1
|
Baecklund TM, Donaldson ME, Hueffer K, Kyle CJ. Genetic structure of immunologically associated candidate genes suggests arctic rabies variants exert differential selection in arctic fox populations. PLoS One 2021; 16:e0258975. [PMID: 34714859 PMCID: PMC8555846 DOI: 10.1371/journal.pone.0258975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 10/10/2021] [Indexed: 11/24/2022] Open
Abstract
Patterns of local adaptation can emerge in response to the selective pressures diseases exert on host populations as reflected in increased frequencies of respective, advantageous genotypes. Elucidating patterns of local adaptation enhance our understanding of mechanisms of disease spread and the capacity for species to adapt in context of rapidly changing environments such as the Arctic. Arctic rabies is a lethal disease that largely persists in northern climates and overlaps with the distribution of its natural host, arctic fox. Arctic fox populations display little neutral genetic structure across their North American range, whereas phylogenetically unique arctic rabies variants are restricted in their geographic distributions. It remains unknown if arctic rabies variants impose differential selection upon host populations, nor what role different rabies variants play in the maintenance and spread of this disease. Using a targeted, genotyping-by-sequencing assay, we assessed correlations of arctic fox immunogenetic variation with arctic rabies variants to gain further insight into the epidemiology of this disease. Corroborating past research, we found no neutral genetic structure between sampled regions, but did find moderate immunogenetic structuring between foxes predominated by different arctic rabies variants. FST outliers associated with host immunogenetic structure included SNPs within interleukin and Toll-like receptor coding regions (IL12B, IL5, TLR3 and NFKB1); genes known to mediate host responses to rabies. While these data do not necessarily reflect causation, nor a direct link to arctic rabies, the contrasting genetic structure of immunologically associated candidate genes with neutral loci is suggestive of differential selection and patterns of local adaptation in this system. These data are somewhat unexpected given the long-lived nature and dispersal capacities of arctic fox; traits expected to undermine local adaptation. Overall, these data contribute to our understanding of the co-evolutionary relationships between arctic rabies and their primary host and provide data relevant to the management of this disease.
Collapse
Affiliation(s)
- Tristan M. Baecklund
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON, Canada
- * E-mail:
| | - Michael E. Donaldson
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON, Canada
| | - Karsten Hueffer
- Department of Veterinary Medicine, University of Alaska Fairbanks, Fairbanks, AK, United States of America
| | - Christopher J. Kyle
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON, Canada
- Forensic Science Department, Trent University, Peterborough, ON, Canada
- Natural Resources DNA Profiling & Forensic Centre, Trent University, Peterborough, ON, Canada
| |
Collapse
|
2
|
Baecklund TM, Morrison J, Donaldson ME, Hueffer K, Kyle CJ. The role of a mechanistic host in maintaining arctic rabies variant distributions: Assessment of functional genetic diversity in Alaskan red fox (Vulpes vulpes). PLoS One 2021; 16:e0249176. [PMID: 33831031 PMCID: PMC8031376 DOI: 10.1371/journal.pone.0249176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 03/12/2021] [Indexed: 11/18/2022] Open
Abstract
Populations are exposed to different types and strains of pathogens across heterogeneous landscapes, where local interactions between host and pathogen may present reciprocal selective forces leading to correlated patterns of spatial genetic structure. Understanding these coevolutionary patterns provides insight into mechanisms of disease spread and maintenance. Arctic rabies (AR) is a lethal disease with viral variants that occupy distinct geographic distributions across North America and Europe. Red fox (Vulpes vulpes) are a highly susceptible AR host, whose range overlaps both geographically distinct AR strains and regions where AR is absent. It is unclear if genetic structure exists among red fox populations relative to the presence/absence of AR or the spatial distribution of AR variants. Acquiring these data may enhance our understanding of the role of red fox in AR maintenance/spread and inform disease control strategies. Using a genotyping-by-sequencing assay targeting 116 genomic regions of immunogenetic relevance, we screened for sequence variation among red fox populations from Alaska and an outgroup from Ontario, including areas with different AR variants, and regions where the disease was absent. Presumed neutral SNP data from the assay found negligible levels of neutral genetic structure among Alaskan populations. The immunogenetically-associated data identified 30 outlier SNPs supporting weak to moderate genetic structure between regions with and without AR in Alaska. The outliers included SNPs with the potential to cause missense mutations within several toll-like receptor genes that have been associated with AR outcome. In contrast, there was a lack of genetic structure between regions with different AR variants. Combined, we interpret these data to suggest red fox populations respond differently to the presence of AR, but not AR variants. This research increases our understanding of AR dynamics in the Arctic, where host/disease patterns are undergoing flux in a rapidly changing Arctic landscape, including the continued northward expansion of red fox into regions previously predominated by the arctic fox (Vulpes lagopus).
Collapse
Affiliation(s)
- Tristan M. Baecklund
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, Ontario, Canada
- * E-mail:
| | - Jaycee Morrison
- Forensic Science Undergraduate Program, Trent University, Peterborough, Ontario, Canada
| | - Michael E. Donaldson
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, Ontario, Canada
| | - Karsten Hueffer
- Department of Veterinary Medicine, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America
| | - Christopher J. Kyle
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, Ontario, Canada
- Forensic Science Department, Trent University, Peterborough, Ontario, Canada
- Natural Resources DNA Profiling & Forensic Centre, Trent University, Peterborough, Ontario, Canada
| |
Collapse
|
3
|
Guito JC, Prescott JB, Arnold CE, Amman BR, Schuh AJ, Spengler JR, Sealy TK, Harmon JR, Coleman-McCray JD, Kulcsar KA, Nagle ER, Kumar R, Palacios GF, Sanchez-Lockhart M, Towner JS. Asymptomatic Infection of Marburg Virus Reservoir Bats Is Explained by a Strategy of Immunoprotective Disease Tolerance. Curr Biol 2020; 31:257-270.e5. [PMID: 33157026 DOI: 10.1016/j.cub.2020.10.015] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 07/28/2020] [Accepted: 10/07/2020] [Indexed: 12/25/2022]
Abstract
Marburg virus (MARV) is among the most virulent pathogens of primates, including humans. Contributors to severe MARV disease include immune response suppression and inflammatory gene dysregulation ("cytokine storm"), leading to systemic damage and often death. Conversely, MARV causes little to no clinical disease in its reservoir host, the Egyptian rousette bat (ERB). Previous genomic and in vitro data suggest that a tolerant ERB immune response may underlie MARV avirulence, but no significant examination of this response in vivo yet exists. Here, using colony-bred ERBs inoculated with a bat isolate of MARV, we use species-specific antibodies and an immune gene probe array (NanoString) to temporally characterize the transcriptional host response at sites of MARV replication relevant to primate pathogenesis and immunity, including CD14+ monocytes/macrophages, critical immune response mediators, primary MARV targets, and skin at the inoculation site, where highest viral loads and initial engagement of antiviral defenses are expected. Our analysis shows that ERBs upregulate canonical antiviral genes typical of mammalian systems, such as ISG15, IFIT1, and OAS3, yet demonstrate a remarkable lack of significant induction of proinflammatory genes classically implicated in primate filoviral pathogenesis, including CCL8, FAS, and IL6. Together, these findings offer the first in vivo functional evidence for disease tolerance as an immunological mechanism by which the bat reservoir asymptomatically hosts MARV. More broadly, these data highlight factors determining disparate outcomes between reservoir and spillover hosts and defensive strategies likely utilized by bat hosts of other emerging pathogens, knowledge that may guide development of effective antiviral therapies.
Collapse
Affiliation(s)
- Jonathan C Guito
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Joseph B Prescott
- Center for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany
| | - Catherine E Arnold
- Diagnostic Systems Division, U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, MD 21702, USA
| | - Brian R Amman
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Amy J Schuh
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Jessica R Spengler
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Tara K Sealy
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Jessica R Harmon
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - JoAnn D Coleman-McCray
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Kirsten A Kulcsar
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Elyse R Nagle
- Center for Genome Sciences, USAMRIID, Fort Detrick, MD 21702, USA
| | - Raina Kumar
- Center for Genome Sciences, USAMRIID, Fort Detrick, MD 21702, USA
| | | | - Mariano Sanchez-Lockhart
- Center for Genome Sciences, USAMRIID, Fort Detrick, MD 21702, USA; Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Jonathan S Towner
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA; Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA.
| |
Collapse
|
4
|
Rabies virus infection in mice up-regulates B7-H1 via epigenetic modifications. Virusdisease 2020; 31:388-394. [DOI: 10.1007/s13337-020-00588-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 04/24/2020] [Indexed: 10/24/2022] Open
|
5
|
Abdulazeez M, Kia GSN, Abarshi MM, Muhammad A, Ojedapo CE, Atawodi JC, Dantong D, Kwaga JKP. Induction of Rabies Virus Infection in Mice Brain may Up and Down Regulate Type II Interferon gamma via epigenetic modifications. Metab Brain Dis 2020; 35:819-827. [PMID: 32172520 PMCID: PMC7223763 DOI: 10.1007/s11011-020-00553-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 02/17/2020] [Indexed: 12/17/2022]
Abstract
As feared and deadly human diseases globally, Rabies virus contrived mechanisms to escape early immune recognition via suppression of the interferon response. This study, preliminarily investigated whether Rabies virus employs epigenetic mechanism for the suppression of the interferon using the Challenge virus standard (CVS) strain and Nigerian street Rabies virus (SRV) strain. Mice were challenged with Rabies virus (RABV) infection, and presence of RABV antigen was assessed by direct fluorescent antibody test (DFAT). A real time quantitative Polymerase chain reaction (qRT-PCR) was used to measure the expression of type II interferon gamma (IFNG) and methylation specific quantitative PCR for methylation analysis of 1FNG promoter region. Accordingly, DNA methyltransferase (DNMT) and histone acetyltransferase (HAT) enzymes activities were determined. RABV antigen was detected in all infected samples. A statistically significant increase (p < 0.05) in mRNA level of IFNG was observed at the onset of the disease and a decrease as the disease progressed. An increase in methylation in the test groups from the control group was observed, with a fluctuation in methylation as the disease progressed. DNMT and HAT activities also agree with methylation as there was an observed increase activity in test group compared with control group. Similar fluctuation pattern was observed in both CVS and SRV groups as the disease progressed with HAT, being the most active proportionally. This study suggests that epigenetic modification via DNA methylation and histone acetylation may have played a role in the expression of type II interferon gamma in Rabies virus infection. Graphical abstract.
Collapse
Affiliation(s)
- Maryam Abdulazeez
- Department of Biochemistry, Faculty of Life Sciences, Ahmadu Bello University, ZariaKaduna State, Nigeria
- Africa Centre of Excellence for Neglected Tropical Diseases and Forensic Biotechnology, Ahmadu Bello University, Zaria, Nigeria
| | - Grace S. N. Kia
- Africa Centre of Excellence for Neglected Tropical Diseases and Forensic Biotechnology, Ahmadu Bello University, Zaria, Nigeria
- Department of Public health and Preventive Medicine, Ahmadu Bello University, Zaria, Nigeria
| | - Musa M. Abarshi
- Department of Biochemistry, Faculty of Life Sciences, Ahmadu Bello University, ZariaKaduna State, Nigeria
- Africa Centre of Excellence for Neglected Tropical Diseases and Forensic Biotechnology, Ahmadu Bello University, Zaria, Nigeria
| | - Aliyu Muhammad
- Department of Biochemistry, Faculty of Life Sciences, Ahmadu Bello University, ZariaKaduna State, Nigeria
- Africa Centre of Excellence for Neglected Tropical Diseases and Forensic Biotechnology, Ahmadu Bello University, Zaria, Nigeria
| | - Comfort E. Ojedapo
- Department of Biochemistry, Faculty of Life Sciences, Ahmadu Bello University, ZariaKaduna State, Nigeria
- Africa Centre of Excellence for Neglected Tropical Diseases and Forensic Biotechnology, Ahmadu Bello University, Zaria, Nigeria
| | - Joy Cecilia Atawodi
- Department of Public health and Preventive Medicine, Ahmadu Bello University, Zaria, Nigeria
| | - David Dantong
- Department of Microbiology, Faculty of Veterinary Medicine, University of Abuja, Abuja, Nigeria
| | - Jacob K. P. Kwaga
- Africa Centre of Excellence for Neglected Tropical Diseases and Forensic Biotechnology, Ahmadu Bello University, Zaria, Nigeria
- Department of Public health and Preventive Medicine, Ahmadu Bello University, Zaria, Nigeria
| |
Collapse
|
6
|
Golahdooz M, Eybpoosh S, Bashar R, Taherizadeh M, Pourhossein B, Shirzadi M, Amiri B, Fazeli M. Comparison of Immune Responses following Intradermal and Intramuscular Rabies Vaccination Methods. JOURNAL OF MEDICAL MICROBIOLOGY AND INFECTIOUS DISEASES 2018. [DOI: 10.29252/jommid.6.4.77] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
|
7
|
Craigie M, Cicalese S, Sariyer IK. Neuroimmune Regulation of JC Virus by Intracellular and Extracellular Agnoprotein. J Neuroimmune Pharmacol 2017; 13:126-142. [PMID: 29159704 DOI: 10.1007/s11481-017-9770-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 11/10/2017] [Indexed: 12/12/2022]
Abstract
JC virus (JCV) is a human polyomavirus and the etiologic agent of the demyelinating disease progressive multifocal leukoencephalopathy (PML). PML is observed in patients with underlying immunocompromising conditions, suggesting that neuro-immune interactions between peripheral immune cells and neuro-glia play an important role in controlling viral reactivation in the brain. There is little known about the immunobiology of JCV reactivation in glial cells and the role of immune, glial, and viral players in this regulation. We have previously showed that agnoprotein, a small JCV regulatory protein, is released from infected cells and internalized by neighboring bystander cells. Here we have investigated the possible role of extracellular and intracellular agnoprotein in the neuroimmune response to JC virus. Our findings suggest that glial cells exposed to agnoprotein secrete significantly less GM-CSF, which is mediated by agnoprotein induced suppression of GM-CSF transcription. Likewise, monocytes treated with agnoprotein showed altered differentiation and maturation. In addition, monocytes and microglial cells exposed to agnoprotein showed a significant reduction in their phagocytic activities. Moreover, when an in vitro blood-brain barrier model was used, agnoprotein treatment resulted in decreased monocyte migration through the endothelial cell layer in response to activated astrocytes. All together, these results have revealed a novel immunomodulatory function of agnoprotein during JCV infection within theCNS and open a new avenue of research to better understand the mechanisms associated with JCV reactivation in patients who are at risk of developing PML.
Collapse
Affiliation(s)
- Michael Craigie
- Department of Neuroscience and Center for Neurovirology, Temple University Lewis Katz School of Medicine, 3500 N. Broad Street, Philadelphia, PA, 19140, USA
| | - Stephanie Cicalese
- Department of Neuroscience and Center for Neurovirology, Temple University Lewis Katz School of Medicine, 3500 N. Broad Street, Philadelphia, PA, 19140, USA
| | - Ilker Kudret Sariyer
- Department of Neuroscience and Center for Neurovirology, Temple University Lewis Katz School of Medicine, 3500 N. Broad Street, Philadelphia, PA, 19140, USA.
| |
Collapse
|
8
|
Azimzadeh Jamalkandi S, Mozhgani SH, Gholami Pourbadie H, Mirzaie M, Noorbakhsh F, Vaziri B, Gholami A, Ansari-Pour N, Jafari M. Systems Biomedicine of Rabies Delineates the Affected Signaling Pathways. Front Microbiol 2016; 7:1688. [PMID: 27872612 PMCID: PMC5098112 DOI: 10.3389/fmicb.2016.01688] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 10/07/2016] [Indexed: 12/16/2022] Open
Abstract
The prototypical neurotropic virus, rabies, is a member of the Rhabdoviridae family that causes lethal encephalomyelitis. Although there have been a plethora of studies investigating the etiological mechanism of the rabies virus and many precautionary methods have been implemented to avert the disease outbreak over the last century, the disease has surprisingly no definite remedy at its late stages. The psychological symptoms and the underlying etiology, as well as the rare survival rate from rabies encephalitis, has still remained a mystery. We, therefore, undertook a systems biomedicine approach to identify the network of gene products implicated in rabies. This was done by meta-analyzing whole-transcriptome microarray datasets of the CNS infected by strain CVS-11, and integrating them with interactome data using computational and statistical methods. We first determined the differentially expressed genes (DEGs) in each study and horizontally integrated the results at the mRNA and microRNA levels separately. A total of 61 seed genes involved in signal propagation system were obtained by means of unifying mRNA and microRNA detected integrated DEGs. We then reconstructed a refined protein–protein interaction network (PPIN) of infected cells to elucidate the rabies-implicated signal transduction network (RISN). To validate our findings, we confirmed differential expression of randomly selected genes in the network using Real-time PCR. In conclusion, the identification of seed genes and their network neighborhood within the refined PPIN can be useful for demonstrating signaling pathways including interferon circumvent, toward proliferation and survival, and neuropathological clue, explaining the intricate underlying molecular neuropathology of rabies infection and thus rendered a molecular framework for predicting potential drug targets.
Collapse
Affiliation(s)
| | - Sayed-Hamidreza Mozhgani
- Department of Virology, School of Public Health, Tehran University of Medical Sciences Tehran, Iran
| | | | - Mehdi Mirzaie
- Department of Applied Mathematics, Faculty of Mathematical Sciences, Tarbiat Modares University Tehran, Iran
| | - Farshid Noorbakhsh
- Department of Immunology, School of Medicine, Tehran University of Medical Sciences Tehran, Iran
| | - Behrouz Vaziri
- Protein Chemistry and Proteomics Unit, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran Tehran, Iran
| | - Alireza Gholami
- WHO Collaborating Center for Reference and Research on Rabies, Pasteur Institute of Iran Tehran, Iran
| | - Naser Ansari-Pour
- Faculty of New Sciences and Technology, University of TehranTehran, Iran; Department of Genetics, Evolution and Environment, UCL Genetics Institute, University College LondonLondon, UK
| | - Mohieddin Jafari
- Drug Design and Bioinformatics Unit, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran Tehran, Iran
| |
Collapse
|
9
|
Scott TP, Nel LH. Subversion of the Immune Response by Rabies Virus. Viruses 2016; 8:v8080231. [PMID: 27548204 PMCID: PMC4997593 DOI: 10.3390/v8080231] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 08/11/2016] [Accepted: 08/12/2016] [Indexed: 12/24/2022] Open
Abstract
Rabies has affected mankind for several centuries and is one of the oldest known zoonoses. It is peculiar how little is known regarding the means by which rabies virus (RABV) evades the immune response and kills its host. This review investigates the complex interplay between RABV and the immune system, including the various means by which RABV evades, or advantageously utilizes, the host immune response in order to ensure successful replication and spread to another host. Different factors that influence immune responses—including age, sex, cerebral lateralization and temperature—are discussed, with specific reference to RABV and the effects on host morbidity and mortality. We also investigate the role of apoptosis and discuss whether it is a detrimental or beneficial mechanism of the host’s response to infection. The various RABV proteins and their roles in immune evasion are examined in depth with reference to important domains and the downstream effects of these interactions. Lastly, an overview of the means by which RABV evades important immune responses is provided. The research discussed in this review will be important in determining the roles of the immune response during RABV infections as well as to highlight important therapeutic target regions and potential strategies for rabies treatment.
Collapse
Affiliation(s)
- Terence P Scott
- Department of Microbiology and Plant Pathology, University of Pretoria, Pretoria 0002, South Africa.
| | - Louis H Nel
- Department of Microbiology and Plant Pathology, University of Pretoria, Pretoria 0002, South Africa.
| |
Collapse
|
10
|
Rupprecht CE, Nagarajan T, Ertl H. Current Status and Development of Vaccines and Other Biologics for Human Rabies Prevention. Expert Rev Vaccines 2016; 15:731-49. [PMID: 26796599 DOI: 10.1586/14760584.2016.1140040] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Rabies is a neglected viral zoonosis with the highest case fatality of any infectious disease. Pasteur's historical accomplishments during the late 19(th) century began the process of human vaccine development, continuing to evolve into the 21(st) century. Over the past 35 years, great improvements occurred in the production of potent tissue culture vaccines and the gradual removal from the market of unsafe nerve tissue products. Timely and appropriate administration of modern biologics virtually assures survivorship, even after severe exposures. Nevertheless, in the developing world, if not provided for free nationally, the cost of a single course of human prophylaxis exceeds the average monthly wage of the common worker. Beyond traditional approaches, recombinant, sub-unit and other novel methods are underway to improve the availability of safe, effective and more affordable rabies biologics.
Collapse
|
11
|
Lack of Spatial Immunogenetic Structure among Wolverine (Gulo gulo) Populations Suggestive of Broad Scale Balancing Selection. PLoS One 2015; 10:e0140170. [PMID: 26448462 PMCID: PMC4598017 DOI: 10.1371/journal.pone.0140170] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 09/22/2015] [Indexed: 11/19/2022] Open
Abstract
Elucidating the adaptive genetic potential of wildlife populations to environmental selective pressures is fundamental for species conservation. Genes of the major histocompatibility complex (MHC) are highly polymorphic, and play a key role in the adaptive immune response against pathogens. MHC polymorphism has been linked to balancing selection or heterogeneous selection promoting local adaptation. However, spatial patterns of MHC polymorphism are also influenced by gene flow and drift. Wolverines are highly vagile, inhabiting varied ecoregions that include boreal forest, taiga, tundra, and high alpine ecosystems. Here, we investigated the immunogenetic variation of wolverines in Canada as a surrogate for identifying local adaptation by contrasting the genetic structure at MHC relative to the structure at 11 neutral microsatellites to account for gene flow and drift. Evidence of historical positive selection was detected at MHC using maximum likelihood codon-based methods. Bayesian and multivariate cluster analyses revealed weaker population genetic differentiation at MHC relative to the increasing microsatellite genetic structure towards the eastern wolverine distribution. Mantel correlations of MHC against geographical distances showed no pattern of isolation by distance (IBD: r = -0.03, p = 0.9), whereas for microsatellites we found a relatively strong and significant IBD (r = 0.54, p = 0.01). Moreover, we found a significant correlation between microsatellite allelic richness and the mean number of MHC alleles, but we did not observe low MHC diversity in small populations. Overall these results suggest that MHC polymorphism has been influenced primarily by balancing selection and to a lesser extent by neutral processes such as genetic drift, with no clear evidence for local adaptation. This study contributes to our understanding of how vulnerable populations of wolverines may respond to selective pressures across their range.
Collapse
|
12
|
Yang DK, Kim HH, Choi SS, Kim JT, Jeong WH, Song JY. Oral immunization of mice with recombinant rabies vaccine strain (ERAG3G) induces complete protection. Clin Exp Vaccine Res 2015; 4:107-13. [PMID: 25648184 PMCID: PMC4313102 DOI: 10.7774/cevr.2015.4.1.107] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 12/28/2014] [Accepted: 12/31/2014] [Indexed: 11/15/2022] Open
Abstract
PURPOSE New rabies vaccine bait for both pets and raccoon dogs residing in Korea is needed to eradicate rabies infection among animals. In this study, we constructed a recombinant rabies virus (RABV), the ERAG3G strain, using a reverse genetics system. Then we investigated the efficacy of this strain in mice after oral administration and the safety of this strain in cats after intramuscular administration. MATERIALS AND METHODS The ERAG3G strain was rescued in BHK/T7-9 cells using the full-length genome mutated at the amino acid position 333 of the glycoprotein gene of RABV and helper plasmids. Four-week-old mice underwent one or two oral administrations of the ERAG3G strain and were challenged with the highly virulent RABV strain CVSN2c 14 days after the second administration. Clinical symptoms were observed and body weights were measured every day after the challenge. RESULTS All mice showed complete protection against virulent RABV. In addition, cats intramuscularly inoculated with the ERAG3G strain showed high antibody titers ranging from 2.62 to 23.9 IU/mL at 28-day postinoculation. CONCLUSION The oral immunization of the ERAG3G strain plays an important role in conferring complete protection in mice, and intramuscular inoculation of the ERAG3G strain induces the formation of anti-rabies neutralizing antibody in cats.
Collapse
Affiliation(s)
- Dong-Kun Yang
- Viral Disease Division, Animal and Plant Quarantine Agency, MAFRA, Anyang, Korea
| | - Ha-Hyun Kim
- Viral Disease Division, Animal and Plant Quarantine Agency, MAFRA, Anyang, Korea
| | - Sung-Suk Choi
- Viral Disease Division, Animal and Plant Quarantine Agency, MAFRA, Anyang, Korea
| | - Jong-Taek Kim
- College of Veterinary Medicine, Kangwon National University, Chuncheon, Korea
| | - Woong-Ho Jeong
- Gangwon-do Veterinary Service Laboratory, Chuncheon, Korea
| | - Jae-Young Song
- Viral Disease Division, Animal and Plant Quarantine Agency, MAFRA, Anyang, Korea
| |
Collapse
|