Naive female C57BL/6-CEA-Tg mice were injected concurrently with Ad-CEA (subcutaneous, s.c.) and N-803 (s.c.). Spleens were collected 0, 8, 18, 24, 48, and 72 hours after the injection. Frequency, total cell number, and mean fluorescence intensity (MFI) of GITR and OX40 expression on (A-B) CD4+ and (C-D) CD8+ splenocytes were analyzed via flow cytometry. Error bars represent mean±SEM. These studies were repeated 3–4 times with similar results.