Preparation and Testing of Human Compatible Serum Butyrylcholinesterase

"Exposure to organophosphates (OPs), in the form of nerve gas and insecticides poses an ever increasing military and civilian threat. In recent years exogenous administration of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) have beensuccessfully used as safe and efficacious prophylactic treatments due to their capacity to scavenge OPs in the blood before inhibition of the targeted endogenous AChE can occur. Importantly BChE has also been used for treating cocaine-overdosedindividuals and alleviating succinylcholine-induced apnea. However, while the currently used methods of native enzyme isolation from frozen plasma are effective on a laboratory scale, they are time consuming and expensive. These factors, coupled withpotential safety issues associated with the purification of proteins from human blood (i.e. hepatitis, HIV, prion contamination), highlight the importance of developing recombinant BChE technology as an alternate and parallel strategy for the commercialproduction. This Phase I application proposes to produce highly purified recombinant rhesus macaque BChE (rMaBChE) that exhibits chemical and functional properties similar to the native enzyme i.e. circulatory stability and no immunogenicity when injectedinto an homologous host. Administration of native Ma BChE into macaques results in long circulatory times and serves as an excellent system for elucidating rBChE expression technology and for comparing ho