Immunoreactivity and neutralization study of Chinese Bungarus multicinctus antivenin and lab-prepared anti-bungarotoxin antisera towards purified bungarotoxins and snake venoms

Abstract

Bungarus multicinctus is the most venomous snake distributed in China and neighboring countries of Myanmar, Laos, north Vietnam and Thailand. The high mortality rate of B. multicinctus envenomation is attributed to the lethal components of α-, β-, γ- and κ- bungarotoxins contained in the venom. Although anti-B. multicinctus sera were produced in Shanghai, Taiwan and Vietnam, the most widely clinic used product was term as B. multicinctus antivenin and manufactured by Shanghai Serum Bio-technology Co. Ltd. In the present investigation, high purity α-, β- and γ-bungarotoxins were separately isolated from B. multicinctus crude venom. Rabbit anti- α-, β- and γ-bungarotoxin antisera were prepared by common methods, respectively. LD50 values of α-, β- and γ-bungarotoxins were systematically determined via three administration pathways (intraperitoneal, intramuscular and intravenous injections) in Kunming mice. LD50 values of β-bungarotoxin were closely related with injection routines but those of both α- and γ-bungarotoxins were not dependent on the injection routines. Commercial B. multicinctus antivenin showed strong immunoreaction with high molecular weight fractions of the B. multicinctus but weakly recognized low molecular weight fractions like α- and γ-bungarotoxins. Although B. multicinctus antivenin showed immunoreaction with high molecular weight fractions of Bungarus fasciatus, Naja atra, Ophiophagus hannah venoms but the antivenin only demonstrated animal protection efficacy against O. hannah venom. These results indicated that the high molecular weight fractions of the O. hannah played an important role in venom lethality but those of B. fasciatus and N. atra did not have such a role.

In Vitro Neurotoxicity of Chinese Krait (Bungarus multicinctus) Venom and Neutralization by Antivenoms

“…A recent study examined the efficacy of B. multicinctus antivenom against isolated toxins (i.e., α-, β- and γ-bungarotoxins) from B. multicinctus venom using mice (i.e., an LD 50 assay and determining ED 50 values) [ 34 ]. These authors confirmed that β-bungarotoxin was the most ‘lethal’ component with LD 50 values of 0.004 μg/g (i.p), 0.015 μg/g (i.m) and 0.007 μg/g (i.v.).…”

“…These authors confirmed that β-bungarotoxin was the most ‘lethal’ component with LD 50 values of 0.004 μg/g (i.p), 0.015 μg/g (i.m) and 0.007 μg/g (i.v.). Interestingly, an examination of the immunoreactivity of the antivenom, using ELISA, indicated that the antivenom showed good neutralizing capacity against the crude B. multicinctus venom but weak immunoreactivity against α-and γ-bungarotoxins [ 34 ]. In addition, the immunoreactivity of the antivenom was 2.5 times higher against the whole venom than β-bungarotoxin [ 34 ].…”

“…Interestingly, an examination of the immunoreactivity of the antivenom, using ELISA, indicated that the antivenom showed good neutralizing capacity against the crude B. multicinctus venom but weak immunoreactivity against α-and γ-bungarotoxins [ 34 ]. In addition, the immunoreactivity of the antivenom was 2.5 times higher against the whole venom than β-bungarotoxin [ 34 ]. Therefore, even with early clinical administration, the antivenom is likely to display varying efficacy against key toxins.…”

Development of sandwich ELISA and lateral flow assay for the detection of Bungarus multicinctus venom

“…A snakebite epidemiology survey data from the Guangxi Autonomous Region, an epicenter for snakebite in mainland China, carried out by Guangxi Medical University, showed that the lethality rate for BM bites was about 5%, ranking as second only to that of Ophiophagus hannah bites in the past decade [ 8 ]. BM represents the most virulent snake inhabiting in mainland China owing to its high mortality rate [ 9 ]. The other three common Elapidae snake species, FS, NA, and OH, have overlapping activity zones in southern China and neighboring countries [ 10 ].…”

Network Pharmacological Study on the Mechanism of Cynanchum paniculatum (Xuchangqing) in the Treatment of Bungarus multicinctus Bites

“…Bungarus multicinctus is one of the top ten venomous snakes in China. Its venom is mainly neurotoxin-based [ 3 ], containing α -, β -, and γ -bungarotoxins (BGTs) [ 4 , 5 ]. Bungarus multicinctus bites cause neuromuscular symptoms, including ptosis, mydriasis, ophthalmoplegia, mandibular weakness, neck muscle paralysis, limb paralysis, respiratory muscle paralysis, respiratory failure, and even death [ 6 , 7 ].…”