Enterovirus infections

2020 ◽  
pp. 787-797
Author(s):  
Philip Minor ◽  
Ulrich Desselberger
Keyword(s):  
Spinal Cord ◽  
Rna Viruses ◽  
Oral Route ◽  
Lymphoid Cells ◽  
Human Enterovirus ◽  
Temperate Climate ◽  
Sequence Comparisons ◽  
Tropical Regions ◽  
Mucosal Surfaces ◽  
Coxsackie B Viruses

Enteroviruses are single-stranded, positive-sense RNA viruses comprising poliomyelitis viruses (3 types), coxsackie A viruses (23 types), coxsackie B viruses (6 types), and echoviruses (33 types). They have recently been reclassified into four human enterovirus species (A–D) on the basis of sequence comparisons. Transmission is by the faeco-oral route, with marked seasonal peaks of infection in areas of temperate climate, but infections occurring all year round in tropical regions. Following transmission, enteroviruses undergo a first round of replication in cells of the mucosal surfaces of the gastrointestinal tract and in gut-associated lymphoid cells, followed by viraemia, which leads to infection of distant organs (brain, spinal cord, meninges, myocardium, muscle, skin, and so on), where lesions might be produced. Shedding of virus occurs from throat and faeces for many weeks.

Enterovirus infections

2010 ◽  
pp. 527-536
Author(s):  
Philip Minor ◽  
Ulrich Desselberger
Keyword(s):  
Rna Viruses ◽  
Oral Route ◽  
Human Enterovirus ◽  
Temperate Climate ◽  
Sequence Comparisons ◽  
Tropical Regions ◽  
Positive Sense ◽  
Coxsackie B Viruses ◽  
Coxsackie B

Enteroviruses are single-stranded, positive sense RNA viruses comprising poliomyelitis viruses (3 types), Coxsackie A viruses (23 types), Coxsackie B viruses (6 types), and echoviruses (33 types). They have recently been reclassified into 4 human enterovirus species (A–D) on the basis of sequence comparisons. Transmission is by the faeco-oral route, with marked seasonal peaks of infection in areas of temperate climate, but infections occurring all year round in tropical regions....

scholarly journals Gata3 drives development of RORγt+ group 3 innate lymphoid cells

2014 ◽  
Vol 211 (2) ◽  
pp. 199-208 ◽  
Author(s):  
Nicolas Serafini ◽  
Roel G.J. Klein Wolterink ◽  
Naoko Satoh-Takayama ◽  
Wei Xu ◽  
Christian A.J. Vosshenrich ◽  
...  
Keyword(s):  
T Cell ◽  
Fetal Liver ◽  
Innate Lymphoid Cells ◽  
Lymphoid Cells ◽  
T Cell Subsets ◽  
Mucosal Barrier ◽  
Hematopoietic Stem ◽  
Mucosal Surfaces ◽  
Gata3 Expression ◽  
Group 3

Group 3 innate lymphoid cells (ILC3) include IL-22–producing NKp46+ cells and IL-17A/IL-22–producing CD4+ lymphoid tissue inducerlike cells that express RORγt and are implicated in protective immunity at mucosal surfaces. Whereas the transcription factor Gata3 is essential for T cell and ILC2 development from hematopoietic stem cells (HSCs) and for IL-5 and IL-13 production by T cells and ILC2, the role for Gata3 in the generation or function of other ILC subsets is not known. We found that abundant GATA-3 protein is expressed in mucosa-associated ILC3 subsets with levels intermediate between mature B cells and ILC2. Chimeric mice generated with Gata3-deficient fetal liver hematopoietic precursors lack all intestinal RORγt+ ILC3 subsets, and these mice show defective production of IL-22 early after infection with the intestinal pathogen Citrobacter rodentium, leading to impaired survival. Further analyses demonstrated that ILC3 development requires cell-intrinsic Gata3 expression in fetal liver hematopoietic precursors. Our results demonstrate that Gata3 plays a generalized role in ILC lineage determination and is critical for the development of gut RORγt+ ILC3 subsets that maintain mucosal barrier homeostasis. These results further extend the paradigm of Gata3-dependent regulation of diversified innate ILC and adaptive T cell subsets.

scholarly journals RNA Recombination Plays a Major Role in Genomic Change during Circulation of Coxsackie B Viruses

2004 ◽  
Vol 78 (6) ◽  
pp. 2948-2955 ◽  
Author(s):  
M. Steven Oberste ◽  
Silvia Peñaranda ◽  
Mark A. Pallansch
Keyword(s):  
Phylogenetic Trees ◽  
Clinical Isolates ◽  
Human Enterovirus ◽  
Rna Recombination ◽  
Genomic Change ◽  
Genome Region ◽  
Nontranslated Region ◽  
Frequent Event ◽  
Coxsackie B Viruses ◽  
Coxsackie B

ABSTRACT RNA recombination has been shown to occur during circulation of enteroviruses, but most studies have focused on poliovirus. To examine the role of recombination in the evolution of the coxsackie B viruses (CVB), we determined the partial sequences of four genomic intervals for multiple clinical isolates of each of the six CVB serotypes isolated from 1970 to 1996. The regions sequenced were the 5′-nontranslated region (5′-NTR) (350 nucleotides [nt]), capsid (VP4-VP2, 416 nt, and VP1, ∼320 nt), and polymerase (3D, 491 nt). Phylogenetic trees were constructed for each genome region, using the clinical isolate sequences and those of the prototype strains of all 65 enterovirus serotypes. The partial VP1 sequences of each CVB serotype were monophyletic with respect to serotype, as were the VP4-VP2 sequences, in agreement with previously published studies. In some cases, however, incongruent tree topologies suggested that intraserotypic recombination had occurred between the sequenced portions of VP2 and VP1. Outside the capsid region, however, isolates of the same serotype were not monophyletic, indicating that recombination had occurred between the 5′-NTR and capsid, the capsid and 3D, or both. Almost all clinical isolates were recombinant relative to the prototype strain of the same serotype. All of the recombination partners appear to be members of human enterovirus species B. These results suggest that recombination is a frequent event during enterovirus evolution but that there are genetic restrictions that may influence recombinational compatibility.

scholarly journals Comparative Gene Genealogies Indicate that Two Clonal Lineages of Cryptococcus gattii in British Columbia Resemble Strains from Other Geographical Areas

2005 ◽  
Vol 4 (10) ◽  
pp. 1629-1638 ◽  
Author(s):  
Sarah E. Kidd ◽  
Hong Guo ◽  
Karen H. Bartlett ◽  
Jianping Xu ◽  
James W. Kronstad
Keyword(s):  
British Columbia ◽  
Population Structure ◽  
Nucleotide Sequence ◽  
Global Scale ◽  
Cryptococcus Gattii ◽  
Temperate Climate ◽  
Molecular Type ◽  
Sequence Comparisons ◽  
The World ◽  
Clonal Population Structure

ABSTRACT Cryptococcus gattii has recently emerged as a pathogen of humans and animals in the temperate climate of Vancouver Island, British Columbia (B.C.). The majority (∼95%) of the isolates from the island belong to the VGII molecular type, and the remainder belong to the VGI molecular type. The goals of this study were to compare patterns of molecular variation among C. gattii isolates from B.C. with those from different areas of the world and to investigate the population structure using a comparative gene genealogy approach. Our results indicate that the C. gattii population in B.C. comprises at least two divergent lineages, corresponding to previously identified VGI and VGII molecular types. The genealogical analysis of strains suggested a predominantly clonal population structure among B.C. isolates, while there was evidence for sexual recombination between different molecular types on a global scale. We found no geographic pattern of strain relationships, and nucleotide sequence comparisons revealed that genotypes among isolates from B.C. were also present among isolates from other areas of the world, indicating extensive strain dispersal. The nucleotide sequence diversity among isolates from B.C. was similar to that among isolates from other areas of the world.

scholarly journals Type 3 innate lymphoid cells maintain intestinal epithelial stem cells after tissue damage

2015 ◽  
Vol 212 (11) ◽  
pp. 1783-1791 ◽  
Author(s):  
Patricia Aparicio-Domingo ◽  
Monica Romera-Hernandez ◽  
Julien J. Karrich ◽  
Ferry Cornelissen ◽  
Natalie Papazian ◽  
...  
Keyword(s):  
Stem Cells ◽  
Tissue Damage ◽  
Innate Lymphoid Cells ◽  
Lymphoid Cells ◽  
Intestinal Damage ◽  
Intestinal Epithelial ◽  
Epithelial Stem Cells ◽  
Intestinal Tissue ◽  
Mucosal Surfaces ◽  
Type 3

Disruption of the intestinal epithelial barrier allows bacterial translocation and predisposes to destructive inflammation. To ensure proper barrier composition, crypt-residing stem cells continuously proliferate and replenish all intestinal epithelial cells within days. As a consequence of this high mitotic activity, mucosal surfaces are frequently targeted by anticancer therapies, leading to dose-limiting side effects. The cellular mechanisms that control tissue protection and mucosal healing in response to intestinal damage remain poorly understood. Type 3 innate lymphoid cells (ILC3s) are regulators of homeostasis and tissue responses to infection at mucosal surfaces. We now demonstrate that ILC3s are required for epithelial activation and proliferation in response to small intestinal tissue damage induced by the chemotherapeutic agent methotrexate. Multiple subsets of ILC3s are activated after intestinal tissue damage, and in the absence of ILC3s, epithelial activation is lost, correlating with increased pathology and severe damage to the intestinal crypts. Using ILC3-deficient Lgr5 reporter mice, we show that maintenance of intestinal stem cells after damage is severely impaired in the absence of ILC3s or the ILC3 signature cytokine IL-22. These data unveil a novel function of ILC3s in limiting tissue damage by preserving tissue-specific stem cells.

scholarly journals T-bet fate mapping identifies a novel ILC1-ILC2 subset in vivo

2020 ◽  
Author(s):  
J-H Schroeder ◽  
N Garrido-Mesa ◽  
T Zabinski ◽  
AL Gallagher ◽  
L Campbell ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Immune Responses ◽  
Critical Role ◽  
Innate Lymphoid Cells ◽  
Lymphoid Cells ◽  
Fate Mapping ◽  
Functional Roles ◽  
Mucosal Surfaces ◽  
Group 2

ABSTRACTInnate lymphoid cells (ILC) play a critical role in regulating immune responses at mucosal surfaces. Various subsets exist resembling T cell lineages defined by the expression of specific transcription factors. Thus, T-bet is expressed in ILC1 and Th1 cells. In order to further understand the functional roles of T-bet in ILC, we generated a fate-mapping mouse model that permanently marks cells and their progeny that are expressing, or have ever expressed T-bet. Here we have identified and characterised a novel ILC with characteristics of ILC1 and ILC2 that are “fate-mapped” for T-bet expression and arise early in neonatal life prior to establishment of a mature microbiome. These ILC1-ILC2 cells are critically dependent on T-bet and are able to express type 1 and type 2 cytokines at steady state, but not in the context of inflammation. These findings refine our understanding of ILC lineage regulation and stability and have important implications for the understanding of ILC biology at mucosal surfaces.SUMMARYInnate lymphoid cells (ILC) play a critical role in regulating immune responses at mucosal surfaces. Three distinct ILC groups have been described according to expression of subset defining transcription factors and other markers. In this study we characterize a novel ILC subset with characteristics of group 1 and group 2 ILC in vivo.

Antihypernociceptive and antioxidant effects of Petersianthus macrocarpus stem bark extracts in rats with complete Freund’s adjuvant-induced persistent inflammatory pain

2017 ◽  
Vol 14 (2) ◽  
Author(s):  
Francis Desire Tatsinkou Bomba ◽  
Bibiane Aimée Wandji ◽  
Christian Kuete Fofié ◽  
Albert Kamanyi ◽  
Télesphore Benoit Nguelefack
Keyword(s):  
Spinal Cord ◽  
Inflammatory Pain ◽  
Folk Medicine ◽  
Antioxidant Properties ◽  
Stem Bark ◽  
Oral Route ◽  
Mechanical Hyperalgesia ◽  
Intraplantar Injection ◽  
Field Device ◽  
The Brain

AbstractBackground(P. Beauv.) Liben (Lecythidaceae) is a plant used in Cameroonian folk medicine to cure ailments such as inflammation and pain. Previous work showed that aqueous (AEPM) and methanol (MEPM) extracts from the stem bark ofMethodsInflammatory pain was induced by intraplantar injection of CFA into the left hind paw of Wistar rats. AEPM and MEPM were administered either acutely or chronically by the oral route at the doses of 100 and 200 mg/kg/day. The mechanical hyperalgesia was tested using an analgesimeter, while the locomotion activity at the end of experiment was evaluated with an open-field device. Nitric oxide (NO), malondialdehyde (MDA) and superoxide dismutase (SOD) contents were assayed in the brain and spinal cord of rats subjected to 14 days chronic treatment.ResultsAEPM and MEPM at both doses significantly (p<0.001) inhibited the acute and chronic mechanical hyperalgesia induced by CFA. Although not significant, both extracts increased the mobility of CFA-injected animals. AEPM significantly (p<0.01) reduced the level of nitrate at 100 mg/kg, MDA at 200 mg/kg and significantly (p<0.05) increased the SOD in the spinal cord. MEPM significantly increased the SOD content and reduced the MDA concentration in the brain but had no effect on the nitrate.ConclusionsAEPM and MEPM exhibit acute and chronic antihyperalgesic activities. In addition, both extracts possess antioxidant properties that might strengthen their chronic antihyperalgesic effects.

scholarly journals Oral-resident natural Th17 cells and γδ T cells control opportunistic Candida albicans infections

2014 ◽  
Vol 211 (10) ◽  
pp. 2075-2084 ◽  
Author(s):  
Heather R. Conti ◽  
Alanna C. Peterson ◽  
Lucas Brane ◽  
Anna R. Huppler ◽  
Nydiaris Hernández-Santos ◽  
...  
Keyword(s):  
T Cells ◽  
Candida Albicans ◽  
Γδ T Cells ◽  
Clonal Diversity ◽  
Lymphoid Cells ◽  
Innate Response ◽  
Tcr Signaling ◽  
Reporter Mice ◽  
Mucosal Surfaces ◽  
Oral Pathogens

Oropharyngeal candidiasis (OPC) is an opportunistic fungal infection caused by Candida albicans. OPC is frequent in HIV/AIDS, implicating adaptive immunity. Mice are naive to Candida, yet IL-17 is induced within 24 h of infection, and susceptibility is strongly dependent on IL-17R signaling. We sought to identify the source of IL-17 during the early innate response to candidiasis. We show that innate responses to Candida require an intact TCR, as SCID, IL-7Rα−/−, and Rag1−/− mice were susceptible to OPC, and blockade of TCR signaling by cyclosporine induced susceptibility. Using fate-tracking IL-17 reporter mice, we found that IL-17 is produced within 1–2 d by tongue-resident populations of γδ T cells and CD3+CD4+CD44hiTCRβ+CCR6+ natural Th17 (nTh17) cells, but not by TCR-deficient innate lymphoid cells (ILCs) or NK cells. These cells function redundantly, as TCR-β−/− and TCR-δ−/− mice were both resistant to OPC. Whereas γδ T cells were previously shown to produce IL-17 during dermal candidiasis and are known to mediate host defense at mucosal surfaces, nTh17 cells are poorly understood. The oral nTh17 population expanded rapidly after OPC, exhibited high TCR-β clonal diversity, and was absent in Rag1−/−, IL-7Rα−/−, and germ-free mice. These findings indicate that nTh17 and γδ T cells, but not ILCs, are key mucosal sentinels that control oral pathogens.

scholarly journals Generation of a common innate lymphoid cell progenitor requires interferon regulatory factor 2

2019 ◽  
Vol 31 (8) ◽  
pp. 489-498 ◽  
Author(s):  
Yohei Okubo ◽  
Shigeo Tokumaru ◽  
Yuta Yamamoto ◽  
Shin-ichi Miyagawa ◽  
Hideki Sanjo ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Immune Surveillance ◽  
Interferon Regulatory Factor ◽  
Lymphoid Cells ◽  
Regulatory Factor ◽  
Lineage Specification ◽  
Temporal Regulation ◽  
Invariant Nkt Cells ◽  
Mucosal Surfaces ◽  
Unique Cell

Abstract Innate lymphoid cells (ILCs), composed of heterogeneous populations of lymphoid cells, contribute critically to immune surveillance at mucosal surfaces. ILC subsets develop from common lymphoid progenitors through stepwise lineage specification. However, the composition and temporal regulation of the transcription factor network governing such a process remain incompletely understood. Here, we report that deletion of the transcription factor interferon regulatory factor 2 (IRF-2), known also for its importance in the maturation of conventional NK cells, resulted in an impaired generation of ILC1, ILC2 and ILC3 subsets with lymphoid tissue inducer (LTi)-like cells hardly affected. In IRF-2-deficient mice, PD-1hi ILC precursors (ILCPs) that generate these three ILCs but not LTi-like cells were present at normal frequency, while their sub-population expressing high amounts of PLZF, another marker for ILCPs, was severely reduced. Notably, these IRF-2-deficient ILCPs contained normal quantities of PLZF-encoding Zbtb16 messages, and PLZF expression in developing invariant NKT cells within the thymus was unaffected in these mutant mice. These results point to a unique, cell-type selective role for IRF-2 in ILC development, acting at a discrete step critical for the generation of functionally competent ILCPs.

scholarly journals Bcl11b is essential for group 2 innate lymphoid cell development

2015 ◽  
Vol 212 (6) ◽  
pp. 875-882 ◽  
Author(s):  
Jennifer A. Walker ◽  
Christopher J. Oliphant ◽  
Alexandros Englezakis ◽  
Yong Yu ◽  
Simon Clare ◽  
...  
Keyword(s):  
Fetal Liver ◽  
Lymphoid Cells ◽  
Nippostrongylus Brasiliensis ◽  
Reporter Mice ◽  
Mucosal Surfaces ◽  
Gfp Reporter ◽  
Worm Expulsion ◽  
Group 2 ◽  
Cell Commitment

Group 2 innate lymphoid cells (ILC2s) are often found associated with mucosal surfaces where they contribute to protective immunity, inappropriate allergic responses, and tissue repair. Although we know they develop from a common lymphoid progenitor in the bone marrow (BM), the specific lineage path and transcriptional regulators that are involved are only starting to emerge. After ILC2 gene expression analysis we investigated the role of Bcl11b, a factor previously linked to T cell commitment, in ILC2 development. Using combined Bcl11b-tom and Id2-gfp reporter mice, we show that Bcl11b is expressed in ILC2 precursors in the BM and maintained in mature ILC2s. In vivo deletion of Bcl11b, by conditional tamoxifen-induced depletion or by Bcl11b−/− fetal liver chimera reconstitution, demonstrates that ILC2s are wholly dependent on Bcl11b for their development. Notably, in the absence of Bcl11b there is a concomitant expansion of the RORγt+ ILC3 population, suggesting that Bcl11b may negatively regulate this lineage. Using Nippostrongylus brasiliensis infection, we reveal that the absence of Bcl11b leads to impaired worm expulsion, caused by a deficit in ILC2s, whereas Citrobacter rodentium infection is cleared efficiently. These data clearly establish Bcl11b as a new factor in the differentiation of ILC2s.

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