A foldon-free prefusion F trimer vaccine for respiratory syncytial virus to reduce off-target immune responses.

Respiratory syncytial virus (RSV) is a major cause of severe respiratory disease in infants and older people. Current RSV subunit vaccines are based on a fusion protein that is stabilized in the prefusion conformation and linked to a heterologous foldon trimerization domain to obtain a prefusion F (preF) trimer. Here we show that current RSV vaccines induce undesirable anti-foldon antibodies in non-human primates, mice and humans.

Efficacious human metapneumovirus vaccine based on AI-guided engineering of a closed prefusion trimer.

The prefusion conformation of human metapneumovirus fusion protein (hMPV Pre-F) is critical for eliciting the most potent neutralizing antibodies and is the preferred immunogen for an efficacious vaccine against hMPV respiratory infections. Here we show that an additional cleavage event in the F protein allows closure and correct folding of the trimer. We therefore engineered the F protein to undergo double cleavage, which enabled screening for Pre-F stabilizing substitutions at the natively folded protomer interfaces.

Structural basis for potent neutralization of human respirovirus type 3 by protective single-domain camelid antibodies.

Respirovirus 3 is a leading cause of severe acute respiratory infections in vulnerable human populations. Entry into host cells is facilitated by the attachment glycoprotein and the fusion glycoprotein (F). Because of its crucial role, F represents an attractive therapeutic target.

Universal paramyxovirus vaccine design by stabilizing regions involved in structural transformation of the fusion protein.

The Paramyxoviridae family encompasses medically significant RNA viruses, including human respiroviruses 1 and 3 (RV1, RV3), and zoonotic pathogens like Nipah virus (NiV). RV3, previously known as parainfluenza type 3, for which no vaccines or antivirals have been approved, causes respiratory tract infections in vulnerable populations. The RV3 fusion (F) protein is inherently metastable and will likely require prefusion (preF) stabilization for vaccine effectiveness.

CoPoP liposomes displaying stabilized clade C HIV-1 Env elicit tier 2 multiclade neutralization in rabbits.

One of the strategies towards an effective HIV-1 vaccine is to elicit broadly neutralizing antibody responses that target the high HIV-1 Env diversity. Here, we present an HIV-1 vaccine candidate that consists of cobalt porphyrin-phospholipid (CoPoP) liposomes decorated with repaired and stabilized clade C HIV-1 Env trimers in a prefusion conformation. These particles exhibit high HIV-1 Env trimer decoration, serum stability and bind broadly neutralizing antibodies.

Design and Preclinical Evaluation of a Nanoparticle Vaccine against Respiratory Syncytial Virus Based on the Attachment Protein G.

Human respiratory syncytial virus (RSV) poses a significant human health threat, particularly to infants and the elderly. While efficacious vaccines based on the F protein have recently received market authorization, uncertainties remain regarding the future need for vaccine updates to counteract potential viral drift. The attachment protein G has long been ignored as a vaccine target due to perceived non-essentiality and ineffective neutralization on immortalized cells.

Enhancing breadth and durability of humoral immune responses in non-human primates with an adjuvanted group 1 influenza hemagglutinin stem antigen.

Seasonal influenza vaccines must be updated annually and suboptimally protect against strains mismatched to the selected vaccine strains. We previously developed a subunit vaccine antigen consisting of a stabilized trimeric influenza A group 1 hemagglutinin (H1) stem protein that elicits broadly neutralizing antibodies. Here, we further optimized the stability and manufacturability of the H1 stem antigen (H1 stem v2, also known as INFLUENZA G1 mHA) and characterized its formulation and potency with different adjuvants in vitro and in animal models.

Convergence of immune escape strategies highlights plasticity of SARS-CoV-2 spike.

The global spread of the SARS-CoV-2 virus has resulted in emergence of lineages which impact the effectiveness of immunotherapies and vaccines that are based on the early Wuhan isolate. All currently approved vaccines employ the spike protein S, as it is the target for neutralizing antibodies. Here we describe two SARS-CoV-2 isolates with unusually large deletions in the N-terminal domain (NTD) of the spike.

Combination Ad26.RSV.preF/preF protein vaccine induces superior protective immunity compared with individual vaccine components in preclinical models.

Respiratory syncytial virus (RSV) is a leading cause of severe respiratory disease for which no licensed vaccine is available. We have previously shown that a prefusion (preF) conformation-stabilized RSV F protein antigen and an adenoviral vector encoding RSV preF protein (Ad26.RSV.

Methodology for In Situ Microsensor Profiling of Hydrogen, pH, Oxidation-Reduction Potential, and Electric Potential throughout Three-Dimensional Porous Cathodes of (Bio)Electrochemical Systems.

We developed a technique based on the use of microsensors to measure pH and H gradients during microbial electrosynthesis. The use of 3D electrodes in (bio)electrochemical systems likely results in the occurrence of gradients from the bulk conditions into the electrode. Since these gradients, e.

An LPAR -antagonist that reduces nociception and increases pruriception.

Introduction: The G-protein coupled receptor LPAR plays a prominent role in LPA-mediated pain and itch signaling. In this study we focus on the LPAR-antagonist compound 3 (cpd3) and its ability to affect pain and itch signaling, both and .

Methods: Nociceptive behavior in wild type mice was induced by formalin, carrageenan or prostaglandin E2 (PGE) injection in the hind paw, and the effect of oral cpd3 administration was measured.

Universal stabilization of the influenza hemagglutinin by structure-based redesign of the pH switch regions.

For an efficacious vaccine immunogen, influenza hemagglutinin (HA) needs to maintain a stable quaternary structure, which is contrary to the inherently dynamic and metastable nature of class I fusion proteins. In this study, we stabilized HA with three substitutions within its pH-sensitive regions where the refolding starts. An X-ray structure reveals how these substitutions stabilize the intersubunit β-sheet in the base and form an interprotomeric aliphatic layer across the stem while the native prefusion HA fold is retained.

Immunogenicity and protective efficacy of adenoviral and subunit RSV vaccines based on stabilized prefusion F protein in pre-clinical models.

Respiratory Syncytial Virus (RSV) remains a leading cause of severe respiratory disease for which no licensed vaccine is available. We have previously described the derivation of an RSV Fusion protein (F) stabilized in its prefusion conformation (preF) as vaccine immunogen and demonstrated superior immunogenicity in naive mice of preF versus wild type RSV F protein, both as protein and when expressed from an Ad26 vaccine vector. Here we address the question if there are qualitative differences between the two vaccine platforms for induction of protective immunity.

Inhibition of autotaxin by bile salts and bile salt-like molecules increases its expression by feedback regulation.

Background: Autotaxin is an enzyme that converts lysophospholipid into lysophosphatidic acid (LPA), a highly potent signaling molecule through a range of LPA receptors. It is therefore important to investigate which factors play a role in regulating ATX expression. Since we have reported that ATX levels increase dramatically in patients with various forms of cholestasis, we embarked on a study to reveal factors that influence the enzyme activity ATX as well as its expression level in vitro and in vivo.

Ad26.COV2.S protects Syrian hamsters against G614 spike variant SARS-CoV-2 and does not enhance respiratory disease.

Previously we have shown that a single dose of recombinant adenovirus serotype 26 (Ad26) vaccine expressing a prefusion stabilized SARS-CoV-2 spike antigen (Ad26.COV2.S) is immunogenic and provides protection in Syrian hamster and non-human primate SARS-CoV-2 infection models.

Reduced spontaneous itch in mouse models of cholestasis.

Pruritus is one of the most distressing symptoms in cholestatic patients. Plasma autotaxin (ATX) activity correlates with the severity of pruritus in cholestatic patients, but the pathophysiology is unclear. To study pruritus in mice, we measured scratch activity in cholestatic Atp8b1 mutant mice, a model for Progressive Familial Intrahepatic Cholestasis type 1, and wild type mice (WT) with alpha-naphthylisothiocyanate (ANIT)-induced cholestasis.

Stabilizing the closed SARS-CoV-2 spike trimer.

The trimeric spike (S) protein of SARS-CoV-2 is the primary focus of most vaccine design and development efforts. Due to intrinsic instability typical of class I fusion proteins, S tends to prematurely refold to the post-fusion conformation, compromising immunogenic properties and prefusion trimer yields. To support ongoing vaccine development efforts, we report the structure-based design of soluble S trimers with increased yields and stabilities, based on introduction of single point mutations and disulfide-bridges.

Automated Design by Structure-Based Stabilization and Consensus Repair to Achieve Prefusion-Closed Envelope Trimers in a Wide Variety of HIV Strains.

Soluble envelope (Env) trimers, stabilized in a prefusion-closed conformation, can elicit neutralizing responses against HIV-1 strains closely related to the immunizing trimer. However, to date such stabilization has succeeded with only a limited number of HIV-1 strains. To address this issue, here we develop ADROITrimer, an automated procedure involving structure-based stabilization and consensus repair, and generate "RnS-DS-SOSIP"-stabilized Envs from 180 diverse Env sequences.

Ad26 vector-based COVID-19 vaccine encoding a prefusion-stabilized SARS-CoV-2 Spike immunogen induces potent humoral and cellular immune responses.

Development of effective preventative interventions against SARS-CoV-2, the etiologic agent of COVID-19 is urgently needed. The viral surface spike (S) protein of SARS-CoV-2 is a key target for prophylactic measures as it is critical for the viral replication cycle and the primary target of neutralizing antibodies. We evaluated design elements previously shown for other coronavirus S protein-based vaccines to be successful, e.