Immunological cross reactivity & paraspecificity of the scorpion Heterometrus bengalensis antivenom.

Immunological cross-reactivity and paraspecificity of scorpion H. bengalensis antivenom were studied to find out the intergeneric therapeutic relationship between the venom of other scorpions in West Bengal Buthus tamulus, Lychas laevifrons and Heterometrus swammerdami. Of these scorpions, Buthus tamulus and Lychas laevifrons failed to show any cross reactivity. However, H. swammerdami venom showed cross-reactivity with H. bengalensis antiserum as revealed from immunogeldiffusion and immunoelectrophoresis. This antiserum protected H. swammerdami venom-induced lethality in mice, blocked the contractile response in smooth muscles and antagonised the venom-induced neuromuscular blockade in rat phrenic nerve diaphragm and chick biventer cervicis.

Comparative detoxification and protection of scorpion (Heterometrus bengalensis) venom by toxoid antiserum.

Comparative detoxification of scorpion venom by using different chemical agents was investigated. Detoxification by formalin showed the best optimum detoxifying agent. The formalin treatment resulted in 2.3% protein loss with 6-fold detoxification. This formal toxoid was immunogenic in rabbit giving high neutralizing antibodies as revealed from indirect haemagglutination test. Toxoid antiserum protected mice against the lethal action of venom. It also effectively antagonized the smooth muscle contractile response of venom, and venom-induced neuromuscular paralysis. This toxoid antiserum also protected the venom-induced cardiac arrest. The possibility of using this formal toxoid for antisera production and immunization for therapeutic use needs to be explored.

Pharmacological and immunological evaluation of scorpion (Heterometrus bengalensis) venom antiserum.

An antiserum was prepared for the first time against the venom of a common scorpion, H. bengalensis, by hyperimmunization of rabbit. This antiserum showed positive precipitin bands in immunogeldiffusion and immunoelectrophoresis. The serum showed a high titre value tested by indirect haemagglutination test. The antiserum developed in rabbit protected mice against the lethal action of the venom. Smooth muscle contractile response of venom on guinea pig ileum, and rat uterus was antagonized by the antiserum. This antiserum effectively antagonized the venom induced neuromuscular paralysis tested on rat phrenic nerve diaphragm and chick biventer cervices. Antiserum also protected the venom-induced cardiac arrest tested on isolated guineapig heart and auricle preparations.