IMMUNOLOGICAL STUDIES ON ANTISCORPION SERUM AND ANTIVENIN

Abstract

Preparation of polyvalent antiscorpion serum was carried out in horses against venom of the Iranian scorpions Mesobuthus eupeus, Odontobuthus doriae, and Scorpio maurus. In addition, six scorpion venoms from Androctonus crassicauda, Buthotus saulcyi, Hemiscorpius lepturus, Mesobuthus eupeus, Odontobuthus doriae, and Scorpio maurus were obtained by electrical stimulation and used in freeze-dried form. The anti-scorpion serum was purified and concentrated by enzyme digestion and examined for its in vivo neutralization in mice, as well as precipitation of antibodies in vitro by immunodiffusion technique. One reference antiscorpion serum, obtained from the Lister Institute (England), was used for comparison. One polyvalent anti-snakebite serum prepared at Razi Institute (Iran), was used for comparison of cross-neutralization against the Iranian scorpion venoms. The Iranian antiscorpion serum showed high neutralization capacity and strong precipitation reaction against its homologous venom, and low potency and weak precipitation reaction against the heterologous venoms. No protection but weak precipitation reaction against Androctonus crassicauda venom was observed: one ml serum neutralized 103 LD50 of Odontobuthus doriae, 35 LD50 of Mesobuthus eupeus or Buthotus saulcyi, 4 LD50 of Scorpio maurus, 3 LD50 of Hemiscorpius lepturus, but gave no protection for Androctonus crassicauda, in mice; 6, 6, 0, 6, 0 and 3 precipitation lines were observed ‘respectively’ by Ouchter-lony's technique. The reference serum was studied for its paraspecific action against the Iranian scorpion venoms; the serum showed some protection against the venoms. Relatively it was more effective for Mesobuthus eupeus, Buthotus saulcyi and odontobuthus doriae, and showed low protection against Androctonus crassicauda, Scorpio maurus, and Hemiscorpius lepturus. No precipitation reaction against Scorpio maurus and Mesobuthus eupeus venoms were observed. The polyvalent anti-snakebite serum showed some neutralization against Scorpio maurus, Mesobuthus eupeus and Hemiscorpius lepturus, but no precipitation reaction were observed. Antiscorpion sera appears to be specific, and demonstrates so me paraspecific action. Cross–neutralization within the different species, but with a varied geographical distribution is also weak.