| Envenomations induced by snakebites represent a significant public health issue in many regions of the world. According to World Health Organization, 2.5 million snake bites and 125 thousand deaths are reported each year. In China, 100 thousand people are bitten, 73 percent of whom are young and middle-aged adult. It is estimated that the fatality are between 5%-10%, and 25%-30% of victims are incapable of job due to the deformity caused by snake bites.Venoms are deadly cocktails, each comprising unique mixtures of peptides and proteins. Venom toxin disarranging the central and peripheral nervous systems, the cardiovascular and the neuromuscular systems, blood coagulation and homeostasis. And now it has been identified that snake venom metalloproteinases (SVMPs) play an important role in causing spontaneous systemic hemorrhage.Structural studies on the snake venom metalloproteinase have suggested they can be devided into four classes, PI to PIV. PI class are composed of a signal peptide, a metalloproteinase domain, 20-30kDa ; PII class have the metalloproteinase and a disintegrin domain, 30-50kDa; PIII class contain a cystein-rich domain in addition to the metalloproteinase domain and disintegrin-like domain, 50-80kDa and comparing with PIII class, PIV class contain additional C-type lectin domain joining by sulphur-sulphur bonds.Treatment of snake bites includes traditional (herbal) treatments and administration of antivenom. Herbal treatments are not encouraged because their unclear mechanism. Antivenom is the only specific antidote to snake bites and snake venom typically contains numerous diverse proteins of varying toxicity that are difficult to purify in sufficient amount for immunization. Conventional snake antivenom is created by injecting a small amount of the whole venom into an animal such as a horse, so the antivenom contains an immunoglobulin pool of unknown antigen specificity and known redundancy, which necessitates the delivery of large volumes of heterogonous immunoglobulin to the envenomed victim, thus increasing the risk of anaphylactoid and serum sickness adverse effects. Hence, we identify the potent antigenic epitopes in the snake venom, validate by animal experiment, and the positive control is natural antigenic epitopes derived from the RNA of gland of snake.The venom of Deinagkistrodon acutus was choosen, for it was strongly hemorrhagic. We BLAST all SVMPs sequences of the snake, and antigenic epitopes were computerized by Jameson-Wolf and Clustal X. DNA sequence of antigenic eptiopes were synthesized, connected to the eukaryotic expression vector pIRESneo, then, immunized the mice for the toxin-targeted antibody. The validity of DNA immunization was evaluated by ELISA, neutralization of venom hemorrhagic activity and venom attacking test, PIII SVMP as positive control.In conclusion, we demonstrated that there was no significant difference in capacity of antibody-inducing between synthesized DNA sequence of antigenic eptipoes and PIII SVMP. The ELISA results showed that the antigen could be detected when the antisera were diluted to 1/100, the results of neutralization of venom hemorrhagic activity indicated they both could neutralize haemorrhage induced by snake venom, and the protective rates of venom attacking test were both 80%. Thus, the identification of antigenic eptiopes by bioinformatics approach was feasible and effective. Our projects highlight the value of the bioinformatics method to prepare the multi-DNA vaccine for antivenom.
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