Immunologic methods targeting the HA domain demonstrate that H1299, H460, and A549 cells express HA-SSTR2 after in vitro infection with Ad-CMV-HA-hSSTR2. In vitro HA-hSSTR2 expression by H1299, H460, and A549 cells with and without in vitro infection with Ad-CMV-HA-hSSTR2 using antibodies targeting the HA-domain was determined. (A) Immunofluorescent images of H1299, H460, and A549 cells without infection (a–c) or infected with Ad-CMV-HA-hSSTR2 (d–f). (B) ELISA of H1299, H460, and A549 cells with or without Ad-CMV-HA-hSSTR2 infection. Error bars represent SD of triplicate samples (*p < 0.05, uninfected cells vs. Ad-CMV-HA-hSSTR2 infected cells). (C) Western blots of H1299, H460, and A549 cells with or without Ad-CMV-HA-hSSTR2 infection. Cell protein extracted from cell lines was loaded at 20 μg per lane.