Determination of MIL50, a humanized antibody, in different tissues of rats by a sandwich enzyme-linked immunosorbent assay / 军事医学

ABSTRACT

Objective To develop a sandwich enzyme-linked immunosorbent assay ( ELISA) for the determination of a humanized antibody MIL50.Methods RiVax, a mutant of RTA (a chain of ricin) expressed in E.coli, was used as the coating protein.Horseradish peroxidase (HRP) labeled IgG of goats against humans was used to determine MIL 50 captured by RiVax coated on the plate.Results Compared with ricin, RiVax could bind well with MIL50,indicating it could be used as a coating protein to determine MIL50 instead of holotoxin.Using this method, the detective limit of MIL50 in PBST (PBS containing 0.1%Tween 20) could be as low as 0.030 mg/L.The absorbance value of ELISA for MIL50 in the ser-um and homogenate of the liver , spleen, lung, kidney, muscle of rats was lower than that in PBST .Conclusion The sandwich ELISA is a sensitive method for the analysis of distribution of MIL 50 in rat tissues.