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Panda R, Singh S, Radhakrishnan RV, Mohanty CR, Shaji IM, Prusty AV, Rajput A. A Case of Cobra Bite in a Term Pregnant Woman: The Obstetric and Wound Management Challenges. Wilderness Environ Med 2023; 34:571-575. [PMID: 37923681 DOI: 10.1016/j.wem.2023.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 08/13/2023] [Accepted: 09/12/2023] [Indexed: 11/07/2023]
Abstract
Snake envenomation is a rare incident during pregnancy and potentially challenging to manage. Snakebites in pregnancy may lead to several complications such as teratogenicity, miscarriage, antepartum hemorrhage, and even intrauterine fetal death. Here, we report a case of a pregnant woman who presented to our emergency department with signs of systemic envenomation following an Indian cobra bite on her foot, highlighting the key obstetric and wound management challenges. She complained of severe pain at the site of the bite and progressive swelling, abdominal pain, and multiple episodes of vomiting, which started 45 min after the bite. She received 10 vials of polyvalent antivenom from a primary hospital and was then referred to our center. The patient underwent emergency cesarean section and later fasciotomy with free-flap reconstruction at the bitten site due to local tissue necrosis. The case was successfully managed by a multidisciplinary team consisting of an emergency physician, obstetrician, and plastic surgeon, saving 2 lives and the limb of the patient.
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Affiliation(s)
- Ritesh Panda
- Department of Trauma and Emergency (Plastic Surgery), All India Institute of Medical Sciences, Bhubaneswar, Odisha, India
| | - Sweta Singh
- Department of Obstetrics and Gynecology, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India
| | | | - Chitta Ranjan Mohanty
- Department of Trauma and Emergency, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India.
| | - Ijas Muhammed Shaji
- Department of Trauma and Emergency, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India
| | - Aditya Vikram Prusty
- Department of Trauma and Emergency, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India
| | - Akanksha Rajput
- Department of Burn and Plastic Surgery, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India
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Soopairin S, Patikorn C, Taychakhoonavudh S. Antivenom preclinical efficacy testing against Asian snakes and their availability in Asia: A systematic review. PLoS One 2023; 18:e0288723. [PMID: 37467278 DOI: 10.1371/journal.pone.0288723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Accepted: 07/04/2023] [Indexed: 07/21/2023] Open
Abstract
BACKGROUND Cross-neutralizing strategy has been applied to improve access to antivenoms, a key to reducing mortality and disability of snakebite envenoming. However, preclinical studies have been conducted to identify antivenoms' cross-neutralizing ability when clinical studies may not be considered ethical. Therefore, this study aimed to identify and summarize scattered evidence regarding the preclinical efficacy of antivenoms against Asian snakes. METHODOLOGY/PRINCIPLE FINDINGS In this systematic review, we searched for articles published until May 30, 2022, in PubMed, Scopus, Web of Science, and Embase. Preclinical studies that reported the available antivenoms' neutralizing ability against Asian snake lethality were included. Quality assessment was performed using the Systematic Review Centre for Laboratory animal Experimentation's risk of bias tool and the adapted the Animal Research Reporting In Vivo Experiments guidelines. The availability of effective antivenoms against Asian snakes was analyzed by comparing data from included studies with snakebite-information and data platforms developed by the World Health Organization. Fifty-two studies were included. Most studies assessed the antivenom efficacy against snakes from Southeast Asia (58%), followed by South Asia (35%) and East Asia (19%). Twenty-two (49%) medically important snakes had antivenom(s) with confirmed neutralizing ability. Situation analyses of the availability of effective antivenoms in Asia demonstrated that locally produced antivenoms did not cover all medically important snakes in each country. Among countries without local antivenom production, preclinical studies were conducted only in Bangladesh, Sri Lanka, and Malaysia. Risk of bias assessment was limited in some domains because of unreported data. CONCLUSIONS/SIGNIFICANCE Cross-neutralizing of antivenoms against some medically important snakes in Asia was confirmed. This strategy may improve access to geographically effective antivenoms and bypass investment in novel antivenom development, especially in countries without local antivenom production. A database should be developed to aid the development of a snakebite-information system.
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Affiliation(s)
- Sutinee Soopairin
- Department of Social and Administrative Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Chanthawat Patikorn
- Department of Social and Administrative Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Suthira Taychakhoonavudh
- Department of Social and Administrative Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
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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] [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.
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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
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Alam MJ, Maruf M, Iqbal MA, Hasan M, Sohan MS, Shariar MR, Haidar IKA, Chowdhury MAW, Ghose A, Hoque KMF, Reza MA. Evaluation of the properties of Bungarus caeruleus venom and checking the efficacy of antivenom used in Bangladesh for its bite treatment. Toxicon X 2023; 17:100149. [PMID: 36654657 PMCID: PMC9841277 DOI: 10.1016/j.toxcx.2023.100149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 12/30/2022] [Accepted: 01/02/2023] [Indexed: 01/05/2023] Open
Abstract
As a disaster-prone country with unique geographical features, snake biting is a major public health concern in Bangladesh. The primary reasons of mortality from snakebite include late presentation to the hospital, low efficacy of antivenom, and a lack of adequate management facilities. Because snake venom characteristics vary depending on geographical location, antivenom should be manufactured from snakes native to the region in which it would be administered. Bungarus caeruleus is a highly venomous snake contributing to the major snakebite issue in Bangladesh. Therefore, the neutralization efficacy of the antivenom against B. caeruleus venom was evaluated in the current study along with the characterization of venom. For biological characterization of venom, RP-HPLC and SDS-PAGE profiling, hemolytic activity, hemorrhagic activity, phospholipases A2 (PLA2) activity, edema inducing activity and histopathological observations were carried out following standard protocol. LD50 of the venom was calculated along with neutralization potency of Incepta antivenom through probit analysis. Results showed that venom possesses phospholipase A2 activity, hemolytic activity and edema inducing activity while hemorrhagic activity was absent in the skin of envenomed mice. Histopathological alterations including necrosis, congestion and infiltrations were observed in envenomed mice organs after hematoxylin and eosin staining. Neutralization study showed that Incepta polyvalent antivenom could neutralize (potency 0.53 mg/ml) the lethal effect in in vitro study on mice. Further investigation on snakebite epidemiology and clinical observations of the envenomed patients will help in combating the snakebite problem more efficiently.
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Affiliation(s)
- Md Jahangir Alam
- Molecular Biology and Protein Science Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Md.Mahmudul.Hasan Maruf
- Molecular Biology and Protein Science Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Md Asif Iqbal
- Molecular Biology and Protein Science Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Mahedi Hasan
- Molecular Biology and Protein Science Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Md Sohanur.Rahman Sohan
- Molecular Biology and Protein Science Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Md Ragib Shariar
- Molecular Biology and Protein Science Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Ibrahim Khalil Al Haidar
- Venom Research Centre, Chittagong Medical College, Chattogram, 4203, Bangladesh,Department of Zoology, University of Chittagong, Chattogram, 4331, Bangladesh
| | - Mohammad Abdul Wahed Chowdhury
- Venom Research Centre, Chittagong Medical College, Chattogram, 4203, Bangladesh,Department of Zoology, University of Chittagong, Chattogram, 4331, Bangladesh
| | - Aniruddha Ghose
- Venom Research Centre, Chittagong Medical College, Chattogram, 4203, Bangladesh,Department of Medicine, Chittagong Medical College, Chattogram, 4203, Bangladesh
| | - Kazi Md Faisal Hoque
- Molecular Biology and Protein Science Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Md Abu Reza
- Molecular Biology and Protein Science Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh,Corresponding author.
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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] [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.
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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,
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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] [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.
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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
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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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 09/28/2022] [Accepted: 10/09/2022] [Indexed: 11/06/2022]
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Srimathi R, Sabareesh V, Gurunathan J. Naringenin isolated from Citrus reticulata blanco fruit peel inhibits the toxicity of snake venom proteins - An in vitro and in vivo study. Toxicon 2022; 220:106943. [DOI: 10.1016/j.toxicon.2022.106943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 10/10/2022] [Accepted: 10/10/2022] [Indexed: 11/15/2022]
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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] [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.
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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.)
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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] [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.
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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.)
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11
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Huynh TM, Silva A, Isbister GK, Hodgson WC. Isolation and Characterization of Two Postsynaptic Neurotoxins From Indian Cobra ( Naja Naja) Venom. Front Pharmacol 2022; 13:815079. [PMID: 35418867 PMCID: PMC8996157 DOI: 10.3389/fphar.2022.815079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 03/10/2022] [Indexed: 11/19/2022] Open
Abstract
The Indian Cobra (Naja naja) is among the “Big Four” responsible for most of the snakebite envenoming cases in India. Although recent proteomic studies suggest the presence of postsynaptic neurotoxins in N. naja venom, little is known about the pharmacology of these toxins. We isolated and characterized α-Elapitoxin-Nn2a (α-EPTX-Nn2a; 7020 Da) and α-Elapitoxin-Nn3a (α-EPTX-Nn3a; 7807 Da), a short-chain and long-chain postsynaptic neurotoxin, respectively, which constitute 1 and 3% of N. naja venom. α-EPTX-Nn2a (100–300 nM) and α-EPTX-Nn3a (100–300 nM) both induced concentration-dependent inhibition of indirect twitches and abolished contractile responses of tissues to exogenous acetylcholine and carbachol, in the chick biventer cervicis nerve-muscle preparation. The prior incubation of tissues with Indian polyvalent antivenom (1 ml/0.6 mg) prevented the in vitro neurotoxic effects of α-EPTX-Nn2a (100 nM) and α-EPTX-Nn3a (100 nM). The addition of Indian polyvalent antivenom (1 ml/0.6 mg), at the t90 time point, could not reverse the in vitro neurotoxicity of α-EPTX-Nn2a (100 nM). The in vitro neurotoxicity of α-EPTX-Nn3a (100 nM) was partially reversed by the addition of Indian polyvalent antivenom (1 ml/0.6 mg), as well as repeated washing of the tissue. α-EPTX-Nn2a displayed non-competitive antagonism of concentration-response curves to carbachol, with a pA2 of 8.01. In contrast, α-EPTX-Nn3a showed reversible antagonism of concentration-response curves to carbachol, with a pA2 of 8.17. De novo sequencing of α-EPTX-Nn2a and α-EPTX-Nn3a showed a short-chain and long-chain postsynaptic neurotoxin, respectively, with 62 and 71 amino acids. The important observation made in this study is that antivenom can reverse the neurotoxicity of the clinically important long-chain neurotoxin, but not the short-chain neurotoxin, from N. naja venom.
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Affiliation(s)
- Tam M Huynh
- Monash Venom Group, Department of Pharmacology, Biomedical Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Anjana Silva
- Monash Venom Group, Department of Pharmacology, Biomedical Discovery Institute, Monash University, Clayton, VIC, Australia.,Department of Parasitology, Faculty of Medicine and Allied Sciences, Rajarata University of Sri Lanka, Saliyapura, Sri Lanka
| | - Geoffrey K Isbister
- Monash Venom Group, Department of Pharmacology, Biomedical Discovery Institute, Monash University, Clayton, VIC, Australia.,Clinical Toxicology Research Group, University of Newcastle, Newcastle, NSW, Australia
| | - Wayne C Hodgson
- Monash Venom Group, Department of Pharmacology, Biomedical Discovery Institute, Monash University, Clayton, VIC, Australia
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12
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Snake Venomics: Fundamentals, Recent Updates, and a Look to the Next Decade. Toxins (Basel) 2022; 14:toxins14040247. [PMID: 35448856 PMCID: PMC9028316 DOI: 10.3390/toxins14040247] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 03/18/2022] [Accepted: 03/21/2022] [Indexed: 01/11/2023] Open
Abstract
Venomic research, powered by techniques adapted from proteomics, transcriptomics, and genomics, seeks to unravel the diversity and complexity of venom through which knowledge can be applied in the treatment of envenoming, biodiscovery, and conservation. Snake venom proteomics is most extensively studied, but the methods varied widely, creating a massive amount of information which complicates data comparison and interpretation. Advancement in mass spectrometry technology, accompanied by growing databases and sophisticated bioinformatic tools, has overcome earlier limitations of protein identification. The progress, however, remains challenged by limited accessibility to samples, non-standardized quantitative methods, and biased interpretation of -omic data. Next-generation sequencing (NGS) technologies enable high-throughput venom-gland transcriptomics and genomics, complementing venom proteomics by providing deeper insights into the structural diversity, differential expression, regulation and functional interaction of the toxin genes. Venomic tissue sampling is, however, difficult due to strict regulations on wildlife use and transfer of biological materials in some countries. Limited resources for techniques and funding are among other pertinent issues that impede the progress of venomics, particularly in less developed regions and for neglected species. Genuine collaboration between international researchers, due recognition of regional experts by global organizations (e.g., WHO), and improved distribution of research support, should be embraced.
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13
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Analysis of the Composition of Deinagkistrodon acutus Snake Venom Based on Proteomics, and Its Antithrombotic Activity and Toxicity Studies. Molecules 2022; 27:molecules27072229. [PMID: 35408629 PMCID: PMC9000436 DOI: 10.3390/molecules27072229] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/25/2022] [Accepted: 03/28/2022] [Indexed: 02/06/2023] Open
Abstract
There is a strong correlation between the composition of Deinagkistrodon acutus venom proteins and their potential pharmacological effects. The proteomic analysis revealed 103 proteins identified through label-free proteomics from 30 different snake venom families. Phospholipase A2 (30.0%), snaclec (21.0%), antithrombin (17.8%), thrombin (8.1%) and metalloproteinases (4.2%) were the most abundant proteins. The main toxicity of Deinagkistrodon acutus venom is hematotoxicity and neurotoxicity, and it acts on the lung. Deinagkistrodon acutus venom may have anticoagulant and antithrombotic effects. In summary, the protein profile and related toxicity and pharmacological activity of Deinagkistrodon acutus venom from southwest China were put forward for the first time. In addition, we revealed the relationship between the main toxicity, pharmacological effects, and the protein components of snake venom.
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14
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Varespladib (LY315920) rescued mice from fatal neurotoxicity caused by venoms of five major Asiatic kraits (Bungarus spp.) in an experimental envenoming and rescue model. Acta Trop 2022; 227:106289. [PMID: 34929179 DOI: 10.1016/j.actatropica.2021.106289] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 12/16/2021] [Accepted: 12/16/2021] [Indexed: 11/23/2022]
Abstract
The venoms of Asiatic kraits (Bungarus spp.) contain various neurotoxic phospholipases A2 (beta-bungarotoxins) which can irreversibly damage motor nerve terminals, resulting in rapidly fatal suffocation by respiratory muscle paralysis or oral airway obstruction. Hence, there is a need of adjunct therapy at the pre-hospital stage to prevent or delay the onset of neurotoxicity, so that antivenom can be given within golden hour before the envenoming becomes antivenom-resistant. This study investigated the efficacy of varespladib, a small molecule PLA2 (phospholipase A2) inhibitor, given as a bolus subcutaneously upon the onset of krait venom-induced paralysis in a mouse experimental envenoming and rescue model, where the severity of neurotoxicity was scored and the survival rate was monitored over 24 h. Varespladib at 10 mg/kg effectively alleviated the neurotoxicity of Bungarus sindanus, Bungarus multicinctus and Bungarus fasciatus venoms, and rescued all mice from venom-induced lethality (100% survival). Varespladib at this dose, however, only partially reduced the neurotoxicity of Bungarus caeruleus and Bungarus candidus venoms, while all challenged mice were dead by 23 h (B. caeruleus) and 12 h (B. candidus). An increased dose of varespladib at 20 mg/kg markedly abated the venom neurotoxicity past 8 h of envenoming, and protected the mice from venom lethality (B. caeruleus: 75% survival; B. candidus: 100% survival). The finding is consistent with previous studies which demonstrated varespladib's inhibitory effect against some snake venoms. The findings suggest varespladib could be repurposed as an emergency drug for prevention or rescue (if given early enough) from the acute, neurotoxic envenoming syndromes caused by various major krait species in Asia.
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15
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Attarde S, Iyer A, Khochare S, Shaligram U, Vikharankar M, Sunagar K. The Preclinical Evaluation of a Second-Generation Antivenom for Treating Snake Envenoming in India. Toxins (Basel) 2022; 14:toxins14030168. [PMID: 35324665 PMCID: PMC8950585 DOI: 10.3390/toxins14030168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/03/2022] [Accepted: 01/06/2022] [Indexed: 11/23/2022] Open
Abstract
Snake envenoming afflicts the Indian subcontinent with the highest rates of mortality (47,000) and morbidity globally. The only effective treatment for snakebites is the administration of antivenom, which is produced by the hyperimmunisation of equines. Commercial Indian antivenoms, however, have been shown to exhibit a poor preclinical performance in neutralising venom, as a result of inter- and intrapopulation snake venom variation. Additionally, their poor dose effectiveness necessitates the administration of larger volumes of antivenom for treatment, leading to several harmful side effects in snakebite victims, including serum sickness and fatal anaphylaxis. In this study, we employed chromatographic purification to enhance the dose efficacy of commercial Indian antivenoms. The efficacy of this ‘second-generation’ antivenom was comparatively evaluated against six other marketed antivenoms using a number of in vitro and in vivo preclinical assays, which revealed its superior venom recognition capability. Enhanced purity also resulted in significant improvements in dose effectiveness, as the ‘second-generation’ antivenom exhibited a 3 to 4.5 times increased venom neutralisation potential. Furthermore, preclinical assays revealed the increased effectiveness of the ‘second-generation’ antivenom in countering morbid effects inflicted by the ‘big four’ Indian snakes. Thus, we demonstrate the role of simpler purification steps in significantly enhancing the effectiveness of snakebite therapy in regions that are most affected by snakebites.
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Affiliation(s)
- Saurabh Attarde
- Evolutionary Venomics Lab, Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, Karnataka, India; (S.A.); (A.I.); (S.K.)
| | - Ashwin Iyer
- Evolutionary Venomics Lab, Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, Karnataka, India; (S.A.); (A.I.); (S.K.)
| | - Suyog Khochare
- Evolutionary Venomics Lab, Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, Karnataka, India; (S.A.); (A.I.); (S.K.)
| | - Umesh Shaligram
- Serum Institute of India Pvt. Ltd., 212/2, Hadapsar, Off Soli Poonawalla Road, Pune 411028, Maharashtra, India; (U.S.); (M.V.)
| | - Mayur Vikharankar
- Serum Institute of India Pvt. Ltd., 212/2, Hadapsar, Off Soli Poonawalla Road, Pune 411028, Maharashtra, India; (U.S.); (M.V.)
| | - Kartik Sunagar
- Evolutionary Venomics Lab, Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, Karnataka, India; (S.A.); (A.I.); (S.K.)
- Correspondence:
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16
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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] [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.
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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
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17
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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] [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.
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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
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18
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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] [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.
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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;
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19
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Liu BS, Jiang BR, Hu KC, Liu CH, Hsieh WC, Lin MH, Sung WC. Development of a Broad-Spectrum Antiserum against Cobra Venoms Using Recombinant Three-Finger Toxins. Toxins (Basel) 2021; 13:556. [PMID: 34437427 PMCID: PMC8402450 DOI: 10.3390/toxins13080556] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 08/02/2021] [Accepted: 08/05/2021] [Indexed: 11/16/2022] Open
Abstract
Three-finger toxins (3FTXs) are the most clinically relevant components in cobra (genus Naja) venoms. Administration of the antivenom is the recommended treatment for the snakebite envenomings, while the efficacy to cross-neutralize the different cobra species is typically limited, which is presumably due to intra-specific variation of the 3FTXs composition in cobra venoms. Targeting the clinically relevant venom components has been considered as an important factor for novel antivenom design. Here, we used the recombinant type of long-chain α-neurotoxins (P01391), short-chain α-neurotoxins (P60770), and cardiotoxin A3 (P60301) to generate a new immunogen formulation and investigated the potency of the resulting antiserum against the venom lethality of three medially important cobras in Asia, including the Thai monocled cobra (Naja kaouthia), the Taiwan cobra (Naja atra), and the Thai spitting cobra (Naja Siamensis) snake species. With the fusion of protein disulfide isomerase and the low-temperature settings, the correct disulfide bonds were built on these recombinant 3FTXs (r3FTXs), which were confirmed by the circular dichroism spectra and tandem mass spectrometry. Immunization with r3FTX was able to induce the specific antibody response to the native 3FTXs in cobra venoms. Furthermore, the horse and rabbit antiserum raised by the r3FTX mixture is able to neutralize the venom lethality of the selected three medically important cobras. Thus, the study demonstrated that the r3FTXs are potential immunogens in the development of novel antivenom with broad neutralization activity for the therapeutic treatment of victims involving cobra snakes in countries.
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Affiliation(s)
- Bing-Sin Liu
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli 35053, Taiwan; (B.-S.L.); (B.-R.J.); (K.-C.H.); (M.-H.L.)
| | - Bo-Rong Jiang
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli 35053, Taiwan; (B.-S.L.); (B.-R.J.); (K.-C.H.); (M.-H.L.)
| | - Kai-Chieh Hu
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli 35053, Taiwan; (B.-S.L.); (B.-R.J.); (K.-C.H.); (M.-H.L.)
| | - Chien-Hsin Liu
- Centers for Disease Control, Ministry of Health and Welfare, Taipei 10050, Taiwan; (C.-H.L.); (W.-C.H.)
| | - Wen-Chin Hsieh
- Centers for Disease Control, Ministry of Health and Welfare, Taipei 10050, Taiwan; (C.-H.L.); (W.-C.H.)
| | - Min-Han Lin
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli 35053, Taiwan; (B.-S.L.); (B.-R.J.); (K.-C.H.); (M.-H.L.)
| | - Wang-Chou Sung
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli 35053, Taiwan; (B.-S.L.); (B.-R.J.); (K.-C.H.); (M.-H.L.)
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20
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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). COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY 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] [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.
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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.
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21
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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] [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.
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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
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22
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Samianifard M, Nazari A, Tahoori F, Mohamadpour Dounighi N. Proteome Analysis of Toxic Fractions of Iranian Cobra (Naja naja Oxiana) Snake Venom Using Two-Dimensional Electrophoresis and Mass Spectrometry. ARCHIVES OF RAZI INSTITUTE 2021; 76:127-138. [PMID: 33818965 DOI: 10.22092/ari.2020.128766.1428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Accepted: 03/14/2020] [Indexed: 09/30/2022]
Abstract
Snake venoms are mostly composed of various proteins and peptides with toxicity and pharmacological effects depending on their geographical sources. Naja naja oxiana is one of the most medically important venomous snakes in Iran and Central Asia. The bite of this type of snake can cause severe pain and swelling, as well as neurotoxicity. Without medical treatment, symptoms quickly worsen and death can occur soon. A detailed understanding of venom components can provide new insight into the production of antivenom against toxic agents instead of crude venom. Specific antibodies against toxic fractions are of utmost importance in neutralizing crude venom. Therefore, the proteome profile of these fractions of Naja naja oxidana venom was analyzed using fractionation by gel filtration, two-dimensional electrophoresis, mass spectrometry, and data mining. Base on the results, in total, 32 spots were detected and categorized into three protein families, namely three-finger toxin (3FTx), phospholipase, and Cysteine-rich secretory proteins (CRISP). These proteins consist of more than 70% crude venom all with a molecular weight below 25 kDa. The 3FTx as a highly diverse constituent in the venom of Naja species was in large quantity in this district. Short-chain neurotoxins, including short neurotoxin, cytotoxin, and muscarinic toxin-like protein, were in abundance, respectively. In conclusion, the recognition of toxic fractions of Naja naja oxiana in this region could be of great help in the production of an effective antivenom against similar compositions. It can also help the medical care department to find out the clinical sign of cobra venom. To the best of our knowledge, this was the first study to report the proteomic of toxic fractions of Naja naja oxiana in Iran.
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Affiliation(s)
- M Samianifard
- Department of Proteomics-Biochemistry, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
| | - A Nazari
- Department of Proteomics-Biochemistry, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran.,Department of Proteomics-Biochemistry, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
| | - F Tahoori
- Department of Human Bacterial Vaccine, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
| | - N Mohamadpour Dounighi
- Department of Venomous Animal, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
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Yu C, Yue Y, Yin X, Li R, Yu H, Li P. Identifying and revealing the geographical variation in Nemopilema nomurai venom metalloprotease and phospholipase A 2 activities. CHEMOSPHERE 2021; 266:129164. [PMID: 33310516 DOI: 10.1016/j.chemosphere.2020.129164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 11/16/2020] [Accepted: 11/29/2020] [Indexed: 06/12/2023]
Abstract
Venom geographical variation is common among venomous animals. This phenomenon presents problems in the development of clinical treatments and medicines against envenomation. The venomous giant jellyfish Nemopilema nomurai, Scyphozoan, is a blooming jellyfish species in the Yellow Sea and the East China Sea that causes numerous jellyfish sting cases every year. Metalloprotease and phospholipase A2 (PLA2) are the main components in Nemopilema nomurai venom and may activate many toxicities, such as hemolysis, inflammation and lethality. Geographical variation in the content and activity of these enzymes may cause different symptoms and therapeutic problems. For the first time, we verified metalloprotease and PLA2 geographical variation in Nemopilema nomurai venom by performing a comparative analysis of 31 venom samples by SDS-PAGE, analyzing protease zymography, enzymatic activity, and drawing contour maps. Band locations and intensities of SDS-PAGE and protease zymograms showed geographical differences. The enzymatic activities of both metalloprotease and PLA2 showed a trend of geographic regularity. The distribution patterns of these activities are directly shown in contour maps. Metalloproteinase activity was lower near the coast. PLA2-like activity was lower in the Southern Yellow Sea. We surmised that metalloproteinase and PLA2-like activities might be related to venom ontogeny and species abundance respectively, and influenced by similar environmental factors. This study provides a theoretical basis for further ecological and medical studies of Nemopilema nomurai jellyfish venom.
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Affiliation(s)
- Chunlin Yu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao, 266071, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yang Yue
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao, 266071, China
| | - Xiujing Yin
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao, 266071, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Rongfeng Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao, 266071, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, No. 1 Wenhai Road, Qingdao, 266237, China
| | - Huahua Yu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao, 266071, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, No. 1 Wenhai Road, Qingdao, 266237, China.
| | - Pengcheng Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao, 266071, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, No. 1 Wenhai Road, Qingdao, 266237, China
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Senji Laxme RR, Attarde S, Khochare S, Suranse V, Martin G, Casewell NR, Whitaker R, Sunagar K. Biogeographical venom variation in the Indian spectacled cobra (Naja naja) underscores the pressing need for pan-India efficacious snakebite therapy. PLoS Negl Trop Dis 2021; 15:e0009150. [PMID: 33600405 PMCID: PMC7924803 DOI: 10.1371/journal.pntd.0009150] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 03/02/2021] [Accepted: 01/18/2021] [Indexed: 01/08/2023] Open
Abstract
Background Snake venom composition is dictated by various ecological and environmental factors, and can exhibit dramatic variation across geographically disparate populations of the same species. This molecular diversity can undermine the efficacy of snakebite treatments, as antivenoms produced against venom from one population may fail to neutralise others. India is the world’s snakebite hotspot, with 58,000 fatalities and 140,000 morbidities occurring annually. Spectacled cobra (Naja naja) and Russell’s viper (Daboia russelii) are known to cause the majority of these envenomations, in part due to their near country-wide distributions. However, the impact of differing ecologies and environment on their venom compositions has not been comprehensively studied. Methods Here, we used a multi-disciplinary approach consisting of venom proteomics, biochemical and pharmacological analyses, and in vivo research to comparatively analyse N. naja venoms across a broad region (>6000 km; seven populations) covering India’s six distinct biogeographical zones. Findings By generating the most comprehensive pan-Indian proteomic and toxicity profiles to date, we unveil considerable differences in the composition, pharmacological effects and potencies of geographically-distinct venoms from this species and, through the use of immunological assays and preclinical experiments, demonstrate alarming repercussions on antivenom therapy. We find that commercially-available antivenom fails to effectively neutralise envenomations by the pan-Indian populations of N. naja, including a complete lack of neutralisation against the desert Naja population. Conclusion Our findings highlight the significant influence of ecology and environment on snake venom composition and potency, and stress the pressing need to innovate pan-India effective antivenoms to safeguard the lives, limbs and livelihoods of the country’s 200,000 annual snakebite victims. Annually, India is burdened by the highest number of snake envenomations across the globe, with over 58,000 fatalities and three times the number of morbidities, predominantly affecting the rural agrarian communities. The spectacled cobra (Naja naja) and Russell’s viper (Daboia russelii) are responsible for the vast majority of envenomations in the country, in part, due to their near country-wide distributions. In this study, we unveil the astounding differences in venom composition of N. naja from six different biogeographical zones across the country (>6000 km). We provide a comprehensive account of their disparate venom proteomic profiles, biochemical and pharmacological effects, and the associated potencies. Our study uncovers alarming differences in the efficacy of the marketed polyvalent antivenoms in neutralising these venoms, thereby, emphasising the pressing need to develop dose-efficacious and pan-India effective antivenoms for the treatment of snakebites in the country. This study also highlights the significant influence of ecology and diverse environments on the venom variability, insinuating the necessity for innovating cost-effective and pan-India efficacious solutions to safeguard the lives, limbs and livelihoods of India’s two hundred thousand annual snakebite victims.
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Affiliation(s)
- R. R. Senji Laxme
- Evolutionary Venomics Lab. Centre for Ecological Sciences, Indian Institute of Science, Bangalore, Karnataka, India
| | - Saurabh Attarde
- Evolutionary Venomics Lab. Centre for Ecological Sciences, Indian Institute of Science, Bangalore, Karnataka, India
| | - Suyog Khochare
- Evolutionary Venomics Lab. Centre for Ecological Sciences, Indian Institute of Science, Bangalore, Karnataka, India
| | - Vivek Suranse
- Evolutionary Venomics Lab. Centre for Ecological Sciences, Indian Institute of Science, Bangalore, Karnataka, India
| | - Gerard Martin
- The Liana Trust, Survey #1418/1419 Rathnapuri, Hunsur, Karnataka, India
| | - Nicholas R. Casewell
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - Romulus Whitaker
- Madras Crocodile Bank Trust/Centre for Herpetology, Mamallapuram, Tamil Nadu, India
| | - Kartik Sunagar
- Evolutionary Venomics Lab. Centre for Ecological Sciences, Indian Institute of Science, Bangalore, Karnataka, India
- * E-mail:
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25
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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] [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.
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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;
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26
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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] [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.
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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
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27
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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] [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.
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Affiliation(s)
| | - Aymeric Bourges
- University of Malaya, Malaysia; Université Libre de Bruxelles, Belgium
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28
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Tan MS, Carranza MS, Linis V, Malabed R, Reyes YA, Franco F, Oyong G. Antioxidant, cytotoxic, and anti-venom activity of Alstonia parvifolia Merr. Bark. Asian Pac J Trop Biomed 2021. [DOI: 10.4103/2221-1691.326100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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29
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Mukherjee AK. Species-specific and geographical variation in venom composition of two major cobras in Indian subcontinent: Impact on polyvalent antivenom therapy. Toxicon 2020; 188:150-158. [DOI: 10.1016/j.toxicon.2020.10.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 10/13/2020] [Accepted: 10/27/2020] [Indexed: 12/18/2022]
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30
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Lynagh T, Kiontke S, Meyhoff-Madsen M, Gless BH, Johannesen J, Kattelmann S, Christiansen A, Dufva M, Laustsen AH, Devkota K, Olsen CA, Kümmel D, Pless SA, Lohse B. Peptide Inhibitors of the α-Cobratoxin-Nicotinic Acetylcholine Receptor Interaction. J Med Chem 2020; 63:13709-13718. [PMID: 33143415 PMCID: PMC7705965 DOI: 10.1021/acs.jmedchem.0c01202] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
![]()
Venomous snakebites cause >100
000 deaths every year, in many cases
via potent depression of human neuromuscular signaling by snake α-neurotoxins.
Emergency therapy still relies on antibody-based antivenom, hampered
by poor access, frequent adverse reactions, and cumbersome production/purification.
Combining high-throughput discovery and subsequent structure–function
characterization, we present simple peptides that bind α-cobratoxin
(α-Cbtx) and prevent its inhibition of nicotinic acetylcholine
receptors (nAChRs) as a lead for the development of alternative antivenoms.
Candidate peptides were identified by phage display and deep sequencing,
and hits were characterized by electrophysiological recordings, leading
to an 8-mer peptide that prevented α-Cbtx inhibition of nAChRs.
We also solved the peptide:α-Cbtx cocrystal structure, revealing
that the peptide, although of unique primary sequence, binds to α-Cbtx
by mimicking structural features of the nAChR binding pocket. This
demonstrates the potential of small peptides to neutralize lethal
snake toxins in vitro, establishing a potential route to simple, synthetic,
low-cost antivenoms.
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Affiliation(s)
- Timothy Lynagh
- Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgate 55, 5008 Bergen, Norway.,Center for Biopharmaceuticals & Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Stephan Kiontke
- Division of Structural Biology, Department of Biology/Chemistry, University of Osnabrück, Barbarastraße 13, Osnabrück 49076, Germany.,Faculty of Biology, Department of Plant Physiology and Photobiology, Philipps-Universität Marburg, Karl-von-Frisch-Straße 8, 35032 Marburg, Germany
| | - Maria Meyhoff-Madsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Bengt H Gless
- Center for Biopharmaceuticals & Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Jónas Johannesen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Sabrina Kattelmann
- Institute of Biochemistry, University of Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Anders Christiansen
- Fluid Array Systems and Technology, Nano and Bio-physical Systems, Department of Health Technology, Technical University of Denmark, Building 423 Produktionstorvet, DK-2800 Kongens Lyngby, Denmark
| | - Martin Dufva
- Fluid Array Systems and Technology, Nano and Bio-physical Systems, Department of Health Technology, Technical University of Denmark, Building 423 Produktionstorvet, DK-2800 Kongens Lyngby, Denmark
| | - Andreas H Laustsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Kanchan Devkota
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Christian A Olsen
- Center for Biopharmaceuticals & Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Daniel Kümmel
- Division of Structural Biology, Department of Biology/Chemistry, University of Osnabrück, Barbarastraße 13, Osnabrück 49076, Germany.,Institute of Biochemistry, University of Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Stephan Alexander Pless
- Center for Biopharmaceuticals & Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Brian Lohse
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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Yu C, Yu H, Li P. Highlights of animal venom research on the geographical variations of toxin components, toxicities and envenomation therapy. Int J Biol Macromol 2020; 165:2994-3006. [PMID: 33122066 DOI: 10.1016/j.ijbiomac.2020.10.190] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 10/22/2020] [Accepted: 10/23/2020] [Indexed: 01/22/2023]
Abstract
Geographical variation of animal venom is common among venomous animals. This kind of intraspecific variation based on geographical location mainly concerned from envenomation cases and brought new problems in animal venom studies, including venom components regulatory mechanisms, differentiation of venom activities, and clinical treatment methods. At present, food is considered as the most related factor influencing venom development. Related research defined the variational venomous animal species by the comparison of venom components and activities in snakes, jellyfish, scorpions, cone snails, ants, parasitoid wasps, spiders and toads. In snake venom studies, researchers found that antivenom effectiveness was variated to different located venom samples. As described in some snake venom research, developing region-specific antivenom is the development trend. The difficulties of developing region-specific antivenom and theoretical solutions have been discussed. This review summarized biological studies of animal venom geographical variation by species, compared venom components and major biological activities of the vary venom from the same species, and listed the basic methods in comparing venom protein compositions and major toxicity differences to provide a comprehensive reference.
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Affiliation(s)
- Chunlin Yu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao 266071, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Huahua Yu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, No. 1 Wenhai Road, Qingdao 266237, China.
| | - Pengcheng Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, No. 1 Wenhai Road, Qingdao 266237, China.
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32
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Proteomic Investigations of Two Pakistani Naja Snake Venoms Species Unravel the Venom Complexity, Posttranslational Modifications, and Presence of Extracellular Vesicles. Toxins (Basel) 2020; 12:toxins12110669. [PMID: 33105837 PMCID: PMC7690644 DOI: 10.3390/toxins12110669] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 10/06/2020] [Accepted: 10/20/2020] [Indexed: 12/31/2022] Open
Abstract
Latest advancement of omics technologies allows in-depth characterization of venom compositions. In the present work we present a proteomic study of two snake venoms of the genus Naja i.e., Naja naja (black cobra) and Naja oxiana (brown cobra) of Pakistani origin. The present study has shown that these snake venoms consist of a highly diversified proteome. Furthermore, the data also revealed variation among closely related species. High throughput mass spectrometric analysis of the venom proteome allowed to identify for the N. naja venom 34 protein families and for the N. oxiana 24 protein families. The comparative evaluation of the two venoms showed that N. naja consists of a more complex venom proteome than N. oxiana venom. Analysis also showed N-terminal acetylation (N-ace) of a few proteins in both venoms. To the best of our knowledge, this is the first study revealing this posttranslational modification in snake venom. N-ace can shed light on the mechanism of regulation of venom proteins inside the venom gland. Furthermore, our data showed the presence of other body proteins, e.g., ankyrin repeats, leucine repeats, zinc finger, cobra serum albumin, transferrin, insulin, deoxyribonuclease-2-alpha, and other regulatory proteins in these venoms. Interestingly, our data identified Ras-GTpase type of proteins, which indicate the presence of extracellular vesicles in the venom. The data can support the production of distinct and specific anti-venoms and also allow a better understanding of the envenomation and mechanism of distribution of toxins. Data are available via ProteomeXchange with identifier PXD018726.
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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] [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.
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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
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Jenkins TP, Laustsen AH. Cost of Manufacturing for Recombinant Snakebite Antivenoms. Front Bioeng Biotechnol 2020; 8:703. [PMID: 32766215 PMCID: PMC7381290 DOI: 10.3389/fbioe.2020.00703] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 06/04/2020] [Indexed: 01/14/2023] Open
Abstract
Snakebite envenoming is a neglected tropical disease that affects millions of people across the globe. It has been suggested that recombinant antivenoms based on mixtures of human monoclonal antibodies, which target key toxins of medically important snake venom, could present a promising avenue toward the reduction of morbidity and mortality of envenomated patients. However, since snakebite envenoming is a disease of poverty, it is pivotal that next-generation therapies are affordable to those most in need; this warrants analysis of the cost dynamics of recombinant antivenom manufacture. Therefore, we present, for the first time, a bottom-up analysis of the cost dynamics surrounding the production of future recombinant antivenoms based on available industry data. We unravel the potential impact that venom volume, abundance of medically relevant toxins in a venom, and the molecular weight of these toxins may have on the final product cost. Furthermore, we assess the roles that antibody molar mass, manufacturing and purification strategies, formulation, antibody efficacy, and potential cross-reactivity play in the complex cost dynamics of recombinant antivenom manufacture. Notably, according to our calculations, it appears that such next-generation antivenoms based on cocktails of monoclonal immunoglobulin Gs (IgGs) could be manufacturable at a comparable or lower cost to current plasma-derived antivenoms, which are priced at USD 13-1120 per treatment. We found that monovalent recombinant antivenoms based on IgGs could be manufactured for USD 20-225 per treatment, while more complex polyvalent recombinant antivenoms based on IgGs could be manufactured for USD 48-1354 per treatment. Finally, we investigated the prospective cost of manufacturing for recombinant antivenoms based on alternative protein scaffolds, such as DARPins and nanobodies, and highlight the potential utility of such scaffolds in the context of low-cost manufacturing. In conclusion, the development of recombinant antivenoms not only holds a promise for improving therapeutic parameters, such as safety and efficacy, but could possibly also lead to a more competetive cost of manufacture of antivenom products for patients worldwide.
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Affiliation(s)
- Timothy Patrick Jenkins
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
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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] [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.
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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.
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Kazemi-Lomedasht F, Yamabhai M, Sabatier JM, Behdani M, Zareinejad MR, Shahbazzadeh D. Development of a human scFv antibody targeting the lethal Iranian cobra (Naja oxiana) snake venom. Toxicon 2019; 171:78-85. [DOI: 10.1016/j.toxicon.2019.10.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 10/05/2019] [Accepted: 10/10/2019] [Indexed: 11/24/2022]
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Comparative proteomes, immunoreactivities and neutralization of procoagulant activities of Calloselasma rhodostoma (Malayan pit viper) venoms from four regions in Southeast Asia. Toxicon 2019; 169:91-102. [DOI: 10.1016/j.toxicon.2019.08.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 07/20/2019] [Accepted: 08/13/2019] [Indexed: 12/20/2022]
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Ashraf MR, Nadeem A, Smith EN, Javed M, Smart U, Yaqub T, Hashmi AS. Molecular phylogenetics of Black Cobra (Naja naja) in Pakistan. ELECTRON J BIOTECHN 2019. [DOI: 10.1016/j.ejbt.2019.10.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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39
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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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 06/13/2019] [Accepted: 06/25/2019] [Indexed: 11/30/2022]
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40
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Deka A, Gogoi A, Das D, Purkayastha J, Doley R. Proteomics of Naja kaouthia venom from North East India and assessment of Indian polyvalent antivenom by third generation antivenomics. J Proteomics 2019; 207:103463. [DOI: 10.1016/j.jprot.2019.103463] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 07/15/2019] [Accepted: 07/21/2019] [Indexed: 11/25/2022]
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41
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Albulescu LO, Kazandjian T, Slagboom J, Bruyneel B, Ainsworth S, Alsolaiss J, Wagstaff SC, Whiteley G, Harrison RA, Ulens C, Kool J, Casewell NR. A Decoy-Receptor Approach Using Nicotinic Acetylcholine Receptor Mimics Reveals Their Potential as Novel Therapeutics Against Neurotoxic Snakebite. Front Pharmacol 2019; 10:848. [PMID: 31417406 PMCID: PMC6683245 DOI: 10.3389/fphar.2019.00848] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 07/02/2019] [Indexed: 12/24/2022] Open
Abstract
Snakebite is a neglected tropical disease that causes 138,000 deaths each year. Neurotoxic snake venoms contain small neurotoxins, including three-finger toxins (3FTxs), which can cause rapid paralysis in snakebite victims by blocking postsynaptic transmission via nicotinic acetylcholine receptors (nAChRs). These toxins are typically weakly immunogenic and thus are often not effectively targeted by current polyclonal antivenom therapies. We investigated whether nAChR mimics, also known as acetylcholine binding proteins (AChBPs), could effectively capture 3FTxs and therefore be developed as a novel class of snake-generic therapeutics for combatting neurotoxic envenoming. First, we identified the binding specificities of 3FTx from various medically important elapid snake venoms to nAChR using two recombinant nAChR mimics: the AChBP from Lymnaea stagnalis and a humanized neuronal α7 version (α7-AChBP). We next characterized these AChBP-bound and unbound fractions using SDS-PAGE and mass spectrometry. Interestingly, both mimics effectively captured long-chain 3FTxs from multiple snake species but largely failed to capture the highly related short-chain 3FTxs, suggesting a high level of binding specificity. We next investigated whether nAChR mimics could be used as snakebite therapeutics. We showed that while α7-AChBP alone did not protect against Naja haje (Egyptian cobra) venom lethality in vivo, it significantly prolonged survival times when coadministered with a nonprotective dose of antivenom. Thus, nAChR mimics are capable of neutralizing specific venom toxins and may be useful adjunct therapeutics for improving the safety and affordability of existing snakebite treatments by reducing therapeutic doses. Our findings justify exploring the future development of AChBPs as potential snakebite treatments.
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Affiliation(s)
- Laura-Oana Albulescu
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Taline Kazandjian
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Julien Slagboom
- AIMMS Division of BioMolecular Analysis, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Ben Bruyneel
- AIMMS Division of BioMolecular Analysis, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Stuart Ainsworth
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Jaffer Alsolaiss
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Simon C Wagstaff
- Bioinformatics Unit, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Gareth Whiteley
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Robert A Harrison
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom.,Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Chris Ulens
- Laboratory of Structural Neurobiology, Department of Cellular and Molecular Medicine, Faculty of Medicine, KU Leuven, Leuven, Belgium
| | - Jeroen Kool
- AIMMS Division of BioMolecular Analysis, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Nicholas R Casewell
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom.,Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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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] [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.
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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.
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Comparative analysis of Naja kaouthia venom from North-East India and Bangladesh and its cross reactivity with Indian polyvalent antivenoms. Toxicon 2019; 164:31-43. [DOI: 10.1016/j.toxicon.2019.03.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 03/26/2019] [Accepted: 03/31/2019] [Indexed: 01/01/2023]
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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] [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.
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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.
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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] [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.
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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.
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Exploring the Diversity and Novelty of Toxin Genes in Naja sumatrana, the Equatorial Spitting Cobra from Malaysia through De Novo Venom-Gland Transcriptomics. Toxins (Basel) 2019; 11:toxins11020104. [PMID: 30754700 PMCID: PMC6409529 DOI: 10.3390/toxins11020104] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 01/23/2019] [Accepted: 02/07/2019] [Indexed: 02/07/2023] Open
Abstract
The equatorial spitting cobra, Naja sumatrana, is a distinct species of medically important venomous snakes, listed as WHO Category 1 in Southeast Asia. The diversity of its venom genes has not been comprehensively examined, although a few toxin sequences annotated to Naja sputatrix were reported previously through cloning studies. To investigate this species venom genes’ diversity, de novo venom-gland transcriptomics of N. sumatrana from West Malaysia was conducted using next-generation sequencing technology. Genes encoding toxins represented only 60 of the 55,396 transcripts, but were highly expressed, contributing to 79.22% of total gene expression (by total FPKM) in the venom-glands. The toxin transcripts belong to 21 families, and 29 transcripts were further identified as full-length. Three-finger toxins (3FTx) composed of long, short, and non-conventional groups, constituted the majority of toxin transcripts (91.11% of total toxin FPKM), followed by phospholipase A2 (PLA2, 7.42%)—which are putatively pro-inflammatory and cytotoxic. The remaining transcripts in the 19 families were expressed at extremely low levels. Presumably, these toxins were associated with ancillary functions. Our findings unveil the diverse toxin genes unique to N. sumatrana, and provide insights into the pathophysiology of N. sumatrana envenoming.
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Venomics of Trimeresurus (Popeia) nebularis, the Cameron Highlands Pit Viper from Malaysia: Insights into Venom Proteome, Toxicity and Neutralization of Antivenom. Toxins (Basel) 2019; 11:toxins11020095. [PMID: 30736335 PMCID: PMC6410072 DOI: 10.3390/toxins11020095] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 01/23/2019] [Accepted: 01/30/2019] [Indexed: 12/18/2022] Open
Abstract
Trimeresurus nebularis is a montane pit viper that causes bites and envenomation to various communities in the central highland region of Malaysia, in particular Cameron’s Highlands. To unravel the venom composition of this species, the venom proteins were digested by trypsin and subjected to nano-liquid chromatography-tandem mass spectrometry (LC-MS/MS) for proteomic profiling. Snake venom metalloproteinases (SVMP) dominated the venom proteome by 48.42% of total venom proteins, with a characteristic distribution of P-III: P-II classes in a ratio of 2:1, while P-I class was undetected. Snaclecs constituted the second most venomous protein family (19.43%), followed by snake venom serine proteases (SVSP, 14.27%), phospholipases A2 (5.40%), disintegrins (5.26%) and minor proteins including cysteine-rich secretory proteins, L-amino acid oxidases, phosphodiesterases, 5′-nucleotidases. The venomic profile correlates with local (painful progressive edema) and systemic (hemorrhage, coagulopathy, thrombocytopenia) manifestation of T. nebularis envenoming. As specific antivenom is unavailable for T. nebularis, the hetero-specific Thai Green Pit viper Monovalent Antivenom (GPVAV) was examined for immunological cross-reactivity. GPVAV exhibited good immunoreactivity to T. nebularis venom and the antivenom effectively cross-neutralized the hemotoxic and lethal effects of T. nebularis (lethality neutralizing potency = 1.6 mg venom per mL antivenom). The findings supported GPVAV use in treating T. nebularis envenoming.
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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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 10/11/2018] [Accepted: 10/27/2018] [Indexed: 12/13/2022]
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Tan CH, Tan KY. Functional Application of Snake Venom Proteomics in In Vivo Antivenom Assessment. Methods Mol Biol 2019; 1871:153-158. [PMID: 30276739 DOI: 10.1007/978-1-4939-8814-3_11] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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.
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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
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Venom Proteome of Spine-Bellied Sea Snake ( Hydrophis curtus) from Penang, Malaysia: Toxicity Correlation, Immunoprofiling and Cross-Neutralization by Sea Snake Antivenom. Toxins (Basel) 2018; 11:toxins11010003. [PMID: 30583590 PMCID: PMC6356285 DOI: 10.3390/toxins11010003] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Revised: 12/14/2018] [Accepted: 12/19/2018] [Indexed: 11/16/2022] Open
Abstract
The venom proteome of Hydrophis curtus (synonym: Lapemis hardwickii) from Penang, Malaysia was investigated with nano-electrospray ionization-liquid chromatography tandem mass spectrometry (ESI-LCMS/MS) of the reverse-phase high-performance liquid chromatography (HPLC) venom fractions. Thirty distinct protein forms were identified as toxins from ten families. The three major protein families were phospholipase A2 (PLA2, 62.0% of total venom proteins), three-finger toxin (3FTX, 26.33%) and cysteine-rich secretory protein (CRiSP, 9.00%). PLA2 comprises diverse homologues (11 forms), predominantly the acidic subtypes (48.26%). 3FTX composed of one short alpha-neurotoxin (SNTX, 22.89%) and four long alpha-neurotoxins (LNTX, 3.44%). Both SNTX and LNTX were lethal in mice (intravenous LD50 = 0.10 and 0.24 μg/g, respectively) but the PLA2 were non-lethal (LD50 >1 μg/g). The more abundant and toxic SNTX appeared to be the main driver of venom lethality (holovenom LD50 = 0.20 μg/g). The heterologous Sea Snake Antivenom (SSAV, Australia) effectively cross-neutralized the venom (normalized potency = 9.35 mg venom neutralized per g antivenom) and the two neurotoxins in vivo, with the LNTX being neutralized more effectively (normalized potency = 3.5 mg toxin/g antivenom) than SNTX (normalized potency = 1.57 mg/g). SSAV immunorecognition was strong toward PLA2 but moderate-to-weak toward the alpha-neurotoxins, indicating that neutralization of the alpha-neurotoxins should be further improved.
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