El-Yamany Mohammed F, Samy Esraa M, Salama Walaa H, Shaaban Esmat A, Abd El-Latif Hekma A
Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Egypt.
Department of Drug Radiation Research, National Center for Radiation Research and Technology, Atomic Energy Authority, Cairo, Egypt.
Toxicon. 2020 Dec;188:108-116. doi: 10.1016/j.toxicon.2020.10.013. Epub 2020 Oct 13.
Echis pyramidum (Epy) is a venomous snake belongs to Viperidae family; it causes fetal coagulopathy systemic effects and death. Searching for more effective and safe antivenom is mandatory for viper bites treatment. Proteases are the most lethal components in viper venom inducing hemorrhage, edema and coagulation problems. Thus, the study aims to evaluate the potency of the prepared antisera and their neutralizing properties against the biological activities induced by whole Epy venom individually. Echis pyramidum metalloprotease enzyme (60 kDa) was purified using size-exclusion followed by DEAE-ion exchange chromatography. The purified Epy metalloprotease enzyme (SVMP) was detoxified with 1.5 kGy gamma rays from cobalt gamma cell and used for immunization. 1.5 kGy irradiated Epy metalloprotease (SVMPi) showed less lethal activity (LD) compared to the corresponding native immunogen. The prepared antisera boosted against whole Epy venom (WV), 1.5 kGy irradiated whole Epy venom (WVi), SVMP and SVMPi were tested for neutralization of lethality and biological activities induced by Epy venom. The antibodies elicited against WVi and SVMPi were 30,000 and 20,000 EU, respectively. The anti-SVMPi serum showed the highest neutralization of lethality (ED) compared to the other prepared antisera. In addition, it prolonged the clotting time from 49.0 ± 2.5 to 176.2 ± 1.4 s. Furthermore, it demonstrated a highly neutralizing activity against edema induction and hemorrhage of Epy venom by 66.8% and 94.3%, respectively compared with the other prepared antisera. These findings would encourage further studies for using gamma irradiated purified fraction(s) from different snake venoms as safe antigen(s) to produce more effective antivenoms.
锯鳞蝰（Epy）是一种属于蝰蛇科的毒蛇；它会导致胎儿凝血障碍、全身效应甚至死亡。寻找更有效、更安全的抗蛇毒血清对于蝰蛇咬伤的治疗至关重要。蛋白酶是蝰蛇毒液中最具致死性的成分，可引发出血、水肿和凝血问题。因此，本研究旨在评估所制备抗血清的效力及其针对锯鳞蝰全毒液单独诱导的生物活性的中和特性。使用尺寸排阻色谱法，随后进行DEAE离子交换色谱法，对锯鳞蝰金属蛋白酶（60 kDa）进行纯化。纯化后的锯鳞蝰金属蛋白酶（SVMP）用来自钴γ细胞的1.5 kGyγ射线进行解毒，并用于免疫。与相应的天然免疫原相比，1.5 kGy辐照的锯鳞蝰金属蛋白酶（SVMPi）显示出较低的致死活性（LD）。对针对锯鳞蝰全毒液（WV）、1.5 kGy辐照的锯鳞蝰全毒液（WVi）、SVMP和SVMPi制备的抗血清进行测试，以中和锯鳞蝰毒液诱导的致死性和生物活性。针对WVi和SVMPi产生的抗体效价分别为30,000和20,000 EU。与其他制备的抗血清相比，抗SVMPi血清显示出最高的致死性中和能力（ED）。此外，它将凝血时间从49.0±2.5秒延长至176.2±1.4秒。此外，与其他制备的抗血清相比，它对锯鳞蝰毒液诱导的水肿和出血分别表现出66.8%和94.3%的高度中和活性。这些发现将鼓励进一步研究，使用来自不同蛇毒的γ射线辐照纯化组分作为安全抗原，以生产更有效的抗蛇毒血清。
