MPL-A adjuvant embedded in them. B: ELISA endpoint titer of the 2F5 epitope peptide (SP62 peptide) specific responses in guinea pigs sera from different bleeds. C: The 2F5 epitope peptide (SP62 peptide) specific responses of guinea pigs sera determined by SPR are shown as a function of post-bleed number. P1-P11, post- immune bleeds 1-11. D: SPR sensogram displaying the compar- ison of 2F5 epitope peptide (SP62 peptide) specific binding of guinea pig 1375 sera from different bleeds with 10mg/ml 2F5 mAb is shown as representative data. E: Epitope mapping of post- immune bleed 6-11 of guinea pig 1375 is shown in comparison to 2F5 mAb. The normalized binding shown is the ratio between binding responses of sera to the alanine scanning mutant peptides and WT 2F5 epitope peptide SP62. The dotted circle highlights the mapping of MPER specific responses in guinea pig 1375 sera to D664KW666 residues as did 2F5 mAb. Data is representative of References 1. 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(2005) Cardiolipin polyspecific autoreactivity in two broadly neutralizing HIV-1 antibodies. Science 308: 1906–1908. PLoS ONE | www.plosone.org 13 November 2011 | Volume 6 | Issue 11 | e27824