Biokinetics of the monoclonal antibodies MOv 18, OV 185 and OV 197 labelled with I-125 according to the m-MeATE method or the iodogen method in nude mice with ovarian cancer xenografts

The biodistribution of the radiolabelled monoclonal antibodies MOv18, OV185 and OV197 in nude mice with subcutaneous tumours of the human ovarian canc er cell line OVCAR3 was investigated. The early uptake of MOv18 (1-24 h) an d the uptake in relation to tumour size were also studied. The antibodies w ere labelled with I-125 according to the lodogen method or the m-MeATE meth od, the latter also bring suitable for labelling with (211)Astatine. The tu mour/blood ratio and the localization index for Mov 18 72 h after antibody injection were 2.21 +/- 0.25 and 4.62 +/- 1.27, respectively. This is signi ficantly higher than for the other two specific antibodies. The early tumou r uptake of MOv18 was low with a tumour/blood ratio of 0.23 +/- 0.04 after 6 h, and the uptake was higher in small tumours. The two labelling methods were found to be equivalent. We conclude that MOv18 labelled according the m-MeATE method should be suitable for further therapeutic studies with (211 )Astatine in nude mice.