Preparation and in vitro studies of [I-125]IUDR-T101 antibody conjugate

Idoxuridine labeled with I-125 was conjugated to polylysine. This conjugate was then coupled to the carbohydrate side chains of T101 monoclonal antibo diy anti-CD5. The immunoreactivity, cell retention, cytotoxicity, and intra cellular localization of this conjugate was tested in CCRF-CEM cells (CD5 p ositive). The conjugate had 68% immunoreactivity. The retention of I-125 by CCRF-CEM cells was higher for the conjugate than for T101 directly labeled with I-125 and more of it localized in the nucleus than did the I-125 labe led T101. The I-125 IUDR-polylysine-T101 conjugate was move cytotoxic than the I-125-labeled T101. In conclusion, the conjugation of [I-125]IUDR to T1 01 is feasible, and preferential targeting of the I-125 to the nucleus is o btained.