scholarly journals Exceptionally Potent Cross-Reactive Neutralization of Nipah and Hendra Viruses by a Human Monoclonal Antibody

2008 ◽  
Vol 197 (6) ◽  
pp. 846-853 ◽  
Author(s):  
Zhongyu Zhu ◽  
Katharine N Bossart ◽  
Kimberly A Bishop ◽  
Gary Crameri ◽  
Antony S Dimitrov ◽  
...  
Keyword(s):  
Therapeutic Agent ◽  
Human Monoclonal Antibody ◽  
Nipah Virus ◽  
Random Mutagenesis ◽  
Hendra Virus ◽  
Soluble Form ◽  
Antibody Library ◽  
Human Monoclonal Antibodies ◽  
Glycoprotein G ◽  
Better Than

Abstract We have previously identified neutralizing human monoclonal antibodies against Nipah virus (NiV) and Hendra virus (HeV) by panning a large nonimmune antibody library against a soluble form of the HeV attachment-envelope glycoprotein G (sGHeV). One of these antibodies, m102, which exhibited the highest level of cross-reactive neutralization of both NiV and HeV G, was affinity maturated by light-chain shuffling combined with random mutagenesis of its heavy-chain variable domain and panning against sGHeV. One of the selected antibody Fab clones, m102.4, had affinity of binding to sGHeV that was equal to or higher than that of the other Fabs; it was converted to IgG1 and tested against infectious NiV and HeV. It exhibited exceptionally potent and cross-reactive inhibitory activity with 50% inhibitory concentrations below 0.04 and 0.6 μg/mL, respectively. The virus-neutralizing activity correlated with the binding affinity of the antibody to sGHeV and sGNiV. m102.4 bound a soluble form of NiV G (sGNiV) better than it bound sGHeV, and it neutralized NiV better than HeV, despite being originally selected against sGHeV. These results suggest that m102.4 has potential as a therapeutic agent for the treatment of diseases caused by henipaviruses. It could be also used for prophylaxis and diagnosis, and as a research reagent

scholarly journals Potent Neutralization of Hendra and Nipah Viruses by Human Monoclonal Antibodies

2006 ◽  
Vol 80 (2) ◽  
pp. 891-899 ◽  
Author(s):  
Zhongyu Zhu ◽  
Antony S. Dimitrov ◽  
Katharine N. Bossart ◽  
Gary Crameri ◽  
Kimberly A. Bishop ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Cell Fusion ◽  
Hendra Virus ◽  
Soluble Form ◽  
Enzyme Linked Immunosorbent Assay ◽  
Human Antibody ◽  
Emerging Viruses ◽  
Human Monoclonal Antibodies ◽  
Initial Attempt ◽  
Fusion Event

ABSTRACT Hendra virus (HeV) and Nipah virus (NiV) are closely related emerging viruses comprising the Henipavirus genus of the Paramyxovirinae. Each has a broad species tropism and can cause disease with high mortality in both animal and human hosts. These viruses infect cells by a pH-independent membrane fusion event mediated by their attachment (G) and fusion (F) envelope glycoproteins (Envs). Seven Fabs, m101 to -7, were selected for their significant binding to a soluble form of Hendra G (sG) which was used as the antigen for panning of a large naïve human antibody library. The selected Fabs inhibited, to various degrees, cell fusion mediated by the HeV or NiV Envs and virus infection. The conversion of the most potent neutralizer of infectious HeV, Fab m101, to immunoglobulin G1 (IgG1) significantly increased its cell fusion inhibitory activity: the 50% inhibitory concentration was decreased more than 10-fold to approximately 1 μg/ml. The IgG1 m101 was also exceptionally potent in neutralizing infectious HeV; complete (100%) neutralization was achieved with 12.5 μg/ml, and 98% neutralization required only 1.6 μg/ml. The inhibition of fusion and infection correlated with binding of the Fabs to full-length G as measured by immunoprecipitation and less with binding to sG as measured by enzyme-linked immunosorbent assay and Biacore. m101 and m102 competed with the ephrin-B2, which we recently identified as a functional receptor for both HeV and NiV, indicating a possible mechanism of neutralization by these antibodies. The m101, m102, and m103 antibodies competed with each other, suggesting that they bind to overlapping epitopes which are distinct from the epitopes of m106 and m107. In an initial attempt to localize the epitopes of m101 and m102, we measured their binding to a panel of 11 G alanine-scanning mutants and identified two mutants, P185A and Q191 K192A, which significantly decreased binding to m101 and one, G183, which decreased binding of m102 to G. These results suggest that m101 to -7 are specific for HeV or NiV or both and exhibit various neutralizing activities; they are the first human monoclonal antibodies identified against these viruses and could be used for treatment, prophylaxis, and diagnosis and as research reagents and could aid in the development of vaccines.

scholarly journals Novel Functions of Hendra Virus G N-Glycans and Comparisons to Nipah Virus

2015 ◽  
Vol 89 (14) ◽  
pp. 7235-7247 ◽  
Author(s):  
Birgit G. Bradel-Tretheway ◽  
Qian Liu ◽  
Jacquelyn A. Stone ◽  
Samantha McInally ◽  
Hector C. Aguilar
Keyword(s):  
Membrane Fusion ◽  
Cell Fusion ◽  
Immune Evasion ◽  
Viral Entry ◽  
Nipah Virus ◽  
Hendra Virus ◽  
Viral Attachment ◽  
Glycoprotein G ◽  
Protein Functions ◽  
Cell Cell

ABSTRACTHendra virus (HeV) and Nipah virus (NiV) are reportedly the most deadly pathogens within theParamyxoviridaefamily. These two viruses bind the cellular entry receptors ephrin B2 and/or ephrin B3 via the viral attachment glycoprotein G, and the concerted efforts of G and the viral fusion glycoprotein F result in membrane fusion. Membrane fusion is essential for viral entry into host cells and for cell-cell fusion, a hallmark of the disease pathobiology. HeV G is heavily N-glycosylated, but the functions of the N-glycans remain unknown. We disrupted eight predicted N-glycosylation sites in HeV G by conservative mutations (Asn to Gln) and found that six out of eight sites were actually glycosylated (G2 to G7); one in the stalk (G2) and five in the globular head domain (G3 to G7). We then tested the roles of individual and combined HeV G N-glycan mutants and found functions in the modulation of shielding against neutralizing antibodies, intracellular transport, G-F interactions, cell-cell fusion, and viral entry. Between the highly conserved HeV and NiV G glycoproteins, similar trends in the effects of N-glycans on protein functions were observed, with differences in the levels at which some N-glycan mutants affected such functions. While the N-glycan in the stalk domain (G2) had roles that were highly conserved between HeV and NiV G, individual N-glycans in the head affected the levels of several protein functions differently. Our findings are discussed in the context of their contributions to our understanding of HeV and NiV pathogenesis and immune responses.IMPORTANCEViral envelope glycoproteins are important for viral pathogenicity and immune evasion. N-glycan shielding is one mechanism by which immune evasion can be achieved. In paramyxoviruses, viral attachment and membrane fusion are governed by the close interaction of the attachment proteins H/HN/G and the fusion protein F. In this study, we show that the attachment glycoprotein G of Hendra virus (HeV), a deadly paramyxovirus, is N-glycosylated at six sites (G2 to G7) and that most of these sites have important roles in viral entry, cell-cell fusion, G-F interactions, G oligomerization, and immune evasion. Overall, we found that the N-glycan in the stalk domain (G2) had roles that were very conserved between HeV G and the closely related Nipah virus G, whereas individual N-glycans in the head quantitatively modulated several protein functions differently between the two viruses.

scholarly journals A Cross-Reactive Humanized Monoclonal Antibody Targeting Fusion Glycoprotein Function Protects Ferrets Against Lethal Nipah Virus and Hendra Virus Infection

2019 ◽  
Vol 221 (Supplement_4) ◽  
pp. S471-S479 ◽  
Author(s):  
Chad E Mire ◽  
Yee-Peng Chan ◽  
Viktoriya Borisevich ◽  
Robert W Cross ◽  
Lianying Yan ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Virus Infection ◽  
Severe Disease ◽  
Human Monoclonal Antibody ◽  
Nipah Virus ◽  
Antibody Therapy ◽  
Hendra Virus ◽  
High Dose ◽  
Virus Challenge

Abstract Background Nipah virus (NiV) and Hendra virus (HeV) are zoonotic paramyxoviruses that cause severe disease in both animals and humans. There are no approved vaccines or treatments for use in humans; however, therapeutic treatment of both NiV and HeV infection in ferrets and non-human primates with a cross-reactive, neutralizing human monoclonal antibody (mAb), m102.4, targeting the G glycoprotein has been demonstrated. In a previous study, we isolated, characterized, and humanized a cross-reactive, neutralizing anti-F mAb (h5B3.1). The mAb h5B3.1 blocks the required F conformational change needed to facilitate membrane fusion and virus infection, and the epitope recognized by h5B3.1 has been structurally defined; however, the efficacy of h5B3.1 in vivo is unknown. Methods The post-infection antiviral activity of h5B3.1 was evaluated in vivo by administration in ferrets after NiV and HeV virus challenge. Results All subjects that received h5B3.1 from 1 to several days after infection with a high-dose, oral-nasal virus challenge were protected from disease, whereas all controls died. Conclusions This is the first successful post-exposure antibody therapy for NiV and HeV using a humanized cross-reactive mAb targeting the F glycoprotein, and the findings suggest that a combination therapy targeting both F and G should be evaluated as a therapy for NiV/HeV infection.

scholarly journals Functional Analysis of the Fusion and Attachment Glycoproteins of Mojiang Henipavirus

Viruses ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 517
Author(s):  
Sofia Cheliout Da Silva ◽  
Lianying Yan ◽  
Ha V. Dang ◽  
Kai Xu ◽  
Jonathan H. Epstein ◽  
...  
Keyword(s):  
Functional Analysis ◽  
Cell Fusion ◽  
Sequence Data ◽  
Nipah Virus ◽  
Hendra Virus ◽  
Soluble Form ◽  
Fusion Activity ◽  
Low Levels ◽  
Entry Receptor ◽  
Functional Defects

Mojiang virus (MojV) is the first henipavirus identified in a rodent and known only by sequence data, whereas all other henipaviruses have been isolated from bats (Hendra virus, Nipah virus, Cedar virus) or discovered by sequence data from material of bat origin (Ghana virus). Ephrin-B2 and -B3 are entry receptors for Hendra and Nipah viruses, but Cedar virus can utilize human ephrin-B1, -B2, -A2 and -A5 and mouse ephrin-A1. However, the entry receptor for MojV remains unknown, and its species tropism is not well characterized. Here, we utilized recombinant full-length and soluble forms of the MojV fusion (F) and attachment (G) glycoproteins in membrane fusion and receptor tropism studies. MojV F and G were functionally competent and mediated cell–cell fusion in primate and rattine cells, albeit with low levels and slow fusion kinetics. Although a relative instability of the pre-fusion conformation of a soluble form of MojV F was observed, MojV F displayed significantly greater fusion activity when heterotypically paired with Ghana virus G. An exhaustive investigation of A- and B-class ephrins indicated that none serve as a primary receptor for MojV. The MojV cell fusion phenotype is therefore likely the result of receptor restriction rather than functional defects in recombinant MojV F and G glycoproteins.

scholarly journals Chloroquine Administration Does Not Prevent Nipah Virus Infection and Disease in Ferrets

2009 ◽  
Vol 83 (22) ◽  
pp. 11979-11982 ◽  
Author(s):  
Jackie Pallister ◽  
Deborah Middleton ◽  
Gary Crameri ◽  
Manabu Yamada ◽  
Reuben Klein ◽  
...  
Keyword(s):  
Virus Infection ◽  
Nipah Virus ◽  
Disease Outbreaks ◽  
Mortality Rates ◽  
Hendra Virus ◽  
Malaria Therapy ◽  
Sporadic Disease

ABSTRACT Hendra virus and Nipah virus, two zoonotic paramyxoviruses in the genus Henipavirus, have recently emerged and continue to cause sporadic disease outbreaks in humans and animals. Mortality rates of up to 75% have been reported in humans, but there are presently no clinically licensed therapeutics for treating henipavirus-induced disease. A recent report indicated that chloroquine, used in malaria therapy for over 70 years, prevented infection with Nipah virus in vitro. Chloroquine was assessed using a ferret model of lethal Nipah virus infection and found to be ineffective against Nipah virus infection in vivo.

scholarly journals A Quantitative and Kinetic Fusion Protein-Triggering Assay Can Discern Distinct Steps in the Nipah Virus Membrane Fusion Cascade

2010 ◽  
Vol 84 (16) ◽  
pp. 8033-8041 ◽  
Author(s):  
Hector C. Aguilar ◽  
Vanessa Aspericueta ◽  
Lindsey R. Robinson ◽  
Karen E. Aanensen ◽  
Benhur Lee
Keyword(s):  
Membrane Fusion ◽  
Receptor Binding ◽  
Nipah Virus ◽  
Heptad Repeat ◽  
Critical Parameters ◽  
Second Phase ◽  
Two Phase ◽  
Glycoprotein G ◽  
Fusion Glycoprotein ◽  
Functional Features

ABSTRACT The deadly paramyxovirus Nipah virus (NiV) contains a fusion glycoprotein (F) with canonical structural and functional features common to its class. Receptor binding to the NiV attachment glycoprotein (G) triggers F to undergo a two-phase conformational cascade: the first phase progresses from a metastable prefusion state to a prehairpin intermediate (PHI), while the second phase is marked by transition from the PHI to the six-helix-bundle hairpin. The PHI can be captured with peptides that mimic F's heptad repeat regions, and here we utilized a NiV heptad repeat peptide to quantify PHI formation and the half-lives (t 1/2) of the first and second fusion cascade phases. We found that ephrinB2 receptor binding to G triggered ∼2-fold more F than that triggered by ephrinB3, consistent with the increased rate and extent of fusion observed with ephrinB2- versus ephrinB3-expressing cells. In addition, for a series of hyper- and hypofusogenic F mutants, we quantified F-triggering capacities and measured the kinetics of their fusion cascade phases. Hyper- and hypofusogenicity can each be manifested through distinct stages of the fusion cascade, giving rise to vastly different half-lives for the first (t 1/2, 1.9 to 7.5 min) or second (t 1/2, 1.5 to 15.6 min) phase. While three mutants had a shorter first phase and a longer second phase than the wild-type protein, one mutant had the opposite phenotype. Thus, our results reveal multiple critical parameters that govern the paramyxovirus fusion cascade, and our assays should help efforts to elucidate other class I membrane fusion processes.

scholarly journals Antioxidant Activity, Phenolic Profile, and Nephroprotective Potential of Anastatica hierochuntica Ethanolic and Aqueous Extracts against CCl4-Induced Nephrotoxicity in Rats

Nutrients ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 2973
Author(s):  
Tariq I. Almundarij ◽  
Yousef M. Alharbi ◽  
Hassan A. Abdel-Rahman ◽  
Hassan Barakat
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Activity ◽  
Therapeutic Agent ◽  
Kidney Tissue ◽  
Kidney Injury ◽  
Total Phenolic ◽  
Drug Induced ◽  
Total Carotenoids ◽  
Phenolic Profile ◽  
Better Than

Kaff-e-Maryam (Anastatica hierochuntica L.) is extensively used to treat a range of health problems, most notably to ease childbirth and alleviate reproductive system-related disorders. This study aimed to evaluate the effect of A. hierochuntica ethanolic (KEE), and aqueous (KAE) extracts on CCl4-induced oxidative stress and nephrotoxicity in rats using the biochemical markers for renal functions and antioxidant status as well as histopathological examinations of kidney tissue. A. hierochuntica contained 67.49 mg GAE g−1 of total phenolic compounds (TPC), 3.51 µg g−1 of total carotenoids (TC), and 49.78 and 17.45 mg QE g−1 of total flavonoids (TF) and total flavonols (TFL), respectively. It resulted in 128.71 µmol of TE g−1 of DPPH-RSA and 141.92 µmol of TE g−1 of ABTS-RSA. A. hierochuntica presented superior antioxidant activity by inhibiting linoleic acid radicals and chelating oxidation metals. The HPLC analysis resulted in 9 and 21 phenolic acids and 6 and 2 flavonoids in KEE and KAE with a predominance of sinapic and syringic acids, respectively. Intramuscular injection of vit. E + Se and oral administration of KEE, KAE, and KEE + KAE at 250 mg kg−1 body weight significantly restored serum creatinine, urea, K, total protein, and albumin levels. Additionally, they reduced malondialdehyde (MOD), restored reduced-glutathione (GSH), and enhanced superoxide dismutase (SOD) levels. KEE, KAE, and KEE + KAE protected the kidneys from CCl4-nephrotoxicity as they mainly attenuated induced oxidative stress. Total nephroprotection was about 83.27%, 97.62%, and 78.85% for KEE, KAE, and KEE + KAE, respectively. Both vit. E + Se and A. hierochuntica extracts attenuated the histopathological alteration in CCl4-treated rats. In conclusion, A. hierochuntica, especially KAE, has the potential capability to restore oxidative stability and improve kidney function after CCl4 acute kidney injury better than KEE. Therefore, A. hierochuntica has the potential to be a useful therapeutic agent in the treatment of drug-induced nephrotoxicity.

scholarly journals From The Cover: Ephrin-B2 ligand is a functional receptor for Hendra virus and Nipah virus

2005 ◽  
Vol 102 (30) ◽  
pp. 10652-10657 ◽  
Author(s):  
M. I. Bonaparte ◽  
A. S. Dimitrov ◽  
K. N. Bossart ◽  
G. Crameri ◽  
B. A. Mungall ◽  
...  
Keyword(s):  
Nipah Virus ◽  
Hendra Virus ◽  
Functional Receptor
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