Fig. 2

Binding of Aβ isoforms to DEAE purified molecules including brevican. a. Western blot of Aβ isoforms used in binding assay to DEAE products in “b”. b. Solid phase, dose-dependent, binding of Aβ1-42 isoforms (monomeric, oligomeric and fibrillar) and Aβ(1–16) to DEAE purified molecules. The mean EC50s (n = 5 binding assays) for multiple conformational Aβ binding to DEAE purified brain protein was evaluated using one way ANOVA followed by Tukey’s multiple comparison test. EC50 for monomeric, oligomeric and fibrillar Aβ1-42 is significantly lower compared to the EC50 for Aβ1-16; (p < 0.05). c. Immunoprecipitation of brevican with mouse anti-Aβ 4G8 after soluble binding to DEAE product. Western blot was performed with mouse anti-brevican antibody. Lane identities: lane 1 DEAE extract only; lane 2 fibrillar Aβ only; lane 3 4G8 antibody only; lane 4 DEAE extract + monomeric Aβ; lane 5 DEAE extract + oligomeric Aβ; lane 6 DEAE extract + fibrillar Aβ. Anti-Aβ 4G8 pulled down brevican bound to oligomeric (lane 5) and fibrillar Aβ (lane 6). Lower molecular weight bands correspond to heavy and light IgG chains. Although all three isoforms of Aβ1-42 bound to brevican, binding to monomeric Aβ was markedly lower than binding to oligomeric and fibrillar Aβ