In order to determine the capability of the gp41-specific antibody to bind capsid-incorporated antigen in a dose-dependent manner a dose-response ELISA assay was performed with anti-gp41 antibody. A single concentration of each of the following viruses: AdCMVGag, Ad5/HVR2-MPER-L15(Gag), or Ad5/ HVR2-MPER-L15DE1 was applied to ELISA plates, followed by the addition of serial dilutions of gp41 antibody. As predicted, the anti-gp41 antibody bound to Ad5/HVR2-MPER-L15(Gag) and Ad5/HVR2-MPER-L15DE1 in a dose dependent manner ( Figure 3B ). Our data suggest that the MPER epitope is presented within the hexon in its native conformation as it can be recognized by a monoclonal HIV neutralizing antibody.