scholarly journals Highly Pathogenic New World and Old World Human Arenaviruses Induce Distinct Interferon Responses in Human Cells

2015 ◽  
Vol 89 (14) ◽  
pp. 7079-7088 ◽  
Author(s):  
Cheng Huang ◽  
Olga A. Kolokoltsova ◽  
Nadezhda E. Yun ◽  
Alexey V. Seregin ◽  
Shannon Ronca ◽  
...  

ABSTRACTThe arenavirus family includes several important pathogens that cause severe and sometimes fatal diseases in humans. The highly pathogenic Old World (OW) arenavirus Lassa fever virus (LASV) is the causative agent of Lassa fever (LF) disease in humans. LASV infections in severe cases are generally immunosuppressive without stimulating interferon (IFN) induction, a proinflammatory response, or T cell activation. However, the host innate immune responses to highly pathogenic New World (NW) arenaviruses are not well understood. We have previously shown that the highly pathogenic NW arenavirus, Junin virus (JUNV), induced an IFN response in human A549 cells. Here, we report that Machupo virus (MACV), another highly pathogenic NW arenavirus, also induces an IFN response. Importantly, both pathogenic NW arenaviruses, in contrast to the OW highly pathogenic arenavirus LASV, readily elicited an IFN response in human primary dendritic cells and A549 cells. Coinfection experiments revealed that LASV could potently inhibit MACV-activated IFN responses even at 6 h after MACV infection, while the replication levels of MACV and LASV were not affected by virus coinfection. Our results clearly demonstrated that although all viruses studied herein are highly pathogenic to humans, the host IFN responses toward infections with the NW arenaviruses JUNV and MACV are quite different from responses to infections with the OW arenavirus LASV, a discovery that needs to be further investigated in relevant animal models. This finding might help us better understand various interplays between the host immune system and highly pathogenic arenaviruses as well as distinct mechanisms underlying viral pathogenesis.IMPORTANCEInfections of humans with the highly pathogenic OW LASV are accompanied by potent suppression of interferon or proinflammatory cytokine production. In contrast, infections with the highly pathogenic NW arenavirus JUNV are associated with high levels of IFNs and cytokines in severe and fatal cases. Arenaviruses initially target macrophages and dendritic cells, which are potent IFN/cytokine-producers. In human macrophages, JUNV reportedly does not trigger IFN responses. We here demonstrated that JUNV activated IFN responses in human dendritic cells. MACV, another highly pathogenic NW arenavirus, also activated IFN responses. LASV did not induce detectable IFN responses, in spite of higher replication levels, and blocked the MACV-triggered IFN response in a coinfection assay. Although these viruses are highly pathogenic to humans, our study highlights distinct innate immune responses to infections with the NW arenaviruses JUNV and MACV and to infection with the OW arenavirus LASV and provides important insights into the virus-host interaction and pathogenesis.

2005 ◽  
Vol 79 (21) ◽  
pp. 13800-13805 ◽  
Author(s):  
Thedi Ziegler ◽  
Sampsa Matikainen ◽  
Esa Rönkkö ◽  
Pamela Österlund ◽  
Maarit Sillanpää ◽  
...  

ABSTRACT Activation of host innate immune responses was studied in severe acute respiratory syndrome coronavirus (SCV)-infected human A549 lung epithelial cells, macrophages, and dendritic cells (DCs). In all cell types, SCV-specific subgenomic mRNAs were seen, whereas no expression of SCV proteins was found. No induction of cytokine genes (alpha interferon [IFN-α], IFN-β, interleukin-28A/B [IL-28A/B], IL-29, tumor necrosis factor alpha, CCL5, or CXCL10) or IFN-α/β-induced MxA gene was seen in SCV-infected A549 cells, macrophages, or DCs. SCV also failed to induce DC maturation (CD86 expression) or enhance major histocompatibility complex class II expression. Our data strongly suggest that SCV fails to activate host cell cytokine gene expression in human macrophages and DCs.


2019 ◽  
Vol 93 (19) ◽  
Author(s):  
Hector Moreno ◽  
Rebecca Möller ◽  
Chiara Fedeli ◽  
Gisa Gerold ◽  
Stefan Kunz

ABSTRACT The New World (NW) arenaviruses are a diverse group of zoonotic viruses, including several causative agents of severe hemorrhagic fevers in humans. All known human-pathogenic NW arenaviruses belong to clade B, where they group into sublineages with phylogenetically closely related nonpathogenic viruses, e.g., the highly pathogenic Junin (JUNV) and Machupo viruses with the nonpathogenic Tacaribe virus (TCRV). Considering the close genetic relationship of nonpathogenic and pathogenic NW arenaviruses, the identification of molecular determinants of virulence is of great importance. The host cell’s innate antiviral defense represents a major barrier for zoonotic infection. Here, we performed a side-by-side comparison of the innate immune responses against JUNV and TCRV in human cells. Despite similar levels of viral replication, infection with TCRV consistently induced a stronger type I interferon (IFN-I) response than JUNV infection did. Transcriptome profiling revealed upregulation of a largely overlapping set of interferon-stimulated genes in cells infected with TCRV and JUNV. Both viruses were relatively insensitive to IFN-I treatment of human cells and induced similar levels of apoptosis in the presence or absence of an IFN-I response. However, in comparison to JUNV, TCRV induced stronger activation of the innate sensor double-strand RNA-dependent protein kinase R (PKR), resulting in phosphorylation of eukaryotic translation initiation factor eIF2α. Confocal microscopy studies revealed similar subcellular colocalizations of the JUNV and TCRV viral replication-transcription complexes with PKR. However, deletion of PKR by CRISPR/Cas9 hardly affected JUNV but promoted TCRV multiplication, providing the first evidence for differential innate recognition and control of pathogenic and nonpathogenic NW arenaviruses by PKR. IMPORTANCE New World (NW) arenaviruses are a diverse family of emerging zoonotic viruses that merit significant attention as important public health problems. The close genetic relationship of nonpathogenic NW arenaviruses with their highly pathogenic cousins suggests that few mutations may be sufficient to enhance virulence. The identification of molecular determinants of virulence of NW arenaviruses is therefore of great importance. Here we undertook a side-by-side comparison of the innate immune responses against the highly pathogenic Junin virus (JUNV) and the related nonpathogenic Tacaribe virus (TCRV) in human cells. We consistently found that TCRV induces a stronger type I interferon (IFN-I) response than JUNV. Transcriptome profiling revealed an overlapping pattern of IFN-induced gene expression and similar low sensitivities to IFN-I treatment. However, the double-stranded RNA (dsRNA)-dependent protein kinase R (PKR) contributed to the control of TCRV, but not JUNV, providing the first evidence for differential innate recognition and control of JUNV and TCRV.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Melanie R. Neeland ◽  
Samantha Bannister ◽  
Vanessa Clifford ◽  
Kate Dohle ◽  
Kim Mulholland ◽  
...  

AbstractChildren have mild severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) confirmed disease (COVID-19) compared to adults and the immunological mechanisms underlying this difference remain unclear. Here, we report acute and convalescent innate immune responses in 48 children and 70 adults infected with, or exposed to, SARS-CoV-2. We find clinically mild SARS-CoV-2 infection in children is characterised by reduced circulating subsets of monocytes (classical, intermediate, non-classical), dendritic cells and natural killer cells during the acute phase. In contrast, SARS-CoV-2-infected adults show reduced proportions of non-classical monocytes only. We also observe increased proportions of CD63+ activated neutrophils during the acute phase to SARS-CoV-2 in infected children. Children and adults exposed to SARS-CoV-2 but negative on PCR testing display increased proportions of low-density neutrophils that we observe up to 7 weeks post exposure. This study characterises the innate immune response during SARS-CoV-2 infection and household exposure in children.


2015 ◽  
Vol 96 (2) ◽  
pp. 294-310 ◽  
Author(s):  
Trina Das ◽  
Jean Jacques Hoarau ◽  
Marie Christine Jaffar Bandjee ◽  
Marianne Maquart ◽  
Philippe Gasque

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Pamela Österlund ◽  
Miao Jiang ◽  
Veera Westenius ◽  
Suvi Kuivanen ◽  
Riia Järvi ◽  
...  

Abstract Zika virus (ZIKV) infections in humans are considered to be mild or subclinical. However, during the recent epidemics in the Pacific Islands and the Americas, the infection was associated with Quillain-Barré syndrome and congenital infections with fetal brain abnormalities, including microcephaly. Thus, more detailed understanding of ZIKV-host cell interactions and regulation of innate immune responses by strains of differential evolutionary origin is required. Here, we characterized the infection and immune responses triggered by two epidemic Asian/American lineage viruses, including an isolate from fetal brains, and a historical, low passage 1947 African lineage virus in human monocyte-derived dendritic cells (DCs) and macrophages. The epidemic Asian/American ZIKV replicated well and induced relatively good antiviral responses in human DCs whereas the African strain replicated less efficiently and induced weaker immune responses. In macrophages both the African and Asian strains showed limited replication and relatively weak cytokine gene expression. Interestingly, in macrophages we observed host protein degradation, especially IRF3 and STAT2, at early phases of infection with both lineage viruses, suggesting an early proteasomal activation in phagocytic cells. Our data indicates that ZIKV evolution has led to significant phenotypic differences in the replication characteristics leading to differential regulation of host innate immune responses.


2020 ◽  
Vol 11 ◽  
Author(s):  
Hanaa Ahmed-Hassan ◽  
Brianna Sisson ◽  
Rajni Kant Shukla ◽  
Yasasvi Wijewantha ◽  
Nicholas T. Funderburg ◽  
...  

Vaccines ◽  
2019 ◽  
Vol 7 (4) ◽  
pp. 138 ◽  
Author(s):  
Mantlo ◽  
Paessler ◽  
Huang

The family Arenaviridae contains several pathogens of major clinical importance. The Old World (OW) arenavirus Lassa virus is endemic in West Africa and is estimated to cause up to 300,000 infections each year. The New World (NW) arenaviruses Junín and Machupo periodically cause hemorrhagic fever outbreaks in South America. While these arenaviruses are highly pathogenic in humans, recent evidence indicates that pathogenic OW and NW arenaviruses interact with the host immune system differently, which may have differential impacts on viral pathogenesis. Severe Lassa fever cases are characterized by profound immunosuppression. In contrast, pathogenic NW arenavirus infections are accompanied by elevated levels of Type I interferon and pro-inflammatory cytokines. This review aims to summarize recent findings about interactions of these pathogenic arenaviruses with the innate immune machinery and the subsequent effects on adaptive immunity, which may inform the development of vaccines and therapeutics against arenavirus infections.


2020 ◽  
Vol 94 (9) ◽  
Author(s):  
Elizabeth J. Mateer ◽  
Junki Maruyama ◽  
Galen E. Card ◽  
Slobodan Paessler ◽  
Cheng Huang

ABSTRACT The arenaviruses Lassa virus (LASV), Junín virus (JUNV), and Machupo virus (MACV) can cause severe and fatal diseases in humans. Although these pathogens are closely related, the host immune responses to these virus infections differ remarkably, with direct implications for viral pathogenesis. LASV infection is immunosuppressive, with a very low-level interferon response. In contrast, JUNV and MACV infections stimulate a robust interferon (IFN) response in a retinoic acid-inducible gene I (RIG-I)-dependent manner and readily activate protein kinase R (PKR), a known host double-stranded RNA (dsRNA) sensor. In response to infection with RNA viruses, host nonself RNA sensors recognize virus-derived dsRNA as danger signals and initiate innate immune responses. Arenavirus nucleoproteins (NPs) contain a highly conserved exoribonuclease (ExoN) motif, through which LASV NP has been shown to degrade virus-derived immunostimulatory dsRNA in biochemical assays. In this study, we for the first time present evidence that LASV restricts dsRNA accumulation during infection. Although JUNV and MACV NPs also have the ExoN motif, dsRNA readily accumulated in infected cells and often colocalized with dsRNA sensors. Moreover, LASV coinfection diminished the accumulation of dsRNA and the IFN response in JUNV-infected cells. The disruption of LASV NP ExoN with a mutation led to dsRNA accumulation and impaired LASV replication in minigenome systems. Importantly, both LASV NP and RNA polymerase L protein were required to diminish the accumulation of dsRNA and the IFN response in JUNV infection. For the first time, we discovered a collaboration between LASV NP ExoN and L protein in limiting dsRNA accumulation. Our new findings provide mechanistic insights into the differential host innate immune responses to highly pathogenic arenavirus infections. IMPORTANCE Arenavirus NPs contain a highly conserved DEDDh ExoN motif, through which LASV NP degrades virus-derived, immunostimulatory dsRNA in biochemical assays to eliminate the danger signal and inhibit the innate immune response. Nevertheless, the function of NP ExoN in arenavirus infection remains to be defined. In this study, we discovered that LASV potently restricts dsRNA accumulation during infection and minigenome replication. In contrast, although the NPs of JUNV and MACV also harbor the ExoN motif, dsRNA readily formed during JUNV and MACV infections, accompanied by IFN and PKR responses. Interestingly, LASV NP alone was not sufficient to limit dsRNA accumulation. Instead, both LASV NP and L protein were required to restrict immunostimulatory dsRNA accumulation. Our findings provide novel and important insights into the mechanism for the distinct innate immune response to these highly pathogenic arenaviruses and open new directions for future studies.


Sign in / Sign up

Export Citation Format

Share Document