Human BST-2/tetherin inhibits Junin virus release from host cells and its inhibition is partially counteracted by viral nucleoprotein

Bone marrow stromal cell antigen-2 (BST-2), also known as tetherin, is an interferon-inducible membrane-associated protein. It effectively targets enveloped viruses at the release step of progeny viruses from host cells, thereby restricting the further spread of viral infection. Junin virus (JUNV) is a member of Arenaviridae, which causes Argentine haemorrhagic fever that is associated with a high rate of mortality. In this study, we examined the effect of human BST-2 on the replication and propagation of JUNV. The production of JUNV Z-mediated virus-like particles (VLPs) was significantly inhibited by over-expression of BST-2. Electron microscopy analysis revealed that BST-2 functions by forming a physical link that directly retains VLPs on the cell surface. Infection using JUNV showed that infectious JUNV production was moderately inhibited by endogenous or exogenous BST-2. We also observed that JUNV infection triggers an intense interferon response, causing an upregulation of BST-2, in infected cells. However, the expression of cell surface BST-2 was reduced upon infection. Furthermore, the expression of JUNV nucleoprotein (NP) partially recovered VLP production from BST-2 restriction, suggesting that the NP functions as an antagonist against antiviral effect of BST-2. We further showed that JUNV NP also rescued the production of Ebola virus VP40-mediated VLP from BST-2 restriction as a broad spectrum BST-2 antagonist. To our knowledge, this is the first report showing that an arenavirus protein counteracts the antiviral function of BST-2.

Download Full-text

Interferon response in the guinea pig infected with Junín virus

Journal of Medical Virology ◽

10.1002/jmv.1890230110 ◽

1987 ◽

Vol 23 (1) ◽

pp. 83-91 ◽

Cited By ~ 9

Author(s):

Cristina B. Dejean ◽

Bethy L. Ayerra ◽

Angélica R. Teyssié

Keyword(s):

Guinea Pig ◽

Interferon Response ◽

Junin Virus ◽

Junín Virus

Download Full-text

Utilization of human DC-SIGN and L-SIGN for entry and infection of host cells by the New World arenavirus, Junín virus

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2013.10.106 ◽

2013 ◽

Vol 441 (3) ◽

pp. 612-617 ◽

Cited By ~ 16

Author(s):

M.G. Martinez ◽

Michele A. Bialecki ◽

Sandrine Belouzard ◽

Sandra M. Cordo ◽

Nélida A. Candurra ◽

...

Keyword(s):

New World ◽

Host Cells ◽

Junin Virus ◽

Junín Virus

Download Full-text

Identification and Characterization of a Novel Broad-Spectrum Virus Entry Inhibitor

Journal of Virology ◽

10.1128/jvi.00103-16 ◽

2016 ◽

Vol 90 (9) ◽

pp. 4494-4510 ◽

Cited By ~ 13

Author(s):

Yi-ying Chou ◽

Christian Cuevas ◽

Margot Carocci ◽

Sarah H. Stubbs ◽

Minghe Ma ◽

...

Keyword(s):

Mouse Model ◽

Small Molecule ◽

Therapeutic Potential ◽

Virus Entry ◽

Small Gtpase ◽

Host Cells ◽

Entry Inhibitor ◽

Viral Fusion ◽

Junin Virus ◽

Junín Virus

ABSTRACTVirus entry into cells is a multistep process that often requires the subversion of subcellular machineries. A more complete understanding of these steps is necessary to develop new antiviral strategies. While studying the potential role of the actin network and one of its master regulators, the small GTPase Cdc42, during Junin virus (JUNV) entry, we serendipitously uncovered the small molecule ZCL278, reported to inhibit Cdc42 function as an entry inhibitor for JUNV and for vesicular stomatitis virus, lymphocytic choriomeningitis virus, and dengue virus but not for the nonenveloped poliovirus. Although ZCL278 did not interfere with JUNV attachment to the cell surface or virus particle internalization into host cells, it prevented the release of JUNV ribonucleoprotein cores into the cytosol and decreased pH-mediated viral fusion with host membranes. We also identified SVG-A astroglial cell-derived cells to be highly permissive for JUNV infection and generated new cell lines expressing fluorescently tagged Rab5c or Rab7a or lacking Cdc42 using clustered regularly interspaced short palindromic repeat (CRISPR)-caspase 9 (Cas9) gene-editing strategies. Aided by these tools, we uncovered that perturbations in the actin cytoskeleton or Cdc42 activity minimally affect JUNV entry, suggesting that the inhibitory effect of ZCL278 is not mediated by ZCL278 interfering with the activity of Cdc42. Instead, ZCL278 appears to redistribute viral particles from endosomal to lysosomal compartments. ZCL278 also inhibited JUNV replication in a mouse model, and no toxicity was detected. Together, our data suggest the unexpected antiviral activity of ZCL278 and highlight its potential for use in the development of valuable new tools to study the intracellular trafficking of pathogens.IMPORTANCEThe Junin virus is responsible for outbreaks of Argentine hemorrhagic fever in South America, where 5 million people are at risk. Limited options are currently available to treat infections by Junin virus or other viruses of theArenaviridae, making the identification of additional tools, including small-molecule inhibitors, of great importance. How Junin virus enters cells is not yet fully understood. Here we describe new cell culture models in which the cells are susceptible to Junin virus infection and to which we applied CRISPR-Cas9 genome engineering strategies to help characterize early steps during virus entry. We also uncovered ZCL278 to be a new antiviral small molecule that potently inhibits the cellular entry of the Junin virus and other enveloped viruses. Moreover, we show that ZCL278 also functionsin vivo, thereby preventing Junin virus replication in a mouse model, opening the possibility for the discovery of ZCL278 derivatives of therapeutic potential.

Download Full-text

Advances in Hepatitis E Virus Biology and Pathogenesis

Viruses ◽

10.3390/v13020267 ◽

2021 ◽

Vol 13 (2) ◽

pp. 267

Author(s):

Shaoli Lin ◽

Yan-Jin Zhang

Keyword(s):

Pregnant Women ◽

Hepatitis E Virus ◽

Case Fatality ◽

Hepatitis E ◽

Host Cells ◽

High Rate ◽

Rapid Progression ◽

Genotype 1 ◽

Genotype 3 ◽

Zoonotic Infections

Hepatitis E virus (HEV) is one of the causative agents for liver inflammation across the world. HEV is a positive-sense single-stranded RNA virus. Human HEV strains mainly belong to four major genotypes in the genus Orthohepevirus A, family Hepeviridae. Among the four genotypes, genotype 1 and 2 are obligate human pathogens, and genotype 3 and 4 cause zoonotic infections. HEV infection with genotype 1 and 2 mainly presents as acute and self-limiting hepatitis in young adults. However, HEV infection of pregnant women with genotype 1 strains can be exacerbated to fulminant hepatitis, resulting in a high rate of case fatality. As pregnant women maintain the balance of maternal-fetal tolerance and effective immunity against invading pathogens, HEV infection with genotype 1 might dysregulate the balance and cause the adverse outcome. Furthermore, HEV infection with genotype 3 can be chronic in immunocompromised patients, with rapid progression, which has been a challenge since it was reported years ago. The virus has a complex interaction with the host cells in downregulating antiviral factors and recruiting elements to generate a conducive environment of replication. The virus-cell interactions at an early stage might determine the consequence of the infection. In this review, advances in HEV virology, viral life cycle, viral interference with the immune response, and the pathogenesis in pregnant women are discussed, and perspectives on these aspects are presented.

Download Full-text

Legionella pneumophila DotU and IcmF Are Required for Stability of the Dot/Icm Complex

Infection and Immunity ◽

10.1128/iai.72.10.5983-5992.2004 ◽

2004 ◽

Vol 72 (10) ◽

pp. 5983-5992 ◽

Cited By ~ 56

Author(s):

Jessica A. Sexton ◽

Jennifer L. Miller ◽

Aki Yoneda ◽

Thomas E. Kehl-Fie ◽

Joseph P. Vogel

Keyword(s):

Cell Surface ◽

Legionella Pneumophila ◽

Bacterial Species ◽

Wide Distribution ◽

Host Cells ◽

Growth Defect ◽

Intracellular Growth ◽

Homologous Proteins ◽

Type Iv ◽

Cell Surface Structure

ABSTRACT Legionella pneumophila utilizes a type IV secretion system (T4SS) encoded by 26 dot/icm genes to replicate inside host cells and cause disease. In contrast to all other L. pneumophila dot/icm genes, dotU and icmF have homologs in a wide variety of gram-negative bacteria, none of which possess a T4SS. Instead, dotU and icmF orthologs are linked to a locus encoding a conserved cluster of proteins designated IcmF-associated homologous proteins, which has been proposed to constitute a novel cell surface structure. We show here that dotU is partially required for L. pneumophila intracellular growth, similar to the known requirement for icmF. In addition, we show that dotU and icmF are necessary for optimal plasmid transfer and sodium sensitivity, two additional phenotypes associated with a functional Dot/Icm complex. We found that these effects are due to the destabilization of the T4SS at the transition into the stationary phase, the point at which L. pneumophila becomes virulent. Specifically, three Dot proteins (DotH, DotG, and DotF) exhibit decreased stability in a ΔdotU ΔicmF strain. Furthermore, overexpression of just one of these proteins, DotH, is sufficient to suppress the intracellular growth defect of the ΔdotU ΔicmF mutant. This suggests a model where the DotU and IcmF proteins serve to prevent DotH degradation and therefore function to stabilize the L. pneumophila T4SS. Due to their wide distribution among bacterial species and their genetic linkage to known or predicted cell surface structures, we propose that this function in complex stabilization may be broadly conserved.

Download Full-text

A Single-Pass Type I Membrane Protein from the Apicomplexan Parasite Cryptosporidium parvum with Nanomolar Binding Affinity to Host Cell Surface

Microorganisms ◽

10.3390/microorganisms9051015 ◽

2021 ◽

Vol 9 (5) ◽

pp. 1015

Author(s):

Tianyu Zhang ◽

Xin Gao ◽

Dongqiang Wang ◽

Jixue Zhao ◽

Nan Zhang ◽

...

Keyword(s):

Membrane Protein ◽

Cell Surface ◽

Host Cell ◽

Binding Affinity ◽

Cryptosporidium Parvum ◽

Host Cells ◽

Watery Diarrhea ◽

Type I ◽

Single Pass ◽

Host Cell Surface

Cryptosporidium parvum is a globally recognized zoonotic parasite of medical and veterinary importance. This parasite mainly infects intestinal epithelial cells and causes mild to severe watery diarrhea that could be deadly in patients with weakened or defect immunity. However, its molecular interactions with hosts and pathogenesis, an important part in adaptation of parasitic lifestyle, remain poorly understood. Here we report the identification and characterization of a C. parvum T-cell immunomodulatory protein homolog (CpTIPH). CpTIPH is a 901-aa single-pass type I membrane protein encoded by cgd5_830 gene that also contains a short Vibrio, Colwellia, Bradyrhizobium and Shewanella (VCBS) repeat and relatively long integrin alpha (ITGA) N-terminus domain. Immunofluorescence assay confirmed the location of CpTIPH on the cell surface of C. parvum sporozoites. In congruence with the presence of VCBS repeat and ITGA domain, CpTIPH displayed high, nanomolar binding affinity to host cell surface (i.e., Kd(App) at 16.2 to 44.7 nM on fixed HCT-8 and CHO-K1 cells, respectively). The involvement of CpTIPH in the parasite invasion is partly supported by experiments showing that an anti-CpTIPH antibody could partially block the invasion of C. parvum sporozoites into host cells. These observations provide a strong basis for further investigation of the roles of CpTIPH in parasite-host cell interactions.

Download Full-text

Junin virus activity in two rural populations of the Argentine hemorrhagic fever (AHF) endemic area

Journal of Medical Virology ◽

10.1002/jmv.1890120407 ◽

1983 ◽

Vol 12 (4) ◽

pp. 273-280 ◽

Cited By ~ 15

Author(s):

Mercedes C. Weissenbacher ◽

Marta S. Sabattini ◽

María M. Avila ◽

Patricia M. Sangiorgio ◽

María R. F. De Sensi ◽

...

Keyword(s):

Endemic Area ◽

Hemorrhagic Fever ◽

Rural Populations ◽

Junin Virus ◽

Argentine Hemorrhagic Fever ◽

Virus Activity ◽

Junín Virus

Download Full-text

A Rapid Method for Detecting Junin Virus Viremia in the Guinea Pig

Intervirology ◽

10.1159/000148911 ◽

1977 ◽

Vol 8 (6) ◽

pp. 360-363 ◽

Cited By ~ 2

Author(s):

Adriana Rabinovich ◽

Patricio M. Cossio ◽

Guadalupe Carballal ◽

Roberto M. Arana

Keyword(s):

Guinea Pig ◽

Rapid Method ◽

Junin Virus ◽

Junín Virus

Download Full-text

Development of Peptide-Conjugated Morpholino Oligomers as Pan-Arenavirus Inhibitors

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00650-11 ◽

2011 ◽

Vol 55 (10) ◽

pp. 4631-4638 ◽

Cited By ~ 17

Author(s):

Benjamin W. Neuman ◽

Lydia H. Bederka ◽

David A. Stein ◽

Joey P. C. Ting ◽

Hong M. Moulton ◽

...

Keyword(s):

Cell Cultures ◽

Treatment Options ◽

Hemorrhagic Fever ◽

Virus Genome ◽

Lymphocytic Choriomeningitis ◽

Content Type ◽

Junin Virus ◽

Pichinde Virus ◽

Junín Virus

ABSTRACTMembers of theArenaviridaefamily are a threat to public health and can cause meningitis and hemorrhagic fever, and yet treatment options remain limited by a lack of effective antivirals. In this study, we found that peptide-conjugated phosphorodiamidate morpholino oligomers (PPMO) complementary to viral genomic RNA were effective in reducing arenavirus replication in cell cultures andin vivo. PPMO complementary to the Junín virus genome were designed to interfere with viral RNA synthesis or translation or both. However, only PPMO designed to potentially interfere with translation were effective in reducing virus replication. PPMO complementary to sequences that are highly conserved across the arenaviruses and located at the 5′ termini of both genomic segments were effective against Junín virus, Tacaribe virus, Pichinde virus, and lymphocytic choriomeningitis virus (LCMV)-infected cell cultures and suppressed viral titers in the livers of LCMV-infected mice. These results suggest that arenavirus 5′ genomic termini represent promising targets for pan-arenavirus antiviral therapeutic development.

Download Full-text