Evaluation of a novel monoclonal antibody mAb109 by immuno-PET/fluorescent imaging for noninvasive lung adenocarcinoma diagnosis

Monoclonal antibodies are believed to be magic bullets and hold great potential for lots of biological process. About 100 mu g of mAb109 was expressed in 5x10(6) cells after 10 days' immunization. Cu-64-NOTA-mAb109 was synthesized with the specific activity of 0.74MBq/mu g and high in vitro stability. The binding affinity of Cu-64-NOTA-mAb109 in A549 cells was determined to be 29.64nM. Cu-64-NOTA-mAb109 displayed prominent tumor accumulation from 2h to 60h p.i. (9.34 +/- 0.67 %ID/g). NIRF imaging of Cy5.5-mAb109 showed high accumulation till 9 days p.i., while tumors nearly can not be observed in negative groups, which was confirmed by autoradiography. Immunohistological study confirmed that mAb109 had strong and specific capacity to bind lung adenocarcinoma (concentration to 58nM). Our study demonstrated mAb109 was a new platform for the development of novel agent for lung adenocarcinoma noninvasive imaging. The resulted Cu-64-NOTA-mAb109/Cy5.5-mAb109 show favorable imaging properties/specificity for A549 tumor and high sensitivity to human lung adenocarcinoma tissues.