associated with complement activation. While T follicular helper cell deficiency dampened IgG production and vaccine efficacy at later stages of the challenge, this effect appeared to be independent of antibody production and rather was associated with altered T-cell function. By contrast, B-cell MHCII expression negatively impacted vaccine efficacy at later timepoints after the challenge. In addition, B-cell depletion after vaccination, but before the challenge, enhanced S19-mediated protection against brucellosis, suggesting a deleterious role of B cells during the challenge phase. Collectively, our findings indicate antibody production is protective, while B-cell MHCII expression is deleterious, to live vaccine-mediated immunity against brucellosis. IMPORTANCE Brucella is a neglected zoonotic pathogen with a worldwide distribution. Our study delves into B-cell effector functions in live vaccine-mediated immunity against brucellosis. Notably, we found antibody production, particularly secretory IgM, confers protection against virulent Brucella melitensis in vaccinated mice, which was associated with complement activation. By contrast, B-cell MHCII expression negatively impacted vaccine efficacy. In addition, B-cell depletion after vaccination, but before the B. melitensis challenge, enhanced protection against infection, suggesting a detrimental B-cell role during the challenge phase. Interestingly, deficiency of T follicular helper cells, which are crucial for aiding germinal center B cells, dampened vaccine efficacy at later stages of challenge independent of antibody production. This study underscores contrasting and phase-dependent roles of B-cell effector functions in vaccine-mediated immunity against Brucella.
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Affiliation(s)
- Mostafa F. N. Abushahba
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
- Department of Zoonoses, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt
| | - Alexis S. Dadelahi
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
| | - Bárbara Ponzilacqua-Silva
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
| | - Charles R. Moley
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
| | - Jerod A. Skyberg
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
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Moley CR, Chambers CA, Dadelahi AS, Ponzilacqua-Silva B, Abushahba MFN, Lacey CA, Franklin CL, Skyberg JA. Innate Lymphoid Cells and Interferons Limit Neurologic and Articular Complications of Brucellosis. Am J Pathol 2023; 193:1170-1184. [PMID: 37263343 PMCID: PMC10477959 DOI: 10.1016/j.ajpath.2023.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 05/10/2023] [Accepted: 05/18/2023] [Indexed: 06/03/2023]
Abstract
Brucellosis is a globally significant zoonotic disease. Human patients with brucellosis develop recurrent fever and focal complications, including arthritis and neurobrucellosis. The current study investigated the role of innate lymphoid cells (ILCs) in the pathogenesis of focal brucellosis caused by Brucella melitensis. After footpad infection, natural killer cells and ILC1 cells both limited joint colonization by Brucella. Mice lacking natural killer cells, and in particular mice lacking all ILCs, also developed marked arthritis after footpad infection. Following pulmonary infection, mice lacking adaptive immune cells and ILCs developed arthritis, neurologic complications, and meningitis. Adaptive immune cells and ILCs both limited colonization of the brain by Brucella following pulmonary infection. Transcriptional analysis of Brucella-infected brains revealed marked up-regulation of genes associated with inflammation and interferon responses, as well as down-regulation of genes associated with neurologic function. Type II interferon deficiency resulted in colonization of the brain by Brucella, but mice lacking both type I and type II interferon signaling more rapidly developed clinical signs of neurobrucellosis, exhibited hippocampal neuronal loss, and had higher levels of Brucella in their brains than mice lacking type II interferon signaling alone. Collectively, these findings indicate ILCs and interferons play an important role in prevention of focal complications during Brucella infection, and that mice with deficiencies in ILCs or interferons can be used to study pathogenesis of neurobrucellosis.
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Affiliation(s)
- Charles R Moley
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri; Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri
| | - Catherine A Chambers
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri; Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri
| | - Alexis S Dadelahi
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri; Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri
| | - Bárbara Ponzilacqua-Silva
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri; Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri
| | - Mostafa F N Abushahba
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri; Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri; Department of Zoonoses, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt
| | - Carolyn A Lacey
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri; Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri
| | - Craig L Franklin
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri; Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri
| | - Jerod A Skyberg
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri; Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri.
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4
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Dadelahi AS, Abushahba MFN, Ponzilacqua-Silva B, Chambers CA, Moley CR, Lacey CA, Dent AL, Skyberg JA. Interactions between B cells and T follicular regulatory cells enhance susceptibility to Brucella infection independent of the anti-Brucella humoral response. PLoS Pathog 2023; 19:e1011672. [PMID: 37721965 PMCID: PMC10538787 DOI: 10.1371/journal.ppat.1011672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 09/28/2023] [Accepted: 09/07/2023] [Indexed: 09/20/2023] Open
Abstract
Brucellosis, caused by facultative, intracellular Brucella spp., often results in chronic and/or lifelong infection. Therefore, Brucella must employ mechanisms to subvert adaptive immunity to cause chronic infection. B lymphocytes enhance susceptibility to infection with Brucella spp. though the mechanisms remain unclear. Here we investigated the role of antibody secretion, B cell receptor (BCR) specificity, and B cell antigen presentation on susceptibility to B. melitensis. We report that mice unable to secrete antibody do not display altered resistance to Brucella. However, animals with B cells that are unable to recognize Brucella through their BCR are resistant to infection. In addition, B cell MHCII expression enhances susceptibility to infection in a CD4+ T cell-dependent manner, and we found that follicular B cells are sufficient to inhibit CD4+ T cell-mediated immunity against Brucella. B cells promote development of T follicular helper (TFH) and T follicular regulatory (TFR) cells during Brucella infection. Inhibition of B cell and CD4+ T cell interaction via CD40L blockade enhances resistance to Brucella in a B cell dependent manner concomitant with suppression of TFH and TFR differentiation. Conversely, PD-1 blockade increases Brucella burdens in a B and CD4+ T cell dependent manner while augmenting T regulatory (TReg) and TFR responses. Intriguingly, TFR deficiency enhances resistance to Brucella via a B cell dependent, but antibody independent mechanism. Collectively, these results demonstrate B cells support TFR responses that promote susceptibility to Brucella infection independent of the antibody response.
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Affiliation(s)
- Alexis S. Dadelahi
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States of America
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, United States of America
| | - Mostafa F. N. Abushahba
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States of America
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, United States of America
- Department of Zoonoses, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt
| | - Bárbara Ponzilacqua-Silva
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States of America
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, United States of America
| | - Catherine A. Chambers
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States of America
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, United States of America
| | - Charles R. Moley
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States of America
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, United States of America
| | - Carolyn A. Lacey
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States of America
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, United States of America
| | - Alexander L. Dent
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana
| | - Jerod A. Skyberg
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States of America
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, United States of America
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5
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Abushahba MF, Dadelahi AS, Lemoine EL, Skyberg JA, Vyas S, Dhoble S, Ghodake V, Patravale VB, Adamovicz JJ. Safe Subunit Green Vaccines Confer Robust Immunity and Protection against Mucosal Brucella Infection in Mice. Vaccines (Basel) 2023; 11:vaccines11030546. [PMID: 36992130 DOI: 10.3390/vaccines11030546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 02/20/2023] [Accepted: 02/23/2023] [Indexed: 03/03/2023] Open
Abstract
Brucellosis is a zoonotic disease that causes significant negative impacts on the animal industry and affects over half a million people worldwide every year. The limited safety and efficacy of current animal brucellosis vaccines, combined with the lack of a licensed human brucellosis vaccine, have led researchers to search for new vaccine strategies to combat the disease. To this end, the present research aimed to evaluate the safety and efficacy of a green vaccine candidate that combines Brucella abortus S19 smooth lipopolysaccharide (sLPS) with Quillaja saponin (QS) or QS-Xyloglucan mix (QS-X) against mucosal brucellosis in BALB/C mice. The results of the study indicate that administering two doses of either sLPS-QS or sLPS-QS-X was safe for the animals, triggered a robust immune response, and enhanced protection following intranasal challenge with S19. Specifically, the vaccine combinations led to the secretion of IgA and IgG1 in the BALF of the immunized mice. We also found a mixed IgG1/IgG2a systemic response indicating evidence of both Th1 and Th2 activation, with a predominance of the IgG1 over the IgG2a. These candidates resulted in significant reductions in the bioburden of lung, liver, and spleen tissue compared to the PBS control group. The sLPS-QS vaccination had conferred the greatest protection, with a 130-fold reduction in Brucella burdens in lung and a 55.74-fold reduction in the spleen compared to PBS controls. Vaccination with sLPS-QS-X resulted in the highest reduction in splenic Brucella loads, with a 364.6-fold decrease in bacterial titer compared to non-vaccinated animals. The study suggests that the tested vaccine candidates are safe and effective in increasing the animals’ ability to respond to brucellosis via mucosal challenge. It also supports the use of the S19 challenge strain as a safe and cost-effective method for testing Brucella vaccine candidates under BSL-2 containment conditions.
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Affiliation(s)
- Mostafa F Abushahba
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
- Department of Zoonotic Diseases, Faculty of Veterinary Medicine, Assiut University, Assiut 71515, Egypt
| | - Alexis S Dadelahi
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
| | - Emily L Lemoine
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
| | - Jerod A Skyberg
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
| | - Swati Vyas
- Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology, N.P. Marg, Matunga (E), Mumbai 400019, Maharashtra, India
| | - Sagar Dhoble
- Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology, N.P. Marg, Matunga (E), Mumbai 400019, Maharashtra, India
| | - Vinod Ghodake
- Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology, N.P. Marg, Matunga (E), Mumbai 400019, Maharashtra, India
| | - Vandana B Patravale
- Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology, N.P. Marg, Matunga (E), Mumbai 400019, Maharashtra, India
| | - Jeffrey J Adamovicz
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
- Laboratory for Infectious Disease Research, University of Missouri, Columbia, MO 65211, USA
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6
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Skyberg JA, Chambers CA, Dadelahi AS, Moley CR, Olson RM, Logue CM. Nucleotide Receptors Mediate Protection Against Neonatal Sepsis and Meningitis Caused by Alpha-Hemolysin Expressing Escherichia coli K1. The Journal of Immunology 2022. [DOI: 10.4049/jimmunol.208.supp.51.02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Abstract
Neonatal meningitis-associated Escherichia coli (NMEC) are among the leading causes of bacterial meningitis and sepsis in newborn infants. Several virulence factors have been identified as common among NMEC, and have been shown to play an important role in the development of bacteremia and/or meningitis. However, there is significant variability in virulence factor expression between NMEC isolates, and relatively little research has been done to assess the impact of variable virulence factor expression on immune cell activation and the outcome of infection. Here we investigated the role of NMEC strain-dependent P2X receptor (P2XR) signaling on the outcome of infection in neonatal mice. We found that alpha hemolysin (HlyA)-expressing NMEC (HlyA+) induced robust P2XR-dependent macrophage cell death in vitro, while HlyA− NMEC did not. P2XR-dependent cell death was inflammasome independent, suggesting an uncoupling of P2XR and inflammasome activation in the context of NMEC infection. In vivo inhibition of P2XRs was associated with increased mortality in neonatal mice infected with HlyA+ NMEC, but had no effect on the survival of neonatal mice infected with HlyA− NMEC. Furthermore, we found that P2XR-dependent protection against HlyA+ NMEC in vivo required macrophages, but not neutrophils or NLRP3. Taken together, these data suggest that HlyA+ NMEC activate P2XRs which in turn confers macrophage dependent protection against infection in neonates. In addition, our findings indicate that strain-dependent virulence factor expression should be taken into account when studying the immune response to NMEC.
Supported by University of Missouri College of Veterinary Medicine Committee on Research.
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Chambers CA, Dadelahi AS, Moley CR, Olson RM, Logue CM, Skyberg JA. Nucleotide receptors mediate protection against neonatal sepsis and meningitis caused by alpha-hemolysin expressing Escherichia coli K1. FASEB J 2022; 36:e22197. [PMID: 35147989 DOI: 10.1096/fj.202101485r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 12/30/2021] [Accepted: 01/20/2022] [Indexed: 01/15/2023]
Abstract
Neonatal meningitis-associated Escherichia coli (NMEC) is among the leading causes of bacterial meningitis and sepsis in newborn infants. Several virulence factors have been identified as common among NMEC, and have been shown to play an important role in the development of bacteremia and/or meningitis. However, there is significant variability in virulence factor expression between NMEC isolates, and relatively little research has been done to assess the impact of variable virulence factor expression on immune cell activation and the outcome of infection. Here, we investigated the role of NMEC strain-dependent P2X receptor (P2XR) signaling on the outcome of infection in neonatal mice. We found that alpha-hemolysin (HlyA)-expressing NMEC (HlyA+ ) induced robust P2XR-dependent macrophage cell death in vitro, while HlyA- NMEC did not. P2XR-dependent cell death was inflammasome independent, suggesting an uncoupling of P2XR and inflammasome activation in the context of NMEC infection. In vivo inhibition of P2XRs was associated with increased mortality in neonatal mice infected with HlyA+ NMEC, but had no effect on the survival of neonatal mice infected with HlyA- NMEC. Furthermore, we found that P2XR-dependent protection against HlyA+ NMEC in vivo required macrophages, but not neutrophils or NLRP3. Taken together, these data suggest that HlyA+ NMEC activates P2XRs which in turn confers macrophage-dependent protection against infection in neonates. In addition, our findings indicate that strain-dependent virulence factor expression should be taken into account when studying the immune response to NMEC.
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Affiliation(s)
- Catherine A Chambers
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, USA
| | - Alexis S Dadelahi
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, USA
| | - Charles R Moley
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, USA
| | - Rachel M Olson
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, USA
| | - Catherine M Logue
- Department of Population Heath, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Jerod A Skyberg
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, USA
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Chambers CA, Lacey CA, Brown DC, Skyberg JA. Nitric oxide inhibits interleukin-1-mediated protection against Escherichia coli K1-induced sepsis and meningitis in a neonatal murine model. Immunol Cell Biol 2021; 99:596-610. [PMID: 33550610 DOI: 10.1111/imcb.12445] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 01/14/2021] [Accepted: 02/05/2021] [Indexed: 01/03/2023]
Abstract
Neonatal meningitis-associated Escherichia coli (NMEC) is a leading cause of sepsis and meningitis in newborn infants. Neonates are known to have impaired inflammasome activation and interleukin (IL)-1 production. However, it is unknown what role this plays in the context of NMEC infection. Here we investigated the role of IL-1 signaling in the pathogenesis of NMEC infection. We found both IL-1β and IL-1α were secreted from macrophages and microglial cells in response to NMEC in a Toll-like receptor 4- and NLR family pyrin domain containing 3 (NPLR3)-dependent manner. Intracerebral infection of adult mice indicated a protective role of IL-1 signaling during NMEC infection. However, IL-1 receptor blockade in wild-type neonatal mice did not significantly alter bacterial loads in the blood or brain, and we, therefore, investigated whether protection conferred by IL-1 was age dependent. Neonates are known to have increased nitric oxide (NO) levels compared with adults, and we found NO inhibited the secretion of IL-1 by macrophages in response to NMEC. In contrast to our results in wild-type neonates, blockade of IL-1 receptor in neonates lacking inducible nitric oxide synthase (iNOS) led to significantly increased bacterial loads in the blood and brain. These data indicate IL-1 signaling is protective during NMEC infection in neonates only when iNOS is absent. Collectively, our findings suggest that increased NO production by neonates inhibits IL-1 production, and that this suppresses the protective role of IL-1 signaling in response to NMEC infection. This may indicate a general mechanism for increased susceptibility of neonates to infection and could lead to new therapeutic strategies in the future.
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Affiliation(s)
- Catherine A Chambers
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO, USA
| | - Carolyn A Lacey
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO, USA.,Department of Immunology, Duke University Medical Center, Durham, NC, USA
| | - Dana C Brown
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO, USA
| | - Jerod A Skyberg
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO, USA
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9
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Lacey CA, Chambers CA, Mitchell WJ, Skyberg JA. IFN-γ-dependent nitric oxide suppresses Brucella-induced arthritis by inhibition of inflammasome activation. J Leukoc Biol 2019; 106:27-34. [PMID: 30748031 DOI: 10.1002/jlb.4mia1018-409r] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 01/14/2019] [Accepted: 01/31/2019] [Indexed: 12/28/2022] Open
Abstract
Brucellosis, caused by the intracellular bacterial pathogen Brucella, is a globally important zoonotic disease for which arthritis is the most common focal complication in humans. Wild-type mice infected systemically with Brucella typically do not exhibit arthritis, but mice lacking IFN-γ develop arthritis regardless of the route of Brucella infection. Here, we investigated mechanisms by which IFN-γ suppresses Brucella-induced arthritis. Several cell types, including innate lymphoid cells, contributed to IFN-γ production and suppression of joint swelling. IFN-γ deficiency resulted in elevated joint IL-1β levels, and severe joint inflammation that was entirely inflammasome dependent, and in particular, reliant on the NLRP3 inflammasome. IFN-γ was vital for induction of the nitric oxide producing enzyme, iNOS, in infected joints, and nitric oxide directly inhibited IL-1β production and inflammasome activation in Brucella-infected macrophages in vitro. During in vivo infection, iNOS deficiency resulted in an increase in IL-1β and inflammation in Brucella-infected joints. Collectively, this data indicate that IFN-γ prevents arthritis both by limiting Brucella infection, and by inhibiting excessive inflammasome activation through the induction of nitric oxide.
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Affiliation(s)
- Carolyn A Lacey
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA.,Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
| | - Catherine A Chambers
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA.,Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
| | - William J Mitchell
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA
| | - Jerod A Skyberg
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA.,Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
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10
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Dadelahi AS, Lacey CA, Skyberg JA. IFN-γ deficiency alters splenic compartment cellular composition and Brucella distribution in a murine model of brucellosis. The Journal of Immunology 2018. [DOI: 10.4049/jimmunol.200.supp.117.40] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Despite more than a century of research, brucellosis remains a major zoonotic threat with an estimated 500,000 human cases annually. No licensed vaccine exists to counter Brucella infection, leaving many who contract brucellosis with a chronic and debilitating disease. Immunohistochemistry studies have identified targets of Brucella infection in vivo. However, due to the low detection limit of this technique, high infectious doses of Brucella or immunodeficient mice are employed which likely changes the composition of the infected tissue. We and others observed increased splenic bacterial burden and susceptibility to Brucella infection in mice deficient in IFN-γ. Therefore, to determine if IFN-γ changes splenic composition and cellular distribution of Brucella, we performed live cell sorting on spleens from Brucella- infected wild-type (WT) and IFN-γ−/− mice. Spleens from Brucella-infected IFN-γ−/− mice exhibited a lower proportion of B cells and an increased proportion of neutrophils and macrophages compared to WT mice. Interestingly, 90% of intracellular, viable Brucella from WT spleens during chronic infection was in B cells while the proportion of bacterial burden was similar amongst B cells, macrophages, and neutrophils within IFN-γ−/− spleens. In studies using B-cell deficient (μMT−/−) mice challenged with Brucella, we found significantly decreased bacterial burden in μMT−/− spleens compared to WT mice despite similar levels recovered from the joint between both groups. Collectively, these findings indicate that IFN-γ deficiency alters the distribution of cells within the splenic compartment and that B cells enhance Brucella burden in the spleen.
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Lacey C, Mitchell WJ, Skyberg JA. Inflammasomes confer protection via IL-18 and pyroptosis, and are negatively regulated by IFN-γ-dependent nitric oxide during Brucella infection. The Journal of Immunology 2018. [DOI: 10.4049/jimmunol.200.supp.115.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Brucellosis, caused by the intracellular bacterial pathogen Brucella, is a zoonotic disease for which arthritis is the most common focal complication in humans. Here we show caspase-1 (casp1) and caspase-11 (casp11) initiate Brucella-induced joint inflammation, but later in infection also restrict Brucella replication. In contrast, AIM2 and NLRP3 were dispensable for control of joint infection by Brucella. Both IL-1 and IL-18 promoted joint inflammation, however only IL-18 contributed to protection against Brucella infection of the joint. In vitro studies demonstrated that casp1 and casp11 both induce pyroptosis which limited Brucella infection in macrophages. While IFN-γ production in part required casp1/11 and IL-18, casp1/11-dependent clearance of Brucella was only partially IFN-γ dependent. However, IFN-γ deficiency resulted in severe inflammation that was entirely inflammasome dependent, and in particular reliant on NLRP3. IFN-γ was vital for induction of the nitric oxide (NO) producing enzyme, iNOS, in infected joints, and NO inhibited casp1 activation in Brucella-infected macrophages in vitro. During Brucella infection in vivo, iNOS inhibition exacerbated arthritis, and administration of a NO donor reduced joint inflammation in IFN-γ-deficient mice. Collectively these data demonstrate inflammasomes induce early inflammation in an IL-18 and IL-1 dependent manner, and inflammasome-dependent IL-18 and pyroptosis restrict Brucella burdens in the joint. Moreover, IFN-γ reduces inflammation by inhibiting excessive casp1 activation through production of NO. Thus NO donors, in combination with antibiotics, may be an effective therapy for treating Brucella-induced inflammation.
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Skyberg JA, Lacey CA. Hematopoietic MyD88 and IL-18 are essential for IFN-γ-dependent restriction of type A Francisella tularensis infection. J Leukoc Biol 2017; 102:1441-1450. [PMID: 28951422 DOI: 10.1189/jlb.4a0517-179r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 08/03/2017] [Accepted: 08/29/2017] [Indexed: 12/11/2022] Open
Abstract
Francisella tularensis is a highly infectious intracellular bacterium that causes the potentially fatal disease tularemia. We used mice with conditional MyD88 deficiencies to investigate cellular and molecular mechanisms by which MyD88 restricts type A F. tularensis infection. F. tularensis-induced weight loss was predominately dependent on MyD88 signaling in nonhematopoietic cells. In contrast, MyD88 signaling in hematopoietic cells, but not in myeloid and dendritic cells, was essential for control of F. tularensis infection in tissue. Myeloid and dendritic cell MyD88 deficiency also did not markedly impair cytokine production during infection. Although the production of IL-12 or -18 was not significantly reduced in hematopoietic MyD88-deficient mice, IFN-γ production was abolished in these animals. In addition, neutralization studies revealed that control of F. tularensis infection mediated by hematopoietic MyD88 was entirely dependent on IFN-γ. Although IL-18 production was not significantly affected by MyD88 deficiency, IL-18 was essential for IFN-γ production and restricted bacterial replication in an IFN-γ-dependent manner. Caspase-1 was also found to be partially necessary for the production of IL-18 and IFN-γ and for control of F. tularensis replication. Our collective data show that the response of leukocytes to caspase-1-dependent IL-18 via MyD88 is critical, whereas MyD88 signaling in myeloid and dendritic cells is dispensable for IFN-γ-dependent control of type A F. tularensis infection.
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Affiliation(s)
- Jerod A Skyberg
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA; and .,Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
| | - Carolyn A Lacey
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA; and.,Laboratory for Infectious Disease Research, University of Missouri, Columbia, Missouri, USA
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Lacey C, Skyberg JA. Inflammasomes promote the initiation of Brucella induced arthritis in an IL-18 dependent manner and mediate Brucella clearance independently of IFN-γ. The Journal of Immunology 2017. [DOI: 10.4049/jimmunol.198.supp.64.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
Brucellosis, caused by the intracellular bacterial pathogen Brucella, is a zoonotic disease for which infection of the joints is the most common focal complication in humans. The purpose of this study was to identify if Brucella activation of inflammasomes and in turn caspase1/11 activation is responsible for inducing arthritis. Here we report caspase-1/11−/− (casp1/11−/−) mice had reduced swelling, inflammation and inflammatory cytokine levels early in infection relative to wild-type “WT” mice. Later in infection, joint inflammation was similar between WT and casp1/11−/− mice, but bacterial loads and swelling were greater in casp1/11−/− joints. While IL-1Rdeficiency reduced joint swelling, this effect occurred later and was not of the same magnitude as casp1/11 deficiency, indicating an IL-1 independent role of casp1/11. Casp1/11 induced inflammation was partially dependent on IL-18, and IFN-γ levels were reduced in both casp1/11−/− and IL-18-deficient mice relative to WT mice early in infection. However, while IFN-γ and casp1/11 both played a role in controlling joint Brucella burdens, an additive effect of these deficiencies was observed indicating that the protective effects of IFN-γ and casp1/11 on bacterial clearance are not interdependent. Enhanced arthritis and musculoskeletal inflammation was observed in IFN-γ-deficient, relative to WT mice. However, neutralization of IFN-γ in casp1/11−/− mice did not result in enhanced inflammation. Collectively these data demonstrate casp1/11 induces early inflammation in an IL-18 dependent manner. Moreover, there is an IFN-γ independent role of casp1/11 in joint Brucella clearance, and casp1/11 is responsible for enhanced inflammation observed in IFN-γ-deficient mice.
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Skyberg JA, Lacey CA. Hematopoietic MyD88 mediates protection against virulent Francisella tularensis infection via IFN-γ, but does not require myeloid or dendritic cell MyD88 signaling. The Journal of Immunology 2017. [DOI: 10.4049/jimmunol.198.supp.148.24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Francisella tularensis is a highly infectious intracellular bacterium that causes the potentially fatal disease tularemia. MyD88 has previously been shown to confer protection against both attenuated and virulent strains of F. tularensis, however the underlying mechanisms of protection are largely unexplored. Here we investigated cell-specific mechanisms of protection against virulent F. tularensis infection using mice with conditional MyD88 deficiencies. MyD88 deficiency in myeloid or dendritic cells did not enhance susceptibility to F. tularensis, regardless of the route of infection. In addition, myeloid or dendritic cell MyD88 deficiency did not markedly hinder the production of inflammatory cytokines. In contrast, MyD88−/− mice, or mice with hematopoietic MyD88 deficiency display elevated bacterial burdens, and markedly reduced cytokine levels. While IL-12 levels were not diminished in MyD88−/− or hematopoietic MyD88-deficient mice infected with F. tularensis, IFN-γ production was abolished in these animals. In particular, IFN-γ production by splenic NK cells was abated in mice lacking hematopoietic MyD88. Neutralization of IFN-γ from wild-type, but not hematopoietic MyD88-deficient mice, resulted in elevated tissue F. tularensis burdens. Caspase-1/11−/− mice also displayed enhanced bacterial burdens, diminished serum IL-18 levels, and reduced IFN-γ production. Collectively, our data shows that hematopoietic MyD88 is required for IFN-γ production that is protective against F. tularensis infection. As IL-18 requires MyD88 for signaling to induce IFN-γ production, MyD88 signaling in hematopoietic cells, such as NK cells, may result in the production of protective IFN-γ via caspase1/11 dependent IL-18.
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Keleher LL, Skyberg JA. Activation of bovine neutrophils by Brucella spp. Vet Immunol Immunopathol 2016; 177:1-6. [PMID: 27436438 DOI: 10.1016/j.vetimm.2016.05.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 05/03/2016] [Accepted: 05/10/2016] [Indexed: 01/18/2023]
Abstract
Brucellosis is a globally important zoonotic infectious disease caused by gram negative bacteria of the genus Brucella. While many species of Brucella exist, Brucella melitensis, Brucella abortus, and Brucella suis are the most common pathogens of humans and livestock. The virulence of Brucella is largely influenced by its ability to evade host factors, including phagocytic killing mechanisms, which are critical for the host response to infection. The aim of this study was to characterize the bovine neutrophil response to virulent Brucella spp. Here, we found that virulent strains of smooth B. abortus, B. melitensis, B. suis, and virulent, rough, strains of Brucella canis possess similar abilities to resist killing by resting, or IFN-γ-activated, bovine neutrophils. Bovine neutrophils responded to infection with a time-dependent oxidative burst that varied little between Brucella spp. Inhibition of TAK1, or SYK kinase blunted the oxidative burst of neutrophils in response to Brucella infection. Interestingly, Brucella spp. did not induce robust death of bovine neutrophils. These results indicate that bovine neutrophils respond similarly to virulent Brucella spp. In addition, virulent Brucella spp., including naturally rough strains of B. canis, have a conserved ability to resist killing by bovine neutrophils.
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Affiliation(s)
- Lauren L Keleher
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, 65211, United States; Laboratory for Infectious Disease Research, University of Missouri, Columbia, MO, 65211, United States
| | - Jerod A Skyberg
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, 65211, United States; Laboratory for Infectious Disease Research, University of Missouri, Columbia, MO, 65211, United States.
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Lacey CA, Keleher LL, Mitchell WJ, Brown CR, Skyberg JA. CXCR2 Mediates Brucella-Induced Arthritis in Interferon γ-Deficient Mice. J Infect Dis 2016; 214:151-60. [PMID: 26951819 DOI: 10.1093/infdis/jiw087] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 02/29/2016] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Brucella species are facultative intracellular gram-negative bacteria that cause brucellosis, a common global zoonosis. Infection of the joints is the most common focal complication of brucellosis in humans. The purpose of this study was to identify mediators of focal inflammation during brucellosis. METHODS Wild-type (WT) mice are naturally resistant to Brucella infection; therefore, we infected anti-interferon γ (IFN-γ)-treated, or IFN-γ(-/-) mice with Brucella to induce osteoarticular and musculoskeletal inflammation, as we previously described. Mice were infected intraperitoneally with Brucella melitensis, and the clinical course of disease, histopathologic changes, and cytokine levels were compared among groups. RESULTS Rag1(-/-) mice (B- and T-cell deficient) and µMT(-/-) mice (B-cell deficient) developed paw inflammation at a similar rate and severity as WT mice following infection with B. melitensis and treatment with anti-IFN-γ. Joints from B. melitensis-infected IFN-γ(-/-) mice had markedly increased levels of CCR2 and CXCR2 ligands. While anti-IFN-γ-treated CCR2(-/-) and WT mice behaved similarly, anti-IFN-γ-treated CXCR2(-/-) or IFN-γ(-/-)/CXCR2(-/-) mice had strikingly reduced focal swelling relative to anti-IFN-γ-treated WT or IFN-γ(-/-) mice, respectively. Additionally, neutrophil recruitment was dependent on CXCR2. CONCLUSIONS Adaptive immune cells and CCR2 are dispensable, while CXCR2 is necessary for Brucella-induced focal neutrophil recruitment and inflammation.
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Affiliation(s)
- Carolyn A Lacey
- Department of Veterinary Pathobiology, College of Veterinary Medicine Laboratory for Infectious Disease Research, University of Missouri, Columbia
| | - Lauren L Keleher
- Department of Veterinary Pathobiology, College of Veterinary Medicine Laboratory for Infectious Disease Research, University of Missouri, Columbia
| | | | - Charles R Brown
- Department of Veterinary Pathobiology, College of Veterinary Medicine
| | - Jerod A Skyberg
- Department of Veterinary Pathobiology, College of Veterinary Medicine Laboratory for Infectious Disease Research, University of Missouri, Columbia
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Abstract
Francisella tularensis is a gram-negative bacterium that causes the zoonotic disease tularemia. Francisella is highly infectious via the respiratory route (~10 CFUs) and pulmonary infections due to type A strains of F. tularensis are highly lethal in untreated patients (>30%). In addition, no vaccines are licensed to prevent tularemia in humans. Due to the high infectivity and mortality of pulmonary tularemia, F. tularensis has been weaponized, including via the introduction of antibiotic resistance, by several countries. Because of the lack of efficacious vaccines, and concerns about F. tularensis acquiring resistance to antibiotics via natural or illicit means, augmentation of host immunity, and humoral immunotherapy have been investigated as countermeasures against tularemia. This manuscript will review advances made and challenges in the field of immunotherapy against tularemia.
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Affiliation(s)
- Jerod A Skyberg
- Department of Veterinary Pathobiology and Laboratory for Infectious Disease Research; University of Missouri; Columbia, MO USA
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Skyberg JA, Thornburg T, Kochetkova I, Layton W, Callis G, Rollins MF, Riccardi C, Becker T, Golden S, Pascual DW. IFN-γ-deficient mice develop IL-1-dependent cutaneous and musculoskeletal inflammation during experimental brucellosis. J Leukoc Biol 2012; 92:375-87. [PMID: 22636321 DOI: 10.1189/jlb.1211626] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Human brucellosis exhibits diverse pathological manifestations that can affect almost any organ. In particular, osteoarticular complications are the most common focal manifestation of brucellosis and occur in 40-80% of patients. In immunocompetent mice, Brucella replication is generally restricted to the spleen, liver, and to a lesser extent, LNs, thereby limiting their use for study of focal inflammation often found in brucellosis. Here, we report that nasal, oral, or peritoneal infection of IFN-γ(-/-) mice with WT Brucella melitensis or Brucella abortus results in joint and periarticular tissue inflammation. Histological analysis of the affected joints revealed inflammatory infiltrates and debris within the joint space colocalizing with Brucella antigen. Osteoarthritis, necrosis, periarticular soft tissue inflammation, and substantial brucellae burdens were observed. Oral rifampicin was effective in clearing infection and halting further progression of focal inflammation from infected IFN-γ(-/-) mice, although some symptoms and swelling remained. Elevated IL-1 β, but not TNF-α, IL-6, or IL-17, was detected in joint homogenates from infected IFN-γ(-/-) mice. Whereas more susceptible to systemic infection, IL-1R(-/-) mice depleted of IFN-γ were more resistant to focal inflammation than WT mice similarly depleted of IFN-γ. Collectively, these results show IFN-γ(-/-) mice represent a potential model for study of focal inflammation attributed to Brucella infection and will allow evaluation of intervention strategies targeting IL-1, IL-1R, or other inflammatory mediators, with the potential to complement antibiotic-based therapies.
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Affiliation(s)
- Jerod A Skyberg
- Department of Immunology and Infectious Diseases, Montana State University, Bozeman, Montana, USA
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Huarte E, Rynda-Apple A, Riccardi C, Skyberg JA, Golden S, Rollins MF, Ramstead AG, Jackiw LO, Maddaloni M, Pascual DW. Tolerogen-induced interferon-producing killer dendritic cells (IKDCs) protect against EAE. J Autoimmun 2011; 37:328-41. [PMID: 22018711 DOI: 10.1016/j.jaut.2011.09.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 09/13/2011] [Accepted: 09/17/2011] [Indexed: 11/15/2022]
Abstract
Natural killer (NK) cells and dendritic cells (DCs) have been shown to link the innate and adaptive immune systems. Likewise, a new innate cell subset, interferon-producing killer DCs (IKDCs), shares phenotypic and functional characteristics with both DCs and NK cells. Here, we show IKDCs play an essential role in the resolution of experimental autoimmune encephalomyelitis (EAE) upon treatment with the tolerizing agent, myelin oligodendrocyte glycoprotein (MOG), genetically fused to reovirus protein σ1 (termed MOG-pσ1). Activated IKDCs were recruited subsequent MOG-pσ1 treatment of EAE, and disease resolution was abated upon NK1.1 cell depletion. These IKDCs were able to kill activated CD4(+) T cells and mature dendritic DCs, thus, contributing to EAE remission. In addition, IKDCs were responsible for MOG-pσ1-mediated MOG-specific regulatory T cell recruitment to the CNS. The IKDCs induced by MOG-pσ1 expressed elevated levels of HVEM for interactions with cognate ligand-positive cells: LIGHT(+) NK and T(eff) cells and BTLA(+) B cells. Further characterization revealed these activated IKDCs being MHC class II(high), and upon their adoptive transfer (CD11c(+)NK1.1(+)MHC class II(high)), IKDCs, but not CD11c(+)NK1.1(+)MHC class II(intermediate/low) (unactivated) cells, conferred protection against EAE. These activated IKDCs showed enhanced CD107a, PD-L1, and granzyme B expression and could present OVA, unlike unactivated IKDCs. Thus, these results demonstrate the interventional potency induced HVEM(+) IKDCs to resolve autoimmune disease.
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Affiliation(s)
- Eduardo Huarte
- Department of Immunology and Infectious Diseases, Montana State University, 960 Technology Blvd., Bozeman, MT 59718, USA
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Skyberg JA, Robison A, Golden S, Rollins MF, Callis G, Huarte E, Kochetkova I, Jutila MA, Pascual DW. Apple polyphenols require T cells to ameliorate dextran sulfate sodium-induced colitis and dampen proinflammatory cytokine expression. J Leukoc Biol 2011; 90:1043-54. [PMID: 21693591 DOI: 10.1189/jlb.0311168] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Human IBD, including UC and Crohn's disease, is characterized by a chronic, relapsing, and remitting condition that exhibits various features of immunological inflammation and affects at least one/1000 people in Western countries. Polyphenol extracts from a variety of plants have been shown to have immunomodulatory and anti-inflammatory effects. In this study, treatment with APP was investigated to ameliorate chemically induced colitis. Oral but not peritoneal administration of APP during colitis induction significantly protected C57BL/6 mice against disease, as evidenced by the lack of weight loss, colonic inflammation, and shortening of the colon. APP administration dampened the mRNA expression of IL-1β, TNF-α, IL-6, IL-17, IL-22, CXCL9, CXCL10, CXCL11, and IFN-γ in the colons of mice with colitis. APP-mediated protection requires T cells, as protection was abated in Rag-1(-/-) or TCRα(-/-) mice but not in IL-10(-/-), IRF-1(-/-), μMT, or TCRδ(-/-) mice. Administration of APP during colitis to TCRα(-/-) mice actually enhanced proinflammatory cytokine expression, further demonstrating a requirement for TCRαβ cells in APP-mediated protection. APP treatment also inhibited CXCR3 expression by TCRαβ cells, but not B or NK cells, in the colons of mice with colitis; however, depletion of CD4(+) or CD8(+) T cells alone did not abolish APP-mediated protection. Collectively, these results show that oral administration of APP protects against experimental colitis and diminishes proinflammatory cytokine expression via T cells.
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Affiliation(s)
- Jerod A Skyberg
- Department of Immunology and Infectious Diseases, Montana State University, Bozeman, Montana, USA
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Rynda-Apple A, Huarte E, Maddaloni M, Callis G, Skyberg JA, Pascual DW. Active immunization using a single dose immunotherapeutic abates established EAE via IL-10 and regulatory T cells. Eur J Immunol 2010; 41:313-23. [PMID: 21268002 DOI: 10.1002/eji.201041104] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Revised: 11/04/2010] [Accepted: 11/17/2010] [Indexed: 11/11/2022]
Abstract
Stimulation of Ag-specific inducible Treg can enhance resolution of autoimmune disease. Conventional methods to induce Treg often require induction of autoimmune disease or subjection to infection. Reovirus adhesin, protein σ1 (pσ1), can successfully facilitate tolerance when fused to a tolerogen. We tested whether myelin oligodendrocyte glycoprotein (MOG) fused to pσ1 (MOG-pσ1) can stimulate Ag-specific Treg. We show that C57BL/6 mice treated nasally with MOG-pσ1 fail to induce MOG-specific Abs and delayed-type hypersensitivity (DTH) responses and resist EAE. Such resistance was attributed to stimulation of Foxp3(+) Treg, as well as Th2 cells. MOG-pσ1's protective capacity was abrogated in IL-10(-/-) mice, but restored when adoptively transferred with MOG-pσ1-induced Treg. As a therapeutic, MOG-pσ1 diminished EAE within 24 h of nasal application, unlike recombinant MOG (rMOG), pσ1, or pσ1+rMOG, implicating the importance of Ag specificity by pσ1-based therapeutics. MOG-pσ1-treated mice showed elevated IL-4, IL-10, and IL-28 production by CD4(+) T cells, unlike rMOG treated or control mice that produced elevated IFN-γ or IL-17, respectively. These data show the feasibility of using pσ1 as a tolerogen platform for Ag-specific tolerance induction and highlight its potential use as an immunotherapeutic for autoimmunity.
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Affiliation(s)
- Agnieszka Rynda-Apple
- Department of Immunology & Infectious Diseases, Montana State University, Technology Blvd., Bozeman, MT 59717-3610, USA
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Skyberg JA, Thornburg T, Pascual DW. IL-17 is required for protective immunity to nasal Brucella infections in an IFN-γ-dependent fashion (39.23). The Journal of Immunology 2009. [DOI: 10.4049/jimmunol.182.supp.39.23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Th1 and Th17 cells are the principal mediators of the inflammatory pathways. While the role of Th1 cells have been extensively studied for Brucella infections, there is little information on the function of IL-17 in response to Brucella infections. To evaluate such role, mice functionally deficient in IL-17 or IL-17 receptor (IL-17R-/-) mice were more susceptible to nasal Brucella infection than immunocompetent mice as evidenced by increased splenic weights and splenic CFUs. Interestingly, inhibition of IL-17 failed to enhance the IFN-γ response, but instead RT-PCR analysis revealed greater lung IL-13 mRNA transcripts than lungs from IL-17-sufficient mice. Splenic mononuclear cells from Brucella-infected mice depleted of IL-17 produced more IL-10, but less IFN-γ and IL-17 upon subsequent restimulation with heat-killed brucellae than the same cells from IL-17-sufficient mice. Interestingly, splenic mononuclear cells from infected IFN-γ-/- mice produced less IL-17, indicating that mice blocked in either IL-17 or IFN-γ pathways are impaired in their ability to produce either cytokine when infected with Brucella. These results implicate IL-17 is important for protection against nasal Brucella infections, and that IL-17 in combination with IFN-γ modulates the host immune responses to Brucella. This work is supported by USDA 2007-0612 and 2008-03776.
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Skyberg JA, Johnson TJ, Nolan LK. Mutational and transcriptional analyses of an avian pathogenic Escherichia coli ColV plasmid. BMC Microbiol 2008; 8:24. [PMID: 18230176 PMCID: PMC2270849 DOI: 10.1186/1471-2180-8-24] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Accepted: 01/29/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Previously we described a 184-kb ColV plasmid, pAPEC-O2-ColV, that contributed to the ability of an E. coli to kill avian embryos, grow in human urine, and colonize the murine kidney. Here, the roles of several genes encoded by this plasmid in virulence were assessed using mutational and transcriptional analyses. METHODS Genes chosen for deletion were iss, tsh, iutA, iroN, sitA, and cvaB. In addition, a 35-kb region of the plasmid, containing iss, tsh, and the ColV and iro operons, along with a 15-kb region containing both the aerobactin and sit operons, were deleted. Mutants were compared to the wild-type (APEC O2) for lethality to chick embryos and growth in human urine. Expression of the targeted genes was also assessed under these same conditions using RT-PCR RESULTS: No significant differences between the mutants and the wild-type in these phenotypic traits were detected. However, genes encoding known or predicted iron transport systems were up-regulated during growth in human urine, as compared to growth in LB broth, while iss, hlyF, and iroN were strongly up-regulated in chick embryos. CONCLUSION While no difference was observed between the mutant strains and their wild-type parent in the phenotypic traits assayed, we reasoned that some compensatory virulence mechanism, insensitivity of the virulence assays, or other factor could have obscured changes in the virulence of the mutants. Indeed we found several of these genes to be up-regulated in human urine and/or in the chick embryo, suggesting that certain genes linked to ColV plasmids are involved in the establishment of avian extraintestinal infection.
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Affiliation(s)
- Jerod A Skyberg
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA.
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Lynne AM, Skyberg JA, Logue CM, Doetkott C, Foley SL, Nolan LK. Characterization of a series of transconjugant mutants of an avian pathogenic Escherichia coli isolate for resistance to serum complement. Avian Dis 2007; 51:771-6. [PMID: 17992940 DOI: 10.1637/0005-2086(2007)51[771:coasot]2.0.co;2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Colibacillosis, caused by avian pathogenic Escherichia coli (APEC) is a major problem for the poultry industry resulting in significant losses annually. Previous work in our lab and by others has shown that the increased serum survival gene (iss) is a common trait associated with the virulence of APEC. This gene was first described for its contributions to E. coli serum resistance. However, recently published research has called the contribution of iss to this trait into question. In the present study, the level of serum resistance conferred on an E. coli isolate by iss is examined. Additionally, the contribution of lambda bor gene to E. coli serum resistance is studied, as iss is thought to be derived from bor and bor occurs commonly among E. coli. To better understand the iss and bor contributions to serum resistance, a series of iss and bor mutants was generated. An iss deletion (iss-) mutant showed a significant drop in its resistance to serum. Similarly, a bor mutant showed a drop in serum resistance but not as drastic as that observed with the iss mutant, suggesting that iss contributes more to serum resistance than bor in this E. coli strain. Also, when iss was reintroduced into the iss- mutant the wild-type level of serum resistance was restored, confirming that the deletion of iss was responsible for the change in resistance seen in the mutant.
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Affiliation(s)
- Aaron M Lynne
- National Farm Medicine Center, Marshfield Clinic Research Foundation, Marshfield, WI 54449, USA
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Abstract
AIMS To assess the abilities of 105 avian pathogenic Escherichia coli (APEC) and 103 avian faecal commensal E. coli (AFEC) to form biofilms on a plastic surface and to investigate the possible association of biofilm formation with the phylotype of these isolates. METHODS AND RESULTS Biofilm production was assessed in 96-well microtitre plates using three different media, namely, M63 minimal medium supplemented with glucose and casamino acids, brain-heart infusion broth, and diluted tryptic soy broth. Avian E. coli are highly variable in their ability to form biofilms. In fact, no strain produced a strong biofilm in all three types of media; however, most (75.7% AFEC and 55.2% APEC) were able to form a moderate or strong biofilm in at least one medium. Biofilm formation in APEC seems to be mostly limited to nutrient deplete media; whereas, AFEC are able to form biofilms in both nutrient deplete and replete media. Also, biofilm formation in E. coli from phylogenetic groups B2, D and B1 was induced by nutrient deplete conditions; whereas, biofilm formation by members of phylogenetic group A was strongest in a rich medium. CONCLUSIONS Biofilm formation by APEC and phylotypes B2, D and B1 is induced by nutrient deplete conditions, while AFEC are able to form biofilms in both nutrient rich and deplete media. SIGNIFICANCE AND IMPACT OF THE STUDY This is the first study to investigate biofilm formation by a large sample of avian E. coli isolates, and it provides insight into the conditions that induce biofilm formation in relation to the source (APEC or AFEC) and phylogenetic group (A, B1, B2 and D) of an isolate.
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Affiliation(s)
- J A Skyberg
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
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26
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Abstract
AIMS To confirm the presence of Iss and Bor on the outer membrane of Escherichia coli using Western blots of outer membrane protein (OMP) preparations and fluorescence microscopy, and explore the use of fluorescence microscopy for the detection of avian pathogenic E. coli (APEC) and diagnosis of avian colibacillosis. METHODS AND RESULTS Knockout mutants of iss and bor were created using a one-step recombination of target genes with PCR-generated antibiotic resistance cassettes. Anti-Iss monoclonal antibodies (Mabs) that cross-react with Bor protein were used to study the mutants relative to the wild-type organism. These Mabs were used as reagents to study OMP preparations of the mutants with Western blotting and intact E. coli cells with fluorescence microscopy. Iss and Bor were detected in Western blots of OMP preparations of the wild type. Also, Iss was detected on Deltabor mutants, and Bor was detected on Deltaiss mutants. Iss and Bor were also detected on the surface of the intact, wild-type cells and mutants using fluorescence microscopy. CONCLUSIONS These results demonstrate that Bor and Iss are exposed on E. coli's outer membrane where they may be recognized by the host's immune system. SIGNIFICANCE AND IMPACT OF THE STUDY To our knowledge, this is the first report confirming Iss' location in the outer membrane of an E. coli isolate. Such surface exposure has implications for the use of these Mabs for APEC detection and colibacillosis control.
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Affiliation(s)
- A M Lynne
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
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27
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Johnson TJ, Kariyawasam S, Wannemuehler Y, Mangiamele P, Johnson SJ, Doetkott C, Skyberg JA, Lynne AM, Johnson JR, Nolan LK. The genome sequence of avian pathogenic Escherichia coli strain O1:K1:H7 shares strong similarities with human extraintestinal pathogenic E. coli genomes. J Bacteriol 2007; 189:3228-36. [PMID: 17293413 PMCID: PMC1855855 DOI: 10.1128/jb.01726-06] [Citation(s) in RCA: 284] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Escherichia coli strains that cause disease outside the intestine are known as extraintestinal pathogenic E. coli (ExPEC) and include human uropathogenic E. coli (UPEC) and avian pathogenic E. coli (APEC). Regardless of host of origin, ExPEC strains share many traits. It has been suggested that these commonalities may enable APEC to cause disease in humans. Here, we begin to test the hypothesis that certain APEC strains possess potential to cause human urinary tract infection through virulence genotyping of 1,000 APEC and UPEC strains, generation of the first complete genomic sequence of an APEC (APEC O1:K1:H7) strain, and comparison of this genome to all available human ExPEC genomic sequences. The genomes of APEC O1 and three human UPEC strains were found to be remarkably similar, with only 4.5% of APEC O1's genome not found in other sequenced ExPEC genomes. Also, use of multilocus sequence typing showed that some of the sequenced human ExPEC strains were more like APEC O1 than other human ExPEC strains. This work provides evidence that at least some human and avian ExPEC strains are highly similar to one another, and it supports the possibility that a food-borne link between some APEC and UPEC strains exists. Future studies are necessary to assess the ability of APEC to overcome the hurdles necessary for such a food-borne transmission, and epidemiological studies are required to confirm that such a phenomenon actually occurs.
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Affiliation(s)
- Timothy J Johnson
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, 1802 Elwood Drive, VMRI #2, Iowa State University, Ames, IA 50011, USA
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Skyberg JA, Johnson TJ, Johnson JR, Clabots C, Logue CM, Nolan LK. Acquisition of avian pathogenic Escherichia coli plasmids by a commensal E. coli isolate enhances its abilities to kill chicken embryos, grow in human urine, and colonize the murine kidney. Infect Immun 2006; 74:6287-92. [PMID: 16954398 PMCID: PMC1695531 DOI: 10.1128/iai.00363-06] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have found an avian pathogenic Escherichia coli (APEC) plasmid, pAPEC-O2-ColV, which contains many of the genes associated with APEC virulence and also shows similarity in content to a plasmid and pathogenicity island of human uropathogenic E. coli (UPEC). To test the possible role of this plasmid in virulence, it was transferred by conjugation along with a large R plasmid, pAPEC-O2-R, into a commensal avian E. coli strain. The transconjugant was compared to recipient strain NC, UPEC strain HE300, and donor strain APEC O2 using various assays, including lethality for chicken embryos, growth in human urine, and ability to cause urinary tract infection in mice. The transconjugant killed significantly more chicken embryos than did the recipient. In human urine, APEC O2 grew at a rate equivalent to that of UPEC strain HE300, and the transconjugant showed significantly increased growth compared to the recipient. The transconjugant also significantly outcompeted the recipient in colonization of the murine kidney. These findings suggest that APEC plasmids, such as pAPEC-O2-ColV, contribute to the pathogenesis of avian colibacillosis. Moreover, since avian E. coli and their plasmids may be transmitted to humans, evaluation of APEC plasmids as possible reservoirs of urovirulence genes for human UPEC may be warranted.
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Affiliation(s)
- Jerod A Skyberg
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
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Li Q, Skyberg JA, Fakhr MK, Sherwood JS, Nolan LK, Logue CM. Antimicrobial susceptibility and characterization of Salmonella isolates from processed bison carcasses. Appl Environ Microbiol 2006; 72:3046-9. [PMID: 16598016 PMCID: PMC1449034 DOI: 10.1128/aem.72.4.3046-3049.2006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Seventeen Salmonella enterica serovar Hadar isolates recovered from bison were found to possess a range of virulence genes and resistance to tetracycline, gentamicin, sulfamethoxazole, and streptomycin simultaneously. A 1-kb class 1 integron containing the aadA1 gene was identified in all isolates. Pulsed-field gel electrophoresis found that all isolates were closely related, indicating the possibility of cross-contamination during processing.
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Affiliation(s)
- Qiongzhen Li
- Department of Veterinary and Microbiological Sciences, 130 A Van Es Hall, North Dakota State University, Fargo, ND 58105, USA
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30
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Abstract
The purpose of this study was to develop a multiplex polymerase chain reaction (PCR) protocol useful in the virulence genotyping of Salmonella spp. with the idea that genotyping could augment current Salmonella characterization and typing methods. Seventeen genes associated with Salmonella invasion, fimbrial production, toxin production, iron transport, and intramacrophage survival were targeted by three PCR reactions. Most of these genes are required for full Salmonella virulence in a murine model, and many are also located on Salmonella pathogenicity islands (PAIs) and are associated with type III secretion systems (TTSSs). Once the success of procedures that used positive and negative control strains was verified, the genotypes of 78 Salmonella isolates incriminated in avian salmonellosis (primarily from sick, commercially reared chickens and turkeys) and 80 Salmonella isolates from apparently healthy chickens or turkeys were compared. Eleven of the 17 genes tested (invA, orgA, prgH, tolC, spaN [invJ], sipB, sitC, pagC, msgA, spiA, and iroN) were found in all of the isolates. Another (sopB) was present in all isolates from sick birds and all but one isolate from healthy birds. The remaining five genes (lpfC, cdtB, sifA, pefA, and spvB) were found in 10%-90% of the isolates from sick birds and 3.75%-90% of the healthy birds. No significant differences in the occurrence of these genes between the two groups of isolates were detected. These results suggest that these virulence genes, and presumably the PAls and TTSSs with which they are associated, are widely distributed among Salmonella isolates of birds, regardless of whether their hosts of origin have been identified as having salmonellosis.
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Affiliation(s)
- Jerod A Skyberg
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
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31
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Skyberg JA, Horne SM, Giddings CW, Wooley RE, Gibbs PS, Nolan LK. Characterizing avian Escherichia coli isolates with multiplex polymerase chain reaction. Avian Dis 2004; 47:1441-7. [PMID: 14708994 DOI: 10.1637/7030] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Colibacillosis caused by Escherichia coli infections account for significant morbidity and mortality in the poultry industry. Yet, despite the importance of colibacillosis, much about the virulence mechanisms employed by avian E. coli remains unknown. In recent years several genes have been linked to avian E. coli virulence, many of which reside on a large transmissible plasmid. In the present study, a multiplex polymerase chain reaction (PCR) protocol to detect the presence of four of these genes is described. Such a protocol may supplement current diagnostic schemes and provide a rapid means of characterizing the E. coli causing disease in poultry. The targets of this procedure included iss, the increased serum survival gene; tsh, the temperature sensitive hemagglutinin gene; cvi, the ColV immunity gene; and iucC, a gene of the aerobactin operon. Organisms, known for their possession or lack of these genes, were used as a source of the template DNA to develop the multiplex PCR protocol. Identity of the amplicons was confirmed by size, DNA:DNA hybridization with specific gene probes, and DNA sequencing. When the multiplex PCR protocol was used to characterize 10 E. coli isolates incriminated in avian colibacillosis and 10 from the feces of apparently healthy birds, nine of the isolates from apparently healthy birds contained no more than one gene, while the 10th contained all four. Also, eight of the isolates incriminated in colibacillosis contained three or more genes, while the remaining two contained two of the target genes. Interestingly, the isolates of sick birds containing only two of the targeted genes killed the least number of embryos,and the isolate of healthy birds that contained all the genes killed the most embryos amongthis group. These genes were not found among the non-E. coli isolates tested, demonstrating the procedure's specificity for E. coli. Overall, these results suggest that this protocol might be useful in characterization and study of avian E. coli.
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Affiliation(s)
- Jerod A Skyberg
- Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, ND 58105, USA
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