RADIOIMMUNODETECTION OF HUMAN CERVICAL-CARCINOMA XENOGRAFT BY IN-111-LABELED MONOCLONAL-ANTIBODY MAB CX-99

Radioimmunodetection (RAID) is more sensitive and specific than conven tional diagnostic methods. In this study, a monoclonal antibody agains t cervical carcinoma antigen, MAb Cx-99, was labeled with (111)Indium (In-111). This immunoconjugate was intravenously injected into athymic nude mice bearing cervical squamous cell carcinoma (SCC) xenografts. The tissue distribution study showed that the xenograft tumor had high er binding activity than most other tissues after 48 h from injection, demonstrated by localization ratio of tumor or tissues (c.p.m./g) aga inst blood (c.p.m./g). However, this localization ratio was also high in the liver, spleen and kidney. The imaging study by immunoscintigrap hy also showed that the tumor and liver were distinct from other backg round tissues 2 days after injection. This preliminary study showed th at In-111-labeled MAb Cx-99 may have potential for RAID of cervical ca ncer, especially for tumors in the pelvis.