Cross-genotype protection of live-attenuated #vaccine candidate for #SFTS virus in a #ferret model (Proc Natl Acad Sci USA, abstract)

[Source: Proceedings of the National Academy of Sciences of the United States of America, full page: (LINK). Abstract, edited.]

Cross-genotype protection of live-attenuated vaccine candidate for severe fever with thrombocytopenia syndrome virus in a ferret model

Kwang-Min Yu, Su-Jin Park, Min-Ah Yu, Young-Il Kim, Younho Choi, Jae U. Jung, Benjamin Brennan, and Young Ki Choi

PNAS first published December 9, 2019 / DOI: https://doi.org/10.1073/pnas.1914704116

Edited by Peter Palese, Icahn School of Medicine at Mount Sinai, New York, NY, and approved November 5, 2019 (received for review August 23, 2019)

 

Significance

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging viral pathogen discovered in 2009. The virus is present in countries of East Asia and is transmitted through the bite of an infected Haemaphysalis longicornis tick. SFTSV disease is associated with high morbidity and is often fatal. Despite the incidence of disease, no antiviral therapy or vaccine has been approved for use. Here, we report and assess 2 live attenuated viruses as vaccine candidates in our recently described ferret model of infection. We show that the viruses caused no clinical disease or mortality in healthy animals. Immunized animals mounted a robust humoral immune response to a single dose of virus, and this response protected the animals from a lethal challenge.

 

Abstract

Severe fever with thrombocytopenia syndrome (SFTS) virus (SFTSV) is an emerging tick-borne virus classified within the Banyangvirus genus. SFTS disease has been reported throughout East Asia since 2009 and is characterized by high fever, thrombocytopenia, and leukopenia and has a 12 to 30% case fatality rate. Due to the recent emergence of SFTSV, there has been little time to conduct research into preventative measures aimed at combatting the virus. SFTSV is listed as one of the World Health Organization’s Prioritized Pathogens for research into antiviral therapeutics and vaccine development. Here, we report 2 attenuated recombinant SFTS viruses that induce a humoral immune response in immunized ferrets and confer complete cross-genotype protection to lethal challenge. Animals infected with rHB29NSsP102A or rHB2912aaNSs (both genotype D) had a reduced viral load in both serum and tissues and presented without high fever, thrombocytopenia, or mortality associated with infection. rHB29NSsP102A- or rHB2912aaNSs-immunized animals developed a robust anti-SFTSV immune response against cross-genotype isolates of SFTSV. This immune response was capable of neutralizing live virus in a focus-reduction neutralization test (FRNT) and was 100% protective against a cross-genotype lethal challenge with the CB1/2014 strain of SFTSV (genotype B). Thus, using our midsized, aged ferret infection model, we demonstrate 2 live attenuated vaccine candidates against the emerging pathogen SFTSV.

SFTS – emerging banyangvirus – live attenuated vaccine – ferret model – bunyavirus

Keywords: Bunyavirus; Banyangvirus; SFTS; Vaccines; Animal models.

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Fluorescent #CCHF virus illuminates tissue #tropism patterns and identifies early mononuclear phagocytic cell targets in IFNAR-/- mice (PLOS Pathog., abstract)

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

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Fluorescent Crimean-Congo hemorrhagic fever virus illuminates tissue tropism patterns and identifies early mononuclear phagocytic cell targets in IFNAR-/- mice

Stephen R. Welch, Jana M. Ritter, Anita K. McElroy, Jessica R. Harmon, JoAnn D. Coleman-McCray, Florine E. M. Scholte, Gary P. Kobinger, Éric Bergeron, Sherif R. Zaki, Stuart T. Nichol, Jessica R. Spengler , Christina F. Spiropoulou

___

Published: December 2, 2019 / DOI: https://doi.org/10.1371/journal.ppat.1008183 / This is an uncorrected proof.

 

Abstract

Crimean-Congo hemorrhagic fever virus (CCHFV, order Bunyavirales, family Nairoviridae, genus Orthonairovirus) is the tick-borne etiological agent of Crimean-Congo hemorrhagic fever (CCHF) in humans. Animals are generally susceptible to CCHFV infection but refractory to disease. Small animal models are limited to interferon-deficient mice, that develop acute fatal disease following infection. Here, using a ZsGreen1- (ZsG) expressing reporter virus (CCHFV/ZsG), we examine tissue tropism and dissemination of virus in interferon-α/β receptor knock-out (Ifnar-/-) mice. We demonstrate that CCHFV/ZsG retains in vivo pathogenicity comparable to wild-type virus. Interestingly, despite high levels of viral RNA in all organs assessed, 2 distribution patterns of infection were observed by both fluorescence and immunohistochemistry (IHC), corresponding to the permissiveness of organ tissues. To further investigate viral dissemination and to temporally define cellular targets of CCHFV in vivo, mice were serially euthanized at different stages of disease. Flow cytometry was used to characterize CCHFV-associated alterations in hematopoietic cell populations and to classify infected cells in the blood, lymph node, spleen, and liver. ZsG signal indicated that mononuclear phagocytic cells in the lymphatic tissues were early targets of infection; in late-stage infection, overall, the highest levels of signal were detected in the liver, and ZsG was found in both antigen-presenting and lymphocyte cell populations.

 

Author summary

Human infection by tick-borne Crimean-Congo hemorrhagic fever virus (CCHFV) can result in severe disease with up to 30% case fatality rates. While CCHFV is known to be hepatotropic, the presence and implications of virus in other tissues are less clear. Furthermore, to date, early cellular targets of infection in a CCHFV disease model have not been investigated in detail. Here, using a recombinant reporter CCHFV expressing the fluorescent protein ZsGreen1 (ZsG; CCHFV/ZsG) in interferon-α/β receptor knock-out (Ifnar-/-) mice, which develop acute fatal disease following infection, we investigate both cellular and tissue targets of infection. Importantly, we find that CCHFV/ZsG infection demonstrated comparable pathogenicity to wild-type virus in Ifnar-/- mice. We used in situ visualization of fluorescent signal in tissues to assess viral dissemination throughout the course of infection, and found robust viral signal in reproductive tissues, previously unrecognized as sites of CCHFV infection. We also used flow cytometry to detect intracellular fluorescent signal, and identified initial target cells of CCHFV infection as macrophage and monocyte populations in lymphatic tissues. These findings support a central role of immune cells in early virus dissemination, and a need for further investigations into reproductive tract involvement in human CCHFV infection.

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Citation: Welch SR, Ritter JM, McElroy AK, Harmon JR, Coleman-McCray JD, Scholte FEM, et al. (2019) Fluorescent Crimean-Congo hemorrhagic fever virus illuminates tissue tropism patterns and identifies early mononuclear phagocytic cell targets in IFNAR-/- mice. PLoS Pathog 15(12): e1008183. https://doi.org/10.1371/journal.ppat.1008183

Editor: Veronika von Messling, Federal Ministry of Education and Research, GERMANY

Received: June 4, 2019; Accepted: November 1, 2019; Published: December 2, 2019

This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

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

Funding: This work was partially supported by an appointment to the Research Participation Program at the Centers for Disease Control and Prevention administered by the Oak Ridge Institute for Science and Education through an interagency agreement between the U.S. Department of Energy and CDC (S.R.W.), by a CDC foundation project funded by NIAID grant R01AI109008 (E.B.), and by CDC Emerging Infectious Disease Research Core Funds. 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: CCHF; Viral pathogenesis.

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#Đakrông virus, a novel #mobatvirus (#Hantaviridae) harbored by the Stoliczka’s Asian trident #bat (Aselliscus stoliczkanus) in #Vietnam (Sci Rep., abstract)

[Source: Scientific Reports, full page: (LINK). Abstract, edited.]

Article | OPEN | Published: 15 July 2019

Đakrông virus, a novel mobatvirus (Hantaviridae) harbored by the Stoliczka’s Asian trident bat (Aselliscus stoliczkanus) in Vietnam

Satoru Arai, Keita Aoki, Nguyễn Trường Sơn, Vương Tân Tú, Fuka Kikuchi, Gohta Kinoshita, Dai Fukui, Hoàng Trung Thành, Se Hun Gu, Yasuhiro Yoshikawa, Keiko Tanaka-Taya, Shigeru Morikawa, Richard Yanagihara & Kazunori Oishi

Scientific Reports, volume 9, Article number: 10239 (2019)

 

Abstract

The recent discovery of genetically distinct shrew- and mole-borne viruses belonging to the newly defined family Hantaviridae (order Bunyavirales) has spurred an extended search for hantaviruses in RNAlater®-preserved lung tissues from 215 bats (order Chiroptera) representing five families (Hipposideridae, Megadermatidae, Pteropodidae, Rhinolophidae and Vespertilionidae), collected in Vietnam during 2012 to 2014. A newly identified hantavirus, designated Đakrông virus (DKGV), was detected in one of two Stoliczka’s Asian trident bats (Aselliscus stoliczkanus), from Đakrông Nature Reserve in Quảng Trị Province. Using maximum-likelihood and Bayesian methods, phylogenetic trees based on the full-length S, M and L segments showed that DKGV occupied a basal position with other mobatviruses, suggesting that primordial hantaviruses may have been hosted by ancestral bats.

Keywords: Mobatvirus; Hantavirus; Bats; Bunyavirus; Dakrong virus; Vietnam.

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SNX11 Identified as an Essential #Host Factor for #SFTS Virus #Infection by #CRISPR Knockout Screening (Virol Sin., abstract)

[Source: Virologica Sinica, full page: (LINK). Abstract, edited.]

SNX11 Identified as an Essential Host Factor for SFTS Virus Infection by CRISPR Knockout Screening

Authors: Tiezhu Liu, Jiajia Li, Yang Liu, Yuanyuan Qu, Aqian Li, Chuan Li, Quanfu Zhang,Wei Wu, Jiandong Li, Yan Liu, Dexin Li, Shiwen Wang, Mifang Liang

Research Article / First Online: 18 June 2019

 

Abstract

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a highly pathogenic tick-borne bunyavirus that causes lethal infectious disease and severe fever with thrombocytopenia syndrome (SFTS) in humans. The molecular mechanisms and host cellular factors required for SFTSV infection remain uncharacterized. Using a genome-wide CRISPR-based screening strategy, we identified a host cellular protein, sorting nexin 11 (SNX11) which is involved in the intracellular endosomal trafficking pathway, as an essential cell factor for SFTSV infection. An SNX11-KO HeLa cell line was established, and SFTSV replication was significantly reduced. The glycoproteins of SFTSV were detected and remained in later endosomal compartments but were not detectable in the endoplasmic reticulum (ER) or Golgi apparatus. pH values in the endosomal compartments of the SNX11-KO cells increased compared with the pH of normal HeLa cells, and lysosomal-associated membrane protein 1 (LAMP1) expression was significantly elevated in the SNX11-KO cells. Overall, these results indicated that penetration of SFTSV from the endolysosomes into the cytoplasm of host cells was blocked in the cells lacking SNX11. Our study for the first time provides insight into the important role of the SNX11 as an essential host factor in the intracellular trafficking and penetrating process of SFTSV infection via potential regulation of viral protein sorting, membrane fusion, and other endocytic machinery.

Keywords: CRISPR – screen – Severe fever with thrombocytopenia syndrome virus (SFTSV) – Host factor – Sorting nexin 11 (SNX11)

Electronic supplementary material

The online version of this article ( https://doi.org/10.1007/s12250-019-00141-0) contains supplementary material, which is available to authorized users.

 

Notes

Acknowledgements

This work was supported by the National Key Project for Infectious Disease from the Ministry of Science and Technology (Grant No. 2018ZX10711-001).

Author Contributions

TL performed the experiments and wrote the paper; Jiajia Li, YL, and YQ performed the experiments; AL, QZ, CL, WW, YL, and Jiandong Li contributed reagents/materials/analysis tools. Jiajia Li, TL, ML, YL, Jiandong Li, and DL analyzed and discussed the data. ML and SW designed the project and edited the manuscript. All authors read and approved the final manuscript.

 

Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflict of interest.

Animal and Human Rights Statement

This article does not contain any studies with human or animal subjects performed by any of the authors.

Keywords: SFTS virus; Bunyavirus; CRISPR; Viral pathogenesis.

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Preexisting #chronic #conditions for #fatal #outcome among #SFTS patients: An observational Cohort Study (PLoS Negl Trop Dis., abstract)

[Source: PLoS Neglected Tropical Diseases, full page: (LINK). Abstract, edited.]

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Preexisting chronic conditions for fatal outcome among SFTS patients: An observational Cohort Study

Shao-Fei Zhang , Zhen-Dong Yang , Mao-Lin Huang , Zhi-Bo Wang, Yuan-Yuan Hu, Dong Miao, Ke Dai, Juan Du, Ning Cui, Chun Yuan, Hao Li, Xiao-Kun Li, Xiao-Ai Zhang,  [ … ], Wei Liu

Published: May 28, 2019 / DOI: https://doi.org/10.1371/journal.pntd.0007434 / This is an uncorrected proof.

 

Abstract

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease that is caused by a novel bunyavirus SFTSV. Currently our knowledge of the host-related factors that influence the pathogenesis of disease is inadequate to allow prediction of fatal outcome. Here we conducted a prospective study of the largest database on the SFTS patients, to identify the presence of comorbidities in SFTS, and estimate their effect on the fatal outcome. Among 2096 patients eligible for inclusion, we identified nine kinds of comorbidities, from which hyperlipidemia (12.2%; 95% CI: 10.8%–13.6%), hypertension (11.0%; 95% CI: 9.6%–12.3%), chronic viral hepatitis (CVH) (9.3%; 95% CI: 8.1%–10.5%), and diabetes mellitus (DM) (6.8%; 95% CI: 5.7%–7.9%) were prevalent. Higher risk of death was found in patients with DM (adjusted OR = 2.304; 95% CI: 1.520–3.492; P<0.001), CVH (adjusted OR = 1.551; 95% CI: 1.053–2.285; P = 0.026) and chronic obstructive pulmonary diseases (COPD) (adjusted OR = 2.170; 95% CI: 1.215–3.872; P = 0.009) after adjusting for age, sex, delay from disease onset to admission and treatment regimens. When analyzing the comorbidities separately, we found that the high serum glucose could augment diseases severity. Compared to the group with max glucose < 7.0 mmol/L, patients with glucose between 7.0–11.1 mmol/L and glucose ≥11.1 mmol/L conferred higher death risk, with the adjusted OR to be 1.467 (95% CI: 1.081–1.989; P = 0.014) and 3.443 (95% CI: 2.427–4.884; P<0.001). Insulin therapy could effectively reduce the risk of severe outcome in DM patients with the adjusted OR 0.146 (95% CI: 0.058–0.365; P<0.001). For CVH patients, severe damage of liver and prolongation of blood coagulation time, as well as high prevalence of bleeding phenotype were observed. These data supported the provocative hypothesis that treating SFTS related complications can attain potentially beneficial effects on SFTS.

 

Author summary

SFTS now brings about a substantial global public health concern. Preexisting chronic conditions were thought to increase risk of severe SFTSV infections, however with sparse data mining efforts. In this study, we quantified the frequency of chronic comorbidities in SFTS, estimated their contribution to disease severity, and separately evaluated the effect from diabetes mellitus and chronic viral hepatitis on resulting in fatal outcome.

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Citation: Zhang S-F, Yang Z-D, Huang M-L, Wang Z-B, Hu Y-Y, Miao D, et al. (2019) Preexisting chronic conditions for fatal outcome among SFTS patients: An observational Cohort Study. PLoS Negl Trop Dis 13(5): e0007434. https://doi.org/10.1371/journal.pntd.0007434

Editor: Patricia V. Aguilar, University of Texas Medical Branch, UNITED STATES

Received: January 8, 2019; Accepted: May 2, 2019; Published: May 28, 2019

Copyright: © 2019 Zhang 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: WL is supported by the China Mega-Project for Infectious Diseases (No. 2018ZX10713002), National Natural Science Foundation of China (No. 81825019 and 81621005), and the Talent Program of Science and Technology of Beijing (No. Z181100006318008, Z171100001117089). HL is supported by National Natural Science Foundation of China (No. 81472005). QBL is supported by National Natural Science Foundation of China (No. 81703274) and Peking University Medicine Seed Fund for Interdisciplinary Research (BMU2018MX009). 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: Bunyavirus; SFTS.

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Rescue of infectious recombinant #Hazara #nairovirus from cDNA reveals the nucleocapsid protein DQVD caspase #cleavage motif performs an essential role other than cleavage (J Virol., abstract)

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

Rescue of infectious recombinant Hazara nairovirus from cDNA reveals the nucleocapsid protein DQVD caspase cleavage motif performs an essential role other than cleavage.

J. Fuller, R. A. Surtees, G.S. Slack, J. Mankouri, R. Hewson, J. N. Barr

DOI: 10.1128/JVI.00616-19

 

ABSTRACT

The Nairoviridae family of the Bunyavirales order comprises tick-borne tri-segmented negative strand RNA viruses, with several members associated with serious or fatal disease in humans and animals. A notable member is Crimean-Congo hemorrhagic fever virus (CCHFV), which is the most widely-distributed tick-borne pathogen, and associated with devastating human disease with case/fatality rates averaging 30%. Hazara virus (HAZV) is closely-related to CCHFV, sharing the same serogroup and many structural, biochemical and cellular properties. To improve understanding of HAZV and nairovirus multiplication cycles, we developed for the first time a rescue system permitting efficient recovery of infectious HAZV from cDNA. This system now allows reverse genetics analysis of nairoviruses without the need for high biosafety containment, as is required for CCHFV. We used this system to test the importance of a DQVD caspase cleavage site exposed on the apex of the HAZV nucleocapsid protein arm domain that is cleaved during HAZV infection, and for which the equivalent DEVD sequence was recently shown to be important for CCHFV growth in tick but not mammalian cells. Infectious HAZV bearing an un-cleavable DQVE sequence was rescued and exhibited equivalent growth parameters to wild-type in both mammalian and tick cells, showing this site was dispensable for virus multiplication. In contrast, substitution of the DQVD motif with the similarly un-cleavable AQVA sequence could not be rescued despite repeated efforts. Together, this work highlights the importance of this caspase cleavage site in the HAZV lifecycle, but reveals the DQVD sequence performs a critical role aside from caspase cleavage.

 

IMPORTANCE

Hazara virus is classified within the Nairoviridae family along with Crimean-Congo hemorrhagic fever virus (CCHFV), which is one of the most lethal human pathogens in existence, requiring the highest biosafety level (BSL) containment (BSL-4). In contrast, HAZV is not associated with human disease and thus can be studied using less-restrictive BSL-2 protocols. Here, we report a system able to rescue Hazara virus (HAZV) from cDNAs, thus permitting reverse genetic interrogation of the HAZV replication cycle. We used this system to examine the role of a caspase cleavage site, DQVD, within the HAZV nucleocapsid protein that is also conserved in CCHFV. By engineering mutant viruses, we showed caspase cleavage at this site was not required for productive infection, and furthermore that this sequence performs a critical role in the virus lifecycle aside from caspase cleavage. This system will accelerate nairovirus research due to its efficiency and utility under amenable BSL-2 protocols.

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

Keywords: Bunyavirus; Hazara virus; CCHF virus; Nairovirus.

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#Aporé virus, a novel #mammarenavirus (#Bunyavirales: #Arenaviridae) related to highly pathogenic virus from South #America (Mem Inst Oswaldo Cruz, abstract)

[Source: Memoria do Institutos Oswaldo Cruz, full page: (LINK). Abstract, edited.]

Aporé virus, a novel mammarenavirus (Bunyavirales: Arenaviridae) related to highly pathogenic virus from South America

[ACCEPTED ARTICLES / PRELIMINARY VERSION]

Jorlan Fernandes1,+, Alexandro Guterres1, Renata Carvalho de Oliveira1, Rodrigo Jardim2, Alberto Martín Rivera Dávila2, Roger Hewson3, Elba Regina Sampaio de Lemos1

1 Laboratório de Hantaviroses e Rickettsioses, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro – RJ, Brasil; 2 Laboratório de Biologia Computacional e Sistemas, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro – RJ, Brasil; 3 National Infection Service, Public Health England, Salisbury, United Kingdom

DOI: 10.1590/0074-02760180586

 

ABSTRACT

Here, we report the complete genome sequence of the Aporé virus (Bunyavirales: Arenaviridae), obtained from a wild rodent Oligoryzomys mattogrossae captured in Mato Grosso do Sul state, Brazil. The genome of this virus showed strong similarity to highly pathogenic mammarenavirus from South America.

key words: Oligoryzomys – mattogrossae rodent mammarenavirus – arenavirus – Aporé virus

Financial support: FIOCRUZ, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – CAPES and Conselho Nacional para o Desenvolvimento Científico e Tecnológico (CNPq), grant number 404762/2016-6.

+ Corresponding author: jorlan@ioc.fiocruz.br

Received 14 December 2018  – Accepted 29 April 2019

Keywords: Mammarenavirus; Bunyavirus; Arenavirus; Aporé virus; Brazil.

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#Environmental #Risk #Factors and Geographic #Distribution of #SFTS in #Jiangsu Province, #China (Vector Borne Zoo Dis., abstract)

[Source: Vector Borne and Zoonotic Diseases, full page: (LINK). Abstract, edited.]

Environmental Risk Factors and Geographic Distribution of Severe Fever with Thrombocytopenia Syndrome in Jiangsu Province, China

Dawei Zhang, Changkui Sun, Huiyan Yu, Jingxin Li, Wendong Liu, Zhifeng Li, Changjun Bao, Dapeng Liu, Nan Zhang, Fengcai Zhu, and Jianli Hu

Published Online: 17 Apr 2019 / DOI: https://doi.org/10.1089/vbz.2018.2425

 

Abstract

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging natural focus, tick-borne disease caused by a novel bunyavirus named SFTS virus (SFTSV). The main purpose of this study was to analyze the environmental risk factors and geographic distribution of SFTS natural foci in Jiangsu Province. A retrospective space–time analysis by SaTScan software was used to detect clusters at the town level. The maximum entropy modeling method was applied to construct the ecological niche model and analyze the environmental risk factors, and then to draw the predicted risk map. The performance of the model was assessed using the area under the curve (AUC) and known occurrence locations. During the years 2010–2016, a total of 140 laboratory-confirmed indigenous SFTS cases occurred in Jiangsu Province, with 66 occurrence locations. The reported number of SFTS cases increased year by year and SFTS cases occurred from April to October with a peak between May and August each year. Three clusters detected by space–time scan statistical analysis were connected together and shared the similar ecological environmental characteristic of hilly landscape. Fifteen environmental variables with different percent contribution can influence the ecological niche model in different degrees, whereas slope (suitable range: 0.1–4) and maximum temperature of warmest month (suitable range: 32.8–34.2°C) as the key environmental factors contributed 46.1% and 23.2%, respectively. The model had high accuracy on prediction with the averaged training AUC of 0.926. Within a predicted risk map, potential areas at high risk and 10 previously unidentified endemic regions were recognized. The distribution of SFTS natural foci was under the influence of multidimensional environmental factors. Slope and maximum temperature of warmest month were the key environmental risk factors. These results provide a valuable basis for the selection of prevention and control strategies, and the identification of potential risk areas.

Keywords: Bunyavirus; SFTS virus; Jiangsu; China.

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Quantitative #proteomic analysis reveals unfolded protein response involved in #SFTS virus #infection (J Virol., abstract)

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

Quantitative proteomic analysis reveals unfolded protein response involved in severe fever with thrombocytopenia syndrome virus infection

Lei-Ke Zhang, Bo Wang, Qilin Xin, Weijuan Shang, Shu Shen, Gengfu Xiao, Fei Deng, Hualin Wang, Zhihong Hu, Manli Wang

DOI: 10.1128/JVI.00308-19

 

ABSTRACT

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging, highly pathogenic, infectious disease caused by infection with a newly discovered tick-borne phlebovirus, SFTS virus (SFTSV). Limited information on the molecular mechanism of SFTSV infection and pathogenesis impedes the development of effective vaccines and drugs for SFTS prevention and treatment. In this study, an isobaric tag for relative and absolute quantification (iTRAQ)-based quantitative proteomic analysis of SFTSV-infected HEK 293 cells was performed to explore dynamic host cellular protein responses towards SFTSV infection. A total of 433 out of 5,606 host proteins involved in different biological processes were differentially regulated by SFTSV infection. The proteomic results highlighted a potential role of endoplasmic reticular stress-triggered unfolded protein response (UPR) in SFTSV infection. Further functional studies confirmed that all three major branches of the UPR, including the PRKR-like endoplasmic reticulum kinase (PERK), the activating transcription factor-6 (ATF6) and the inositol-requiring protein-1 (IRE1)-X-box-binding protein 1 (XBP1) pathways, were activated by SFTSV. However, only the former two pathways play a crucial role in SFTSV infection. Furthermore, expression of SFTSV glycoprotein (GP) alone was sufficient to stimulate the UPR, while suppression of PERK and ATF6 notably decreased GP expression. Interestingly, two other newly discovered phleboviruses, Heartland virus (HRTV) and Guertu virus (GTV), also stimulated the UPR, suggesting a common mechanism shared by these genetically related phleboviruses. This study provides a global view to our knowledge on how host cells respond to SFTSV infection and highlights that host cell UPR plays an important role in phlebovirus infection.

 

IMPORTANCE

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne bunyavirus that causes severe fever with thrombocytopenia syndrome in humans, with a mortality rate reaching up to 30% in some outbreaks. There are currently no FDA-approved vaccines or specific antivirals available against SFTSV. To comprehensively understand the molecular interactions occurring between SFTSV and the host cell, we exploit quantitative proteomic approach to investigate the dynamic host cellular responses to SFTSV infection. The results highlight multiple biological processes being regulated by SFTSV infection. Among these, we focused on exploration of the mechanism of how SFTSV infection stimulates the host cell’s unfolded protein response (UPR) and identified the UPR as a common feature shared by SFTSV-related new emerging phleboviruses. This study, for the first time to our knowledge, provides a global map for host cellular responses to SFTSV infection and highlighted potential host targets for further research.

Copyright © 2019 Zhang et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license.

Keywords: Phlebovirus; Bunyavirus; SFTS; Viral pathogenesis.

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#Viral #Infections of the #CNS in #Africa (Brain Res Bull., abstract)

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

Brain Res Bull. 2019 Jan 15. pii: S0361-9230(18)30341-1. doi: 10.1016/j.brainresbull.2018.12.019. [Epub ahead of print]

Viral Infections of the Central Nervous System in Africa.

Kakooza-Mwesige A1, Tshala-Katumbay D2, Juliano SL3.

Author information: 1 Department of Paediatrics & Child Health, Makerere University College of Health Sciences and Mulago Hospital, Kampala, Uganda; Astrid Lindgren Children’s Hospital, Neuropediatric Research Unit, Karolinska Institutet, Sweden. Electronic address: akakooza246@gmail.com. 2 Department of Neurology and School of Public Health, Oregon Health & Science University, Portland, OR, USA; Department of Neurology, University of Kinshasa, Democratic Republic of the Congo; Institut National de Recherches Biomedicales, University of Kinshasa, Democratic Republic of the Congo. Electronic address: tshalad@ohsu.edu. 3 Neuroscience, USUHS, Bethesda, MD, 20814, USA. Electronic address: sharon.juliano@usuhs.edu.

 

Abstract

Viral infections are a major cause of human central nervous system infection, and may be associated with significant mortality, and long-term sequelae. In Africa, the lack of effective therapies, limited diagnostic and human resource facilities are especially in dire need. Most viruses that affect the central nervous system are opportunistic or accidental pathogens. Some of these viruses were initially considered harmless, however they have now evolved to penetrate the nervous system efficiently and exploit neuronal cell biology thus resulting in severe illness. A number of potentially lethal neurotropic viruses have been discovered in Africa and over the course of time shown their ability to spread wider afield involving other continents leaving a devastating impact in their trail. In this review we discuss key viruses involved in central nervous system disease and of major public health concern with respect to Africa. These arise from the families of Flaviviridae, Filoviridae, Retroviridae, Bunyaviridae, Rhabdoviridae and Herpesviridae. In terms of the number of cases affected by these viruses, HIV (Retroviridae) tops the list for morbidity, mortality and long term disability, while the Rift Valley Fever virus (Bunyaviridae) is at the bottom of the list. The most deadly are the Ebola and Marburg viruses (Filoviridae). This review describes their epidemiology and key neurological manifestations as regards the central nervous system such as meningoencephalitis and Guillain-Barré syndrome. The potential pathogenic mechanisms adopted by these viruses are debated and research perspectives suggested.

Copyright © 2019. Published by Elsevier Inc.

KEYWORDS: CNS viral infections; Ebola; HIV; Herpes; Rabies; Zika

PMID: 30658129 DOI: 10.1016/j.brainresbull.2018.12.019

Keywords: Emerging Diseases; Neurology; Flavivirus; Filovirus; Rhabdovirus; Herpesvirus; HIV/AIDS; Bunyavirus; Retrovirus.

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