Background
The membrane-proximal external region (MPER) of HIV-1 gp41, which is thought to be involved in the viral fusion process, is an important target for an HIV vaccine. Two broadly neutralizing monoclonal antibodies, 2F5 and 4E10, bind to adjacent linear epitopes in the gp41 MPER. However, attempts to design immunogens that elicit a neutralizing antibody response against this region have had limited success.