De novo designed proteins neutralize lethal snake venom toxins

Snake venom protection by a cocktail of varespladib and broadly neutralizing human antibodies

Snake envenomation is a neglected tropical disease, with 600 species causing over 100,000 deaths and 300,000 permanent disabilities in humans annually. Broadly neutralizing antibodies and broad chemical inhibitors have been proposed as solutions, but how to develop a therapeutically effective cocktail and the number of required components have been unclear. To address this gap, we iteratively recovered two broadly neutralizing antivenom antibodies from the memory B cells of a hyperimmune human donor with extensive snake venom exposure. The antibodies recognized conserved neutralizing epitopes on prevalent long and short snake neurotoxins, with crystal structures revealing antibody mimicry of the interfaces between these neurotoxins and their host target, the nicotinic acetylcholine receptor. We combined and tested these antibodies and the phospholipase inhibitor varespladib. A 3-component cocktail rescued animals from whole-venom challenge of all species in a 19-member WHO Category 1 and Category 2 elapid diversity set, with complete protection against most snakes observed.

Practical progress towards the development of recombinant antivenoms for snakebite envenoming

INTRODUCTION

Snakebite envenoming is a neglected tropical disease that affects millions globally each year. In recent years, research into the potential production of recombinant antivenoms, formulated using mixtures of highly defined anti-toxin monoclonal antibodies, has rapidly moved from a theoretical concept to demonstrations of practical feasibility.

AREAS COVERED

This article examines the significant practical advancements in transitioning recombinant antivenoms from concept to potential clinical translation. The authors have based their review on literature obtained from Google Scholar and PubMed between September and November 2024. Coverage includes the development and validation of recombinant antivenom antibody discovery strategies, the characterization of the first broadly neutralizing toxin class antibodies, and recent translational proof-of-concept experiments.

EXPERT OPINION

The transition of recombinant antivenoms from a 'concept' to the current situation where high-throughput anti-venom mAb discovery is becoming routine, accompanied by increasing evidence of their broad neutralizing capacity in vivo, has been extraordinary. It is now important to build on this momentum by expanding the discovery of broadly neutralizing mAbs to encompass as many toxin classes as possible. It is anticipated that key demonstrations of whether recombinant antivenoms can match or surpass existing conventional polyvalent antivenoms in terms of neutralizing scope and capacity will be achieved in the next few years.

Dual Proteomics Strategies to Dissect and Quantify the Components of Nine Medically Important African Snake Venoms

Snakebite envenoming constitutes a significant global health issue, particularly in Africa, where venomous species such as Echis vipers and Dendroaspis mambas pose substantial risks to human health. This study employs a standardized venomics workflow to comprehensively characterize and comparatively quantify the venom composition of nine medically relevant snake species chosen from among the deadliest in Africa. Utilizing shotgun venom proteomics and venom gland transcriptomics, we report detailed profiles of venom complexity, highlighting the relative abundance of dominant toxin families such as three-finger toxins and Kunitz-type proteins in Dendroaspis, and metalloproteinases and phospholipases A2 in Echis. We delineate here the relative abundance and structural diversity of venom components. Key to our proteomic approach is the implementation of Multi-Enzymatic Limited Digestion (MELD), which improved protein sequence coverage and enabled the identification of rare toxin families such as hyaluronidases and renin-like proteases, by multiplying the overlap of generated peptides and enhancing the characterization of both toxin and non-toxin components within the venoms. The culmination of these efforts resulted in the construction of a detailed toxin database, providing insights into the biological roles and potential therapeutic targets of venom proteins and peptides. The findings here compellingly validate the MELD technique, reinforcing its reproducibility as a valuable characterization approach applied to venomics. This research significantly advances our understanding of venom complexity in African snake species, including representatives of both Viperidae and Elapidae families. By elucidating venom composition and toxin profiles, our study paves the way for the development of targeted therapies aimed at mitigating the morbidity and mortality associated with snakebite envenoming globally.

AI/ML methodologies and the future-will they be successful in designing the next generation of new chemical entities?

Cheminformatics and chemical databases are essential to drug discovery. However, machine learning (ML) and artificial intelligence (AI) methodologies are changing the way in which chemical data is used. How will the use of chemical data change in drug discovery moving forward? How do the new ML methods in molecular property prediction, hit and lead and target identification and structure prediction differ and compare with previous computational methods? Will new ML methodologies improve chemical diversity in ligand design, and offer computational enhancements. There are still many advantages to physics based methods and they offer something lacking in ML/ AI based methods. Additionally, ML training methods often give the best results when experimental assay measurements are fed back into the model. Often modeling and experimental methods are not diametrically opposed but offer the greatest advantage when used complementary.

Targeted ubiquitination of Na V 1.8 reduces sensory neuronal excitability

Chronic pain and addiction are a significant global health challenge. Voltage-gated sodium channel Na V 1.8, a pivotal driver of pain signaling, is a clinically validated target for the development of novel, non-addictive pain therapeutics. Small molecule inhibitors against Na V 1.8 have shown promise in acute pain indications, but large clinical effect sizes have not yet been demonstrated and efficacy in chronic pain indications are lacking. An alternative strategy to target Na V 1.8 channels for analgesia is to reduce the number of channels that are present on nociceptor membranes. We generated a therapeutic heterobifunctional protein, named UbiquiNa V , that contains a Na V 1.8-selective binding module and the catalytic subunit of the NEDD4 E3 Ubiquitin ligase. We show that UbiquiNav significantly reduces channel expression in the plasma membrane and reduces Na V 1.8 currents in rodent sensory neurons. We demonstrate that UbiquiNa V is selective for Na V 1.8 over other Na V isoforms and other components of the sensory neuronal electrogenisome. We then show that UbiquiNa V normalizes the distribution of Na V 1.8 protein to distal axons, and that UbiquiNa V normalizes the neuronal hyperexcitability in in vitro models of inflammatory and chemotherapy-induced neuropathic pain. Our results serve as a blueprint for the design of therapeutics that leverage the selective ubiquitination of Na V 1.8 channels for analgesia.