Cell kinetic analysis of human tumor xenografts using anti-bromodeoxyuridine monoclonal antibody

The cell kinetics of human tumor xenografts serially transplanted into nude mice was examined using bromodeoxyuridine (BrdU) and anti-BrdU monoclonal antibody. After various doses of BrdU were given intraperitoneally into tumor bearing nude mice, the tumors were resected and stained immunohistochemically, using the anti-BrdU monoclonal antibody. The number of stained cells was demonstrated as the labeling index (LI). The optimal condition for BrdU staining was assumed to be 300 mg of BrdU per kg followed by an incubation period of one hour. Since the LI by BrdU closely correlated with that in autoradiography by 3H-TdR, this method is more useful and safer than the conventional autoradiographic study for investigating clinical cell kinetic analysis, as there is no need to use potentially hazardous radioactive compounds and the period of assay is shorter.