Posters and presentation information
Thank you for considering presenting your work as a poster at this conference.
The deadline for digital posters and flash-talk videos submission this year is 20th August 2025.
Poster preparation and submission
- Poster size: Prepare your poster as you would normally do for printing.
> Presenting digitally only: You can save your poster in sizes A1 or A0, landscape or portrait, as the page size is not important if presenting digitally only.
> Presenting in-person: Print hardcopy posters in A1 portrait format only.
> Larger posters and those in landscape format may not be displayed due to space constraints.
- Naming your poster files: Name your poster files as follows: <your surname>-Ven25-Poster.pdf. For example, for David Jones, name your file as Jones-Ven25-Poster.pdf.
> DO NOT name your poster files as, e.g., Oxford-poster, Venoms2025, Oxford-venoms-poster. Such files will not be considered.
- Poster submission and deadlines: All poster presenters, whether attending virtually or in-person, are required to submit a digital version of their poster for viewing by both virtual and in-person attendees. The posters will be made available via the secure ‘Download VEN25 Documents’ page to all conference participants.
> Submit your final poster as a PDF (<5MB) and via the link below no later than the advertised dates.
> Late posters may not be included in the conference programme.
> DO NOT send your poster (or abstract) files by email.
> Please ensure you send us the very final version of your poster (as well as your poster abstract), as once published, it cannot be replaced.
Poster presentation
- Presentation time: There is no specific time for presenting digital posters. The participants will be able to interact with virtual presenters via the Zoom chatbox during the conference. However, we strongly recommend that the presenters submit a flash-talk video (see below) of their poster to get maximum exposure during and after the conference.
- Flash-talk videos: We are pleased to offer poster presenters the opportunity to prepare a short video presentation about their poster and send it before the conference. The videos will be made available on the LPMHealthcare YouTube channel. Below is further information for sending your video presentation.
> Download the opening slide (VenOx25 first slide) and use it as the first slide of your presentation (see example: https://youtu.be/XatqenCd_IU?si=Yu1PooCD4JmSLAiz).
> Give your presentation (no longer than 5 minutes) using Zoom or another platform of your choice.
> Convert the video into a format compatible with YouTube (e.g., MP4).
> Send your video to VenomsOxford@gmail.com using a file transfer program, such as MailBigFile or WeTransfer.
Hardcopy posters: If attending in-person, you may bring along a printed copy of your poster (maximum A1 size) to be displayed during the conference.
> Please note that you are responsible for printing your poster and only print in A1 portrait format.
> You may be assigned a specific day for displaying your poster.
Any further information about the poster presentations will be available in the future on the conference website.
Upload Your Digital Poster
Before uploading your poster, you must make sure that you follow ALL of the instructions above!
Accepted posters (unedited)
(Presenters in Bold; virtual only posters are marked V)
If your abstract has been accepted for presentation but it does not appear in the list below, please let us know as soon as possible by email at VenomsOxford@gmail.com.
Venom for health: discovery of drug template from scorpion venom for brain tumor (V)
Mehtab Alam1, Hubert Kalbacher2, Munazza Raza3, Iftikhar Haider Naqvi4, Durrey Shahwar1, Humaira Hassan3, Muhammad Khurrum Abbas1, Mateen Ahmed Siddiqui1, Rameez Ahmed Khan1, Ibrahim Ahmed Khan1
1Dr Zafar H. Zaidi Center for Proteomics, University of Karachi, Pakistan
2Interfacultary Institute for Biochemistry, University of Tuebingen, Hoppe-Seyler-Str. 4, 72076 Tuebingen, Germany
3Dr Panjwani Center for Molecular Medicine and Drug Research, ICCBS, University of Karachi
4Medicine Unit, Dow University of Health Sciences, Karachi, Pakistan
The central nervous system tumors are thirteenth most commonly diagnosed tumors in Pakistan and eighth most frequent cause of cancer related mortality. Glioblastoma is considered as one of the aggressive, deadliest and most abundant brain tumor in Pakistan. Various venomics studies revealed that venom is a cocktail of therapeutic compounds. Scorpions venom contain various bioactive peptides including antitumor peptides like Chlorotoxin which act on voltage gated chloride channel, annexin-2 and Matrix Metalloprotease-2 (MMP-2) without harming normal cells. The chlorotoxin-like peptide has been isolated and sequenced from yellow scorpion of Sindh, Pakistan. The peptide named as Bs8 is synthesized by solid phase synthesis. The tumor suppression activity and IC50 value of crude scorpion venom and synthetic peptide was determined on Glioblastoma cell lines (U87-MG) in-vitro. Mechanism of cancer cell death was evaluated by ROS measurement and RT-PCR of apoptotic genes. The synthetic peptide showed activity on brain tumor cell lines and can be further optimized to use as drug template.
Development of an electrochemical model for the detection and evaluation of the potential toxicity of naturally occurring furanic compounds
Imène AYADEN1, Chouaha BOUZIDI1, Thomas GASLONDE1, Joëlle PERARD-VIRET1, Florence SOUQUET1, Céline HOFFMANN2, Xavier CACHET1
1CiTCoM UMR CNRS 8038, Faculty of pharmacy of Paris, Paris Cité University, Paris, France
2UTCBS UMR CNRS 8258 INSERM U1267, Faculty of pharmacy of Paris, Paris Cité University, Paris, France
Nature offers both therapeutic substances and toxic threats. The rise in popularity of plant-based remedies, often perceived as safer alternatives to conventional medicine, presents regulatory challenges due to limited pharmacological and safety data. Among the poorly characterized natural compounds, furanic compounds stand out. These molecules, defined by their furan or dihydrofuran ring, are found in plants, fungi, tobacco smoke, exhaust gases, and food, particularly roasted or processed ones such as coffee and baby food. Despite being labelled as potentially carcinogenic, their mechanisms of toxicity remain underexplored. Metabolic activation by cytochrome P450 enzymes converts these compounds into highly reactive 1,4-enedial intermediates, capable of trapping nucleophiles such as DNA and proteins, triggering oxidative stress and cellular injury. Such biochemical events contribute to a range of toxic effects across multiple organs, particularly the liver and tissues exposed via inhalation or ingestion. Chronic exposure has been linked to inflammation, tissue injury, and morbidity. With rising levels of environmental furans driven by industrial emissions and global warming, there is an urgent need for predictive tools to assess their toxicological profile. Our work aims to develop a robust electrochemical model that mimics CYP450-mediated activation to screen the toxic potential of furanic compounds. We investigated the relevance of redox potential as a predictive parameter for furan toxicity, and the correlation of this electrochemical model with the measure of CYP3A4 inhibition in a cell-based in vitro model using HepaRG cells. By simulating enzyme-like conditions, the electrochemical model could perform as a fast, mechanistic, and predictive tool for assessing the risks associated with exposure to both naturally occurring and other environmental furans, finally enabling more systematic safety assessments.
Recombinant expression of the disintegrin-like domain of type III metalloprotease from Bothrops pictus venom (V)
Tania A Broncano-Gutierrez, Jorge A Roque Arévalo, Daniel A Torrejón, Fanny Lazo, Armando Yarlequé, Dan E Vivas-Ruiz
1Grupo de Investigación de Toxinas de Origen Animal y sus Antivenenos (TOXIVEN) – Laboratorio de Biología Molecular, Facultad de Ciencias Biológicas, Universidad Nacional Mayor de San Marcos, Lima, Perú
Snake envenomation is a public health problem in Peru, with Bothrops pictus responsible for most incidents in the coastal region. Its venom contains disintegrin-like proteins with therapeutic potential, yet they remain poorly studied. In this work, the sequence corresponding to a disintegrin-like domain was designed and codon-optimized for Escherichia coli, incorporating an enterokinase cleavage site to facilitate downstream purification. The sequence was synthesized, cloned into the pET101/D-TOPO® vector, and transformed into ampicillin-resistant E. coli TOP10. Positive colonies were confirmed by plasmid DNA analysis through electrophoresis and spectrophotometric quantification. Purified plasmids were then transformed into E. coli BL21 Star (DE3), and recombinant protein expression was induced with IPTG for 5 hours, collecting samples at different time points for DNase treatment and further analysis. Plasmid quantification yielded concentrations between 51 and 73.7 ng/µL, with A260/A280 ratios of 1.86–1.88. SDS–PAGE revealed an increasing band at ~13 kDa, consistent with the expected size of the recombinant disintegrin-like domain plus additional purification sequences. These results provide the basis for future purification and functional characterization. Financial support: CONTRATO N.º PE501088550-2024-PROCIENCIA.
Directional expression of the rC domain of an SVMP-III from Bothrops pictus in E. coli: soluble Trx–6×His fusion with immunological recognition (V)
Juan Jose Cabrejos, Daniel A Torrejon, Jorge A Roque, Tania A Broncano, Dan Vivas-Ruiz, Armando Yarlequé
Animal Toxins and Antivenoms Research Group (TOXIVEN) – Molecular Biology Laboratory, Faculty of Biological Sciences, Universidad Nacional Mayor de San Marcos, Lima, Perú
Recombinant expression of the cysteine-rich domain (rC) of a snake venom metalloproteinase type III (SVMP-III) from Bothrops pictus in Escherichia coli was achieved using the pET102/D-TOPO system. The rC gene was amplified with a directional CACC overhang primer and without a stop codon to allow in-frame fusion to the vector-encoded HP-thioredoxin and C-terminal 6×His tag. The TOPO cloning mixture was transformed into E. coli TOP10; colony PCR yielded single amplicons of ~1.0–1.1 kb, consistent with the expected size (~1035 bp) versus the no-insert control (~0.65 kb). Minipreparations showed plasmids of ~6.7 kb relative to the ~6.3 kb empty vector. Plasmid sequencing (Oxford Nanopore MinION) confirmed correct insert orientation and maintenance of the reading frame across the fusion junction. For production, the validated construct was transformed into E. coli BL21 Star (DE3) and induced with IPTG, with leakiness modulated by glucose. Non-reducing SDS–PAGE revealed a dominant band at ~26–27 kDa that increased between 2–4 h and was sustained at 4 h, matching the theoretical mass of the Trx–rC fusion; at 0 h with glucose the signal was minimal, whereas in the absence of glucose a slight basal expression was observed, consistent with catabolite repression effects. Antigenicity of the recombinant product was verified by indirect ELISA using a polyclonal antibody, yielding a specific signal against the antigen. Collectively, these data demonstrate the production in E. coli of a soluble, correctly oriented SVMP rC that retains antibody recognition, providing an accessible platform for structural and functional studies with high biomedical potential as an antigen for immunogen development, diagnostics, and antivenom strategies. The antibody specifically recognized the recombinant protein (~26 kDa) and multiple proteins from B. pictus crude venom. This work was funded by PROCIENCIA (contract PE501088550-2024), VRIP (code B25100061) and FONDECYT (code 1241547).
Platelet activation induced by Bothrops moojeni venom: from Calcium signaling to mitochondrial function
Nathalia Carvalho1,2, Ella Ykema2, Nicola Dark2, Paul C Armstrong2, Timothy D Warner2, Lucia H Faccioli1, Harriet Allan2
1Department of Clinical Analysis, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
2Queen Mary University of London – The Blizard Institute of Cell and Molecular Science, London, UK
Bothrops moojeni venom disrupts hemostasis by activating platelets, yet its mechanisms remain unclear. We investigated platelet responses to B. moojeni venom focusing on aggregation, activation markers, calcium signaling, and mitochondrial function. Washed platelets supplemented with fibrinogen were exposed to venom (0.1–10 μg/mL), collagen, or thrombin-receptor activating peptide (TRAP-6). Platelet aggregation increased dose-dependently with venom, reaching 63% at 1 μg/mL and 84% at 10 μg/mL, comparable to collagen and exceeding TRAP-6 responses. Pre-treatment of platelets with a P2Y12 receptor antagonist, prostaglandin E1 (PGE1), and eptifibatide reduced venom-induced aggregation by 34%, 26%, and 22%, respectively, while aspirin had no effect. Flow cytometry revealed that venom enhanced α- and dense-granule release, shown by increased CD62P and CD63 expression at levels similar to collagen and TRAP-6, but did not alter PAC-1 or Annexin V binding. Interestingly, P2Y12 antagonist and PGE1 reduced these activation markers, whereas eptifibatide did not, despite lowering aggregation. Venom induced a sustained rise in intracellular calcium, peaking shortly after stimulation and remaining elevated over time, similar to stimulation with collagen related peptide (CRP-A), while TRAP-6 caused a faster but transient increase. Mitochondrial membrane potential decreased progressively following venom and TRAP-6 exposure, indicating depolarization; CRP-A induced milder effects. These findings suggest B. moojeni venom activates platelets via P2Y12, adenylate cyclase, and GPIIb/IIIa pathways, triggering granule secretion alongside sustained calcium signaling and mitochondrial dysfunction. This deepens understanding of venom-induced platelet dysfunction and may guide therapeutic approaches for snakebite-related coagulopathy.
Epidemiological overview of scorpion accidents in the state of Goiás, Central Brazil
Isadora M L R de Castro1, Layane B F Pinto1, Isabela C Aragão1, Ivone F Souza2, Nelson J S Júnior1, Juliany G G Silva1,2
1Pontifical Catholic University of Goiás, School of Medical and Life Sciences, Graduate Program in Environmental and Health Sciences, Goiânia, Goiás, Brazil
2Pontifical Catholic University of Goiás, School of Social and Health Sciences, Graduate Program in Environmental and Health Sciences, Goiânia, Goiás, Brazil
Scorpion stings represent a growing public health challenge in Brazil, with the state of Goias standing out due to its high and increasing incidence. This study aimed to characterize the epidemiological profile of scorpion accidents in Goias from 2003 to 2018 by analyzing 28,984 records from the notification database of the Tropical Diseases Hospital of Goiania-GO. After screening and analyzing the data, 10,552 confirmed cases of scorpion stings were identified. Most accidents occurred in urban areas (68.36%), with a predominance among males (52.1%). Adults aged from 20 to 29 years old were the most affected (18.47%) by it, but all ages groups were represented. Accidents were evenly distributed throughout the year, with a slight increase in the month of April. The upper limbs, especially arms, hands, and fingers (46.28%), were the most affected body regions. Most patients (77.7%) received medical care within 3 hours, which contributed to the predominance of mild clinical presentations (78.18%), while moderate and severe cases accounted for 15.16% and 4.1%, respectively. Local pain was the main symptom, while systemic manifestations were less frequent. Serum therapy was administered in 33.7% of cases, mainly in moderate and severe cases. Complications and deaths were rare, and the overall prognosis were favorable to most patients achieving complete recovery (86.3%). The results highlight the shift of scorpionism towards urban settings and the importance of fast access to care, reinforcing the need of surveillance and prevention, specifically in urban areas and through health education. Funding: CNPq fellowships (NJS Jr: 315058/2023-4).
Galleria Envenoming Model (G.E.M.): an alternative in vivo non-mammalian model using Galleria mellonella (wax moth) larvae
Rachel Bridge1, James Pearce2, Aarón Gómez3, Stuart Ainsworth4, Guillermo León Montero3, James Wakefield2, Stefanie K Menzies5 and Rachel H Clare1
1Biology Department, Edge Hill University, St Helens Road, Ormskirk, UK, L39 4QP
2Living Systems Institute/Department of Biosciences, University of Exeter, Stocker Road, Exeter, UK, EX4 4QD
3Instituto Clodomiro Picado, Universidad de Costa Rica, Dulce Nombre of Coronado, San José, Costa Rica
4Institute of Infection, Veterinary & Ecological Sciences, University of Liverpool, Brownlow Hill, Liverpool, UK,
L69 7ZX
5Biomedical & Life Sciences, Lancaster University, Bailrigg, Lancaster, UK, LA1 4YW
Snakebite envenoming (SBE) annually kills ~100,000 people worldwide, with 4-fold more suffering life-altering morbidity. Antivenom, the only approved treatment, requires preclinical models to assess efficacy and safety as an essential part of the regulated manufacturing process. The only validated assays to determine the potential clinical effectiveness of an antivenom are preclinical rodent models (typically mice). These procedures are rated ‘severe’ in the UK and EU, are resource-intensive and require high animal numbers. Galleria mellonella (herein referred to as Galleria) have gained momentum as a replacement for vertebrate models in the last decade across many biological fields. Developing a Galleria model for SBE would provide a low-cost, resource-light, high-throughput non-vertebrate alternative model. Our pilot data demonstrates that Galleria envenoming pathology is comparable to mammalian envenoming – i.e. coagulopathic venoms impair the clotting function of both mammalian blood and Galleria hemolymph, and neurotoxic venoms cause rapid paralysis in mammals and Galleria. Through our NC3Rs-funded project titled Galleria Envenoming Model (G.E.M) we will, i) develop the model to allow for quantitative non-biased analysis of clotting, paralysis and cytotoxicity, ii) validate this model through determining the LD50 of 14 diverse venoms (inclusive of Elapids and Vipers) and the ED50 of three antivenoms (including correlation to the associated mouse data), before iii) establishing the model in two academic groups and one antivenom manufacturer to demonstrate replicability. In parallel, we will host workshops to train additional laboratories to establish the same standardised model.
Development of an Analytical Framework to Evaluate Antivenom Efficacy through Magnetic Beads and BioLayer Interferometry
Thomas Crasset1, Germain Besonhé1, Damien Redureau1, Fernanda Gobbi Amorim1, Nicholas R Casewell2, Stefanie K Menzies3, Christiane Berger-Schaffitzel4, Marylène Vandevenne5, Loïc Quinton1
1Laboratory of Mass Spectrometry, MolSys Research Unit, University of Liège, 4000 Liège, Belgium
2Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
3Department of Biomedical and Life Sciences, Lancaster University, Lancaster LA1 4YG, UK
4School of Biochemistry, University of Bristol, 1 Tankard’s Close, Bristol BS8 1TD, UK
5Laboratory of Enzymology and Protein Folding, Centre for Protein Engineering, InBioS, University of Liège, Liège, Belgium
Snake envenomation remains a critical yet neglected public health issue across Africa, the Middle East, Asia, and subtropical regions, affecting mostly rural populations. Despite the availability of antivenoms, their limitations, such as poor thermal stability, risk of adverse reactions, and ethical-concerned production relying on hyperimmunized animals, underscore the urgent need for innovative therapeutic approaches. The European ADDovenom project (2021–2025, FET-Open H2020) addresses these challenges by developing a new generation of antivenoms based on ADDomers: virus-like particles that are thermally stable, cost-effective, and capable of displaying 60 high-affinity binding sites. A major bottleneck in antivenom development and quality control lies in the limited information on the specific venom toxins targeted by antivenom antibodies. To overcome this, we present integrated, automatable workflows for captured toxin identification, quantification, and affinity assessment. Using tosylactivated or Protein G magnetic beads coupled to EchiTab G, a monospecific antivenom prepared to neutralize Echis ocellatus toxins, we probed its cross-reactivity with Echis romani. Toxins captured and uncaptured were analyzed via LC-MS/MS following tryptic digestion, enabling detailed mapping of the antivenom’s immunorecognition profile. Additionally, biolayer interferometry (BLI) was employed to determine the apparent dissociation constants of whole antivenoms against crude venoms, facilitating direct comparison with emerging alternatives like nanobodies, monoclonal antibodies, and Addobody constructs. These streamlined methods require minimal sample quantities, are fully automatable, and hold strong potential for routine application in antivenom quality control—paving the way toward more rational, targeted, and effective snakebite therapies.
When comorbidity and traditional practices complicates envenomation: A fatal case in hypertensive and goitrous patient following snakebite in rural Cameroon (V)
Tatiana K Djikeussi1,8, Francis Noumen2, Awelsa Benoit 3, Rogacien Kana1, Jinette L Guedem1, Malama Toussaint3, Ngu Hilmann4, Louabalbe P. Emmanuel 4, Issaka Sali5, Yaouba Daouda5, Armelle Messa6, Maraimou I issa6, Arthur Djoumessi2, Nathalie Elombo2, Gavli Dongoa7, Gilbert Keblouabe7, Vishwas Sovani8, Deepak Langade8, Millind V Khadilkar8
1Health for Africa Now, Douala, Cameroon
22N pharmaceutique, Douala, Cameroon
3District hospital Mayo Oulo, North Cameroon
4District hospital Poli, North Cameroon
5Regional Hospital Garoua, North Cameroon
6District hospital Gashiga, North Cameroon
7Regional Delegation of Public health, North Cameroon
8Premium Serums & Vaccines Pvt.Ltd. (PSVPL), India
Snakebite envenomation (SBE) remains a critical but under-addressed public health issue in rural sub-Saharan Africa, where limited healthcare infrastructure, reliance on traditional remedies, and chronic disease burdens converge to shape clinical outcomes. In northern Cameroon, where vipers such as Echis spp. are prevalent, timely access to antivenom, and supportive care is often impeded by financial and cultural barriers. We report the case of a 60-year-old female farmer from Mayo-Oulo with longstanding goiter and untreated hypertension, who presented with a complex evolution of symptoms following a viper bite to the lower limb. Initial management involved traditional herbal remedies. She presented to the hospital three hours post-bite with grade 1 cytotoxicity, BP 173/114 mmHg, GCS 15, coagulable blood, and Hb 12.4 g/dL. One dose of polyvalent antivenom was administered. Within two hours, symptoms progressed to grade 2 cytotoxicity, epigastric pain, and emerging hematotoxicity, prompting a second dose. On day three, delayed muscarinic symptoms developed (sweating, lacrimation, hypersalivation, dysphagia, dysphonia, bradypnea, nausea), managed with atropine, though malignant hypertension persisted. This raised suspicion of curare-like toxicity from traditional compounds or venom-induced autonomic dysfunction exacerbated by endocrine comorbidity. Despite medical advice for multidisciplinary referral, the patient declined due to financial constraints and returned to traditional care. She died seven days later in the community. This case underscores the fatal intersection of envenomation, unmanaged endocrine disease, and traditional plant-based practices. It calls for integrated protocols that address comorbidities, promote early antivenom access, provide financial protection, and incorporate culturally sensitive education into rural SBE management.
Reversing Renal Crisis: Snakebite-Induced AKI Successfully Managed with Dialysis and Polyvalent Antivenom in Cameroon (V)
Tatiana K Djikeussi1,7, Rogacien Kana1, Jinette L Guedem1, Issaka Issa2, Yaouba Daoauda 2, Awelsa Benoit3, Malama Toussaint3, Louabalbe P Emmanuel 4, Ngu Hilmann4, Armelle Messa5 Maraimou I Issa5, Arthur Djoumessi6, Nathalie Elombo6, Vishwas Sovani7, Deepak Langade7, Milind V Khadilkar7, Francis Noumen6
1Health for Africa Now, Douala Cameroon
2Regional Hospital Garoua, North Cameroon
3District hospital Mayo Oulo, North Cameroon
4District hospital Poli, North Cameroon
5District hospital Gashiga, North Cameroon
62N pharmaceutique, Douala Cameroon
7Premium Serums & Vaccines Pvt Ltd (PSVPL), India
Acute kidney injury (AKI) secondary to hematotoxic snakebite remains underrecognized and under documented, especially in sub-Saharan Africa. We report the case of a 39-year-old woman bitten on the left foot by a West African carpet viper (Echis ocellatus) while farming in Northern Cameroon. She received six doses of antivenom and three units of blood at Poli district referring center before being transferred to Garoua Regional Hospital, eight days post-bite. At admission, she presented with hematemesis, tumefaction, hematuria, anuria, vomiting, and signs of volume overload. Despite being fully conscious, she was hemodynamically unstable (HR 93 bpm, BP 144/79 mmHg, Temp 36.6 °C), with pronounced pallor and leg swelling. Laboratory evaluation revealed leucocytosis, anaemia (Hb 7.3 g/dL), thrombocytopenia, and severe renal impairment (urea: 4.8 g/L; creatinine: 198 mg/L). Urinalysis showed proteinuria and ascorbic acid traces. Coagulation tests were abnormal. She was managed with four additional doses of PANAF-Premium polyvalent antivenom, four units of blood, and 12 haemodialysis sessions. Renal function and urine output progressively improved, allowing discharge on October 18. Follow-up on November 1 revealed fever, vomiting, and epigastric pain; she was treated for severe malaria and hyperalgesic gastritis. She has since resumed normal activities. This case demonstrates that even delayed AKI secondary to envenomation can be successfully reversed through sustained dialysis, prompt antivenom use, and supportive care. The absence of adverse events underlines the favorable safety profile of PANAF-Premium. Continued availability of free antivenom and renal support services is essential to improving outcomes in high-risk, rural settings.
Snake venom CdtVEGF and its ability to bind to VEGF receptors
Isabela G Ferreira1,2,3, Anton Smith3, David O Bates3, Andrew V Benest2, Eliane C Arantes1
1School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
2Endothelial Quiescence Group, Centre for Cancer Sciences, Biodiscovery Institute, School of Medicine, University of Nottingham, Nottingham, UK
3Tumour and Vascular Biologies Laboratory, Biodiscovery Institute, School of Medicine, University Nottingham, Nottingham, UK
Snake venoms are rich in bioactive components, particularly proteins with significant pharmacological effects. However, isolating native proteins can yield very low recovery rates. For example, in rattlesnake venom (Crotalus durissus terrificus, Cdt), a homodimeric vascular endothelial growth factor (VEGF) with molecular mass of 25 kDa was recovered as 2% of the total venom. Since VEGFs have the ability to promote angiogenesis and increase vascular permeability through direct interaction with VEGF receptors (VEGFRs), in this study we analysed native CdtVEGF, isolated from Cdt venom and PEG-CdtVEGF regarding their capacity to bind to VEGFRs (R2 and R1). KDR NFAT-RE HEK293 cells were transfected with plasmid containing VEGFR1 DNA and following the transfection, cells were treated with 100 ng/mL of VEGFA165, VEGFA165b, CdtVEGF, PEG-CdtVEGF and the mixture of VEGFA165 + VEGFA165b, CdtVEGF + VEGFA165b and PEG-CdtVEGF + VEGFA165 (1nM each), incubated for 6 hours and Bio-Glo Luciferase reagent was added to analyse the bioluminescence. Our results demonstrate that CdtVEGF is a weak agonist for the R2, and when mixed together with VEGFA165b (also a weak agonist) on transfected cells with R1 they presented a binding capacity for the R1. PEG-CdtVEGF when tested with R2, low binding capacity was evaluated, however, when mixed together with VEGFA165, could bind to R1 and R2. We could hypothesize that PEG-CdtVEGF although not so active on its own, it appears to function as a positive allosteric modulator or co-ligand, enhancing or stabilizing the agonist VEGFA165 interaction with the receptor. Additionally, our findings present enlightening results about the ability of svVEGFs to bind to VEGFRs, triggering endothelial cells migration, proliferation, increased vascular permeability and new vessel formation.
Identification of potential anticancer peptides from animal venoms using mass spectrometry techniques
Lou Freuville1,2, Alisson Kabili2, Inès Dallenogare2, Chloé Matthys, Alain Brans3, Jean-Pierre Gillet2, Loïc Quinton1
1Mass Spectrometry Laboratory, MolSys Research Unit, Department of Chemistry, University of Liège, Allée du Six Août, 11 – Quartier Agora, 4000, Liège, Belgium
2Laboratory of Molecular Cancer Biology, URPhyM, NARILIS, Faculty of Medicine, University of Namur, rue de Bruxelles, 51, 5000, Namur, Belgium
3Centre for Protein Engineering, University of Liège, University of Liège, Allée du Six Août, 11 – Quartier Agora, 4000, Liège, Belgium
Esophageal adenocarcinoma (EAC) remains one of the most lethal cancers, with a 5-year survival rate under 20 %. The main causes are late diagnosis and limited treatment options, due to the development of some cancer resistance mechanisms. In search of novel therapeutic avenues, this project explores the untapped pharmacological potential of animal venoms, with a focus on peptide toxins that exhibit selective cytotoxicity against EAC cells. Animal venoms are complex mixtures composed of peptides and proteins, selected by millions of years of evolution to act against molecular targets, such as G-protein coupled receptors (GPCRs) and ion channels. There are around 220,000 venomous species, and according to transcriptomic and proteomic studies, animal venoms are composed of a few hundred proteins and peptides. Venoms can therefore be seen as a molecular toolbox composed of tens of millions of bioactive peptides and proteins, where less than 0.1% has been characterized to date. The experimental procedure starts with venom fractionation, followed by a biological test on three EAC cell lines exhibiting various degrees of resistance to treatments, and a normal esophageal cell line. Fractions with selective cytotoxic activity against cancer cells were analyzed using mass spectrometry to identify and characterize peptide toxins causing cell death. Efforts are now focused on identifying their mechanisms of action and their target using HA-tagged peptides, pull-down assay, and mass spectrometry. Furthermore, a transcriptomic analysis of approximately 400 clinical samples identified ion channels and other membrane receptors differentially expressed among drug-resistant and -sensitive clinical samples. They may represent potential targets for venom peptides and serve as biomarkers for precision medicine.
Tracing the neutralization path: kinetics of antivenom activity in the lymphatic system following intramuscular and intravenous administration
Erika Gamulin1, Sanja Mateljak Lukačević1, Maja Lang Balija1, Ana Smajlović2, Dražen Vnuk2, Beata Halassy1 and Tihana Kurtović1
1Centre for Research and Knowledge Transfer in Biotechnology, University of Zagreb, Rockefellerova 10, 10000 Zagreb, Croatia
2Clinic for Surgery, Orthopaedics and Ophthalmology, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10000 Zagreb, Croatia
In viper envenomation, the venom is typically injected into the subcutaneous or muscle tissue and is primarily absorbed through the lymphatic system before reaching the systemic circulation. Although antivenoms are central to snakebite treatment, most research has focused on their pharmacokinetics in the blood, leaving the role of the lymphatic system poorly investigated. Yet, this is where venom initially accumulates, suggesting that the lymph may be a critical space for early neutralization. The study aimed to improve our understanding of how antivenom behaves in the lymphatic system and to establish whether the route of administration, intravenous (i.v.) or intramuscular (i.m.), affects its ability to reach and neutralize venom at this early stage. We used sheep as a large animal model to simulate the human envenomation dynamics. A venom dose corresponding to a dose injected in the typical envenomation was applied subcutaneously (s.c.), followed by the antivenom administration either via an i.v. infusion or an i.m. injection. Lymph was continuously collected from the thoracic duct, and blood samples were taken at defined time points. Venom and antivenom concentrations were quantified using in-house ELISA assays. Our focus was on how quickly the antivenom reached the lymph, its peak levels, and the relationship with the decline of the venom in the same compartment. The findings reveal that the lymphatic system is not just a passive transport route, but also a key site of action. The appearance of antivenom in lymph varies depending on the administration route, and these differences can influence the effectiveness with which venom is neutralized before entering the bloodstream. Understanding this dynamic could help to refine treatment protocols and improve outcomes for snakebite patients, especially in settings where rapid intervention is critical.
Discovery of broadly neutralizing recombinant nanobodies for treatment of snakebite envenoming
Elpida Lytra, Melisa Benard-Valle, Alfredo Mena Samano, Shirin Ahmadi, Tom Jansen, Tasja Wainani Ebersole, Camilla Holst Dahl, Esperanza Rivera-de-Torre, Anne Ljungars, Andreas H Laustsen
Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
Snakebite envenoming remains a major global health issue, causing over 100,000 deaths each year and leaving many survivors with long‑term disabilities. The current therapeutic plasma‑derived methods may save plenty of lives but suffer from variable efficacy, risk of adverse reactions, batch‑to‑batch inconsistency and high costs. To overcome these problems, we are developing a simple antivenom based on recombinant single‑domain antibodies (VHHs). By combining a small mix of VHHs that neutralize key toxins from several venomous species, we aim to create a more broadly applicable and consistent treatment. In this poster, I will explain how we discover cross-reactive and high-affinity VHHs that neutralize the major viper toxins from sub‑Saharan Africa. We first purify four toxin families, — phospholipase A₂s (PLA₂s), disintegrins, snake‐venom metalloproteinases (SVMPs), and snake‐venom serine proteinases (SVSPs), —and then use phage display technology to select VHHs with strong, cross‑reactive binding. Finally, I will discuss the results from in vitro assays that identify the top VHH candidates.
First Investigation into IEC Snake Venom Toxic Fractions and Their Hematological Impact: Implications for Antivenom Development and Clinical Management (V)
Nafiseh Nasri Nasrabadi1, Hossein Vatanpour2, Mehdi Kheirollahpour3
1Control of therapeutic antivenom serums, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization, Karaj, Iran
2Department of Toxicology & Pharmacology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
3Department of human vaccine and serum, Razi Vaccine and Serum Research Institute (RVSRI), Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
Snake venom that affects the blood contain multitude proteins, including enzymes with diverse enzymatic potential to interfere on haemostatic and thrombosis mechanism when bites human. This study was carry out to investigate the biological effects of Echis carinatus (IEC) venom and its fractions on human body in Iran. This mixture has components with either synergistic or antagonistic effects on blood coagulation. Snake venoms far than some therapeutic effects, can be studied for the presence of endogenous antivenins that protect against their own toxins. In fact, without antivenin treatment, biological disturbances following snake envenomation in human quickly worsen and cause death. In-vitro and in-vivo coagulant assays were conducted to determine the effects of IEC venom and its fractions as well as the effectiveness of the polyvalent antivenin in neutralizing haematological manifestations. The results of the PT, APTT, TCT, FCT, haemorrhagic, defibrinogenating, platelet aggregation tests, and plasma hematologic parameters revealed the multifunctional features of toxins which can act on their multiple protein targets of prey. In this study, It is shown that EC bites can create severe haematological disorders within the first hours after envenoming, which require medical attention as soon as possible to reduce the severity of clinical symptoms. Further, numbers of purified fractions are more toxic than the crude venom. Eventually, in this study it is shown that polyvalent antivenin from Razi institute in Iran could led to neutralize the IEC venom biological and haematological effects.
Psychosocial risks of accidents with venomous animals in the State of Goiás, Brazil: a 16-year retrospective analysis
Layane B F Pinto¹, Isadora M L R de Castro1,2, Isabela C Aragão1, Nelson J Silva Jr1, Juliany G G Silva1,2
1Pontifical Catholic University of Goiás, School of Medical and Life Sciences, Graduate Program in Environmental and Health Sciences, Goiânia, Goiás, Brazil
2Pontifical Catholic University of Goiás, School of Social and Health Sciences, Graduate Program in Environmental and Health Sciences, Goiânia, Goiás, Brazil
Accidents involving venomous animals represent a significant public health challenge in Brazil, with a particularly high incidence in the state of Goiás, with a high combination of agricultural activities and urban expansion. This study aimed to characterize the epidemiological profile of these accidents between 2003 and 2018, based on 28,984 medical records from the Hospital de Doenças Tropicais (HDT) in Goiânia, Goiás, Brazil. The data indicated that most victims were male (62.2%), aged between 20 and 40 years (87.4%). Urban areas accounted for 40.1% of cases, rural areas for 33.4%, 25.5% were not reported, and peri-urban areas accounted for 0.25%. The highest number of accidents occurred in April (11.7%), March (11.3%) and February (11.2%), coinciding with the rainy season. The main animals involved were snakes (40.3%) and scorpions (36.4%), and of these, 26.7% had their species identified, with 23.4% related to Bothrops moojeni and 20.9% to Tityus serrulatus. Most patients (69.8%) received medical care within one to three hours after the incident, and 62% of cases were classified as mild. Bites and stings primarily affected the lower (32.6%) and upper (30.0%) limbs. Antivenom administration was recorded in 51% of cases, including Bothrops antivenom (25.5%), and anti-arachnid and anti-scorpion antivenom (12%). The large amount of antivenom administered is noteworthy, with some exceeding 20 ampoules/case. Local symptoms were common (63.2%), while systemic complications and fatalities were rare (0.2%). Complete recovery was documented in 55.7% of cases, although incomplete records limited a more comprehensive assessment of clinical outcomes. Accident prevention strategies are needed in both urban and rural areas, as well as multidisciplinary training in healthcare to reduce unnecessary interventions. The case series of accidents is strongly associated with the process of loss of natural areas and urbanization. Funding: CNPq (Process: 315058/2023-4) and FAPEG.
Snake Venom Serine Protease Homologue as a Template for Novel Anticoagulant Peptides
Kity Požek1,2, Adrijana Leonardi1, Gregor Bajc3, Matej Butala3, Anže Meden4, Stanislav Gobec4, Aljaž Pirnat5, Alenka Trampuš Bakija5, Igor Križaj1
1Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
2Faculty of Medicine, University of Ljubljana, Korytkova ulica 2, SI-1000 Ljubljana, Slovenia
3Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia
4Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, SI-1000 Ljubljana, Slovenia
5Division of Pediatrics, University Medical Centre Ljubljana, Bohoričeva ulica 20, SI-1000 Ljubljana, Slovenia
In the venom of the nose-horned viper (Vipera ammodytes ammodytes) we have identified an anticoagulant serine protease homologue (VaaSPH-1) that acts as a specific inhibitor of the intrinsic pathway of blood coagulation. It is a 34 kDa, catalytically inactive glycoprotein that acts by competitively binding to the A2 domain of activated factor VIII (FVIIIa), thereby preventing its interaction with activated factor IX (FIXa) and blocking the formation of the intrinsic tenase complex, a crucial step in this coagulation pathway. As such, it offers a promising strategy for the safer treatment of venous thromboembolism (VTE), which is a major cause of mortality and long-term disability in the developed world. VTE is characterised by the formation of blood clots in the venous system, induced by a malfunction of the intrinsic blood coagulation pathway, leading to complications such as deep vein thrombosis and pulmonary embolism. Although current anticoagulant therapies are effective, their non-selective action leads to a high risk of bleeding that requires precise dose monitoring. Due to its specificity for the intrinsic blood coagulation pathway, VaaSPH-1 offers the potential to prevent VTE and, at the same time, maintain the ability of blood clotting if required. However, the clinical application of VaaSPH-1 is limited by its large molecular size and immunogenicity. To overcome these obstacles, we are developing small peptide-based inhibitors using VaaSPH-1 as a structural template. We will present recent progress in the rational design of these novel anticoagulants for the safer therapy of VTE.
Effect of prior venom extraction on the transcriptomic profile of Bothrops atrox venom glands (V)
Alex Proleon1, Angie Regalado1, Edith Rodriguez1, Felix Urra2, Armando Yarlqué1, Dan Vivas-Ruiz1
1Laboratorio de Biología Molecular, Facultad de Ciencias Biológicas, Universidad Nacional Mayor de San Marcos, Av. Venezuela Cdra 34 S/N, Ciudad Universitaria, Lima 01, Peru.
2Laboratorio de Plasticidad Metabólica y Bioenergética, Programa de Farmacología Clínica y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
Snake venom glands are specialized organs that synthesize complex mixtures of bioactive molecules. Bothrops atrox, a medically important South American snake, produces venom rich in toxins with biomedical potential. We compared transcriptomes of venom glands from two captive specimens: one euthanized one day after venom extraction and another without prior extraction. Left and right glands were preserved in RNAlater and processed for RNA extraction with TRIzol; samples were sequenced (DNBSEQ-G400, 100 bp paired-end) and quality-filtered (Phred ≥Q30). Mapping to the B. atrox reference transcriptome (GEDR00000000.1) revealed in non-extracted glands predominance of SVMP-III (snake venom metalloproteinases type 3), followed by C-type lectins (CTLs) and bradykinin-potentiating peptides (BPPs), while in extracted glands CTLs predominated, followed by SVMP-III, PLA₂s (phospholipases A2) and SVSPs (snake venom serinoproteases); grouping all SVMP isoforms, this family dominated in both conditions. Trinity assemblies (k=25) yielded average contigs of 600–700 bp, with BUSCO completeness higher in extracted (60–70%) versus non-extracted (40–50%) glands. Most transcripts were 200–300 bp, with a greater proportion (~40%) in extracted glands. This total RNA-seq approach, without poly-A selection, detected transcripts less frequently reported in Bothrops venoms, such as higher proportions of CTLs and BPPs. While venom extraction is often used to increase toxin gene expression, our results show SVMPs are highly transcribed without stimulation, unlike SVSPs and PLA₂s, whose transcription was markedly reduced. Financial support: PROCIENCIA-CONCYTEC (PE501084299-2023; PE501093029-2024) and FONDECYT #1241547.
Hemodynamic and histological effects of Micrurus spixii coralsnake venom in rats
Júlia S Ramos1,2, Thayná CS Macedo1,2, Laura A Takabayashi1,3, Ana CQ Moura², Hidelberto M Silva4, Nelson J Silva-Jr², Stephen Hyslop¹
1Departamento de Farmacologia, FCM-UNICAMP, Campinas, SP, Brazil
2PPG em Ciências Ambientais e Saúde, PUC-Goiás, Goiânia, GO, Brazil
³Centro Universitário de Mineiros, Campus Trindade, GO, Brazil
4Núcleo de Pesquisa-FM, Universidade de Rio Verde, Campus Aparecida de Goiânia, GO, Brazil
Introduction: Coralsnake (Micrurus spp.) venoms can cause cardiovascular alterations. The Amazonian species Micrurus spixii blocks neuromuscular transmission via α-neurotoxins (3FTx) and PLA₂ enzymes, but its cardiovascular effects remain unclear. Here, we examined the hemodynamic and histological effects of M. spixii (Amazonian coralsnake) venom in rats. Methods: Anesthetized (1.5-2% isoflurane) male Wistar rats cannulated for hemodynamic monitoring were injected with venom (1 and 3 mg/kg, i.v.) alone or with L-NAME (20 mg/kg), atropine (2 mg/kg), 4-aminopyridine (4-AP; 3.5 mg/kg), tetraethylammonium (TEA; 20 mg/kg) or varespladib (VP; 1 mg/kg) i.v. 15-20 min before venom (1 mg/kg); organs were collected for histology. Data (mean±SD) were analyzed with one-way ANOVA and the Tukey test (significance: p<0.05). Ethical approval: CEUA/UNICAMP Protocol 6260-1/2023. Results: Venom doses of 1 and 3 mg/kg caused death in 15±2 min and 11±1 min, respectively (n=5), that involved biphasic hypotension, bradycardia, arrhythmias, and bradypnea. Heart, lungs, and kidneys showed edema, hyperemia, and hemorrhage, but no necrosis. L-NAME and atropine abolished the transient recovery and slightly shortened survival (11.6±3.5 and 8.6±1.5 min, respectively), but 4-AP did not affect survival (15.0±1.5 min) (n=5 each). TEA attenuated (n=3) and VP completely prevented (n=5) the hypotension; all rats survived for at least 1 h. Conclusion: M. spixii venom causes lethal hypotension mediated by PLA₂ and K+ channels. Funding: CNPq fellowships (NJS Jr: 315058/2023-4; SH: 312901/2022-4) and INCT-INOVATox (CNPq 406816/2022-0).
Docking analysis between Lys49-PLA2 from Bothrops atrox “BaMtx” and molecular targets in triple-negative breast cancer (V)
Angie Regalado1, Alex Proleon1, Fanny Lazo1, Vidalina Heredia1, Nadia Vera1, Felix Urra2, Dan Vivas-Ruiz1, Armando Yarlequé1
1Laboratory of Molecular Biology, Faculty of Biological Sciences, Universidad Nacional Mayor de San Marcos, Peru. Av. Venezuela Cdra 34 S/N, Ciudad Universitaria, Lima 01, Peru
2Laboratory of Metabolic Plasticity and Bioenergetics, Institute of Biomedical Sciences (ICBM), Faculty of Medicine, University of Chile. Av. Independencia 1027, Santiago, Chile
Snake venoms are complex toxin mixtures with biomedical potential, including antitumor effects. Among these, phospholipases A₂ (PLA₂s) are notable; Lys49-PLA₂s lack enzymatic activity but display enhanced cytotoxicity. BaMtx, a Lys49-PLA₂ from Bothrops atrox, exhibits antitumor, migrastatic, and mitochondrial metabolism–impairing activities. Its migrastatic effects may involve integrins α5β1, αVβ3, and αVβ6, while mitochondrial effects could be linked to nucleolin (NCL), all overexpressed in triple-negative breast cancer (TNBC). Using AlphaFold3 and ClusPro 2.0, BaMtx interactions with NCL and integrins were predicted. BaMtx typically forms dimers; binding of two palmitates increased stability (ipTM 0.47, pTM 0.68) compared to the free dimer (0.25, 0.59), supporting fatty acid–induced stabilization. NCL partial sequence (residues 307–647) showed low AlphaFold scores (0.11–0.21 ipTM), whereas RBD1–RBD2 domains yielded higher values (0.28 ipTM). Docking predicted stronger interaction with partial NCL (–893.8 kcal/mol) than with RBDs (–816.2 kcal/mol). Integrin predictions indicated strong binding: αVβ3 (–1212.9 kcal/mol), αVβ6 (–906.9 kcal/mol), α5β1 (–856 kcal/mol); αVβ3 preserved the BaMtx dimer, while αVβ6 required monomer dissociation. These results support that fatty acid binding stabilizes PLA₂ dimers and that BaMtx interacts with TNBC biomarkers, with αVβ3 showing the highest predicted affinity, highlighting its potential as a lead molecule for anticancer strategies against this aggressive breast cancer subtype. Financial support: PROCIENCIA–Peru (PE501087970-2024); VRIP–UNMSM–Peru (B25100011); FONDECYT #1241547.
Modulation of mitochondrial gene expression by Pictobin, in tumoral and non-tumorous mammary cell lines (V)
Raul Rivas-Amado1, Félix Urra2, Fanny Lazo1, Christopher Almarza1, Tania Broncano1, Anthony Salcedo1, Armando Yarlequé1 Dan Vivas-Ruíz1
1Grupo de Investigación de Toxinas de Origen Animal y sus Antivenenos (TOXIVEN) – Laboratorio de Biología Molecular, Facultad de Ciencias Biológicas, Universidad Nacional Mayor de San Marcos, Lima-Perú
2Laboratorio de Plasticidad Metabólica y Bioenergética, Programa de Farmacología Molecular y Clínica, Facultad de Medicina, Universidad de Chile, Santiago, Chile
Venoms from Viperidae snakes contain a wide diversity of enzymes. Pictobin, a thrombin-like enzyme from Bothrops pictus venom, has shown antitumor activity associated with mitochondrial dysfunction in triple-negative breast cancer cells (MDA-MB-231). Here, its effect on the expression of genes related to mitochondrial bioenergetics was evaluated in MDA-MB-231 and non-tumorous breast cells (RMF-621). Pictobin, purified through three chromatographic steps, was applied at subtoxic doses (20 μg/mL) to both cell lines. Total RNA was extracted, and qPCR was performed for four bioenergetics-related genes: Cyt C, ANT-3, SLC2A1, and MT-C1B. In MDA-MB-231 cells, Pictobin increased Cyt C (potential apoptotic activation), ANT-3 (ATP transport), and SLC2A1 (glucose uptake), without changes in MT-C1B. In RMF-621 cells, it reduced Cyt C and MT-C1B without affecting ANT-3 or SLC2A1. These findings suggest phenotype-dependent modulation, enhancing apoptotic and metabolic adaptation mechanisms in tumor cells while limiting bioenergetic impact in non-tumor cells. Pictobin thus emerges as a potential selective antitumor modulator, supporting further studies to elucidate its molecular pathways and therapeutic feasibility. Financial support: VRIP-UNMSM (PCONFIGI N° B23100451 RR N° 006081-R-23) and FONDECYT#1241547.
Caught in the Kv web: screening arachnid venoms for modulators of Kv7.2/7.3 channels
Daniela Rojas-Azofeifa, Luca T Rieder, Andrew Walker, Linda Blomster, Glenn F King
Institute for Molecular Bioscience, University of Queensland, Australia
Spider venoms are a rich source of disulphide-rich peptides with potent and selective activity on ion channels. We are leveraging this natural diversity to identify modulators of Kv7.2/7.3 channels (encoded by KCNQ2/3), which underlie the neuronal M-current and play a critical role in controlling excitability. Gain-of-function (GoF) mutations in these channels are increasingly recognised in patients with developmental and epileptic encephalopathies (DEEs), many of whom are resistant to current antiepileptic treatments. To date, no approved therapies exist that specifically target GoF Kv7.2/7.3 dysfunction.Using high-throughput electrophysiology and spider venom fraction screening, we identified two novel peptides that act as negative modulators of voltage-dependent Kv7.2/7.3 activation. These represent the first venom-derived peptides shown to shift Kv7.2/7.3 gating in a manner that may counteract GoF mutations and restore more physiological excitability. Our findings support the potential of spider venom peptides as scaffolds for precision therapeutics targeting Kv7.2/7.3-related epilepsies. Ongoing work focuses on screening and identifying more venoms and peptides.
Recombinant expression of the metalloprotease domain of Pictolysin-III in Escherichia coli BL21 (DE3) and Pichia pastoris (KM71H) (V)
Jorge Alejandro Roque, Daniel Torrejón, Edith Rodríguez, Felix Urra, Armando Yarlequé, Dan Vivas-Ruiz
Animal Toxins and Antivenoms Research Group (TOXIVEN) – Molecular Biology Laboratory, Faculty of Biological Sciences, Universidad Nacional Mayor de San Marcos, Lima, Peru
Pictolysin-III (Pic-III) is a P-III class snake venom metalloprotease from Bothrops pictus, previously shown to disrupt the actin cytoskeleton, impair mitochondrial respiration, block glycolysis, and sensitize triple-negative breast cancer cells to BCL-2 inhibition. To assess whether these effects are retained within the metalloprotease domain, we engineered a catalytically variant preserving structural integrity. The gene was codon-optimized and cloned into pET101 for expression in Escherichia coli BL21 Star™(DE3) and into pPICZαA for secretory expression in Pichia pastoris KM71H. In E. coli, IPTG induction yielded 5.12 ± 0.52 mg/L soluble protein, with 4.68 ± 0.25 mg/L recovered at >90% purity by Ni-NTA chromatography. In P. pastoris, methanol induction produced 4.27 ± 0.09 mg/L secreted protein, with 3.42 ± 0.12 mg/L recovered at ~85% purity. SDS–PAGE and Western blot confirmed product identity in both systems. This comparative approach highlights differences in yield, solubility, and post-translational modifications, providing a basis for functional assays to determine whether the bioenergetic and chemosensitizing properties of Pic-III are intrinsic to its metalloprotease domain. Financial support: CONTRATO N. º PE501088550-2024-PROCIENCIA; VRIP B25100061.
Identification of thrombin-mediated protease-activated receptor 1 signalling in snake venom-induced haemorrhages
Janet Storm, Mia Halliwell, Nicholas R Casewell
Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
Bleeding disorders caused by haemorrhage and coagulopathy are potentially lethal in snake envenoming. Local haemorrhage is caused by the degradation of the extracellular matrix of blood vessels by venom metalloproteinases and hyaluronidases, but the cause of systemic haemorrhage, in which vascular endothelium is damaged, is not fully understood. To determine the effect of venom on barrier integrity of human dermal blood microvascular endothelial cells (HDBMEC), transendothelial electrical resistance (TEER) was performed with nine snake venoms from diverse localities. Haemotoxic venoms caused a concentration-dependent effect on HDBMEC barrier integrity with a rapid decrease and recovery of barrier integrity, resembling the effect of thrombin, used as control. To identify which venom toxins could be responsible, serine protease, metalloproteinase and phospholipase A2 inhibitors were used, identifying a role for mainly serine proteases. Thrombin is also a serine protease, and its effect on HDBMEC barrier integrity was fully inhibited by two thrombin inhibitors and these also inhibited the effect of venom from Echis romani, Bothrops asper and Oxyuranus scutellatus. To investigate whether the thrombin-like effect on barrier function was due to venom-induced prothrombin activation, TEER was performed in serum-free culture medium, leading to a diminished effect on barrier integrity. Using a chromogenic substrate for thrombin, we demonstrated that these venoms produce thrombin in serum-containing medium, indicating that the presence of prothrombin in foetal bovine serum was critical for the observed effect on barrier function. Thrombin is known to reduce endothelial barrier integrity by cleaving protease-activated receptor 1 (PAR1), a G protein-coupled receptor expressed on endothelial cells and involved in haemostasis. The PAR1 inhibitor Vorapaxar abolished the effect of both thrombin and venom on HDBMEC barrier integrity, identifying the likely critical role of PAR1 signalling in systemic haemorrhage.
Venom composition and venom gland transcriptomics reveal intra- and interspecific variation in the B. neuwiedi complex
Bárbara S Teixeira-Costa1,2, Mônica Colombini2, Juan David Bayona-Serrano3, Ana Maria Moura-da-Silva2, Luciana A Freitas-de-Sousa2, Felipe G Grazziotin1
1Laboratório de Coleções Zoológicas, Instituto Butantan, Avenida Vital Brasil 1500, São Paulo, SP, Brazil
2Laboratório de Imunopatologia, Instituto Butantan, Avenida Vital Brasil 1500, São Paulo, SP, Brazil
3Laboratório de Toxinologia Aplicada, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, Avenida Vital Brasil 1500, São Paulo, SP, Brazil
Snake venoms are complex mixtures of several toxins, whose composition can vary both within and between species. Describing this variability provides opportunities to advance our understanding of organismal evolution and to support effective public health actions. Snakes of the Bothrops neuwiedi complex are currently classified as B. marmoratus and B. neuwiedi. Although their morphology and genetic variation are relatively well studied, the variability in their venoms remains largely unexplored. Here we evaluate variation in venom composition and toxin expression levels across multiple populations of B. marmoratus and B. neuwiedi. We analyzed six specimens of B. neuwiedi from the Brazilian states of Rio de Janeiro, Bahia, and Minas Gerais, and three specimens of B. marmoratus from Minas Gerais and Goiás. We evaluated their venom composition through HPLC and SDS-PAGE. We also evaluated the venom glands through RNA-seq based sequencing. Our results reveal substantial presence of SVMP (snake venom metalloproteinases) in both species, as evidenced by 20 to 100 kDa bands in the SDS-PAGE analysis. Other dominant toxin classes include snake venom serine proteases, PLA2s (phospholipases A2) and C-type lectins. We identified SVMPs as the predominant component in B. neuwiedi venoms. Furthermore, our analysis indicates potential geographic and ontogenetic variation, particularly PLA2 levels. Similarly, SVMPs are the main component in B. marmoratus venoms. Geographic variation in venom compositions was also detected in this species, and our results suggest that B. marmoratus venoms are more diverse than those of B. neuwiedi. Regarding their venom gland transcriptomes, we could confirm the results previously observed for their venom composition. This preliminary study reveals both intra- and interspecific variation in venom composition and transcriptomes among populations of the B. neuwiedi complex, which will be further explored through mass spectrometry analyses.
Design and synthesis of a multiepitope protein based on two phospholipases A₂ from Bothrops pictus venom (V)
Daniel Torrejón1, Raúl Rivas1, Víctor Otárola1, Tania Broncano1, Fanny Lazo1, Armando Yarlequé1, Félix Urra2, Dan Vivas-Ruiz1
1Laboratorio de Biología Molecular, Facultad de Ciencias Biológicas, Universidad Nacional Mayor de San Marcos (UNMSM), Lima, Perú
2Laboratorio de Plasticidad Metabólica y Bioenergética, Programa de Farmacología Clínica y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
Phospholipases A₂ (PLA₂s) are among the predominant toxins in Bothrops venoms and are associated with severe myotoxic, hemolytic, and pro-inflammatory effects. BpMtx, a Lys49-PLA₂, and BpTx-I, an Asp49-PLA₂, are two PLA₂s recently identified from B. pictus venom. This study aimed to design and obtain a multiepitope protein derived from these two enzymes. The design began with in silico prediction of linear epitopes, which were synthesized using the SPOT synthesis technique on cellulose membranes. Their antigenicity was evaluated against the polyvalent anti-bothropic serum produced by the National Institute of Health (INS, Lima). Peptides with the highest recognition were selected and assembled into an optimized synthetic gene, which was integrated into the pET-101 plasmid. The recombinant vector Bpic-abPL was propagated in Escherichia coli TOP10 and subsequently expressed in the Star BL21(DE3) strain via IPTG induction. The recombinant protein was purified by affinity chromatography (His-Tag), and its expression was confirmed by SDS-PAGE and Western blot. Immunorecognition results of the peptides synthesized on the membrane enabled the selection of three potential epitopes for BpTx-I (MK-X(10)-SY, YG-X(20)-VV, and FR-X(10)-WF) and three for BpMtx (CN-X(23)-YK, DC-X(17)-IV, and KY-X(19)-LE). SDS-PAGE analysis revealed the expression of a protein of approximately 17 kDa, with positive reactivity in ELISA and Western blot assays against the anti-bothropic serum, confirming the conservation of the selected antigenic epitopes. In conclusion, the recombinant expression of a multiepitope protein derived from PLA₂s of B. pictus was successfully achieved. ELISA results revealed improved antigen recognition compared to individual peptides, confirming the preservation of selected epitopes. This recombinant construct represents a promising tool for the development of new immunization strategies and is now ready for neutralization assays. Financial support: PE501088550-2024-PROCIENCIA-CONCYTEC; FONDECYT#1241547.
Overview of initial results in solving the disaster of poisonous snakebite victims in Vietnam since 1990 (V)
Kiem Xuan Trinh
Vietnam Society of Toxicology (VST) and Vietnam Institute of Toxicology (VIT), Vietnam
Objective: Vietnam (VN) is an agricultural & tropical country. It is very convenient for developing of the poisonous snakes. They are the perpetrators harming up to 30,000 (thirty thousand) victims per year with a very high mortality rate (19.5%), because there was no anti-venom (AV). The objective of present research program was to manufacture specific AV to each poisonous snake species, promptly meeting the clinical requirements to save the lives of envenomed victims in VN. According to the guidance of WHO and David Warrell, 03 venomous snake families with 13 species of medical importance in VN have been established. 06 specific AV types with each most dangerous and common venomous snake have been successfully researched and manufactured according to the technical process F(ab’)2. They are Naja kaouthia, Calloselasma rhodostoma, Bungarus candidus and Bungarus multicinctus, Ophiophagus hannah, Naja siamensis. After meeting all quality inspection criteria at the National Institute of Vaccine and Bio-products, the Ministry of Health of VN, AVs have been allowed to promptly apply clinical emergency to save the lives of 4,813 (Four thousand, eight hundred and thirteen) envenomed victims, who were threatened by death. The mortality rate of severely envenomed victim group had decreased from 19,5% to 0.24%. Permanent deformity rate had reduced from 14% to 05%. Amputation rate had reduced from 11% to 01%. However, the above research results were only the initial step and limited in the laboratory. Snakebite has been still neglected in VN. We urgently call for the attention of the State, domestic and foreign philanthropists to support the development of manufacturing AV program in order to timely save the lives of many thousands of envenomed victims in VN, Laos and Cambodia.
Two Snake Toxins, Two Stories: Divergent Effects of Asp49- and Lys49-PLA₂ from Bothrops pictus on Mitochondrial Bioenergetics (V)
Cristopher Almarza1,2, Alex Proleon2,3, Yarela Herrera1,2, Gonzalo Ramirez1,2, Pedro Lobos1,2, Ignacio Contreras1,2, Armando Yarleque2,3, Dan Vivas-Ruiz2,3, Félix Urra1,2
1Laboratory of Metabolic Plasticity and Bioenergetics, Institute of Biomedical Sciences (ICBM), Faculty of Medicine, University of Chile. Av. Independencia 1027, Santiago, Chile
2Network for Snake Venom Research and Drug Discovery, Av. Independencia 1027, Santiago, Chile
3Laboratory of Molecular Biology, Faculty of Biological Sciences, Universidad Nacional Mayor de San Marcos, Peru. Av. Venezuela Cdra 34 S/N, Ciudad Universitaria, Lima 01, Peru
Your abstract goes here. In this study, we characterize two phospholipases from the venom of Bothrops pictus that have a significant difference in their active site: ASP-49 or LYS-49, which makes the latter incapable of hydrolyzing phospholipids. Here we present an expanded and comparative view of the cellular effects of these toxins using proliferation curves obtained with cell impedance techniques (xCelLigence RTCA) in four cell lines: Hela, MCF-7, RMF-621, and MDA-MB-231. We also evaluated their effect on mitochondrial function by measuring mitochondrial membrane potential (TMRM) and mitochondrial reactive oxygen species (mitoSOX) by flow cytometry, NADH levels by autofluorescence, Cytosolic Ca²⁺ measurement by fluorescence (Fluo-4), oxygen consumption, and extracellular acidification using Seahorse XF96 in highly malignant MDA-MB-231 cell lines. Our results indicate that both LYS-49 and ASP-49 alter growth curves, especially in MDA-MB-231, causing a decrease in cell impedance. However, they show opposite effects when analyzing mitochondrial function: LYS-49 increases mitochondrial ROS, reduces cytosolic calcium levels, decreases basal respiration and maximum respiration, inducing a more glycolytic bioenergetic remodeling, while ASP-49 does not produce any detectable metabolic change. Therefore, we suggest that the effect of svPLA2 is selective for MDA-MB-231 and that the molecular mechanism could be substantially different between the two variants. Acknowledgments: Vicerrectorado de Investigación y Posgrado–UNMSM-Peru: PCONFIGI N° B22100141 (DV-R), PROCIENCIA-Peru Grant PE501087970-2024 (AY, DV-R), FONDECYT Grant #1241547 (FAU), FONDECYT Postdoctoral fellowship #3240639 (PL), PhD Scholarship ANID-#21253051 (GR), PhD Scholarship ANID-#21222256 (YH), FONDEQUIP Grant #EQM220164 (FAU).
B-cell epitope mapping of principal toxins from peruvian Bothrops pictus snake venom using SPOT synthesis (V)
Víctor Otarola1, Alex Proleon1, Raul Rivas1, Alejando Roque1, Tania Broncano1, Carlos Chavez2, Armando Yarlequé1, Dan Vivas-Ruiz1
1Laboratorio de Biología Molecular, Facultad de Ciencias Biológicas, Universidad Nacional Mayor de San Marcos, Av. Venezuela Cdra 34 S/N, Ciudad Universitaria, Lima 01, Peru
2Departamento de Bioquímica-Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
Bothrops pictus is an endemic Peruvian snake whose venom, along with that of other Bothrops species, is used to produce the Peruvian antibothropic polyvalent antivenom (Instituto Nacional de Salud, Peru). Venom toxins are immunogenic and induce antibody production; however, the immune response varies among toxin families. In this study, peptides from major B. pictus venom toxins were synthesized on cellulose membranes using the SPOT technique with a MultiPep1 CEM synthesizer. Fourteen–amino acid peptides were generated with a three–residue sliding window from Pictolysin-III (SVMP, WLW15890), BpMtx (PLA₂, QNM80738), Pictobin (SVSP, AGZ87932) and L-amino acid oxidase (LAAO, AHN91985), excluding signal and propeptide regions. Arrays were probed with the Peruvian antivenom, and antigen–antibody interactions visualized with DAB substrate. Positive reactivity was detected in 41/136 SVMP peptides (restricted to the metalloproteinase domain), 0/40 PLA₂, 10/80 SVSP, and 87/163 LAAO peptides. Sequence alignment with homologous toxins from other Viperidae identified conserved B-cell epitopes, selecting 5, 3, and 6 peptides for SVMP, SVSP, and LAAO, respectively. These were mapped onto AlphaFold-predicted 3D models and analysed in silico with the IEDB. Results reveal that metalloproteinases, serine proteases, and LAAOs contain highly immunogenic regions, whereas PLA₂s show minimal reactivity. This supports targeting highly immunogenic toxin domains to enhance antivenom efficacy and improving the immunogenic profile of poorly recognized toxins such as PLA₂s, particularly since SVMPs represent 40–50% of Bothrops venoms. Financial support: ProCIENCIA-CONCYTEC: CONTRATO N.º PE501088550-2024-PROCIENCIA.
Listeriolysin O mutant LLOY406A: A Potential Therapeutic Agent Against Cancer Blood Cells
Apolonija Bedina Zavec1, Rebeka Podgrajšek1, Ana Špilak1, Maja Jamnik1, Gašper Šolinc1, Matic Kisovec1, Veronika Kralj-Iglič2, Gregor Anderluh1, Marjetka Podobnik1
1Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, SI-1000 Ljubljana, Slovenia
2Biomedical Research Group, Faculty of Health Sciences, University of Ljubljana, SI-1000 Ljubljana, Slovenia
Listeriolysin O (LLO) is a toxin of the intracellular pathogen Listeria monocytogenes that forms pores in cholesterol-rich lipid membranes of host cells. LLO has an optimum pH at 5.5, a condition found in late endosomes, while it can also bind to the membrane at neutral pH and form pores and damage cells. Mutant LLOY406A with a substitution (Try to Ala) at site 406 can bind to membranes and oligomerize similarly to wtLLO, but the final membrane insertion step requires an acidic pH. The LLOY406A mutant is less hemolytic than wtLLO and has a pH optimum at pH 5-6, which may be of interest for applications in medicine. In this study, we tested the effects of wtLLO and LLOY406A on healthy blood cells (PBMCs) and cancer blood cells (the myeloid leukemia cell line K562, the T lymphocyte cell line Jurkat, and the B lymphocyte cell line Raji). The results show that healthy blood cells are more resistant to treatment with wtLLO and LLOY406A than cancer cells. The greatest differences between healthy and cancer cells were observed when the cells were treated with LLOY406A at pH 6.5. Tumor tissue typically has an extracellular pH of 6.5 to 6.9 due to the extracellular acidosis of cancer cells. The half maximal effective concentration (EC50) of LLOY406A at pH 6.5 was 5.8 times higher in PBMC cells than in K562, 2.2 times higher than in Raji, and 31.9 times higher than in Jurkat cells. In addition, the LLOY406A mutant was significantly less toxic than wtLLO under physiological conditions, making it a potential candidate for stimulus-dependent applications and cancer treatment. The greatest difference in survival between cancer and healthy cells was achieved by treating cells with 100 nM LLOY406A at pH 6.5. According to our in vitro results, 100 nM LLOY406A is therefore the most promising concentration or starting concentration for the in vivo experiments for the treatment of blood cancers.
