Predicting CD137 upregulation on NK cells in patients receiving monoclonal antibody therapy

Background Monoclonal antibody (mAb) therapy-has changed the natural history of patients with B cell lymphomas, breast cancer, and head and neck cancers. However, response rates are suboptimal, highlighting the need to enhance mAb activity. Combining a tumor targeting mAb with a second antibody that activates natural killer (NK) cells may improve the therapeutic effects of mAbs. Engagement of the Fc receptor (FcR) on NK cells by mAbs coating tumor cells has been previously shown to enhance their expression of CD137 [1-3]. We conducted preliminary analyses as a first step toward developing a nomogram to predict CD137 up-regulation following therapy with mAb.