#Ganglioside synthase knock-out reduces #prion disease #incubation time in mouse models (Am J Pathol., abstract)

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

Ganglioside synthase knock-out reduces prion disease incubation time in mouse models

Atsushi Kobayashi, , Zechen Qi, Taishi Shimazaki, Yoshiko Munesue, Tomomi Miyamoto, Norikazu Isoda, Hirofumi Sawa, Keisuke Aoshima, Takashi Kimura, Shirou Mohri, Tetsuyuki Kitamoto, Tadashi Yamashita, Ichiro Miyoshi

DOI: https://doi.org/10.1016/j.ajpath.2018.11.009

Accepted: November 16, 2018 – Received in revised form: November 14, 2018 – Received: September 4, 2018

 

Abstract

Localization of the abnormal and normal isoforms of prion proteins to detergent-resistant membrane microdomains, lipid rafts, is important for the conformational conversion. Lipid rafts are enriched in sialic acid–containing glycosphingolipids, namely gangliosides. Alteration in the ganglioside composition of lipid rafts can affect the localization of lipid raft–associated proteins. To investigate the role of gangliosides in the pathogenesis of prion diseases, we performed intracerebral transmission study of a scrapie prion strain Chandler and a Gerstmann-Sträussler-Scheinker syndrome prion strain Fukuoka-1 using various knock-out mouse strains ablated with ganglioside synthase gene, ie, GD2/GM2 synthase, GD3 synthase, or GM3 synthase. Following challenge with the Chandler strain, GD2/GM2 synthase knock-out mice showed 20% reduction of incubation time, reduced prion protein deposition in the brain with attenuated glial reactions, and reduced localization of prion proteins to lipid rafts. These results raise the possibility that the gangliosides may have an important role in prion disease pathogenesis by affecting the localization of prion proteins to lipid rafts.

Funding: Supported by Grants-in-Aid for Scientific Research from JSPS (18K05963; A.K.), The Ichiro Kanehara Foundation (A.K.), The Suhara Memorial Foundation (A.K.), and The Kato Memorial Trust for Nambyo Research (A.K.).

Disclosures: None declared.

© 2018 Published by Elsevier Inc. on behalf of the American Society for Investigative Pathology.

Keywords: Prions; Scrapie; Gangliosides; Animal models.

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A YF– #Zika #chimeric virus #vaccine candidate protects against Zika #infection and #congenital malformations in mice (npj Vaccines, abstract)

[Source: npj Vaccines, full page: (LINK). Abstract, edited.]

Article | OPEN | Published: 13 December 2018

A yellow fever–Zika chimeric virus vaccine candidate protects against Zika infection and congenital malformations in mice

Dieudonné B. Kum,  Niraj Mishra, Robbert Boudewijns, Ivan Gladwyn-Ng, Christian Alfano, Ji Ma, Michael A. Schmid, Rafael E. Marques, Dominique Schols, Suzanne Kaptein, Laurent Nguyen, Johan Neyts & Kai Dallmeier

npj Vaccines, volume 3, Article number: 56 (2018)

 

Abstract

The recent Zika virus (ZIKV) epidemic in the Americas led to an intense search for therapeutics and vaccines. Here we report the engineering of a chimeric virus vaccine candidate (YF-ZIKprM/E) by replacing the antigenic surface glycoproteins and the capsid anchor of YFV-17D with those of a prototypic Asian lineage ZIKV isolate. By intracellular passaging, a variant with adaptive mutations in the E protein was obtained. Unlike YFV-17D, YF-ZIKprM/E replicates poorly in mosquito cells. Also, YF-ZIKprM/E does not cause disease nor mortality in interferon α/β, and γ receptor KO AG129 mice nor following intracranial inoculation of BALB/c pups. A single dose as low as 1 × 102 PFU results, as early as 7 days post vaccination, in seroconversion to neutralizing antibodies and confers full protection in AG129 mice against stringent challenge with a lethal inoculum (105 LD50) of either homologous or heterologous ZIKV strains. Induction of multi-functional CD4+ and CD8+T cell responses against ZIKV structural and YFV-17D non-structural proteins indicates that cellular immunity may also contribute to protection. Vaccine immunogenicity and protection was confirmed in other mouse strains, including after temporal blockade of interferon-receptors in wild-type mice to facilitate ZIKV replication. Vaccination of wild-type NMRI dams with YF-ZIKprM/E results in complete protection of foetuses against brain infections and malformations following a stringent intraplacental challenge with an epidemic ZIKV strain. The particular characteristic of YF-ZIKprM/E in terms of efficacy and its marked attenuation in mice warrants further exploration as a vaccine candidate.

Keywords: Zika Virus; Vaccines; Animal models.

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#Equine-origin #immunoglobulin fragments protects nonhuman #primates from #Ebola virus disease (J Virol., abstract)

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

Equine-origin immunoglobulin fragments protects nonhuman primates from Ebola virus disease

Hualei Wang, Gary Wong, Wenjun Zhu, Shihua He, Yongkun Zhao, Feihu Yan, Md Niaz Rahim, Yuhai Bi, Zirui Zhang, Keding Cheng, Hongli Jin, Zengguo Cao, Xuexing Zheng, Weiwei Gai,Jieying Bai, Weijin Chen, Yong Zou, Yuwei Gao, George F Gao, Songtao Yang, Xianzhu Xia, Xiangguo Qiu

DOI: 10.1128/JVI.01548-18

 

ABSTRACT

Ebola virus (EBOV) infections result in aggressive hemorrhagic fever in humans with fatality rates reaching 90%, with no licensed, specific therapeutics to treat ill patients. Advances over the past 5 years have firmly established monoclonal antibody (mAb)-based products as the most promising therapeutics for treating EBOV infections, but production is costly, quantities are limited, and thus mAbs are not the best candidates for mass use in the case of an epidemic. To address this need, we generated EBOV-specific polyclonal immunoglobulin fragments F(ab’)2 from horses hyperimmunized with an EBOV vaccine. The F(ab’)2 was found to potently neutralize West and Central African EBOV in vitro. Treatment of nonhuman primates (NHPs) with seven doses of 100mg/kg F(ab’)2 beginning at 3 or 5 days post-infection (dpi) resulted in 100% survival. Notably, NHPs that initiated treatment at 5 dpi were already highly viremic with observable signs of EBOV disease, demonstrating that F(ab’)2 was still effective as a therapeutic even in symptomatic patients. These results show that F(ab’)2 should be accelerated for clinical testing in preparation of future EBOV outbreaks and epidemics.

 

IMPORTANCE

Ebola is one of the deadliest viruses to humans. It has been over 40 years since Ebola was first reported, but no cure is available. Research breakthroughs over the last 5 years have shown that monoclonal antibodies (mAbs) constitute an effective therapy for Ebola. However, mAbs are expensive, difficult to produce in large amounts and therefore may only play a limited role during an epidemic. A cheaper alternative is required, especially since Ebola is endemic in several third-world countries with limited medical resources. Here, we used a standard protocol to produce large amounts of antisera fragments (F(ab’)2) from horses vaccinated with an Ebola vaccine, and tested its protectiveness in monkeys. We showed that F(ab’)2 was effective in 100% of monkeys even after these animals were visibly ill with Ebola. Thus, F(ab’)2 could be a very good option for large-scale treatments of patients and should be advanced to clinical testing.

© Crown copyright 2018. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license.

Keywords: Ebola; Serotherapy; Animal models.

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Co-localization of #MERS #Coronavirus and #DPP4 in the #respiratory tract and #lymphoid tissues of #pigs and #llamas (Transbound Emerg Dis., abstract)

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

Transbound Emerg Dis. 2018 Dec 6. doi: 10.1111/tbed.13092. [Epub ahead of print]

Co-localization of Middle East respiratory syndrome coronavirus (MERS-CoV) and dipeptidyl peptidase-4 in the respiratory tract and lymphoid tissues of pigs and llamas.

Te N1, Vergara-Alert J1, Lehmbecker A2, Pérez M1, Haagmans BL3, Baumgärtner W2, Bensaid A1, Segalés J4,5.

Author information: 1 IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain. 2 Department of Pathology, University of Veterinary Medicine, Hannover, Germany. 3 Department of Viroscience, Erasmus Medical Center, 3015 CN, Rotterdam, The Netherlands. 4 UAB, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain. 5 Departament de Sanitat i Anatomia Animals, Facultat de Veterinària, UAB, 08193, Bellaterra, Barcelona, Spain.

 

Abstract

The present study investigated the co-localization of the Middle East respiratory syndrome coronavirus (MERS-CoV) and its receptor dipeptidyl peptidase-4 (DPP4) across respiratory and lymphoid organs of experimentally MERS-CoV infected pigs and llamas by immunohistochemistry (IHC). Also, scanning electron microscopy (SEM) was performed to assess the ciliary integrity of respiratory epithelial cells in both species. In pigs, on day 2 post-inoculation (p.i.), DPP4-MERS-CoV co-localization was detected in medial turbinate epithelium. On day 4 p.i., the virus/receptor co-localized in frontal and medial turbinate epithelial cells in pigs, and epithelial cells distributed unevenly through the whole nasal cavity and in the cervical lymph node in llamas. MERS-CoV viral nucleocapsid was mainly detected in upper respiratory tract sites on days 2 and 4 p.i. in pigs and day 4 p.i. in llamas. No MERS-CoV was detected on day 24 p.i. in any tissue by IHC. While pigs showed severe ciliary loss in the nasal mucosa both on days 2 and 4 p.i. and moderate loss in the trachea on days 4 and 24 p.i., ciliation of respiratory organs in llamas was not significantly affected. Obtained data confirm the role of DPP4 for MERS-CoV entry in respiratory epithelial cells of llamas. Notably, several nasal epithelial cells in pigs were found to express viral antigen but not DPP4, suggesting the possible existence of other molecule/s facilitating virus entry or down regulation of DPP4 upon infection.

This article is protected by copyright. All rights reserved.

KEYWORDS: Middle East respiratory syndrome coronavirus (MERS-CoV); dipeptidyl peptidase-4 (DPP4); immunohistochemistry; llama; pig; scanning electron microscopy

PMID: 30520548 DOI: 10.1111/tbed.13092

Keywords: MERS-CoV; Pigs; Llamas; Animal models; Viral pathogenesis.

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#Persistence of #Lassa Virus Associated With Severe Systemic #Arteritis in Convalescing Guinea Pigs (Cavia porcellus) (J Infect Dis., abstract)

[Source: The Journal of Infectious Diseases, full page: (LINK). Abstract, edited.]

Persistence of Lassa Virus Associated With Severe Systemic Arteritis in Convalescing Guinea Pigs (Cavia porcellus)

David X Liu, Donna L Perry, Lisa Evans DeWald, Yingyun Cai, Katie R Hagen, Timothy K Cooper, Louis M Huzella, Randy Hart, Amanda Bonilla, John G Bernbaum, Krisztina B Janosko, Ricky Adams, Reed F Johnson, Jens H Kuhn, Matthias J Schnell, Ian Crozier, Peter B Jahrling, Juan C de la Torre

The Journal of Infectious Diseases, jiy641, https://doi.org/10.1093/infdis/jiy641

Published: 05 December 2018

 

Abstract

Lassa fever (LF) survivors develop various clinical manifestations including polyserositis, myalgia, epididymitis, and hearing loss weeks to months after recovery from acute infection. We demonstrate a systemic lymphoplasmacytic and histiocytic arteritis and periarteritis in guinea pigs more than 2 months after recovery from acute Lassa virus (LASV) infection. LASV was detected in the arterial tunica media smooth muscle cells by immunohistochemistry, in situhybridization, and transmission electron microscopy. Our results suggest that the sequelae of LASV infection may be due to virus persistence resulting in systemic vascular damage. These findings shed light on the pathogenesis of LASV sequelae in convalescent human survivors.

arteritis; periarteritis, guinea pig, Lassa virus persistent infection; mammarenavirus; Arenaviridae; viral hemorrhagic fever; arenavirus; BSL-4

Issue Section: Brief Report

Keywords: Arenavirus; Mammarenavirus; Lassa Fever; Animal models.

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Identification and characterization of GLDC as host #susceptibility #gene to severe #influenza (EMBO Mol Med., abstract)

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

EMBO Mol Med. 2018 Nov 28. pii: e9528. doi: 10.15252/emmm.201809528. [Epub ahead of print]

Identification and characterization of GLDC as host susceptibility gene to severe influenza.

Zhou J1,2,3, Wang D2, Wong BH2, Li C2, Poon VK2, Wen L2, Zhao X2, Chiu MC2, Liu X2, Ye Z2, Yuan S2, Sze KH2, Chan JF1,2,3,4,5,6, Chu H1,2,3, To KK1,2,3,4,5,6, Yuen KY7,2,3,4,5,6.

Author information: 1 State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Pokfulam, Hong Kong. 2 Department of Microbiology, The University of Hong Kong, Pokfulam, Hong Kong. 3 Research Centre of Infection and Immunology, The University of Hong Kong, Pokfulam, Hong Kong. 4 Carol Yu Centre for Infection, The University of Hong Kong, Pokfulam, Hong Kong. 5 The Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The University of Hong Kong, Pokfulam, Hong Kong. 6 Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China. 7 State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Pokfulam, Hong Kong kyyuen@hku.hk.

 

Abstract

Glycine decarboxylase (GLDC) was prioritized as a candidate susceptibility gene to severe influenza in humans. The higher expression of GLDC derived from genetic variations may confer a higher risk to H7N9 and severe H1N1 infection. We sought to characterize GLDC as functional susceptibility gene that GLDC may intrinsically regulate antiviral response, thereby impacting viral replication and disease outcome. We demonstrated that GLDC inhibitor AOAA and siRNA depletion boosted IFNβ- and IFN-stimulated genes (ISGs) in combination with PolyI:C stimulation. GLDC inhibition and depletion significantly amplified antiviral response of type I IFNs and ISGs upon viral infection and suppressed the replication of H1N1 and H7N9 viruses. Consistently, GLDC overexpression significantly promoted viral replication due to the attenuated antiviral responses. Moreover, GLDC inhibition in H1N1-infected BALB/c mice recapitulated the amplified antiviral response and suppressed viral growth. AOAA provided potent protection to the infected mice from lethal infection, comparable to a standard antiviral against influenza viruses. Collectively, GLDC regulates cellular antiviral response and orchestrates viral growth. GLDC is a functional susceptibility gene to severe influenza in humans.

KEYWORDS: GLDC ; antiviral response; genetic susceptibility; severe influenza; viral replication

PMID: 30498026 DOI: 10.15252/emmm.201809528

Keywords: Influenza A; Genetics.

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Broadened #immunity against #influenza by #vaccination with computationally designed influenza virus N1 #neuraminidase constructs (npj Vaccines, abstract)

[Source: npj Vaccines, full page: (LINK). Abstract, edited.]

Article | OPEN | Published: 29 November 2018

Broadened immunity against influenza by vaccination with computationally designed influenza virus N1 neuraminidase constructs

E. R. Job, T. Ysenbaert, A. Smet, I. Christopoulou, T. Strugnell, E. O. Oloo, R. P. Oomen, H. Kleanthous, T. U. Vogel & X. Saelens

npj Vaccines, volume 3, Article number: 55 (2018)

 

Abstract

Split inactivated influenza vaccines remain one of the primary preventative strategies against severe influenza disease in the population. However, current vaccines are only effective against a limited number of matched strains. The need for broadly protective vaccines is acute due to the high mutational rate of influenza viruses and multiple strain variants in circulation at any one time. The neuraminidase (NA) glycoprotein expressed on the influenza virion surface has recently regained recognition as a valuable vaccine candidate. We sought to broaden the protection provided by NA within the N1 subtype by computationally engineering consensus NA sequences. Three NA antigens (NA5200, NA7900, NA9100) were designed based on sequence clusters encompassing three major groupings of NA sequence space; (i) H1N1 2009 pandemic and Swine H1N1, (ii) historical seasonal H1N1 and (iii) H1N1 viruses ranging from 1933 till current times. Recombinant NA proteins were produced as a vaccine and used in a mouse challenge model. The design of the protein dictated the protection provided against the challenge strains. NA5200 protected against H1N1 pdm09, a Swine isolate from 1998 and NIBRG-14 (H5N1). NA7900 protected against all seasonal H1N1 viruses tested, and NA9100 showed the broadest range of protection covering all N1 viruses tested. By passive transfer studies and serological assays, the protection provided by the cluster-based consensus (CBC) designs correlated to antibodies capable of mediating NA inhibition. Importantly, sera raised to the consensus NAs displayed a broader pattern of reactivity and protection than naturally occurring NAs, potentially supporting a predictive approach to antigen design.

Keywords: H1N1; Influenza A; Vaccines; Animal Models.

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