FIGURE 3.
N-terminal heterogeneity of Aβ peptides in 5XFAD and FAD42 mice. Mass spectra of immunoprecipitated Aβ peptides from the brains of mice using pan-Aβ antibodies 6E10 and 4G8 (A and B; used as a mix) and the N-terminal-specific antibody 1–57 (C) recognizing both pyroglutamate AβpE3 and unmodified Aβ3 peptides. A, the dominant fraction in 5XFAD and FAD42 mice was Aβ1–42, followed by Aβ1–40, AβpE3–42, Aβ4–42, AβpE3–40, and Aβ3–42. B, there was no significant difference in the pattern between 5XFAD and FAD42 mice. C, using 1–57 for IP-MS, N-terminal truncated AβpE-42 was the major peptide detected in 5XFAD, FAD42, and TBA42. No Aβ was detected in WT mice.