1
|
Lim ASS, Tan KY, Tan CH. Immunoreactivity and neutralization efficacy of Pakistani Viper Antivenom (PVAV) against venoms of Saw-scaled Vipers (Echis carinatus subspp.) and Western Russell's Vipers (Daboia russelii) from the Indian subcontinent. Acta Trop 2024; 250:107099. [PMID: 38097152 DOI: 10.1016/j.actatropica.2023.107099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 12/04/2023] [Accepted: 12/11/2023] [Indexed: 12/31/2023]
Abstract
Snakebite envenoming (SBE) is a priority Neglected Tropical Disease listed by the World Health Organization. South Asia is heavily affected, and virtually all countries in the region import polyvalent antivenom products from India for clinical use. The imported antivenoms, however, have suboptimal effectiveness due to geographical venom variation. Recently, a domestic bivalent product, named Pakistani Viper Antivenom (PVAV) has been developed specifically for Pakistani vipers, Echis carinatus sochureki and Daboia russelii. As a bivalent viperid antivenom, it is unknown yet if PVAV exhibits higher immunological binding and neutralization activities against viper venoms from distant locales compared with polyvalent antivenoms manufactured in India. This study thus examined the preclinical efficacy of PVAV against venoms of Western Russell's Vipers and Saw-scaled Viper subspecies from selected locales in the Indian subcontinent. PVAV generally outperformed the commonly used VINS polyvalent antivenom (VPAV, manufactured in India) in binding toward venoms, and showed superior or comparable neutralization efficacy against the venom procoagulant and hemorrhagic effects of Saw-scaled Vipers as well as Russell's Vipers from Pakistan and Sri Lanka. Based on normalized potency values, PVAV is far more potent than VPAV in neutralizing the lethality of all viper venoms, except that of the Indian Russell's Viper. The study shows conserved antigenicity of toxins responsible for major toxicity across these viperid venoms, and suggests the feasible production of a viper-specific antivenom with higher potency and broader geographical utility for the region.
Collapse
Affiliation(s)
- Andy Shing Seng Lim
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
| |
Collapse
|
2
|
Tan CH, Tan KY, Tan NH. De Novo Assembly of Venom Gland Transcriptome of Tropidolaemus wagleri (Temple Pit Viper, Malaysia) and Insights into the Origin of Its Major Toxin, Waglerin. Toxins (Basel) 2023; 15:585. [PMID: 37756011 PMCID: PMC10537322 DOI: 10.3390/toxins15090585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/11/2023] [Accepted: 09/15/2023] [Indexed: 09/28/2023] Open
Abstract
The venom proteome of Temple Pit Viper (Tropidolaemus wagleri) is unique among pit vipers, characterized by a high abundance of a neurotoxic peptide, waglerin. To further explore the genetic diversity of its toxins, the present study de novo assembled the venom gland transcriptome of T. wagleri from west Malaysia. Among the 15 toxin gene families discovered, gene annotation and expression analysis reveal the dominating trend of bradykinin-potentiating peptide/angiotensin-converting enzyme inhibitor-C-type natriuretic peptide (BPP/ACEI-CNP, 76.19% of all-toxin transcription) in the transcriptome, followed by P-III snake venom metalloproteases (13.91%) and other toxins. The transcript TwBNP01 of BPP/ACEI-CNP represents a large precursor gene (209 amino acid residues) containing the coding region for waglerin (24 residues). TwBNP01 shows substantial sequence variations from the corresponding genes of its sister species, Tropidolaemus subannulatus of northern Philippines, and other viperid species which diversely code for proline-rich small peptides such as bradykinin-potentiating peptides (BPPs). The waglerin/waglerin-like peptides, BPPs and azemiopsin are proline-rich, evolving de novo from multiple highly diverged propeptide regions within the orthologous BPP/ACEI-CNP genes. Neofunctionalization of the peptides results in phylogenetic constraints consistent with a phenotypic dichotomy, where Tropidolaemus spp. and Azemiops feae convergently evolve a neurotoxic trait while vasoactive BPPs evolve only in other species.
Collapse
Affiliation(s)
- Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
- College of Life Sciences and Medicine, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia; (K.Y.T.); (N.H.T.)
| | - Nget Hong Tan
- Department of Molecular Medicine, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia; (K.Y.T.); (N.H.T.)
| |
Collapse
|
3
|
Tan CH, Tan KY, Ng TS, Tan NH, Chong HP. De Novo Venom Gland Transcriptome Assembly and Characterization for Calloselasma rhodostoma (Kuhl, 1824), the Malayan Pit Viper from Malaysia: Unravelling Toxin Gene Diversity in a Medically Important Basal Crotaline. Toxins (Basel) 2023; 15:toxins15050315. [PMID: 37235350 DOI: 10.3390/toxins15050315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 04/24/2023] [Accepted: 04/26/2023] [Indexed: 05/28/2023] Open
Abstract
In Southeast Asia, the Malayan Pit Viper (Calloselasma rhodostoma) is a venomous snake species of medical importance and bioprospecting potential. To unveil the diversity of its toxin genes, this study de novo assembled and analyzed the venom gland transcriptome of C. rhodostoma from Malaysia. The expression of toxin genes dominates the gland transcriptome by 53.78% of total transcript abundance (based on overall FPKM, Fragments Per Kilobase Million), in which 92 non-redundant transcripts belonging to 16 toxin families were identified. Snake venom metalloproteinase (SVMP, PI > PII > PIII) is the most dominant family (37.84% of all toxin FPKM), followed by phospholipase A2 (29.02%), bradykinin/angiotensin-converting enzyme inhibitor-C-type natriuretic peptide (16.30%), C-type lectin (CTL, 10.01%), snake venom serine protease (SVSP, 2.81%), L-amino acid oxidase (2.25%), and others (1.78%). The expressions of SVMP, CTL, and SVSP correlate with hemorrhagic, anti-platelet, and coagulopathic effects in envenoming. The SVMP metalloproteinase domains encode hemorrhagins (kistomin and rhodostoxin), while disintegrin (rhodostomin from P-II) acts by inhibiting platelet aggregation. CTL gene homologues uncovered include rhodocytin (platelet aggregators) and rhodocetin (platelet inhibitors), which contribute to thrombocytopenia and platelet dysfunction. The major SVSP is a thrombin-like enzyme (an ancrod homolog) responsible for defibrination in consumptive coagulopathy. The findings provide insight into the venom complexity of C. rhodostoma and the pathophysiology of envenoming.
Collapse
Affiliation(s)
- Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Tzu Shan Ng
- Department of Molecular Medicine, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Nget Hong Tan
- Department of Molecular Medicine, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Ho Phin Chong
- Department of Pharmacology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| |
Collapse
|
4
|
Lim ASS, Tan KY, Quraishi NH, Farooque S, Khoso ZA, Ratanabanangkoon K, Tan CH. Proteomic Analysis, Immuno-Specificity and Neutralization Efficacy of Pakistani Viper Antivenom (PVAV), a Bivalent Anti-Viperid Antivenom Produced in Pakistan. Toxins (Basel) 2023; 15:toxins15040265. [PMID: 37104203 PMCID: PMC10145215 DOI: 10.3390/toxins15040265] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 03/24/2023] [Indexed: 04/05/2023] Open
Abstract
Snakebite envenoming is a neglected tropical disease prevalent in South Asia. In Pakistan, antivenoms are commonly imported from India despite the controversy over their effectiveness. To solve the problem, the locals have developed the Pakistani Viper Antivenom (PVAV), raised against Sochurek’s Saw-scaled Viper (Echis carinatus sochureki) and Russell’s Viper (Daboia russelii) of Pakistani origin. This study is set to evaluate the composition purity, immuno-specificity and neutralization efficacy of PVAV. Chromatographic and electrophoretic profiling coupled with proteomic mass spectrometry analysis showed PVAV containing high-purity immunoglobulin G with minimum impurities, notably the absence of serum albumin. PVAV is highly immuno-specific toward the venoms of the two vipers and Echis carinatus multisquamatus, which are indigenous to Pakistan. Its immunoreactivity, however, reduces toward the venoms of other Echis carinatus subspecies and D. russelii from South India as well as Sri Lanka. Meanwhile, its non-specific binding activities for the venoms of Hump-nosed Pit Vipers, Indian Cobras and kraits were extremely low. In the neutralization study, PVAV effectively mitigated the hemotoxic and lethal effects of the Pakistani viper venoms, tested in vitro and in vivo. Together, the findings suggest the potential utility of PVAV as a new domestic antivenom for the treatment of viperid envenoming in Pakistan.
Collapse
Affiliation(s)
- Andy Shing Seng Lim
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Naeem H. Quraishi
- Snake Antivenom/Antirabies Serology Laboratory, Department of Community Medicine & Public Health Sciences, People’s University of Medical and Health Sciences for Women, Nawabshah 67450, Pakistan
| | - Saud Farooque
- Snake Antivenom/Antirabies Serology Laboratory, Department of Community Medicine & Public Health Sciences, People’s University of Medical and Health Sciences for Women, Nawabshah 67450, Pakistan
| | - Zahoor Ahmed Khoso
- Snake Antivenom/Antirabies Serology Laboratory, Department of Community Medicine & Public Health Sciences, People’s University of Medical and Health Sciences for Women, Nawabshah 67450, Pakistan
| | - Kavi Ratanabanangkoon
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 73170, Thailand
| | - Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| |
Collapse
|
5
|
Lee LP, Tan CH, Khomvilai S, Sitprija V, Chaiyabutr N, Tan KY. Characterizing and applying immunoglobulins in snakebite diagnostics: A simple and rapid venom detection assay for four medically important snake species in Southeast Asia. Int J Biol Macromol 2023; 236:123727. [PMID: 36863668 DOI: 10.1016/j.ijbiomac.2023.123727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 01/28/2023] [Accepted: 02/13/2023] [Indexed: 03/04/2023]
Abstract
Snakebite envenoming is a medical emergency requiring urgent and specific treatment. Unfortunately, snakebite diagnostics are scarce, time-consuming and lacking specificity. Hence, this study aimed to develop a simple, quick and specific snakebite diagnostic assay using animal antibodies. Anti-venom horse immunoglobulin G (IgG) and chicken immunoglobulin Y (IgY) were produced against the venoms of four major medically important snake species in Southeast Asia, i.e., the Monocled Cobra (Naja kaouthia), Malayan Krait (Bungarus candidus), Malayan Pit Viper (Calloselasma rhodostoma), and White-lipped Green Pit Viper (Trimeresurus albolabris). Different capture:detection configurations of double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) were constructed using both immunoglobulins, and the horse IgG:IgG-HRP configuration was found to be most selective and sensitive in detecting the corresponding venoms. The method was further streamlined to develop a rapid immunodetection assay, which is able to produce a visual color change within 30 min for discrimination between different snake species. The study shows it is feasible to develop a simple, quick and specific immunodiagnostic assay using horse IgG, which can be derived directly from antisera prepared for antivenom production. The proof-of-concept indicates it is a sustainable and affordable approach in keeping with on-going antivenom manufacturing activities for specific species in the region.
Collapse
Affiliation(s)
- Louisa Pernee Lee
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia.
| | - Sumana Khomvilai
- Queen Saovabha Memorial Institute, Thai Red Cross Society, 10330 Bangkok, Thailand
| | - Visith Sitprija
- Queen Saovabha Memorial Institute, Thai Red Cross Society, 10330 Bangkok, Thailand
| | - Narongsak Chaiyabutr
- Queen Saovabha Memorial Institute, Thai Red Cross Society, 10330 Bangkok, Thailand
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia.
| |
Collapse
|
6
|
Palasuberniam P, Tan KY, Chan YW, Blanco FB, Tan CH. Decomplexation proteomic analysis and purity assessment of a biologic for snakebite envenoming: Philippine Cobra Antivenom. Trans R Soc Trop Med Hyg 2023:6972591. [PMID: 36611268 DOI: 10.1093/trstmh/trac125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 11/02/2022] [Accepted: 12/10/2022] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Philippine Cobra Antivenom (PCAV) is the only snake antivenom manufactured in the Philippines. It is used clinically to treat envenoming caused by the Philippine Spitting Cobra (Naja philippinensis). While PCAV is effective pharmacologically, it is crucial to ensure the safety profile of this biologic that is derived from animal plasma. METHODS This study examined the composition purity of PCAV through a decomplexation proteomic approach, applying size-exclusion chromatography (SEC), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and tandem mass spectrometry liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS SDS-PAGE and SEC showed that the major protein in PCAV (constituting ∼80% of total proteins) is approximately 110 kDa, consistent with the F(ab')2 molecule. This protein is reducible into two subunits suggestive of the light and heavy chains of immunoglobulin G. LC-MS/MS further identified the proteins as equine immunoglobulins, representing the key therapeutic ingredient of this biologic product. However, protein impurities, including fibrinogens, alpha-2-macroglobulins, albumin, transferrin, fibronectin and plasminogen, were detected at ∼20% of the total antivenom proteins, unveiling a concern for hypersensitivity reactions. CONCLUSIONS Together, the findings show that PCAV contains a favorable content of F(ab')2 for neutralization, while the antibody purification process awaits improvement to minimize the presence of protein impurities.
Collapse
Affiliation(s)
- Praneetha Palasuberniam
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University Malaysia Sabah, 88400 Kota Kinabalu, Sabah, Malaysia.,Venom Research & Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Yi Wei Chan
- Department of Emergency Medicine, Ospital ng Muntinlupa, 1781 Muntinlupa, Manila, Philippines
| | - Francis Bonn Blanco
- Department of Emergency Medicine, Ospital ng Muntinlupa, 1781 Muntinlupa, Manila, Philippines.,Department of Internal Medicine, Davao Medical School Foundation Hospital, 8000 Davao City, Philippines
| | - Choo Hock Tan
- Venom Research & Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| |
Collapse
|
7
|
Blessmann J, Hanlodsomphou S, Santisouk B, Krumkamp R, Kreuels B, Ismail AK, Yong MY, Tan KY, Tan CH. Experience of using expired lyophilized snake antivenom during a medical emergency situation in Lao People's Democratic Republic--A possible untapped resource to tackle antivenom shortage in Southeast Asia. Trop Med Int Health 2023; 28:64-70. [PMID: 36416013 DOI: 10.1111/tmi.13833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVES To evaluate the safety and efficacy of expired lyophilized snake antivenom of Thai origin during a medical emergency in 2020/2021 in Lao People's Democratic Republic. METHODS Observational case series of patients with potentially life-threatening envenoming who consented to the administration of expired antivenom between August 2020 and May 2022. RESULTS A total of 31 patients received the expired antivenom. Malayan pit vipers (Calloselasma rhodostoma) were responsible for 26 (84%) cases and green pit vipers (Trimeresurus species) for two cases (6%). In three patients (10%) the responsible snake could not be identified. Of these, two presented with signs of neurotoxicity and one with coagulopathy. A total of 124 vials of expired antivenom were administered. Fifty-nine vials had expired 2-18 months earlier, 56 vials 19-36 months and nine vials 37-60 months before. Adverse effects of variable severity were observed in seven (23%) patients. All 31 patients fully recovered from systemic envenoming. CONCLUSIONS Under closely controlled conditions and monitoring the use of expired snake antivenom proved to be effective and safe. Discarding this precious medication is an unnecessary waste, and it could be a valuable resource in ameliorating the current shortage of antivenom. Emergency use authorization granted by health authorities and preclinical testing of expired antivenoms could provide the support and legal basis for such an approach.
Collapse
Affiliation(s)
- Jörg Blessmann
- Department of Implementation Research, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | | | - Bounlom Santisouk
- Department of Emergency Medicine, Setthatirath Hospital, Vientiane, Laos
| | - Ralf Krumkamp
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,German Center for Infection Research, Partner Site Hamburg Lübeck Borstel Riems, Hamburg, Germany
| | - Benno Kreuels
- Department of Implementation Research, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Ahmad Khaldun Ismail
- Department of Emergency Medicine, Universiti Kebangsaan Malaysia, Faculty of Medicine, Kuala Lumpur, Malaysia
| | - Mun Yee Yong
- Department of Pharmacology, Faculty of Medicine, Venom Research and Toxicology Lab, University of Malaya, Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, Protein and Interactomics Lab, University of Malaya, Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, Venom Research and Toxicology Lab, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
8
|
Chan YW, Tan CH, Heh CH, Tan KY. An immunoinformatic approach to assessing the immunogenic capacity of alpha-neurotoxins in elapid snake venoms. Front Pharmacol 2023; 14:1143437. [PMID: 37153801 PMCID: PMC10155835 DOI: 10.3389/fphar.2023.1143437] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 03/27/2023] [Indexed: 05/10/2023] Open
Abstract
Introduction: Most elapid snakes produce venoms that contain alpha-neurotoxins (α-NTXs), which are proteins that cause post-synaptic blockade and paralysis in snakebite envenoming. However, existing elapid antivenoms are known for their low potency in neutralizing the neurotoxic activity of α-NTXs, while the immunological basis has not been elucidated. Methods: In this study, a structure-based major histocompatibility complex II (MHCII) epitope predictor of horse (Equus caballus), complemented with DM-editing determinant screening algorithm was adopted to assess the immunogenicity of α-NTXs in the venoms of major Asiatic elapids (Naja kaouthia, Ophiophagus hannah, Laticauda colubrina, Hydrophis schistosus, Hydrophis curtus). Results: The scoring metric M2R, representing the relative immunogenic performance of respective α-NTXs, showed all α-NTXs have an overall low M2R of <0.3, and most of the predicted binders feature non-optimal P1 anchor residues. The M2R scores correlate strongly (R2 = 0.82) with the potency scores (p-score) generated based on the relative abundances of α-NTXs and the neutralization potency of commercial antivenoms. Discussion: The immunoinformatic analysis indicates that the inferior antigenicity of α-NTXs is not only due to their small molecular size but also the subpar immunogenicity affected by their amino acid composition. Structural modification with conjugation and synthetic epitope as immunogen may potentially enhance the immunogenicity for improved antivenom potency against α-NTXs of elapid snakes.
Collapse
Affiliation(s)
- Yi Wei Chan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Choon Han Heh
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Malaya, Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- *Correspondence: Kae Yi Tan,
| |
Collapse
|
9
|
Tan CH, Wong KY, Huang LK, Tan KY, Tan NH, Wu WG. Snake Venomics and Antivenomics of Cape Cobra ( Naja nivea) from South Africa: Insights into Venom Toxicity and Cross-Neutralization Activity. Toxins (Basel) 2022; 14:toxins14120860. [PMID: 36548757 PMCID: PMC9783313 DOI: 10.3390/toxins14120860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 11/24/2022] [Accepted: 11/30/2022] [Indexed: 12/14/2022] Open
Abstract
Naja nivea (Cape Cobra) is endemic to southern Africa. Envenoming by N. nivea is neurotoxic, resulting in fatal paralysis. Its venom composition, however, has not been studied in depth, and specific antivenoms against it remain limited in supply. Applying a protein decomplexation approach, this study unveiled the venom proteome of N. nivea from South Africa. The major components in the venom are cytotoxins/cardiotoxins (~75.6% of total venom proteins) and alpha-neurotoxins (~7.4%), which belong to the three-finger toxin family. Intriguingly, phospholipase A2 (PLA2) was undetected-this is a unique venom phenotype increasingly recognized in the African cobras of the Uraeus subgenus. The work further showed that VINS African Polyvalent Antivenom (VAPAV) exhibited cross-reactivity toward the venom and immunorecognized its toxin fractions. In mice, VAPAV was moderately efficacious in cross-neutralizing the venom lethality with a potency of 0.51 mg/mL (amount of venom completely neutralized per milliliter of antivenom). In the challenge-rescue model, VAPAV prevented death in 75% of experimentally envenomed mice, with slow recovery from neurotoxicity up to 24 h. The finding suggests the potential para-specific utility of VAPAV for N. nivea envenoming, although a higher dose or repeated administration of the antivenom may be required to fully reverse the neurotoxic effect of the venom.
Collapse
Affiliation(s)
- Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
- Institute of Bioinformatics and Structural Biology, Department of Life Science, National Tsing Hua University, Hsinchu 300044, Taiwan
- Correspondence: or
| | - Kin Ying Wong
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
- Institute of Bioinformatics and Structural Biology, Department of Life Science, National Tsing Hua University, Hsinchu 300044, Taiwan
| | - Li-Kun Huang
- Institute of Bioinformatics and Structural Biology, Department of Life Science, National Tsing Hua University, Hsinchu 300044, Taiwan
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Nget Hong Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Wen-Guey Wu
- Institute of Bioinformatics and Structural Biology, Department of Life Science, National Tsing Hua University, Hsinchu 300044, Taiwan
| |
Collapse
|
10
|
Chan YW, Tan KY, Tan CH. Preclinical assessment of VPEAV, a new trivalent antivenom for elapid snakebite envenoming in the Philippines: Proteomics, immunoreactivity and toxicity neutralization. Toxicon 2022; 220:106942. [DOI: 10.1016/j.toxicon.2022.106942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 09/28/2022] [Accepted: 10/09/2022] [Indexed: 11/06/2022]
|
11
|
Tan KY, Shamsuddin NN, Tan CH. Sharp-nosed Pit Viper (Deinagkistrodon acutus) from Taiwan and China: A comparative study on venom toxicity and neutralization by two specific antivenoms across the Strait. Acta Trop 2022; 232:106495. [PMID: 35504314 DOI: 10.1016/j.actatropica.2022.106495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 04/25/2022] [Accepted: 04/29/2022] [Indexed: 11/01/2022]
Abstract
In East Asia, the Sharp-nosed Pit Viper (Deinagkistrodon acutus) is a medically important venomous snake in Taiwan and China, two geographical areas long separated by the Taiwan Strait. Yet, snake venom variation is little known between specimens found across the Strait. This study thus investigated the intra-species variation of D. acutus venoms from Taiwan (Da-Taiwan) and China (Da-China) in their profiles of gel electrophoresis, toxicity, immunoreactivity and neutralization effect by antivenom. Da-China venom exhibited higher procoagulant, hemorrhagic and lethal activities than Da-Taiwan venom, presumably attributed to the higher abundance of moderate-to-high molecular weight toxins (procoagulants and hemorrhagins) in the venom. The mono-specific antivenoms produced in Taiwan (DaMAV-Taiwan) and China (DaMAV-China) were immunoreactive toward both venoms, and were able to neutralize the venom toxicity to different extents. DaMAV-Taiwan was more efficacious in neutralizing the venom procoagulant and lethal effects, while DaMAV-China was more potent against hemorrhagic effect. The discrepancy in efficacy between the two antivenoms could be due to varying proportions of neutralizing antibodies in the respective products, influenced by techniques of antibody raising and purification. Further study is warranted to elucidate variation in the proteome and antigenicity of D. acutus venom between snakes from Taiwan and China.
Collapse
|
12
|
Tan CH, Tan KY, Wong KY, Tan NH, Chong HP. Equatorial Spitting Cobra ( Naja sumatrana) from Malaysia (Negeri Sembilan and Penang), Southern Thailand, and Sumatra: Comparative Venom Proteomics, Immunoreactivity and Cross-Neutralization by Antivenom. Toxins (Basel) 2022; 14:toxins14080522. [PMID: 36006183 PMCID: PMC9414237 DOI: 10.3390/toxins14080522] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 07/20/2022] [Accepted: 07/22/2022] [Indexed: 11/23/2022] Open
Abstract
The Equatorial Spitting Cobra (Naja sumatrana) is a medically important venomous snake species in Southeast Asia. Its wide geographical distribution implies potential intra-specific venom variation, while there is no species-specific antivenom available to treat its envenoming. Applying a protein-decomplexing proteomic approach, the study showed that three-finger toxins (3FTX), followed by phospholipases A2 (PLA2), were the major proteins well-conserved across N. sumatrana venoms of different locales. Variations were noted in the subtypes and relative abundances of venom proteins. Of note, alpha-neurotoxins (belonging to 3FTX) are the least in the Penang specimen (Ns-PG, 5.41% of total venom proteins), compared with geographical specimens from Negeri Sembilan (Ns-NS, 14.84%), southern Thailand (Ns-TH, 16.05%) and Sumatra (Ns-SU, 10.81%). The alpha-neurotoxin abundance, in general, correlates with the venom’s lethal potency. The Thai Naja kaouthia Monovalent Antivenom (NkMAV) was found to be immunoreactive toward the N. sumatrana venoms and is capable of cross-neutralizing N. sumatrana venom lethality to varying degrees (potency = 0.49–0.92 mg/mL, interpreted as the amount of venom completely neutralized per milliliter of antivenom). The potency was lowest against NS-SU venom, implying variable antigenicity of its lethal alpha-neurotoxins. Together, the findings suggest the para-specific and geographical utility of NkMAV as treatment for N. sumatrana envenoming in Southeast Asia.
Collapse
Affiliation(s)
- Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (K.Y.W.); (H.P.C.)
- Correspondence: or
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (K.Y.T.); (N.H.T.)
| | - Kin Ying Wong
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (K.Y.W.); (H.P.C.)
| | - Nget Hong Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (K.Y.T.); (N.H.T.)
| | - Ho Phin Chong
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (K.Y.W.); (H.P.C.)
| |
Collapse
|
13
|
Ong HL, Tan CH, Lee LP, Khor SM, Tan KY. An immunodetection assay developed using cobra cytotoxin-specific antibodies: Potential diagnostics for cobra envenoming. Toxicon 2022; 216:157-168. [PMID: 35868411 DOI: 10.1016/j.toxicon.2022.07.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 07/13/2022] [Accepted: 07/15/2022] [Indexed: 10/17/2022]
Abstract
Cobra (Naja spp.) envenoming is a life-threatening medical emergency, and a correct diagnosis is crucial to initiating timely and appropriate antivenom treatment. However, snakebite diagnostics remain unavailable in Southeast Asia. This study, therefore, developed an immunodetection assay with a potential diagnostic application for cobra envenoming. The cytotoxin of Naja kaouthia (Thai Monocled Cobra) (Nk-CTX) was purified from its venom to produce CTX-specific antibodies in rabbits and chickens. A double-antibody sandwich enzyme-linked immunosorbent assay was developed using the purified anti-Nk-CTX antibodies (immunoglobulin G and immunoglobulin Y), and its selectivity, specificity, and sensitivity for the venoms of five major cobra species in Southeast Asia (N. kaouthia, Naja sumatrana, Naja sputatrix, and Naja siamensis, Naja philippinensis) were studied. The results showed the immunoassay discriminates cobra venoms from other species commonly implicated in snakebites in Southeast Asia, i.e., the Malayan Krait, Many-banded Krait, King Cobra, Eastern Russell's Viper, Malayan Pit Viper and White-lipped Pit Viper. The immunoassay has a high sensitivity for the five cobra venoms, with detection limits (LoD) ranging from 0.6 to 2.6 ng/ml. Together, the findings suggest the potential diagnostic application of the cytotoxin immunoassay for cobra envenoming. The immunoassay was found to exhibit high immunoreactivity toward ten Asiatic cobra venoms (absorbance>1.5), in contrast to African cobra venoms with low immunoreactivity (absorbance<0.9). Considering the varying CTX antigenicity between Asiatic and African cobras, the immunoassay for African cobras should utilize antibodies produced specifically from the cytotoxins of African cobra venoms.
Collapse
Affiliation(s)
- Hui Ling Ong
- Protein and Interactomics Lab, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Venom Research and Toxicology Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Louisa Pernee Lee
- Venom Research and Toxicology Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Sook Mei Khor
- Department of Chemistry, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Lab, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| |
Collapse
|
14
|
Tan CH, Tan KY, Jackson TNW. Editorial: Venoms and Toxins: Functional Omics and Pharmacological Insights. Front Pharmacol 2022; 13:887513. [PMID: 35571136 PMCID: PMC9093603 DOI: 10.3389/fphar.2022.887513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 04/07/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Timothy N W Jackson
- Australian Venom Research Unit, Department of Biochemistry and Pharmacology, University of Melbourne, Parkville, VIC, Australia
| |
Collapse
|
15
|
Chong HP, Tan KY, Liu BS, Sung WC, Tan CH. Cytotoxicity of Venoms and Cytotoxins from Asiatic Cobras (Naja kaouthia, Naja sumatrana, Naja atra) and Neutralization by Antivenoms from Thailand, Vietnam, and Taiwan. Toxins (Basel) 2022; 14:toxins14050334. [PMID: 35622581 PMCID: PMC9144634 DOI: 10.3390/toxins14050334] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 05/03/2022] [Accepted: 05/04/2022] [Indexed: 02/04/2023] Open
Abstract
Envenoming by cobras (Naja spp.) often results in extensive local tissue necrosis when optimal treatment with antivenom is not available. This study investigated the cytotoxicity of venoms and purified cytotoxins from the Monocled Cobra (Naja kaouthia), Taiwan Cobra (Naja atra), and Equatorial Spitting Cobra (Naja sumatrana) in a mouse fibroblast cell line, followed by neutralization of the cytotoxicity by three regional antivenoms: the Thai Naja kaouthia monovalent antivenom (NkMAV), Vietnamese snake antivenom (SAV) and Taiwanese Neuro bivalent antivenom (NBAV). The cytotoxins of N. atra (NA-CTX) and N. sumatrana (NS-CTX) were identified as P-type cytotoxins, whereas that of N. kaouthia (NK-CTX) is S-type. All venoms and purified cytotoxins demonstrated varying concentration-dependent cytotoxicity in the following trend: highest for N. atra, followed by N. sumatrana and N. kaouthia. The antivenoms moderately neutralized the cytotoxicity of N. kaouthia venom but were weak against N. atra and N. sumatrana venom cytotoxicity. The neutralization potencies of the antivenoms against the cytotoxins were varied and generally low across NA-CTX, NS-CTX, and NK-CTX, possibly attributed to limited antigenicity of CTXs and/or different formulation of antivenom products. The study underscores the need for antivenom improvement and/or new therapies in treating local tissue toxicity caused by cobra envenomings.
Collapse
Affiliation(s)
- Ho Phin Chong
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
| | - Bing-Sin Liu
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli 35053, Taiwan;
| | - Wang-Chou Sung
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli 35053, Taiwan;
- Correspondence: (W.-C.S.); (C.H.T.)
| | - Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
- Correspondence: (W.-C.S.); (C.H.T.)
| |
Collapse
|
16
|
Stazi M, Fabris F, Tan KY, Megighian A, Rubini A, Mattarei A, Negro S, D'Este G, Lista F, Rossetto O, Tan CH, Montecucco C. An agonist of the CXCR4 receptor is therapeutic for the neuroparalysis induced by
Bungarus
snakes envenoming. Clin Transl Med 2022; 12:e651. [PMID: 35075797 PMCID: PMC8787102 DOI: 10.1002/ctm2.651] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/27/2021] [Accepted: 10/31/2021] [Indexed: 11/08/2022] Open
Affiliation(s)
- Marco Stazi
- Department of Biomedical Sciences University of Padova Padova Italy
| | - Federico Fabris
- Department of Biomedical Sciences University of Padova Padova Italy
| | - Kae Yi Tan
- Department of Molecular Medicine Faculty of Medicine University of Malaya Kuala Lumpur Malaysia
| | - Aram Megighian
- Department of Biomedical Sciences University of Padova Padova Italy
| | | | - Andrea Mattarei
- Department of Pharmaceutical and Pharmacological Sciences University of Padova Padova Italy
| | - Samuele Negro
- Department of Biomedical Sciences University of Padova Padova Italy
| | - Giorgia D'Este
- Department of Biomedical Sciences University of Padova Padova Italy
| | - Florigio Lista
- Center of Medical and Veterinary Research of the Ministry of Defense Policlinico Militare Rome Italy
| | - Ornella Rossetto
- Department of Biomedical Sciences University of Padova Padova Italy
| | - Choo Hock Tan
- Department of Pharmacology Faculty of Medicine University of Malaya Kuala Lumpur Malaysia
| | - Cesare Montecucco
- Department of Biomedical Sciences University of Padova Padova Italy
- CNR Institute of Neuroscience Padova Italy
| |
Collapse
|
17
|
Palasuberniam P, Chan YW, Tan KY, Tan CH. Snake Venom Proteomics of Samar Cobra (Naja samarensis) from the Southern Philippines: Short Alpha-Neurotoxins as the Dominant Lethal Component Weakly Cross-Neutralized by the Philippine Cobra Antivenom. Front Pharmacol 2022; 12:727756. [PMID: 35002690 PMCID: PMC8740184 DOI: 10.3389/fphar.2021.727756] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Accepted: 11/24/2021] [Indexed: 11/16/2022] Open
Abstract
The Samar Cobra, Naja samarensis, is endemic to the southern Philippines and is a WHO-listed Category 1 venomous snake species of medical importance. Envenomation caused by N. samarensis results in neurotoxicity, while there is no species-specific antivenom available for its treatment. The composition and neutralization of N. samarensis venom remain largely unknown to date. This study thus aimed to investigate the venom proteome of N. samarensis for a comprehensive profiling of the venom composition, and to examine the immunorecognition as well as neutralization of its toxins by a hetero-specific antivenom. Applying C18 reverse-phase high-performance liquid chromatography (RP-HPLC) and tandem mass spectrometry (LC-MS/MS), three-finger toxins (3FTx) were shown to dominate the venom proteome by 90.48% of total venom proteins. Other proteins in the venom comprised snake venom metalloproteinases, phospholipases A2, cysteine-rich secretory proteins, venom nerve growth factors, L-amino acid oxidases and vespryn, which were present at much lower abundances. Among all, short-chain alpha-neurotoxins (SαNTX) were the most highly expressed toxin within 3FTx family, constituting 65.87% of the total venom proteins. The SαNTX is the sole neurotoxic component of the venom and has an intravenous median lethal dose (LD50) of 0.18 μg/g in mice. The high abundance and low LD50 support the potent lethal activity of N. samarensis venom. The hetero-specific antivenom, Philippine Cobra Antivenom (PCAV, raised against Naja philippinensis) were immunoreactive toward the venom and its protein fractions, including the principal SαNTX. In efficacy study, PCAV was able to cross-neutralize the lethality of SαNTX albeit the effect was weak with a low potency of 0.20 mg/ml (defined as the amount of toxin completely neutralized per milliliter of the antivenom). With a volume of 5 ml, each vial of PCAV may cross-neutralize approximately 1 mg of the toxin in vivo. The findings support the potential para-specific use of PCAV in treating envenomation caused by N. samarensis while underscoring the need to improve the potency of its neutralization activity, especially against the highly lethal alpha-neurotoxins.
Collapse
Affiliation(s)
- Praneetha Palasuberniam
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.,Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University Malaysia Sabah, Kota Kinabalu, Malaysia
| | - Yi Wei Chan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
18
|
Lingam TMC, Tan KY, Tan CH. Capillary leak syndrome induced by the venoms of Russell's Vipers (Daboia russelii and Daboia siamensis) from eight locales and neutralization of the differential toxicity by three snake antivenoms. Comp Biochem Physiol C Toxicol Pharmacol 2021; 250:109186. [PMID: 34508870 DOI: 10.1016/j.cbpc.2021.109186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 08/30/2021] [Accepted: 09/02/2021] [Indexed: 10/20/2022]
Abstract
Snakebite envenomation caused by the Western and Eastern Russell's Vipers (Daboia russelii and Daboia siamensis) may potentially induce capillary leak syndrome (CLS), while the use of antivenom in treating this has not been well examined. This study investigated the CLS-inducing toxicity of Russell's Viper venoms from various sources and examined the neutralization activity of regionally available antivenoms, using a newly devised mouse model. D. russelii venoms demonstrated a more consistent vascular leakage activity (76,000-86,000 CLS unit of vascular leak index, a function of the diameter and intensity of Evans Blue dye extravasation into dermis) than D. siamensis venoms (33,000-88,000 CLS unit). Both species venoms increased hematocrits markedly (53-67%), indicating hemoconcentration. Regional antivenoms (DsMAV-Thailand, DsMAV-Taiwan, VPAV-India) preincubated with the venoms effectively neutralized the CLS effect to different extents. When the antivenoms were administered intravenously post-envenomation (challenge-rescue model), the neutralization was less effective, implying that CLS has a rapid onset that preceded the neutralizing activity of antivenom, and/or the antivenom has limited biodistribution to the venom's inoculation site. In conclusion, Russell's Viper venoms of both species from various locales induced CLS in mice. Antivenoms generally had limited efficacy in neutralizing the CLS effect. Innovative treatment for venom-induced CLS is needed.
Collapse
Affiliation(s)
- Thava Malar Changra Lingam
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| |
Collapse
|
19
|
Palasuberniam P, Tan KY, Tan CH. De novo venom gland transcriptomics of Calliophis bivirgata flaviceps: uncovering the complexity of toxins from the Malayan blue coral snake. J Venom Anim Toxins Incl Trop Dis 2021; 27:e20210024. [PMID: 34616441 PMCID: PMC8476087 DOI: 10.1590/1678-9199-jvatitd-2021-0024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 05/12/2021] [Indexed: 03/03/2023] Open
Abstract
Background: The Malayan blue coral snake, Calliophis bivirgata
flaviceps, is a medically important venomous snake in Southeast
Asia. However, the complexity and diversity of its venom genes remain little
explored. Methods: To address this, we applied high-throughput next-generation sequencing to
profile the venom gland cDNA libraries of C. bivirgata
flaviceps. The transcriptome was de novo
assembled, followed by gene annotation, multiple sequence alignment and
analyses of the transcripts. Results: A total of 74 non-redundant toxin-encoding genes from 16 protein families
were identified, with 31 full-length toxin transcripts. Three-finger toxins
(3FTx), primarily delta-neurotoxins and cardiotoxin-like/cytotoxin-like
proteins, were the most diverse and abundantly expressed. The major 3FTx
(Cb_FTX01 and Cb_FTX02) are highly similar to calliotoxin, a
delta-neurotoxin previously reported in the venom of C.
bivirgata. This study also revealed a conserved tyrosine
residue at position 4 of the cardiotoxin-like/cytotoxin-like protein genes
in the species. These variants, proposed as Y-type CTX-like proteins, are
similar to the H-type CTX from cobras. The substitution is conservative
though, preserving a less toxic form of elapid CTX-like protein, as
indicated by the lack of venom cytotoxicity in previous laboratory and
clinical findings. The ecological role of these toxins, however, remains
unclear. The study also uncovered unique transcripts that belong to
phospholipase A2 of Groups IA and IB, and snake venom
metalloproteinases of PIII subclass, which show sequence variations from
those of Asiatic elapids. Conclusion: The venom gland transcriptome of C. bivirgata flaviceps from
Malaysia was de novo assembled and annotated. The diversity
and expression profile of toxin genes provide insights into the biological
and medical importance of the species.
Collapse
Affiliation(s)
- Praneetha Palasuberniam
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya. Kuala Lumpur, Malaysia.,Department of Biomedical Sciences, University Malaysia Sabah, Faculty of Medicine and Health Sciences, Kota Kinabalu, Sabah, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya. Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya. Kuala Lumpur, Malaysia
| |
Collapse
|
20
|
Yong MY, Tan KY, Tan CH. Potential para-specific and geographical utility of Thai Green Pit Viper (Trimeresurus albolabris) Monovalent Antivenom: Neutralization of procoagulant and hemorrhagic activities of diverse Trimeresurus pit viper venoms. Toxicon 2021; 203:85-92. [PMID: 34600909 DOI: 10.1016/j.toxicon.2021.09.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 09/01/2021] [Accepted: 09/22/2021] [Indexed: 11/29/2022]
Abstract
The Trimeresurus complex consists of diverse medically important venomous pit vipers that cause snakebite envenomation. Antivenoms, however, are in limited supply, and are specific to only two out of the many species across Asia. This study thus investigated the immunoreactivities of regional pit viper antivenoms toward selected Trimeresurus pit viper venoms, and examined the neutralization of their hemotoxic activities. Trimeresurus albolabris Monovalent Antivenom (TaMAV, Thailand) exhibited a higher immunoreactivity than Hemato Bivalent Antivenom (HBAV, raised against Trimeresurus stejnegeri and Protobothrops mucrosquamatus, Taiwan) and Gloydius brevicaudus Monovalent Antivenom (GbMAV, China), attributed to its monovalent nature and conserved antigens in the Trimeresurus pit viper venoms. The venoms showed moderate-to-strong in vitro procoagulant and in vivo hemorrhagic effects consistent with hemotoxic envenomation, except for the Sri Lankan Trimeresurus trigonocephalus venom which lacked hemorrhagic activity. TaMAV was able to differentially neutralize both in vitro and in vivo hemotoxic effects of the venoms, with the lowest efficacy shown against the procoagulant effect of T. trigonocephalus venom. The findings suggest that TaMAV is a potentially useful treatment for envenomation caused by hetero-specific Trimeresurus pit vipers, in particular those in Southeast Asia and East Asia. Clinical study is warranted to establish its spectrum of para-specific effectiveness, and dosages need be tailored to the different species in respective regions.
Collapse
Affiliation(s)
- Mun Yee Yong
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| |
Collapse
|
21
|
Oh AMF, Tan KY, Tan NH, Tan CH. Proteomics and neutralization of Bungarus multicinctus (Many-banded Krait) venom: Intra-specific comparisons between specimens from China and Taiwan. Comp Biochem Physiol C Toxicol Pharmacol 2021; 247:109063. [PMID: 33910092 DOI: 10.1016/j.cbpc.2021.109063] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/12/2021] [Accepted: 04/18/2021] [Indexed: 12/15/2022]
Abstract
The Many-banded Krait (Bungarus multicinctus) is a medically important venomous snake in East Asia. This study investigated the venom proteomes of B. multicinctus from Guangdong, southern China (BM-China) and insular Taiwan (BM-Taiwan), and the neutralization activities of two antivenom products (produced separately in China and Taiwan) against the lethal effect of the venoms. The venom proteomes of both specimens contained similar toxin families, notwithstanding small variations in the subtypes and abundances of minor components. More than 90% of the total venom proteins belong to three-finger toxins (3FTx, including alpha-neurotoxins) and phospholipases A2 (PLA2, including beta-bungarotoxins), supporting their key involvement in the pathophysiology of krait envenomation which manifests as pre- and post-synaptic neurotoxicity. The venoms exhibited potent neurotoxic and lethal effects with extremely low i.v. LD50 of 0.027 μg/g (Bm-China) and 0.087 μg/g (Bm-Taiwan), respectively, in mice. Bungarus multicinctus monovalent antivenom (BMMAV) produced in China and Neuro bivalent antivenom (NBAV) produced in Taiwan were immunoreactive toward both venoms and their toxin fractions. The antivenoms neutralized the venom lethality variably, with BMMAV being more efficacious than NBAV by approximately two-fold. Findings suggest that the monovalent antivenom has a higher potency presumably due to its species-specificity toward the krait venom.
Collapse
Affiliation(s)
- Angeline Mei Feng Oh
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Nget Hong Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| |
Collapse
|
22
|
Wong KY, Tan KY, Tan NH, Gnanathasan CA, Tan CH. Elucidating the Venom Diversity in Sri Lankan Spectacled Cobra ( Naja naja) through De Novo Venom Gland Transcriptomics, Venom Proteomics and Toxicity Neutralization. Toxins (Basel) 2021; 13:558. [PMID: 34437429 PMCID: PMC8402536 DOI: 10.3390/toxins13080558] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/01/2021] [Accepted: 08/05/2021] [Indexed: 01/18/2023] Open
Abstract
Inadequate effectiveness of Indian antivenoms in treating envenomation caused by the Spectacled Cobra/Indian Cobra (Naja naja) in Sri Lanka has been attributed to geographical variations in the venom composition. This study investigated the de novo venom-gland transcriptomics and venom proteomics of the Sri Lankan N. naja (NN-SL) to elucidate its toxin gene diversity and venom variability. The neutralization efficacy of a commonly used Indian antivenom product in Sri Lanka was examined against the lethality induced by NN-SL venom in mice. The transcriptomic study revealed high expression of 22 toxin genes families in NN-SL, constituting 46.55% of total transcript abundance. Three-finger toxins (3FTX) were the most diversely and abundantly expressed (87.54% of toxin gene expression), consistent with the dominance of 3FTX in the venom proteome (72.19% of total venom proteins). The 3FTX were predominantly S-type cytotoxins/cardiotoxins (CTX) and α-neurotoxins of long-chain or short-chain subtypes (α-NTX). CTX and α-NTX are implicated in local tissue necrosis and fatal neuromuscular paralysis, respectively, in envenomation caused by NN-SL. Intra-species variations in the toxin gene sequences and expression levels were apparent between NN-SL and other geographical specimens of N. naja, suggesting potential antigenic diversity that impacts antivenom effectiveness. This was demonstrated by limited potency (0.74 mg venom/ml antivenom) of the Indian polyvalent antivenom (VPAV) in neutralizing the NN-SL venom. A pan-regional antivenom with improved efficacy to treat N. naja envenomation is needed.
Collapse
Affiliation(s)
- Kin Ying Wong
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
| | - Nget Hong Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
| | | | - Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
| |
Collapse
|
23
|
Tan CH, Palasuberniam P, Tan KY. Snake Venom Proteomics, Immunoreactivity and Toxicity Neutralization Studies for the Asiatic Mountain Pit Vipers, Ovophis convictus, Ovophis tonkinensis, and Hime Habu, Ovophis okinavensis. Toxins (Basel) 2021; 13:toxins13080514. [PMID: 34437385 PMCID: PMC8402492 DOI: 10.3390/toxins13080514] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/16/2021] [Accepted: 07/19/2021] [Indexed: 01/01/2023] Open
Abstract
Snakebite envenomation is a serious neglected tropical disease, and its management is often complicated by the diversity of snake venoms. In Asia, pit vipers of the Ovophis species complex are medically important venomous snakes whose venom properties have not been investigated in depth. This study characterized the venom proteomes of Ovophis convictus (West Malaysia), Ovophis tonkinensis (northern Vietnam, southern China), and Ovophis okinavensis (Okinawa, Japan) by applying liquid chromatography-tandem mass spectrometry, which detected a high abundance of snake venom serine proteases (SVSP, constituting 40–60% of total venom proteins), followed by phospholipases A2, snake venom metalloproteinases of mainly P-III class, L-amino acid oxidases, and toxins from other protein families which were less abundant. The venoms exhibited different procoagulant activities in human plasma, with potency decreasing from O. tonkinensis > O. okinavensis > O. convictus. The procoagulant nature of venom confirms that consumptive coagulopathy underlies the pathophysiology of Ovophis pit viper envenomation. The hetero-specific antivenoms Gloydius brevicaudus monovalent antivenom (GbMAV) and Trimeresurus albolabris monovalent antivenom (TaMAV) were immunoreactive toward the venoms, and cross-neutralized their procoagulant activities, albeit at variably limited efficacy. In the absence of species-specific antivenom, these hetero-specific antivenoms may be useful in treating coagulotoxic envenomation caused by the different snakes in their respective regions.
Collapse
Affiliation(s)
- Choo Hock Tan
- Venom Research, Toxicology Research Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
- Correspondence: (C.H.T.); (K.Y.T.)
| | - Praneetha Palasuberniam
- Venom Research, Toxicology Research Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University Malaysia Sabah, Kota Kinabalu 88400, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Lab, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
- Correspondence: (C.H.T.); (K.Y.T.)
| |
Collapse
|
24
|
Lee LP, Tan KY, Tan CH. Snake venom proteomics and antivenomics of two Sundaic lance-headed pit vipers: Trimeresurus wiroti (Malaysia) and Trimeresurus puniceus (Indonesia). Comp Biochem Physiol Part D Genomics Proteomics 2021; 40:100875. [PMID: 34311411 DOI: 10.1016/j.cbd.2021.100875] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 06/28/2021] [Accepted: 06/28/2021] [Indexed: 12/16/2022]
Abstract
Envenomation by two medically important Sundaic pit vipers, Trimeresurus wiroti (Malaysia) and Trimeresurus puniceus (Indonesia), causes hemotoxic syndrome with a potentially fatal outcome. Research on the compositions and antigenicity of these pit viper venoms is however lacking, limiting our understanding of the pathophysiology and treatment of envenomation. This study investigated the venom proteomes of both species through a protein decomplexation strategy, applying C18 reverse-phase high-performance liquid chromatography followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and protein identification through nano-electrospray ionization liquid chromatography-tandem mass spectrometry (nano-ESI-LCMS/MS) of trypsin-digested peptides. The venom antigenicity was profiled against the Thai Green Pit Viper Antivenom (GPVAV, a hetero-specific antivenom), using indirect enzyme-linked immunosorbent assay (ELISA). The venom proteomes of T. wiroti and T. puniceus consisted of 10 and 12 toxin families, respectively. The major proteins were of diverse snake venom serine proteases (19-30% of total venom proteins), snake venom metalloproteinases (17-26%), disintegrins (9-16%), phospholipases A2 (8-28%) and C-type lectins (~8%). These were putative snake toxins implicated in hemorrhage and coagulopathy, consistent with clinical hemotoxicity. GPVAV showed strong immunorecognition toward high and medium molecular weight proteins (e.g., SVMP and PLA2) in both venoms, while a lower binding activity was observed toward small proteins such as disintegrins. Conserved antigenicity in the major hemotoxins supported toxicity cross-neutralization by GPVAV and indicated that the immunorecognition of low molecular weight toxins may be optimized for improved binding efficacy. Taken together, the study provides insights into the pathophysiology and antivenom treatment of envenomation caused by T. wiroti and T. puniceus in the region.
Collapse
Affiliation(s)
- Louisa Pernee Lee
- Venom Research & Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Choo Hock Tan
- Venom Research & Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| |
Collapse
|
25
|
Tan CH, Palasuberniam P, Blanco FB, Tan KY. Immunoreactivity and neutralization capacity of Philippine cobra antivenom against Naja philippinensis and Naja samarensis venoms. Trans R Soc Trop Med Hyg 2021; 115:78-84. [PMID: 32945886 DOI: 10.1093/trstmh/traa087] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 07/25/2020] [Accepted: 08/28/2020] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The Philippine cobra (Naja philippinensis) and Samar cobra (Naja samarensis) are two WHO Category 1 medically important venomous snakes in the Philippines. Philippine cobra antivenom (PCAV) is the only antivenom available in the country, but its neutralization capacity against the venoms of N. philippinensis and hetero-specific N. samarensis has not been reported. This knowledge gap greatly hinders the optimization of antivenom use in the region. METHODS This study examined the immunological binding and neutralization capacity of PCAV against the two cobra venoms using WHO-recommended protocols. RESULTS In mice, both venoms were highly neurotoxic and lethal with a median lethal dose of 0.18 and 0.20 µg/g, respectively. PCAV exhibited strong and comparable immunoreactivity toward the venoms, indicating conserved venom antigenicity between the two allopatric species. In in vivo assay, PCAV was only moderately effective in neutralizing the toxicity of both venoms. Its potency was even lower against the hetero-specific N. samarensis venom by approximately two-fold compared with its potency against N. philippinensis venom. CONCLUSION The results indicated that PCAV could be used to treat N. samarensis envenomation but at a higher dose, which might increase the risk of hypersensitivity and worsen the shortage of antivenom supply in the field. Antivenom manufacturing should be improved by developing a low-dose, high-efficacy product against cobra envenomation.
Collapse
Affiliation(s)
- Choo Hock Tan
- Venom Research & Toxicology Research Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Praneetha Palasuberniam
- Venom Research & Toxicology Research Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.,Department of Biomedical Sciences & Therapeutics, Faculty of Medicine & Health Sciences, University Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia
| | - Francis Bonn Blanco
- Department of Emergency Medicine, Ospital ng Muntinlupa, Manila, The Philippinies.,Department of Emergency Medicine, Eastern Visayas Regional Medical Center, Tacloban, The Philippines
| | - Kae Yi Tan
- Protein and Interactomics Lab, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
26
|
Faisal T, Tan KY, Tan NH, Sim SM, Gnanathasan CA, Tan CH. Proteomics, toxicity and antivenom neutralization of Sri Lankan and Indian Russell's viper ( Daboia russelii) venoms. J Venom Anim Toxins Incl Trop Dis 2021; 27:e20200177. [PMID: 33995514 PMCID: PMC8092856 DOI: 10.1590/1678-9199-jvatitd-2020-0177] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/17/2021] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND The western Russell's viper (Daboia russelii) is widely distributed in South Asia, and geographical venom variation is anticipated among distant populations. Antivenoms used for Russell's viper envenomation are, however, raised typically against snakes from Southern India. The present study investigated and compared the venom proteomes of D. russelii from Sri Lanka (DrSL) and India (DrI), the immunorecognition of Indian VINS Polyvalent Antivenom (VPAV) and its efficacy in neutralizing the venom toxicity. METHODS The venoms of DrSL and DrI were decomplexed with C18 high-performance liquid chromatography and SDS-polyacrylamide gel electrophoresis under reducing conditions. The proteins fractionated were identified through nano-ESI-liquid chromatography-tandem mass spectrometry (LCMS/MS). The immunological studies were conducted with enzyme-linked immunosorbent assay. The neutralization of the venom procoagulant effect was evaluated in citrated human plasma. The neutralization of the venom lethality was assessed in vivo in mice adopting the WHO protocol. RESULTS DrSL and DrI venom proteomes showed comparable major protein families, with phospholipases A2 (PLA2) being the most abundant (> 60% of total venom proteins) and diverse (six protein forms identified). Both venoms were highly procoagulant and lethal (intravenous median lethal dose in mice, LD50 = 0.24 and 0.32 µg/g, for DrSL and DrI, respectively), while lacking hemorrhagic and anticoagulant activities. VPAV was immunoreactive toward DrSL and DrI venoms, indicating conserved protein antigenicity in the venoms. The high molecular weight venom proteins were, however, more effectively immunorecognized than small ones. VPAV was able to neutralize the coagulopathic and lethal effects of the venoms moderately. CONCLUSION Considering that a large amount of venom can be injected by Russell's viper during envenomation, the potency of antivenom can be further improved for optimal neutralization and effective treatment. Region-specific venoms and key toxins may be incorporated into the immunization procedure during antivenom production.
Collapse
Affiliation(s)
- Tasnim Faisal
- Department of Pharmacology, Faculty of Medicine, University of
Malaya, Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, University of
Malaya, Kuala Lumpur, Malaysia
| | - Nget Hong Tan
- Department of Molecular Medicine, Faculty of Medicine, University of
Malaya, Kuala Lumpur, Malaysia
| | - Si Mui Sim
- Department of Pharmacology, Faculty of Medicine, University of
Malaya, Kuala Lumpur, Malaysia
| | | | - Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, University of
Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
27
|
Tan CH, Tan KY. De Novo Venom-Gland Transcriptomics of Spine-Bellied Sea Snake ( Hydrophis curtus) from Penang, Malaysia-Next-Generation Sequencing, Functional Annotation and Toxinological Correlation. Toxins (Basel) 2021; 13:toxins13020127. [PMID: 33572266 PMCID: PMC7915529 DOI: 10.3390/toxins13020127] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/31/2021] [Accepted: 02/02/2021] [Indexed: 01/26/2023] Open
Abstract
Envenomation resulted from sea snake bite is a highly lethal health hazard in Southeast Asia. Although commonly caused by sea snakes of Hydrophiinae, each species is evolutionarily distinct and thus, unveiling the toxin gene diversity within individual species is important. Applying next-generation sequencing, this study investigated the venom-gland transcriptome of Hydrophis curtus (spine-bellied sea snake) from Penang, West Malaysia. The transcriptome was de novo assembled, followed by gene annotation and sequence analyses. Transcripts with toxin annotation were only 96 in number but highly expressed, constituting 48.18% of total FPKM in the overall transcriptome. Of the 21 toxin families, three-finger toxins (3FTX) were the most abundantly expressed and functionally diverse, followed by phospholipases A2. Lh_FTX001 (short neurotoxin) and Lh_FTX013 (long neurotoxin) were the most dominant 3FTXs expressed, consistent with the pathophysiology of envenomation. Lh_FTX001 and Lh_FTX013 were variable in amino acid compositions and predicted epitopes, while Lh_FTX001 showed high sequence similarity with the short neurotoxin from Hydrophis schistosus, supporting cross-neutralization effect of Sea Snake Antivenom. Other toxins of low gene expression, for example, snake venom metalloproteinases and L-amino acid oxidases not commonly studied in sea snake venom were also identified, enriching the knowledgebase of sea snake toxins for future study.
Collapse
Affiliation(s)
- Choo Hock Tan
- Venom Research and Toxicoogy Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
- Correspondence:
| | - Kae Yi Tan
- Protein and Interactomics Lab, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
| |
Collapse
|
28
|
Wong KY, Tan KY, Tan NH, Tan CH. A Neurotoxic Snake Venom without Phospholipase A 2: Proteomics and Cross-Neutralization of the Venom from Senegalese Cobra, Naja senegalensis (Subgenus: Uraeus). Toxins (Basel) 2021; 13:toxins13010060. [PMID: 33466660 PMCID: PMC7828783 DOI: 10.3390/toxins13010060] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/22/2020] [Accepted: 01/07/2021] [Indexed: 11/16/2022] Open
Abstract
The Senegalese cobra, Naja senegalensis, is a non-spitting cobra species newly erected from the Naja haje complex. Naja senegalensis causes neurotoxic envenomation in Western Africa but its venom properties remain underexplored. Applying a protein decomplexation proteomic approach, this study unveiled the unique complexity of the venom composition. Three-finger toxins constituted the major component, accounting for 75.91% of total venom proteins. Of these, cardiotoxin/cytotoxin (~53%) and alpha-neurotoxins (~23%) predominated in the venom proteome. Phospholipase A2, however, was not present in the venom, suggesting a unique snake venom phenotype found in this species. The venom, despite the absence of PLA2, is highly lethal with an intravenous LD50 of 0.39 µg/g in mice, consistent with the high abundance of alpha-neurotoxins (predominating long neurotoxins) in the venom. The hetero-specific VINS African Polyvalent Antivenom (VAPAV) was immunoreactive to the venom, implying conserved protein antigenicity in the venoms of N. senegalensis and N. haje. Furthermore, VAPAV was able to cross-neutralize the lethal effect of N. senegalensis venom but the potency was limited (0.59 mg venom completely neutralized per mL antivenom, or ~82 LD50 per ml of antivenom). The efficacy of antivenom should be further improved to optimize the treatment of cobra bite envenomation in Africa.
Collapse
Affiliation(s)
- Kin Ying Wong
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
| | - Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (K.Y.T.); (N.H.T.)
| | - Nget Hong Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (K.Y.T.); (N.H.T.)
| | - Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
- Correspondence: ; Tel.: +60-3-7967-6685
| |
Collapse
|
29
|
Tan CH, Bourges A, Tan KY. King Cobra and snakebite envenomation: on the natural history, human-snake relationship and medical importance of Ophiophagus hannah. J Venom Anim Toxins Incl Trop Dis 2021; 27:e20210051. [PMID: 35069710 PMCID: PMC8733962 DOI: 10.1590/1678-9199-jvatitd-2021-0051] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 06/25/2021] [Indexed: 01/28/2023] Open
Abstract
King Cobra (Ophiophagus hannah) has a significant place in many
cultures, and is a medically important venomous snake in the world. Envenomation
by this snake is highly lethal, manifested mainly by neurotoxicity and local
tissue damage. King Cobra may be part of a larger species complex, and is widely
distributed across Southeast Asia, southern China, northern and eastern regions
as well as the Western Ghats of India, indicating potential geographical
variation in venom composition. There is, however, only one species-specific
King Cobra antivenom available worldwide that is produced in Thailand, using
venom from the snake of Thai origin. Issues relating to the management of King
Cobra envenomation (e.g., variation in the composition and
toxicity of the venom, limited availability and efficacy of antivenom), and
challenges faced in the research of venom (in particular proteomics), are rarely
addressed. This article reviews the natural history and sociocultural importance
of King Cobra, cases of snakebite envenomation caused by this species, current
practice of management (preclinical and clinical), and major toxinological
studies of the venom with a focus on venom proteomics, toxicity and
neutralization. Unfortunately, epidemiological data of King Cobra bite is
scarce, and venom proteomes reported in various studies revealed marked
discrepancies in details. Challenges, such as inconsistency in snake venom
sampling, varying methodology of proteomic analysis, lack of mechanistic and
antivenomic studies, and controversy surrounding antivenom use in treating King
Cobra envenomation are herein discussed. Future directions are proposed,
including the effort to establish a standard, comprehensive Pan-Asian proteomic
database of King Cobra venom, from which the venom variation can be determined.
Research should be undertaken to characterize the toxin antigenicity, and to
develop an antivenom with improved efficacy and wider geographical utility. The
endeavors are aligned with the WHO´s roadmap that aims to reduce the disease
burden of snakebite by 50% before 2030.
Collapse
Affiliation(s)
| | - Aymeric Bourges
- University of Malaya, Malaysia; Université Libre de Bruxelles, Belgium
| | | |
Collapse
|
30
|
Chong HP, Tan KY, Tan CH. Cytotoxicity of Snake Venoms and Cytotoxins From Two Southeast Asian Cobras ( Naja sumatrana, Naja kaouthia): Exploration of Anticancer Potential, Selectivity, and Cell Death Mechanism. Front Mol Biosci 2020; 7:583587. [PMID: 33263003 PMCID: PMC7686564 DOI: 10.3389/fmolb.2020.583587] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/25/2020] [Indexed: 01/09/2023] Open
Abstract
Venoms of cobras (Naja spp.) contain high abundances of cytotoxins, which contribute to tissue necrosis in cobra envenomation. The tissue-necrotizing activity of cobra cytotoxins, nevertheless, indicates anticancer potentials. This study set to explore the anticancer properties of the venoms and cytotoxins from Naja sumatrana (equatorial spitting cobra) and Naja kaouthia (monocled cobra), two highly venomous species in Southeast Asia. The cytotoxicity, selectivity, and cell death mechanisms of their venoms and cytotoxins (NS-CTX from N. sumatrana: NS-CTX; N. kaouthia: NK-CTX) were elucidated in human lung (A549), prostate (PC-3), and breast (MCF-7) cancer cell lines. Cytotoxins were purified through a sequential fractionation approach using cation-exchange chromatography, followed by C18 reverse-phase high-performance liquid chromatography (HPLC) to homogeneity validated with sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and identified by liquid chromatography-tandem mass spectrometry (LCMS/MS). The cobra venoms and their respective cytotoxins exhibited concentration-dependent growth inhibitory effects in all cell lines tested, with the cytotoxins being more potent compared to the corresponding whole venoms. NS-CTX and NK-CTX are, respectively, P-type and S-type isoforms of cytotoxin, based on the amino acid sequences as per LCMS/MS analysis. Both cytotoxins exhibited differential cytotoxic effects in the cell lines tested, with NS-CTX (P-type cytotoxin) being significantly more potent in inhibiting the growth of the cancer cells. Both cytotoxins demonstrated promising selectivity only for the A549 lung cancer cell line (selectivity index = 2.17 and 2.26, respectively) but not in prostate (PC-3) and breast (MCF-7) cancer cell lines (selectivity index < 1). Flow cytometry revealed that the A549 lung cancer cells treated with NS-CTX and NK-CTX underwent necrosis predominantly. Meanwhile, the cytotoxins induced mainly caspase-independent late apoptosis in the prostate (PC-3) and breast (MCF-7) cancer cells lines but lacked selectivity. The findings revealed the limitations and challenges that could be faced during the development of new cancer therapy from cobra cytotoxins, notwithstanding their potent anticancer effects. Further studies should aim to overcome these impediments to unleash the anticancer potentials of the cytotoxins.
Collapse
Affiliation(s)
- Ho Phin Chong
- Venom Research and Toxicology Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Lab, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Venom Research and Toxicology Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
31
|
Tan CH, Liew JL, Navanesan S, Sim KS, Tan NH, Tan KY. Cytotoxic and anticancer properties of the Malaysian mangrove pit viper ( Trimeresurus purpureomaculatus) venom and its disintegrin (purpureomaculin). J Venom Anim Toxins Incl Trop Dis 2020; 26:e20200013. [PMID: 32742279 PMCID: PMC7375409 DOI: 10.1590/1678-9199-jvatitd-2020-0013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 05/29/2020] [Indexed: 11/22/2022] Open
Abstract
Background The Asiatic pit vipers from the Trimeresurus complex are medically important venomous snakes. These pit vipers are often associated with snakebite that leads to fatal coagulopathy and tissue necrosis. The cytotoxic venoms of Trimeresurus spp.; however, hold great potential for the development of peptide-based anticancer drugs. Methods This study investigated the cytotoxic effect of the venom from Trimeresurus purpureomaculatus, the mangrove pit viper (also known as shore pit viper) which is native in Malaysia, across a panel of human cancer cell lines from breast, lung, colon and prostate as well as the corresponding normal cell lines of each tissue. Results The venom exhibited dose-dependent cytotoxic activities on all cell lines tested, with median inhibition concentrations (IC50) ranging from 0.42 to 6.98 µg/mL. The venom has a high selectivity index (SI = 14.54) on breast cancer cell line (MCF7), indicating that it is significantly more cytotoxic toward the cancer than to normal cell lines. Furthermore, the venom was fractionated using C18 reversed-phase high-performance liquid chromatography and the anticancer effect of each protein fraction was examined. Fraction 1 that contains a hydrophilic low molecular weight (approximately 7.5 kDa) protein was found to be the most cytotoxic and selective toward the breast cancer cell line (MCF7). The protein was identified using liquid chromatography-tandem mass spectrometry as a venom disintegrin, termed purpureomaculin in this study. Conclusion Taken together, the findings revealed the potent and selective cytotoxicity of a disintegrin protein isolated from the Malaysian T. purpureomaculatus venom and suggested its anticancer potential in drug discovery.
Collapse
Affiliation(s)
- Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Jia Lee Liew
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Suerialoasan Navanesan
- Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Kae Shin Sim
- Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Nget Hong Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
32
|
Pruksaphon K, Tan KY, Tan CH, Simsiriwong P, Gutiérrez JM, Ratanabanangkoon K. An in vitro α-neurotoxin-nAChR binding assay correlates with lethality and in vivo neutralization of a large number of elapid neurotoxic snake venoms from four continents. PLoS Negl Trop Dis 2020; 14:e0008581. [PMID: 32857757 PMCID: PMC7535858 DOI: 10.1371/journal.pntd.0008581] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 10/05/2020] [Accepted: 07/09/2020] [Indexed: 11/25/2022] Open
Abstract
The aim of this study was to develop an in vitro assay for use in place of in vivo assays of snake venom lethality and antivenom neutralizing potency. A novel in vitro assay has been developed based on the binding of post-synaptically acting α-neurotoxins to nicotinic acetylcholine receptor (nAChR), and the ability of antivenoms to prevent this binding. The assay gave high correlation in previous studies with the in vivo murine lethality tests (Median Lethal Dose, LD50), and the neutralization of lethality assays (Median Effective Dose, ED50) by antisera against Naja kaouthia, Naja naja and Bungarus candidus venoms. Here we show that, for the neurotoxic venoms of 20 elapid snake species from eight genera and four continents, the in vitro median inhibitory concentrations (IC50s) for α-neurotoxin binding to purified nAChR correlated well with the in vivo LD50s of the venoms (R2 = 0.8526, p < 0.001). Furthermore, using this assay, the in vitro ED50s of a horse pan-specific antiserum against these venoms correlated significantly with the corresponding in vivo murine ED50s, with R2 = 0.6896 (p < 0.01). In the case of four elapid venoms devoid or having a very low concentration of α-neurotoxins, no inhibition of nAChR binding was observed. Within the philosophy of 3Rs (Replacement, Reduction and Refinement) in animal testing, the in vitro α-neurotoxin-nAChR binding assay can effectively substitute the mouse lethality test for toxicity and antivenom potency evaluation for neurotoxic venoms in which α-neurotoxins predominate. This will greatly reduce the number of mice used in toxicological research and antivenom production laboratories. The simpler, faster, cheaper and less variable in vitro assay should also expedite the development of pan-specific antivenoms against various medically important snakes in many parts of the world.
Collapse
Affiliation(s)
- Kritsada Pruksaphon
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | | | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Kavi Ratanabanangkoon
- Laboratory of Immunology, Chulabhorn Research Institute, Bangkok, Thailand
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| |
Collapse
|
33
|
Ratanabanangkoon K, Tan KY, Pruksaphon K, Klinpayom C, Gutiérrez JM, Quraishi NH, Tan CH. A pan-specific antiserum produced by a novel immunization strategy shows a high spectrum of neutralization against neurotoxic snake venoms. Sci Rep 2020; 10:11261. [PMID: 32647261 PMCID: PMC7347863 DOI: 10.1038/s41598-020-66657-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Accepted: 04/30/2020] [Indexed: 11/17/2022] Open
Abstract
Snakebite envenomation is a neglected tropical disease of high mortality and morbidity largely due to insufficient supply of effective and affordable antivenoms. Snake antivenoms are mostly effective against the venoms used in their production. It is thus crucial that effective and affordable antivenom(s) with wide para-specificity, capable of neutralizing the venoms of a large number of snakes, be produced. Here we studied the pan-specific antiserum prepared previously by a novel immunization strategy involving the exposure of horses to a ‘diverse toxin repertoire’ consisting of 12 neurotoxic Asian snake toxin fractions/ venoms from six species. This antiserum was previously shown to exhibit wide para-specificity by neutralizing 11 homologous and 16 heterologous venoms from Asia and Africa. We now show that the antiserum can neutralize 9 out of 10 additional neurotoxic venoms. Altogether, 36 snake venoms belonging to 10 genera from 4 continents were neutralized by the antiserum. Toxin profiles previously generated using proteomic techniques of these 36 venoms identified α-neurotoxins, β-neurotoxins, and cytotoxins as predominant toxins presumably neutralized by the antiserum. The bases for the wide para-specificity of the antiserum are discussed. These findings indicate that it is feasible to generate antivenoms of wide para-specificity against elapid neurotoxic venoms from different regions in the world and raises the possibility of a universal neurotoxic antivenom. This should reduce the mortality resulting from neurotoxic snakebite envenomation.
Collapse
Affiliation(s)
- Kavi Ratanabanangkoon
- Department of Microbiology, Faculty of Science, Mahidol University, Rama 6 Road, Bangkok, 10400, Thailand. .,Laboratory of Immunology, Chulabhorn Research Institute, Bangkok, 10210, Thailand.
| | - Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia
| | - Kritsada Pruksaphon
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Chaiya Klinpayom
- Veterinary Hospital, The Veterinary and Remount Department, The Royal Thai Army, Nakorn Pathom, 73000, Thailand
| | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Naeem H Quraishi
- Anti Snake Venom/Anti Rabies Serology Laboratory, People's University of Medical and Health Sciences for Women, Nawabshah, Pakistan
| | - Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia.
| |
Collapse
|
34
|
Hia YL, Tan KY, Tan CH. Comparative venom proteomics of banded krait (Bungarus fasciatus) from five geographical locales: Correlation of venom lethality, immunoreactivity and antivenom neutralization. Acta Trop 2020; 207:105460. [PMID: 32278639 DOI: 10.1016/j.actatropica.2020.105460] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 03/25/2020] [Indexed: 10/24/2022]
Abstract
The banded krait, Bungarus fasciatus is a medically important venomous snake in Asia. The wide distribution of this species in Southeast Asia and southern China indicates potential geographical variation of the venom which may impact the clinical management of snakebite envenomation. This study investigated the intraspecific venom variation of B. fasciatus from five geographical locales through a venom decomplexing proteomic approach, followed by toxinological and immunological studies. The venom proteomes composed of a total of 9 toxin families, comprising 22 to 31 proteoforms at varying abundances. The predominant proteins were phospholipase A2 (including beta-bungarotoxin), Kunitz-type serine protease inhibitor (KSPI) and three-finger toxins (3FTx), which are toxins that cause neurotoxicity and lethality. The venom lethality varied with geographical origins of the snake, with intravenous median lethal doses (LD50) ranging from 0.45-2.55 µg/g in mice. The Thai Bungarus fasciatus monovalent antivenom (BFMAV) demonstrated a dose-dependent increasing immunological binding activity toward all venoms; however, its in vivo neutralization efficacy varied vastly with normalized potency values ranging from 3 to 28 mg/g, presumably due to the compositional differences of dominant proteins in the different venoms. The findings support that antivenom use should be optimized in different geographical areas. The development of a pan-regional antivenom may be a more sustainable solution for the treatment of snakebite envenomation.
Collapse
|
35
|
Tan KY, Wong KY, Tan NH, Tan CH. Quantitative proteomics of Naja annulifera (sub-Saharan snouted cobra) venom and neutralization activities of two antivenoms in Africa. Int J Biol Macromol 2020; 158:S0141-8130(20)33035-X. [PMID: 32339578 DOI: 10.1016/j.ijbiomac.2020.04.173] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 04/18/2020] [Accepted: 04/21/2020] [Indexed: 12/27/2022]
Abstract
Envenomation by Naja annulifera (snouted cobra), a non-spitting African cobra, can result in local tissue damage and fatal paralysis but a species-specific antivenom treatment is currently lacking. In this study, we investigated the quantitative proteome of N. annulifera venom, incorporating HPLC and LC-MS/MS to elucidate the venom toxicity. The immunoreactivities and in vivo neutralization activities of two hetero-specific antivenom products (Premium Serums Pan Africa polyvalent antivenom, PANAF and VINS African polyvalent antivenom, VAPAV) against the venom were subsequently examined. N. annulifera venom comprises 10 toxin families, with three-finger toxin (3FTx) being the most abundantly expressed (~78%). Within 3FTx, cytotoxin is the most dominant form and made up three-quarter of the venom bulk (~74%), whereas alpha-neurotoxins constitute <4% of the total venom proteins. Phospholipase A2 was undetected in the venom proteome, consistent with the unusual absence of PLA2 from the venoms of cobras in the Uraeus subgenus. In ELISA, PANAF and VAPAV showed comparable immunoreactivity toward the protein antigens of N. annulifera venom. These antivenoms, despite being raised against hetero-specific venoms, were capable of cross-neutralizing the lethal effect of N. annulifera venom in mice, with PANAF being marginally more potent.
Collapse
Affiliation(s)
- Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kin Ying Wong
- Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Nget Hong Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| |
Collapse
|
36
|
Tan CH, Tan KY, Tan NH, Wong KY. Insights into the evolutionary and medical significance of unique alpha-neurotoxin and phospholipase A2 compositions in Naja spp. (cobra) venoms. Toxicon 2020. [DOI: 10.1016/j.toxicon.2019.10.052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
37
|
Tan KY, Ng TS, Bourges A, Ismail AK, Maharani T, Khomvilai S, Sitprija V, Tan NH, Tan CH. Geographical variations in king cobra (Ophiophagus hannah) venom from Thailand, Malaysia, Indonesia and China: On venom lethality, antivenom immunoreactivity and in vivo neutralization. Acta Trop 2020; 203:105311. [PMID: 31862461 DOI: 10.1016/j.actatropica.2019.105311] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 12/16/2019] [Accepted: 12/16/2019] [Indexed: 01/27/2023]
Abstract
The wide distribution of king cobra (Ophiophagus hannah), a medically important venomous snake in Asia could be associated with geographical variation in the toxicity and antigenicity of the venom. This study investigated the lethality of king cobra venoms (KCV) from four geographical locales (Malaysia, Thailand, Indonesia, China), and the immunological binding as well as in vivo neutralization activities of three antivenom products (Thai Ophiophagus hannah monovalent antivenom, OHMAV; Indonesian Serum Anti Bisa Ular, SABU; Chinese Naja atra monovalent antivenom, NAMAV) toward the venoms. The Indonesian and Chinese KCV were more lethal (median lethal dose, LD50 ~0.5 μg/g) than those from Malaysia and Thailand (LD50 ~1.0 μg/g). The antivenoms, composed of F(ab)'2, were variably immunoreactive toward the KCV from all locales, with OHMAV exhibited the highest immunological binding activity. In mice, OHMAV neutralized the neurotoxic lethality of Thai KCV most effectively (normalized potency = 118 mg venom neutralized per g antivenom) followed by Malaysian, Indonesian and Chinese KCV. In comparison, the hetero-specific SABU was remarkably less potent by at least 6 to10 folds, whereas NAMAV appeared to be non-effective. The finding supports that a specific king cobra antivenom is needed for the effective treatment of king cobra envenomation in each region.
Collapse
Affiliation(s)
- Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Tzu Shan Ng
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Aymeric Bourges
- Venom Research & Toxicology Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Ahmad Khaldun Ismail
- Department of Emergency Medicine, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia
| | - Tri Maharani
- Department of Emergency, Daha Husada Hospital, Kediri, East Java Province, Indonesia
| | - Sumana Khomvilai
- Queen Saovabha Memorial Institute, Thai Red Cross Society, Bangkok, Thailand
| | - Visith Sitprija
- Queen Saovabha Memorial Institute, Thai Red Cross Society, Bangkok, Thailand
| | - Nget Hong Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Venom Research & Toxicology Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| |
Collapse
|
38
|
Leon RCC, Yang CH, Hwang JCC, Lemyre JC, Tanttu T, Huang W, Chan KW, Tan KY, Hudson FE, Itoh KM, Morello A, Laucht A, Pioro-Ladrière M, Saraiva A, Dzurak AS. Coherent spin control of s-, p-, d- and f-electrons in a silicon quantum dot. Nat Commun 2020; 11:797. [PMID: 32047151 PMCID: PMC7012832 DOI: 10.1038/s41467-019-14053-w] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 12/11/2019] [Indexed: 11/09/2022] Open
Abstract
Once the periodic properties of elements were unveiled, chemical behaviour could be understood in terms of the valence of atoms. Ideally, this rationale would extend to quantum dots, and quantum computation could be performed by merely controlling the outer-shell electrons of dot-based qubits. Imperfections in semiconductor materials disrupt this analogy, so real devices seldom display a systematic many-electron arrangement. We demonstrate here an electrostatically confined quantum dot that reveals a well defined shell structure. We observe four shells (31 electrons) with multiplicities given by spin and valley degrees of freedom. Various fillings containing a single valence electron-namely 1, 5, 13 and 25 electrons-are found to be potential qubits. An integrated micromagnet allows us to perform electrically-driven spin resonance (EDSR), leading to faster Rabi rotations and higher fidelity single qubit gates at higher shell states. We investigate the impact of orbital excitations on single qubits as a function of the dot deformation and exploit it for faster qubit control.
Collapse
Affiliation(s)
- R C C Leon
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, NSW, 2052, Australia.
| | - C H Yang
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - J C C Hwang
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, NSW, 2052, Australia
- Research and Prototype Foundry, The University of Sydney, Sydney, NSW, 2006, Australia
| | - J Camirand Lemyre
- Institut Quantique et Département de Physique, Université de Sherbrooke, Sherbrooke, Québec, J1K 2R1, Canada
| | - T Tanttu
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - W Huang
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - K W Chan
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - K Y Tan
- QCD Labs COMP Centre of Excellence, Department of Applied Physics, Aalto University, 00076, Aalto, Finland
| | - F E Hudson
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - K M Itoh
- School of Fundamental Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohokuku, Yokohama, 223-8522, Japan
| | - A Morello
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - A Laucht
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - M Pioro-Ladrière
- Institut Quantique et Département de Physique, Université de Sherbrooke, Sherbrooke, Québec, J1K 2R1, Canada
- Quantum Information Science Program, Canadian Institute for Advanced Research, Toronto, ON, M5G 1Z8, Canada
| | - A Saraiva
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, NSW, 2052, Australia.
| | - A S Dzurak
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, NSW, 2052, Australia.
| |
Collapse
|
39
|
Lingam TMC, Tan KY, Tan CH. Proteomics and antivenom immunoprofiling of Russell's viper ( Daboia siamensis) venoms from Thailand and Indonesia. J Venom Anim Toxins Incl Trop Dis 2020; 26:e20190048. [PMID: 32082369 PMCID: PMC7004479 DOI: 10.1590/1678-9199-jvatitd-2019-0048] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Accepted: 11/22/2019] [Indexed: 12/17/2022] Open
Abstract
The Eastern Russell’s viper, Daboia siamensis, is a WHO Category
1 medically important venomous snake. It has a wide but disjunct distribution in
Southeast Asia. The specific antivenom, D. siamensis Monovalent
Antivenom (DsMAV-Thailand) is produced in Thailand but not available in
Indonesia, where a heterologous trivalent antivenom, Serum Anti Bisa Ular
(SABU), is used instead. This study aimed to investigate the geographical venom
variation of D. siamensis from Thailand (Ds-Thailand) and
Indonesia (Ds-Indonesia), and the immunorecognition of the venom proteins by
antivenoms.
Collapse
Affiliation(s)
| | - Kae Yi Tan
- Department of Molecular Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Department of Pharmacology, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
40
|
Zhao R, Tanttu T, Tan KY, Hensen B, Chan KW, Hwang JCC, Leon RCC, Yang CH, Gilbert W, Hudson FE, Itoh KM, Kiselev AA, Ladd TD, Morello A, Laucht A, Dzurak AS. Single-spin qubits in isotopically enriched silicon at low magnetic field. Nat Commun 2019; 10:5500. [PMID: 31796728 PMCID: PMC6890755 DOI: 10.1038/s41467-019-13416-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 11/06/2019] [Indexed: 11/09/2022] Open
Abstract
Single-electron spin qubits employ magnetic fields on the order of 1 Tesla or above to enable quantum state readout via spin-dependent-tunnelling. This requires demanding microwave engineering for coherent spin resonance control, which limits the prospects for large scale multi-qubit systems. Alternatively, singlet-triplet readout enables high-fidelity spin-state measurements in much lower magnetic fields, without the need for reservoirs. Here, we demonstrate low-field operation of metal-oxide-silicon quantum dot qubits by combining coherent single-spin control with high-fidelity, single-shot, Pauli-spin-blockade-based ST readout. We discover that the qubits decohere faster at low magnetic fields with [Formula: see text] μs and [Formula: see text] μs at 150 mT. Their coherence is limited by spin flips of residual 29Si nuclei in the isotopically enriched 28Si host material, which occur more frequently at lower fields. Our finding indicates that new trade-offs will be required to ensure the frequency stabilization of spin qubits, and highlights the importance of isotopic enrichment of device substrates for the realization of a scalable silicon-based quantum processor.
Collapse
Affiliation(s)
- R Zhao
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW, 2052, Australia.
- National Institute of Standards and Technology, 325 Broadway, Boulder, CO, 80305, USA.
| | - T Tanttu
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW, 2052, Australia
| | - K Y Tan
- QCD Labs, QTF Centre of Excellence, Department of Applied Physics, Aalto University, 00076, Aalto, Finland
- IQM Finland Oy, Vaisalantie 6 C, 02130, Espoo, Finland
| | - B Hensen
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW, 2052, Australia
| | - K W Chan
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW, 2052, Australia
| | - J C C Hwang
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW, 2052, Australia
- Research and Prototype Foundry, The University of Sydney, Sydney, NSW, 2006, Australia
| | - R C C Leon
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW, 2052, Australia
| | - C H Yang
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW, 2052, Australia
| | - W Gilbert
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW, 2052, Australia
| | - F E Hudson
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW, 2052, Australia
| | - K M Itoh
- School of Fundamental Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, 223-8522, Japan
| | - A A Kiselev
- HRL Laboratories, LLC, 3011 Malibu Canyon Road, Malibu, CA, 90265, USA
| | - T D Ladd
- HRL Laboratories, LLC, 3011 Malibu Canyon Road, Malibu, CA, 90265, USA
| | - A Morello
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW, 2052, Australia
| | - A Laucht
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW, 2052, Australia
| | - A S Dzurak
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW, 2052, Australia.
| |
Collapse
|
41
|
He C, Lu J, Ong MW, Lee DJK, Tan KY, Chia CLK. Seroma prevention strategies in laparoscopic ventral hernia repair: a systematic review. Hernia 2019; 24:717-731. [PMID: 31784913 DOI: 10.1007/s10029-019-02098-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Accepted: 11/17/2019] [Indexed: 01/01/2023]
Abstract
BACKGROUND Laparoscopic ventral hernia repair (LVHR) has been increasing in popularity over the years. Seroma formation is a common complication of LVHR. The aim of this study is to review the current evidence on seroma prevention strategies following LVHR. METHODS A systematic search of PubMed, Embase (1946-13 February 2019) and Medline (1946-13 February 2019) databases was conducted using terms which include "seroma", "hernia, ventral" and "laparoscopy". All studies are comparative retrospective or prospective human adult studies in peer-reviewed journals describing at least one intra-operative intervention designed to decrease the rate of seroma formation in laparoscopic ventral hernia repair. RESULTS The database searches identified 3762 citations, and 21 studies were included for final analysis. Five studies compared the different methods of mesh fixation, nine studies compared primary defect closure (PFC) and bridged repair, two studies compared the effect of different types of meshes, two studies looked into the use of electrical cauterization, one study compared single- site laparoscopy with conventional laparoscopy, one study looked into the use of fibrin sealant and one study compared transabdominal preperitoneal placement of mesh with conventional repair. PFC appears to be the most promising with large studies showing a low rate of seroma formation with additional benefits of decreasing wound infection and recurrence rate. Cauterisation of hernia sac and injection of fibrin sealant also show promising results but are mainly derived from small studies. Other strategies did not demonstrate benefit. CONCLUSION Currently, primary fascial closure appears to be the most promising strategy available to decrease seroma formation after LVHR based on the results of large studies. Other promising strategies that decrease dead space such as cauterisation of the sac and fibrin sealant injection will require further multicentre trials to confirm benefit before an increase in operative time and cost can be justified for their routine use.
Collapse
Affiliation(s)
- C He
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - J Lu
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - M W Ong
- Department of General Surgery, Khoo Teck Puat Hospital, 90 Yishun Central, Singapore, Singapore
| | - D J K Lee
- Department of General Surgery, Khoo Teck Puat Hospital, 90 Yishun Central, Singapore, Singapore
| | - K Y Tan
- Department of General Surgery, Khoo Teck Puat Hospital, 90 Yishun Central, Singapore, Singapore
| | - C L K Chia
- Department of General Surgery, Khoo Teck Puat Hospital, 90 Yishun Central, Singapore, Singapore.
| |
Collapse
|
42
|
Lingam TMC, Tan KY, Tan CH. Thai Russell's viper monospecific antivenom is immunoreactive and effective in neutralizing the venom of Daboia siamensis from Java, Indonesia. Toxicon 2019; 168:95-97. [DOI: 10.1016/j.toxicon.2019.06.227] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 06/13/2019] [Accepted: 06/25/2019] [Indexed: 11/30/2022]
|
43
|
Tan CH, Wong KY, Chong HP, Tan NH, Tan KY. Proteomic insights into short neurotoxin-driven, highly neurotoxic venom of Philippine cobra (Naja philippinensis) and toxicity correlation of cobra envenomation in Asia. J Proteomics 2019; 206:103418. [PMID: 31201947 DOI: 10.1016/j.jprot.2019.103418] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 05/19/2019] [Accepted: 06/11/2019] [Indexed: 01/07/2023]
Abstract
The Philippine cobra, Naja philippinensis, is a WHO Category 1 venomous snake of medical importance responsible for fatal envenomation in the northern Philippines. To elucidate the venom proteome and pathophysiology of envenomation, N. philippinensis venom proteins were decomplexed with reverse-phase high-performance liquid chromatography, and protein fractions were subsequently digested with trypsin, followed by nano-liquid chromatography-tandem mass spectrometry analysis and data mining. Three-finger toxins (3FTX, 66.64% of total venom proteins) and phospholipases A2 (PLA2, 22.88%) constitute the main bulk of venom proteome. Other proteins are present at low abundances (<4% each); these include metalloproteinase, serine protease, cobra venom factor, cysteine-rich secretory protein, vespryn, phosphodiesterase, 5' nucleotidase and nerve growth factor. In the three-finger toxin family, the alpha-neurotoxins comprise solely short neurotoxins (SNTX, 44.55%), supporting that SNTX is the principal toxin responsible for neuromuscular paralysis and lethality reported in clinical envenomation. Cytotoxins (CTX) are the second most abundant 3FTX proteins in the venom (21.31%). The presence of CTX correlates with the venom cytotoxic effect, which is more prominent in murine cells than in human cells. From the practical standpoint, SNTX-driven neuromuscular paralysis is significant in N. philippinensis envenomation. Antivenom production and treatment should be tailored accordingly to ensure effective neutralization of SNTX. BIOLOGICAL SIGNIFICANCE: The venom proteome of Naja philippinensis, the Philippine cobra, is unravelled for the first time. Approximately half the protein bulk of the venom is made up of short neurotoxins (44.55% of the total venom proteins). As the only alpha-neurotoxins present in the venom, short neurotoxins are the causative toxins of the post-synaptic blockade and fast-onset neuromuscular paralysis in N. philippinensis envenomation. A substantial amount of cytotoxins (21.31%) was also detected in N. philippinensis venom, supporting that the venom can be cytotoxic although the effect is much weaker in human cells compared to murine cells. The finding is consistent with the low incidence of local tissue necrosis in N. philippinensis envenomation, although this does not negate the need for monitoring and care of bite wound in the patients.
Collapse
Affiliation(s)
- Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kin Ying Wong
- Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Ho Phin Chong
- Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Nget Hong Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| |
Collapse
|
44
|
Tan KY, Liew ST, Tan QY, Abdul-Rahman FN, Azmi NI, Sim SM, Tan NH, Khomvilai S, Sitprija V, Tan CH. Evaluating the physicochemical properties and efficacy of recently expired and aged antivenom products from Thailand and Taiwan. Toxicon 2019; 160:55-58. [PMID: 30797900 DOI: 10.1016/j.toxicon.2019.02.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Revised: 01/12/2019] [Accepted: 02/14/2019] [Indexed: 11/17/2022]
Abstract
Gel filtration chromatography and gel electrophoresis revealed minimal protein degradation in lyophilized antivenoms which were 2-year expired (Hemato Polyvalent, Neuro Polyvalent; Thailand) and 18-year expired (Hemato Bivalent, Neuro Bivalent; Taiwan). All expired antivenoms retained immunological binding activity, and were able to neutralize the hemotoxic or neurotoxic as well as lethal effects of the homologous snake venoms. The findings show that antivenoms under proper storage conditions may remain relatively stable beyond the indicated shelf life.
Collapse
Affiliation(s)
- Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Sin Teng Liew
- Department of Biomedical Sciences, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Qian Yi Tan
- Department of Biomedical Sciences, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | | | - Nor Izzati Azmi
- Department of Biomedical Sciences, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Si Mui Sim
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Nget Hong Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Sumana Khomvilai
- Queen Saovabha Memorial Institute, Thai Red Cross Society, Rama IV Road, Bangkok, Thailand
| | - Visith Sitprija
- Queen Saovabha Memorial Institute, Thai Red Cross Society, Rama IV Road, Bangkok, Thailand
| | - Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| |
Collapse
|
45
|
Tan CH, Wong KY, Tan NH, Ng TS, Tan KY. Distinctive Distribution of Secretory Phospholipases A₂ in the Venoms of Afro-Asian Cobras (Subgenus: Naja, Afronaja, Boulengerina and Uraeus). Toxins (Basel) 2019; 11:toxins11020116. [PMID: 30769779 PMCID: PMC6410299 DOI: 10.3390/toxins11020116] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 02/01/2019] [Accepted: 02/07/2019] [Indexed: 12/19/2022] Open
Abstract
The protein abundances of phospholipases A2 in cobra venom proteomes appear to vary among cobra species. To determine the unique distribution of snake venom phospholipases A2 (svPLA2) in the cobras, the svPLA2 activities for 15 cobra species were examined with an acidimetric and a colorimetric assay, using egg yolk suspension and 4-nitro-3-octanoyloxy benzoic acid (NOBA) as the substrate. The colorimetric assay showed significant correlation between svPLA2 enzymatic activities with the svPLA2 protein abundances in venoms. High svPLA2 activities were observed in the venoms of Asiatic spitting cobras (Naja sputatrix, Naja sumatrana) and moderate activities in Asiatic non-spitters (Naja naja, Naja atra, Naja kaouthia), African spitters (subgenus Afronaja), and forest cobra (subgenus Boulengerina). African non-spitting cobras of subgenus Uraeus (Naja haje, Naja annulifera, Naja nivea, Naja senegalensis) showed exceptionally low svPLA2 enzymatic activities. The negligible PLA2 activity in Uraeus cobra venoms implies that PLA2 may not be ubiquitous in all snake venoms. The svPLA2 in cobra envenoming varies depending on the cobra species. This may potentially influence the efficacy of cobra antivenom in specific use for venom neutralization.
Collapse
Affiliation(s)
- Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Kin Ying Wong
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Nget Hong Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Tzu Shan Ng
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
| |
Collapse
|
46
|
Oh AMF, Tan CH, Tan KY, Quraishi NH, Tan NH. Venom proteome of Bungarus sindanus (Sind krait) from Pakistan and in vivo cross-neutralization of toxicity using an Indian polyvalent antivenom. J Proteomics 2019; 193:243-254. [DOI: 10.1016/j.jprot.2018.10.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 10/11/2018] [Accepted: 10/27/2018] [Indexed: 12/13/2022]
|
47
|
Wong KY, Tan CH, Tan KY, Tan NH. Exploring the efficacy and limitation of antivenom neutralization against key venom toxins of Afro-Asian cobras (Naja sp.). Toxicon 2019. [DOI: 10.1016/j.toxicon.2018.10.160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
48
|
Tan CH, Tan KY, Wong KY, Oh AMF, Faisal T, Sim SM, Tan NH. Mapping snake venomics: Insights into biomedical and evolutionary significance of snake toxins. Toxicon 2019. [DOI: 10.1016/j.toxicon.2018.10.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
49
|
Tan KY, Tan CH, Sim SM, Khomvilai S, Sitprija V, Tan NH. Appreciating expired snake antivenoms: a plausible alternative solution to overcome antivenom shortage. Toxicon 2019. [DOI: 10.1016/j.toxicon.2018.10.113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
50
|
Abstract
Reverse-phase high-performance liquid chromatography is commonly employed as a decomplexing strategy in snake venom proteomics. The chromatographic fractions often contain relatively pure toxins that can be assessed functionally for toxicity level through the determination of their median lethal doses (LD50). Further, antivenom efficacy can be evaluated specifically against these venom fractions to understand the limitation of the antivenom as the treatment for snake envenomation. However, methods of toxicity assessment and antivenom evaluation vary across laboratories; hence there is a need to standardize the protocols and parameters, in particular those related to the neutralizing efficacy of antivenom. This chapter outlines the important in vivo techniques and data interpretation that can be applied in the functional study of snake venom proteomes.
Collapse
Affiliation(s)
- Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Kae Yi Tan
- Protein and Interactomic Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|