July 18, 2011 -- Aliquots of snake venom are vital to the production of life-saving antivenoms. Scientists at the University of Liverpool, UK, are using a METTLER TOLEDO XP205 balance for critical processes in the research and manufacture of antivenom for West Africa.
With over 600 known species of venomous snakes worldwide, snakebite-related deaths continue to be an issue today. The risk of dying from a snakebite is greatest in rural areas of Africa and Asia, where the availability of antivenom and other appropriate treatments is lowest and the cost and complexity of antivenom manufacture are major obstacles to improving outcomes for snakebite victims. These high costs have meant that some regions, particularly in West Africa, have no access to potentially life-saving antivenoms.
The Alistair Reid Venom Research Unit (ARVRU) is part of the Liverpool School of Tropical Medicine (LSTM) at the University of Liverpool, UK, and is one of the world’s foremost centers for the development of snake antivenom. Founded in 1973, the Unit investigates the clinical and biological effects of snake venoms, as well as developing new antivenoms based on antibody technologies. A key goal of ARVRU’s ongoing research is to improve accessibility to these life-saving medicines through development of broad-spectrum antivenoms, which are effective against a range of different snake venoms.
Creation of affordable antivenoms, which are effective against the most dangerous snake toxins in a particular geographical region, relies on having access to a renewable supply of snake venom, and the LSTM Herpetarium is key to this. The Herpetarium is a UK Home Office accredited and inspected experimental animal facility housing more than 200 specimens of some of the world’s most dangerous snakes, including a large number of haemotoxic vipers and neurotoxic elapids from Africa. Under the expert eye of herpetologist Paul Rowley, venom is extracted from these snakes and freeze-dried. The valuable dried samples are then precisely weighed and aliquoted using an XP205 Balance. These samples are then used to gradually immunize horses or sheep, whose bodies then produce large quantities of antibodies to the venom toxins. It is these antibodies that form the basis of antivenoms. The weighing process must be rigorously controlled to ensure accurate dosing of venom, maximizing antibody production while avoiding harm to the animal. Dr Rob Harrison, Head of the ARVRU, said: “The ability to accurately measure amounts of venom and associated laboratory reagents is a key requirement of our scientific and clinical activities. The METTLER TOLEDO balance was chosen for its accuracy, reliability and flexibility in the hands of different members of the lab team.”
Using this method, the ARVRU works closely with antivenom producers in Wales and Costa Rica to supply antivenom to West Africa, where internationally coordinated supply of antivenom ceased at the turn of the millennium due to high costs and lack of demand. As part of this charitable venture, antivenom producers have used their spare capacity with material supplied by the ARVRU to provide over 25,000 vials of antivenom in the last four years, equating to almost 12,500 lives saved!