Snake Venom Proteomics, Immunoreactivity and Toxicity Neutralization Studies for the Asiatic Mountain Pit Vipers, Ovophis convictus, Ovophis tonkinensis, and Hime Habu, Ovophis okinavensis

Abstract

Snakebite envenomation is a serious neglected tropical disease, and its management is often complicated by the diversity of snake venoms. In Asia, pit vipers of the Ovophis species complex are medically important venomous snakes whose venom properties have not been investigated in depth. This study characterized the venom proteomes of Ovophis convictus (West Malaysia), Ovophis tonkinensis (northern Vietnam, southern China), and Ovophis okinavensis (Okinawa, Japan) by applying liquid chromatography-tandem mass spectrometry, which detected a high abundance of snake venom serine proteases (SVSP, constituting 40–60% of total venom proteins), followed by phospholipases A2, snake venom metalloproteinases of mainly P-III class, L-amino acid oxidases, and toxins from other protein families which were less abundant. The venoms exhibited different procoagulant activities in human plasma, with potency decreasing from O. tonkinensis > O. okinavensis > O. convictus. The procoagulant nature of venom confirms that consumptive coagulopathy underlies the pathophysiology of Ovophis pit viper envenomation. The hetero-specific antivenoms Gloydius brevicaudus monovalent antivenom (GbMAV) and Trimeresurus albolabris monovalent antivenom (TaMAV) were immunoreactive toward the venoms, and cross-neutralized their procoagulant activities, albeit at variably limited efficacy. In the absence of species-specific antivenom, these hetero-specific antivenoms may be useful in treating coagulotoxic envenomation caused by the different snakes in their respective regions.

Proteomics and immunocharacterization of Asian mountain pit viper (Ovophis monticola) venom

“…okinavensis . The pattern of dominant bands was most similar to the venom of O. tonkinensis found in China [ 10 ].…”

“…Among these three Ovophis spp., the most abundant proteins were of SVSP (35–53%), followed by PLA 2 (19–25%) and LAAO (5–17%). SVMP (11–19%) was detected at a lower percentage than in our venom [ 10 ]. Such venom variation in venom composition could would not only be attributed by speciation but also other factors including prey diversity reflecting different ecological habitats [ 11 ], snake sex, [ 17 ] and age [ 18 , 19 ].…”

“…The second most abundant enzyme was PLA 2 ranging from 19–26%. In addition, various non-enzymatic proteins and peptides including cysteine-rich secretory proteins (CRISP), venom nerve growth factor (VNGF), venom endothelial growth factor (VEGF), kunitz peptides (KUN) and C-type lectins/snaclecs (CTL) were recorded, in varying amounts [ 10 ]. However, variation in snake venom composition occurs not only among distinct species but also among different population of the same species, due to ecological niches as well as availability of preys [ 11 ].…”

Case Report: Symptoms and Prognosis of Trimeresurus gracilis Envenomation

“…12 Gloydius brevicaudus and T. albolabris antivenoms were immunoreactive against the venoms of Ovophis snakes and cross-neutralized their procoagulant activities, albeit with variable and limited efficacy. 13 Thai hemato polyvalent snake antivenom effectively neutralized the lethality of the venom of the common Southeast Asian viperid. 14 Snakes of the widespread genus Trimeresurus are responsible for numerous bites in Asia.…”

Case Report: Management of an Uncommon Crotaline Snakebite (Ovophis makazayazaya)

“…11,12,15 Because of the lack of a specific antivenom for Ovophis spp. envenomation, Tan et al 16 examined the immunoreactivity of four monovalent antivenoms [i.e., antivenom for Calloselasma rhodostoma (produced in Thailand), for D. acutus (produced in China), for Gloydius brevicaudus (produced in China), and for T. albolabris (produced in Thailand)] to the Stronger reactivity of the polyvalent antivenom to the venom than that of the monovalent antivenom was observed. However, neither in vitro nor in vivo neutralization tests were performed in that study.…”