Venezuelan equine encephalitis virus non-structural protein 3 dictates superinfection exclusion in mammalian cells DOI Creative Commons
Tessy A. H. Hick,

Taja Zotler,

Davita Bosveld

et al.

npj Viruses, Journal Year: 2024, Volume and Issue: 2(1)

Published: Sept. 13, 2024

Superinfection exclusion (SIE) prevents secondary infections of already infected cells. Arthritogenic alphaviruses induce SIE via early proteolytical cleavage replicase precursor by non-structural protein 2 (nsP2). Here, we explore the mechanism encephalitic Venezuelan equine encephalitis virus (VEEV). Using single-cell imaging techniques and VEEV replicons encoding green or red fluorescent proteins, observed full capacity in three hours. Transient expression nsP3, but not nsP2, reduced alphavirus replication, suggesting a key role for nsP3 mechanism. In particular, C-terminal hypervariable domain (HVD) was found to be required sufficient more distantly related Sindbis virus. As HVD is known bind multiple host proteins form RNA replication complexes modulate cellular stress response, propose that sequestering essential protein(s) interferes with superinfecting alphavirus.

Language: Английский

Self-Amplifying RNA: Advantages and Challenges of a Versatile Platform for Vaccine Development DOI Creative Commons
Thomas Vallet,

Marco Vignuzzi

Viruses, Journal Year: 2025, Volume and Issue: 17(4), P. 566 - 566

Published: April 14, 2025

Self-amplifying RNA is synthetic nucleic acid engineered to replicate within cells without generating viral particles. Derived from alphavirus genomes, saRNA retains the non-structural elements essential for replication while replacing structural with an antigen of interest. By enabling efficient intracellular amplification, offers a promising alternative conventional mRNA vaccines, enhancing expression requiring lower doses. However, this advantage comes challenges. In review, we highlight key limitations technology and explore potential strategies overcome them. identifying these challenges, aim provide insights that can guide future design saRNA-based therapeutics, extending their beyond vaccine applications.

Language: Английский

Citations

2
Packaging of alphavirus-based self-amplifying mRNA yields replication-competent virus through a mechanism of aberrant homologous RNA recombination DOI Creative Commons
Tessy A. H. Hick,

Corinne Geertsema,

Reindert Nijland

et al.

mBio, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 25, 2024

ABSTRACT Messenger (m)RNA has taken center stage in vaccine development, gene therapy, and cancer immunotherapy. A next-generation of mRNA is the self-amplifying (sa)mRNA, which induces broad long-lasting immunity at a lower dose provides better clinical outcomes conjunction with fewer adverse effects. SamRNA, also known as “replicon” RNA, encodes replication machinery an alphavirus together antigen. Efficient delivery replicon RNA to target tissues can be accomplished by packaging virus-like particles (VRPs) via co-transfection producer cells defective helper RNA(s) encoding structural proteins. During manufacture VRPs, however, there potential risk recombination, may lead formation replication-competent virus (RCV). To investigate factors influencing unwanted RCV formation, we evaluated how sequence homology orchestrates recombination. Several combinations complementing RNAs varying length sequences overlap were co-transfected mammalian cells. The culture fluid was serially passaged detect RCV. Nanopore sequencing after first passage combination amplicon-based Sanger four passages led detection generated between either non-structural or genes, whereas without overlapping regions did not generate Remarkably, no detected recombination junction sites genome, suggesting mechanism “aberrant homologous recombination.” Accordingly, conclude that process leading homology-assisted prevented avoiding RNAs. IMPORTANCE There growing interest use (sa)mRNA vectors for samRNA form enables efficient tissue. production these suffers from contamination (RCV) thought arise events VRP packaging. presence product undesirable alphaviruses cause serious disease humans. However, underlying currently unknown. In our work, demonstrate detailed evaluation sites, indicates formed through unusual results are useful researchers field delivery.

Language: Английский

Citations

3
Insect-specific virus platforms for arbovirus vaccine development DOI Creative Commons
Roy A. Hall, Wilson Nguyen, Alexander A. Khromykh

et al.

Frontiers in Immunology, Journal Year: 2025, Volume and Issue: 16

Published: March 14, 2025

Certain insect-specific viruses (ISVs), specifically the mosquito alphaviruses, Eilat and Yada viruses, orthoflaviviruses, Binjari, Aripo, YN15-283-02 Chaoyang have emerged as potential platforms for generation of whole virus vaccines human veterinary applications. These ISVs are remarkably tolerant substitution their structural polyproteins with those alphaviruses orthoflaviviruses that pathogenic in humans and/or animals. The resulting ISV-based chimeric been evaluated mouse models demonstrated safety efficacy non-human primates, crocodiles pigs. Targets include chikungunya, Venezuelan eastern equine encephalitis, dengue, Zika, yellow fever, Japanese encephalitis West Nile viruses. provide authentically folded tertiary quaternary virion particle structures to immune system, a key feature induction protective antibody responses. manufactured C6/36 or C7-10 cell lines, where they grow high titers, but do not replicate vertebrate vaccine recipients. This review discusses progress these emerging technologies addresses challenges related adjuvanting, safety, manufacturing.

Language: Английский

Citations

0
The Potential of Extracellular Vesicle-Mediated Spread of Self-Amplifying RNA and a Way to Mitigate It DOI Open Access
Maurizio Federico

International Journal of Molecular Sciences, Journal Year: 2025, Volume and Issue: 26(11), P. 5118 - 5118

Published: May 26, 2025

Self-amplifying RNA-based (saRNA) technology represents the last frontier in using synthetic RNA vaccinology. Typically, saRNA consists of positive-strand molecules viral origin (almost exclusively from alphaviruses) where sequences structural proteins are replaced with open reading frame coding antigen interest. For vivo delivery, they complexed lipid nanoparticles (LNPs), just like current COVID-19 vaccines based on messenger (mRNA). Given their ability to amplify themselves inside cell, optimal intracellular levels immunogenic can be achieved by delivering lower amounts compared mRNA-based vaccines. However, excessive accumulation may represent a relevant drawback since, as already described alphavirus-infected cells, recipient cell react incorporating into extracellular vesicles (EVs). These EVs shed and enter neighboring well distant EV-associated start new replication cycle. This mechanism could lead an unwanted unnecessary spread throughout body, posing safety issues. perspective article discusses molecular mechanisms through which saRNAs transmitted among different cells/tissues. In addition, simple way control possible intercellular propagation co-expression EV-anchored protein inhibiting is proposed. Based knowledge, improvement saRNA-based appears mandatory for usage healthy humans.

Language: Английский

Citations

0
Can self-amplifying RNA vaccines and viruses exchange genetic material? DOI

Irafasha C Casmil,

Anna K. Blakney

Molecular Therapy, Journal Year: 2024, Volume and Issue: 32(8), P. 2437 - 2438

Published: July 20, 2024

Language: Английский

Citations

2
Design and development of mRNA and self-amplifying mRNA vaccine nanoformulations DOI
Yadollah Omidi, Mohammad M. Pourseif, Rais A. Ansari

et al.

Nanomedicine, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 27

Published: Nov. 13, 2024

The rapid evolution of mRNA vaccines, highlighted by Pfizer-BioNTech and Moderna's COVID-19 has transformed vaccine development therapeutic approaches. Self-amplifying (saRNA) a groundbreaking advancement in RNA-based offer promising possibilities for disease prevention treatment, including potential applications cancer neurodegenerative diseases. This review explores the complex design these innovative with focus on their nanoscale formulations that utilize nanotechnology to improve delivery effectiveness. It articulates fundamental principles saRNA mechanisms action, role synthetic eliciting immune responses. further elaborates various systems (e.g., lipid nanoparticles, polymeric nanoparticles other nanocarriers), emphasizing advantages enhancing stability cellular uptake. addresses advanced techniques such as microfluidics discusses challenges formulating vaccines. By incorporating latest technologies current research, this provides thorough overview recent nanovaccines advancements, highlighting revolutionize technology broaden clinical applications.

Language: Английский

Citations

2
Venezuelan equine encephalitis virus non-structural protein 3 dictates superinfection exclusion in mammalian cells DOI Creative Commons
Tessy A. H. Hick,

Taja Zotler,

Davita Bosveld

et al.

npj Viruses, Journal Year: 2024, Volume and Issue: 2(1)

Published: Sept. 13, 2024

Superinfection exclusion (SIE) prevents secondary infections of already infected cells. Arthritogenic alphaviruses induce SIE via early proteolytical cleavage replicase precursor by non-structural protein 2 (nsP2). Here, we explore the mechanism encephalitic Venezuelan equine encephalitis virus (VEEV). Using single-cell imaging techniques and VEEV replicons encoding green or red fluorescent proteins, observed full capacity in three hours. Transient expression nsP3, but not nsP2, reduced alphavirus replication, suggesting a key role for nsP3 mechanism. In particular, C-terminal hypervariable domain (HVD) was found to be required sufficient more distantly related Sindbis virus. As HVD is known bind multiple host proteins form RNA replication complexes modulate cellular stress response, propose that sequestering essential protein(s) interferes with superinfecting alphavirus.

Language: Английский

Citations

1