Experimental #H1N1pdm09 #infection in #pigs mimics #human seasonal #influenza #infections (PLoS One, abstract)

[Source: PLoS One, full page: (LINK). Abstract, edited.]

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Experimental H1N1pdm09 infection in pigs mimics human seasonal influenza infections

Theresa Schwaiger, Julia Sehl, Claudia Karte, Alexander Schäfer, Jane Hühr, Thomas C. Mettenleiter, Charlotte Schröder, Bernd Köllner, Reiner Ulrich, Ulrike Blohm

Published: September 20, 2019 / DOI: https://doi.org/10.1371/journal.pone.0222943

 

Abstract

Pigs are anatomically, genetically and physiologically comparable to humans and represent a natural host for influenza A virus (IAV) infections. Thus, pigs may represent a relevant biomedical model for human IAV infections. We set out to investigate the systemic as well as the local immune response in pigs upon two subsequent intranasal infections with IAV H1N1pdm09. We detected decreasing numbers of peripheral blood lymphocytes after the first infection. The simultaneous increase in the frequencies of proliferating cells correlated with an increase in infiltrating leukocytes in the lung. Enhanced perforin expression in αβ and γδ T cells in the respiratory tract indicated a cytotoxic T cell response restricted to the route of virus entry such as the nose, the lung and the bronchoalveolar lavage. Simultaneously, increasing frequencies of CD8αα expressing αβ T cells were observed rapidly after the first infection, which may have inhibited uncontrolled inflammation in the respiratory tract. Taking together, the results of this study demonstrate that experimental IAV infection in pigs mimics major characteristics of human seasonal IAV infections.

___

Citation: Schwaiger T, Sehl J, Karte C, Schäfer A, Hühr J, Mettenleiter TC, et al. (2019) Experimental H1N1pdm09 infection in pigs mimics human seasonal influenza infections. PLoS ONE 14(9): e0222943. https://doi.org/10.1371/journal.pone.0222943

Editor: Balaji Manicassamy, University of Iowa, UNITED STATES

Received: May 28, 2019; Accepted: September 10, 2019; Published: September 20, 2019

Copyright: © 2019 Schwaiger et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All relevant data are within the manuscript and its Supporting Information files.

Funding: This study was funded by Federal Excellence Initiative of Mecklenburg Western Pomerania and European Social Fund (ESF) Grant KoInfekt (ESF_14-BM-A55-00xx_16) to TCM.

Competing interests: The authors have declared that no competing interests exist.

Keywords: Seasonal Influenza; H1N1pdm09; Human; Pigs; Animal models.

——

Advertisements

Conjugative #delivery of #CRISPR-Cas9 for the selective #depletion of #antibiotic-resistant #enterococci (Antimicrob Agents Chemother., abstract)

[Source: Antimicrobial Agents and Chemotherapy, full page: (LINK). Abstract, edited.]

Conjugative delivery of CRISPR-Cas9 for the selective depletion of antibiotic-resistant enterococci

Marinelle Rodrigues, Sara W. McBride, Karthik Hullahalli, Kelli L. Palmer, Breck A. Duerkop

DOI: 10.1128/AAC.01454-19

 

ABSTRACT

The innovation of new therapies to combat multidrug-resistant (MDR) bacteria is being outpaced by the continued rise of MDR bacterial infections. Of particular concern are hospital-acquired infections (HAIs) recalcitrant to antibiotic therapies. The Gram-positive intestinal pathobiont Enterococcus faecalis is associated with HAIs and some strains are MDR. Therefore, novel strategies to control E. faecalis populations are needed. We previously characterized an E. faecalis Type II CRISPR-Cas system and demonstrated its utility in the sequence-specific removal of antibiotic resistance determinants. Here we present work describing the adaption of this CRISPR-Cas system into a constitutively expressed module encoded on a pheromone-responsive conjugative plasmid that efficiently transfers to E. faecalis for the selective removal of antibiotic resistance genes. Using in vitro competition assays, we show that these CRISPR-Cas-encoding delivery plasmids, or CRISPR-Cas antimicrobials, can reduce the occurrence of antibiotic resistance in enterococcal populations in a sequence-specific manner. Furthermore, we demonstrate that deployment of CRISPR-Cas antimicrobials in the murine intestine reduces the occurrence of antibiotic-resistant E. faecalis by several orders of magnitude. Finally, we show that E. faecalis donor strains harboring CRISPR-Cas antimicrobials are immune to uptake of antibiotic resistance determinants in vivo. Our results demonstrate that conjugative delivery of CRISPR-Cas antimicrobials may be adaptable for future deployment from probiotic bacteria for exact targeting of defined MDR bacteria or for precision engineering of polymicrobial communities in the mammalian intestine.

Copyright © 2019 American Society for Microbiology. All Rights Reserved.

Keywords: Antibiotics; Drugs Resistance; Enterococcus faecalis; CRISPR; Animal models.

——

#Prophylaxis of Mycobacterium #tuberculosis H37Rv #Infection in a Preclinical Mouse Model via Inhalation of Nebulized #Bacteriophage D29 (Antimicrob Agents Chemother., abstract)

[Source: Antimicrobial Agents and Chemotherapy, full page: (LINK). Abstract, edited.]

Prophylaxis of Mycobacterium tuberculosis H37Rv Infection in a Preclinical Mouse Model via Inhalation of Nebulized Bacteriophage D29

Nicholas B. Carrigy, Sasha E. Larsen, Valerie Reese, Tiffany Pecor, Melissa Harrison, Philip J. Kuehl, Graham F. Hatfull, Dominic Sauvageau, Susan L. Baldwin, Warren H. Finlay, Rhea N. Coler, Reinhard Vehring

DOI: 10.1128/AAC.00871-19

 

ABSTRACT

Globally, more people die annually from tuberculosis than from any other single infectious agent. Unfortunately, there is no commercially-available vaccine that is sufficiently effective at preventing acquisition of pulmonary tuberculosis in adults. In this study, pre-exposure prophylactic pulmonary delivery of active aerosolized anti-tuberculosis bacteriophage D29 was evaluated as an option for protection against Mycobacterium tuberculosis infection. An average bacteriophage concentration of approximately 1 PFU/alveolus was achieved in the lungs of mice using a nose-only inhalation device optimized with a dose simulation technique and adapted for use with a vibrating mesh nebulizer. Within 30 minutes of bacteriophage delivery, the mice received either a low dose (∼50-100 CFU), or an ultra-low dose (∼5-10 CFU), of M. tuberculosis H37Rv aerosol to the lungs. A prophylactic effect was observed with bacteriophage aerosol pre-treatment significantly decreasing M. tuberculosis burden in mouse lungs 24 hours and 3 weeks post-challenge (p < 0.05). These novel results indicate that a sufficient dose of nebulized mycobacteriophage aerosol to the lungs may be a valuable intervention to provide extra protection to health care professionals and other individuals at risk of exposure to M. tuberculosis.

Copyright © 2019 American Society for Microbiology. All Rights Reserved.

Keywords: Mycobacterium tuberculosis; Bacteriophages; Animal models.

——

#Mucosal #CD8+ T cell responses induced by an MCMV based #vaccine #vector confer protection against #influenza challenge (PLoS Pathog., abstract)

[Source: PLoS Pathogens, full page: (LINK). Abstract, edited.]

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Mucosal CD8+ T cell responses induced by an MCMV based vaccine vector confer protection against influenza challenge

Xiaoyan Zheng, Jennifer D. Oduro, Julia D. Boehme, Lisa Borkner, Thomas Ebensen, Ulrike Heise, Marcus Gereke, Marina C. Pils, Astrid Krmpotic, Carlos A. Guzmán, Dunja Bruder, Luka Čičin-Šain

Published: September 16, 2019 / DOI: https://doi.org/10.1371/journal.ppat.1008036 / This is an uncorrected proof.

 

Abstract

Cytomegalovirus (CMV) is a ubiquitous β-herpesvirus that establishes life-long latent infection in a high percentage of the population worldwide. CMV induces the strongest and most durable CD8+ T cell response known in human clinical medicine. Due to its unique properties, the virus represents a promising candidate vaccine vector for the induction of persistent cellular immunity. To take advantage of this, we constructed a recombinant murine CMV (MCMV) expressing an MHC-I restricted epitope from influenza A virus (IAV) H1N1 within the immediate early 2 (ie2) gene. Only mice that were immunized intranasally (i.n.) were capable of controlling IAV infection, despite the greater potency of the intraperitoneally (i.p.) vaccination in inducing a systemic IAV-specific CD8+ T cell response. The protective capacity of the i.n. immunization was associated with its ability to induce IAV-specific tissue-resident memory CD8+ T (CD8TRM) cells in the lungs. Our data demonstrate that the protective effect exerted by the i.n. immunization was critically mediated by antigen-specific CD8+ T cells. CD8TRM cells promoted the induction of IFNγ and chemokines that facilitate the recruitment of antigen-specific CD8+ T cells to the lungs. Overall, our results showed that locally applied MCMV vectors could induce mucosal immunity at sites of entry, providing superior immune protection against respiratory infections.

 

Author summary

Vaccines against influenza typically induce immune responses based on antibodies, small molecules that recognize the virus particles outside of cells and neutralize them before they infect a cell. However, influenza rapidly evolves, escaping immune recognition, and the fastest evolution is seen in the part of the virus that is recognized by antibodies. Therefore, every year we are confronted with new flu strains that are not recognized by our antibodies against the strains from previous years. The other branch of the immune system is made of killer T cells, which recognize infected cells and target them for killing. Influenza does not rapidly evolve to escape T cell killing; thus, vaccines inducing T-cell responses to influenza might provide long-term protection. We introduced an antigen from influenza into the murine cytomegalovirus (MCMV) and used it as a vaccine vector inducing killer T-cell responses of unparalleled strength. Our vector controls influenza replication and provides relief to infected mice, but only if we administered it through the nose, to activate killer T cells that will persist in the lungs close to the airways. Therefore, our data show that the subset of lung-resident killer T cells is sufficient to protect against influenza.

___

Citation: Zheng X, Oduro JD, Boehme JD, Borkner L, Ebensen T, Heise U, et al. (2019) Mucosal CD8+ T cell responses induced by an MCMV based vaccine vector confer protection against influenza challenge. PLoS Pathog 15(9): e1008036. https://doi.org/10.1371/journal.ppat.1008036

Editor: Christopher M. Snyder, Thomas Jefferson University, UNITED STATES

Received: July 17, 2019; Accepted: August 21, 2019; Published: September 16, 2019

Copyright: © 2019 Zheng et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All relevant data are within the manuscript and its Supporting Information files.

Funding: This study was supported by the European Research Council through the ERC Starting Grant 260934 to LCS and the Helmholtz Association through the Helmholtz EU Partnering Grant PIE-008 to LCS. XZ was supported by a scholarship from the Chinese Research Council. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

Keywords: Influenza A; CMV; Vaccines; Animal models.

——

Impact of #intensive #care unit supportive care on the #physiology of #Ebola virus disease in a universally lethal #NHP #model (Intensive Care Med Exp., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Intensive Care Med Exp. 2019 Sep 13;7(1):54. doi: 10.1186/s40635-019-0268-8.

Impact of intensive care unit supportive care on the physiology of Ebola virus disease in a universally lethal non-human primate model.

Poliquin G1,2,3, Funk D4, Jones S1, Tran K1, Ranadheera C1, Hagan M1,3, Tierney K1, Grolla A1, Dhaliwal A5, Bello A1, Leung A1, Nakamura C6, Kobasa D1,3, Falzarano D7, Garnett L1, Bovendo HF8, Feldmann H9, Kesselman M2, Hansen G10, Gren J1, Risi G11, Biondi M12,13, Mortimer T13, Racine T3,8, Deschambault Y1, Aminian S1, Edmonds J1, Sourette R1, Allan M1, Rondeau L1, Hadder S1, Press C1, DeGraff C1, Kucas S1, Cook BWM14, Hancock BJ2,15, Kumar A3, Soni R2, Schantz D2, McKitrick J16, Warner B1, Griffin BD1, Qiu X1,3, Kobinger GP3,8, Safronetz D1, Stein D1,3, Cutts T1, Kenny J1, Soule G1, Kozak R17, Theriault S14, Menec L1, Vendramelli R1, Higgins S1, Liu G1, Rahim NM1, Kasloff S1, Sloan A1, He S1, Tailor N1, Gray M1, Strong JE18,19,20.

Author information: 1 National Microbiology Laboratory, Public Health Agency of Canada, 1015 rue Arlington Street, Winnipeg, Manitoba, R3E 3R2, Canada. 2 Department of Pediatrics & Child Health, College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada. 3 Department of Infectious Diseases and Medical Microbiology, College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada. 4 Department of Anaesthesia and Medicine, College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada. 5 Medtronic Canada, Winnipeg, Manitoba, Canada. 6 National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, Manitoba, Canada. 7 Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, Saskatoon, Canada. 8 Centre de Recherche en Infectiologie, Centre Hospitalier Universitaire de Québec, Université Laval, Québec, Canada. 9 Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, USA. 10 Faculty of Critical Care, Royal University Hospital, Saskatoon, Saskatchewan, Canada. 11 Infectious Disease Specialists, P.C., Missoula, MT, USA. 12 Arthur Labatt Family School of Nursing, Western University, London, Ontario, Canada. 13 Child & Women’s Health Programme, Winnipeg Regional Health Authority, Winnipeg, Manitoba, Canada. 14 Cytophage Technologies, Inc., St. Boniface Hospital, Albrechtsen Research Centre, Winnipeg, Manitoba, Canada. 15 Department of Surgery, Division of Pediatric Surgery, College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada. 16 Regional Pharmacy, Winnipeg Regional Health Authority, Winnipeg, Manitoba, Canada. 17 Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada. 18 National Microbiology Laboratory, Public Health Agency of Canada, 1015 rue Arlington Street, Winnipeg, Manitoba, R3E 3R2, Canada. jim.strong@canada.ca. 19 Department of Pediatrics & Child Health, College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada. jim.strong@canada.ca. 20 Department of Infectious Diseases and Medical Microbiology, College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada. jim.strong@canada.ca.

 

Abstract

BACKGROUND:

There are currently limited data for the use of specific antiviral therapies for the treatment of Ebola virus disease (EVD). While there is anecdotal evidence that supportive care may be effective, there is a paucity of direct experimental data to demonstrate a role for supportive care in EVD. We studied the impact of ICU-level supportive care interventions including fluid resuscitation, vasoactive medications, blood transfusion, hydrocortisone, and ventilator support on the pathophysiology of EVD in rhesus macaques infected with a universally lethal dose of Ebola virus strain Makona C07.

METHODS:

Four NHPs were infected with a universally lethal dose Ebola virus strain Makona, in accordance with the gold standard lethal Ebola NHP challenge model. Following infection, the following therapeutic interventions were employed: continuous bedside supportive care, ventilator support, judicious fluid resuscitation, vasoactive medications, blood transfusion, and hydrocortisone as needed to treat cardiovascular compromise. A range of physiological parameters were continuously monitored to gage any response to the interventions.

RESULTS:

All four NHPs developed EVD and demonstrated a similar clinical course. All animals reached a terminal endpoint, which occurred at an average time of 166.5 ± 14.8 h post-infection. Fluid administration may have temporarily blunted a rise in lactate, but the effect was short lived. Vasoactive medications resulted in short-lived improvements in mean arterial pressure. Blood transfusion and hydrocortisone did not appear to have a significant positive impact on the course of the disease.

CONCLUSIONS:

The model employed for this study is reflective of an intramuscular infection in humans (e.g., needle stick) and is highly lethal to NHPs. Using this model, we found that the animals developed progressive severe organ dysfunction and profound shock preceding death. While the overall impact of supportive care on the observed pathophysiology was limited, we did observe some time-dependent positive responses. Since this model is highly lethal, it does not reflect the full spectrum of human EVD. Our findings support the need for continued development of animal models that replicate the spectrum of human disease as well as ongoing development of anti-Ebola therapies to complement supportive care.

KEYWORDS: Ebola; Fluid; Hydrocortisone; NHP; Pathophysiology; Supportive care; Vasoactives; Ventilatory support

PMID: 31520194 DOI: 10.1186/s40635-019-0268-8

Keywords: Ebola; Ebola-Makona; Intensive care; Animal models.

——

Type I and type III #interferons differ in their #adjuvant activities for #influenza #vaccines (J Virol., abstract)

[Source: Journal of Virology, full page: (LINK). Abstract, edited.]

Type I and type III interferons differ in their adjuvant activities for influenza vaccines

Liang Ye, Annette Ohnemus, Li Ching Ong, Hans Henrik Gad, Rune Hartmann, Nils Lycke, Peter Staeheli

DOI: 10.1128/JVI.01262-19

 

ABSTRACT

Type I and type III interferons (IFN) can promote adaptive immune responses in mice and improve vaccine-induced resistance to viral infections. The adjuvant effect of type III IFN (IFN-λ) specifically boosts mucosal immunity by an indirect mechanism, involving IFN-λ-induced production of thymic stromal lymphopoietin (TSLP), a cytokine that activates immune cells. To date it remained unclear whether the previously described adjuvant effect of type I IFN (IFN-α/β) would also depend on TSLP and whether type I IFN stimulates different antibody subtypes. Here we show that after infection with a live attenuated influenza virus, mice lacking functional type I IFN receptors failed to produce normal amounts of virus-specific IgG2c and IgA antibodies. In contrast, mice lacking functional IFN-λ receptors contained normal levels of virus-specific IgG2c but had reduced IgG1 and IgA antibody levels. When applied together with protein antigen, IFN-α stimulated the production of antigen-specific IgA and IgG2c to a greater extent than IgG1, irrespective of whether the mice expressed functional TSLP receptors and irrespective of whether the vaccine was applied by the intranasal or the intraperitoneal route. Taken together, these results demonstrate that the adjuvant activities of type I and type III IFNs are mechanistically distinct.

 

IMPORTANCE

Interferons can shape antiviral immune responses, but it is not understood well how they influence vaccine efficacy. We find that type I IFN preferentially promotes the production of antigen-specific IgG2c and IgA antibodies after infection with a live attenuated influenza virus or after immunization with influenza subunit vaccines. By contrast, type III IFN specifically enhances influenza virus-specific IgG1 and IgA production. The adjuvant effect of type I IFN was not dependent on TSLP which is essential for the adjuvant effect of type III IFN. Type I IFN boosted vaccine-induced antibody production after immunization by the intranasal or the intraperitoneal route, whereas type III IFN exhibited its adjuvant activity only when the vaccine was delivered by the mucosal route. Our findings demonstrate that type I and type III IFNs trigger distinct pathways to enhance the efficacy of vaccines. This knowledge might be used to design more efficient vaccines against infectious diseases.

Copyright © 2019 American Society for Microbiology. All Rights Reserved.

Keywords: Influenza A; Vaccines; Interferons; Animal models.

——

#Influenza Viruses in #Mice: Deep #Sequencing Analysis of Serial Passage and Effects of #Sialic Acid Structural #Variation (J Virol., abstract)

[Source: Journal of Virology, full page: (LINK). Abstract, edited.]

Influenza Viruses in Mice: Deep Sequencing Analysis of Serial Passage and Effects of Sialic Acid Structural Variation

Brian R. Wasik, Ian E.H. Voorhees, Karen N. Barnard, Brynn K. Alford-Lawrence, Wendy S. Weichert, Grace Hood, Aitor Nogales, Luis Martínez-Sobrido, Edward C. Holmes, Colin R. Parrish

DOI: 10.1128/JVI.01039-19

 

ABSTRACT

Influenza A viruses have regularly jumped to new host species to cause epidemics or pandemics, an evolutionary process that involves variation in the viral traits necessary to overcome host barriers and facilitate transmission. Mice are not a natural host for influenza virus, but are frequently used as models in studies of pathogenesis, often after multiple passages to achieve higher viral titers that result in clinical disease such as weight loss or death. Here we examine the processes of influenza A virus infection and evolution in mice by comparing single nucleotide variation of a human H1N1 pandemic virus, a seasonal H3N2 virus, and a H3N2 canine influenza virus during experimental passage. We also compared replication and sequence variation in wild-type mice expressing N-glycolylneuraminic acid (Neu5Gc) with that seen in mice expressing only N-acetylneuraminic acid (Neu5Ac). Viruses derived from plasmids were propagated in MDCK cells and then passaged in mice up to four times. Full genome deep sequencing of the plasmids, cultured viruses, and viruses from mice at various passages revealed only small numbers of mutational changes. The H3N2 canine influenza virus showed increases in frequency of sporadic mutations in the PB2, PA, and NA segments. The H1N1 pandemic virus grew well in mice, and while it exhibited the maintenance of some minority mutations, there was no clear evidence for adaptive evolution. The H3N2 seasonal virus did not establish in the mice. Finally, there were no clear sequence differences associated with the presence or absence of Neu5Gc.

 

SIGNIFICANCE

Mice are commonly used as a model to study the growth and virulence of influenza A viruses in mammals, but are not a natural host and have distinct sialic acid receptor profiles compared to humans. Using experimental infections with different subtypes of influenza A virus derived from different hosts we found that evolution of influenza A virus in mice did not necessarily proceed through the linear accumulation of host-adaptive mutations, that there was variation in the patterns of mutations detected in each repetition, and the mutation dynamics depended on the virus examined. In addition, variation in the viral receptor, sialic acid, did not affect influenza evolution in this model. Overall, our results show that while mice provide a useful animal model for influenza pathology, host passage evolution will vary depending on the specific virus tested.

Copyright © 2019 American Society for Microbiology. All Rights Reserved.

Keywords: Influenza A; H1N1pdm09; H3N2; Animal models.

——