A group led by Professor Shunichiro Kawabata of Kyushu University has succeeded in preparing proteins involved in body fluid coagulation of horseshoe crabs in collaboration with Seikagaku Corporation.It is a protein that plays an important role in detecting a substance called lipopolysaccharide that causes shock symptoms when mixed with drugs.
When bacteria such as Escherichia coli and Salmonella invade the human body, the immune defense reaction begins by recognizing a substance called lipopolysaccharide on the surface.However, since lipopolysaccharide itself is widely present in the environment, it can cause an excessive immune reaction due to contamination with injections, etc., and in severe cases, it may cause shock symptoms.To prevent this, Limulus reagent made from the blood of Atlantic horseshoe crab is used all over the world as a test drug to check for the presence of lipopolysaccharide.It utilizes the reaction between lipopolysaccharide and Limulus reagent to coagulate.However, in the future, there is a concern that the reagent will be insufficient due to the decrease in the horseshoe crab population, so it is required to artificially produce the reagent.
Two proteins, factor B and factor C, are mainly involved in the coagulation of horseshoe crab body fluids. The coagulation reaction begins when factor C acts on factor B to activate it.In previous studies, we succeeded in artificially preparing factor C, but this time we also succeeded in preparing factor B for the first time.It was also found to have the same effect as the natural B factor.
A series of studies has made it possible to artificially prepare two important factors.In the future, we will continue to work with Seikagaku Corporation on research toward the practical application of highly sensitive reagents using these factors.
