Evaluation of human major histocompatibility complex class I chain-related A as a potential target for tumor imaging

To investigate the feasibility of using human major histocompatibility complex class I chain-related A (MICA) as a target for tumor imaging diagnosis, 10C6, a monoclonal antibody (mAb) that specifically recognizes MICA in vitro, was labeled with 99mTc (technetium) and administered into mice bearing MICA-positive human ovarian epithelial carcinoma line SKOV3. Measurement of organ-specific radioactivity showed that tumor accumulated radioactivity continuously, while the uptake in the other organs decreased over time. Scintigram showed that the tumor became clearly visible at 24 h post-injection of radio-labeled 10C6 mAb. These results suggest that MICA is a promising target for tumor imaging and mAb 10C6 may be used clinically for early tumor diagnosis.