Reduction of Purification Time of Polyspecific Equine F(ab´)۲ Antivenom against Scorpion Envenomation

Background and Aims: In this study we improved the purification of immunoglobulins from equine antiserum raised against the venom of ۶ types of scorption species. Caprylic acid (octanoic acid), a fatty acid, was found to have no effect on the activity of the enzymes pepsin, which is used in antivenom purification to digest Fc fragment of immunoglobulins to obtain F(ab´)۲. Materials and Methods: A new method was developed for the production of F(ab´)۲ antivenom whereby whole equine antiserum was mixed with equal amount of ۰.۱۵ M HCl and pH ۳.۴ with pepsin ۶۶۰ mg/L of diluted antivenom and incubated for ۴ h at ۳۷°C. After digestion the pH were brought to ۴.۸ with sodium hydroxide solution (۱.۵ M) and then ۱.۵% caprylic acid and ۱۰% ammonium sulfate was added and mixed for ۶۰ minutes and passed through filter paper. Results: Caprylic acid caused precipitation of albumin, and ammonium sulfate reduced turbidity of solution, resulting in a reduced protein load presented to the digestion enzymes culminating in substantial reductions in processing time. Conclusions: The equine F(ab´)۲ obtained using these novel caprylic acid methods were comparable in terms of yield, purity and specific activity to those obtained by multi-step and time consuming conventional salt fractionation with ammonium sulfate.

کلیدواژه ها:

Antiscorpion venom ، Caprylic acid ، Equine ، Scorpion ، اسب ، کاپریلیک اسید ، F(ab´)۲ ، پپسین ، جداسازی اجزای آنتی ونوم ، رسوب آمونیم سولفات