Consensus sequence analyses and schematic representation of the conformational fibril-associated epitope recognized by mAb 11-1F4. (a) Comparison of Vκ4 with non-κ4 germ line consensus sequences (bolded residues are hydrophobic.). Abbreviations used in consensus sequences are: h, hydrophobic (A, C, F, I, L, M, V); o, S or T; p, polar (D, E, G, H, K, N, P, Q, R, S, T, W, Y); s, small residues (A, C, D, G, N, P, S, T, V), and u, minute residues (A, C, G, S). Consensus sequences were determined from VL germline sequences using CONSENSUS (http://us.expasy.org/tools/) analysis of CLUSTALW (28) multiple aligned sequences with 70% threshold. (b) Proposed model for the conformational epitope recognized by 11-1F4 involves a rearrangement of the first 9 VL residues centered on a cis-proline type VI β-turn or touch-turn induced by partial denaturation via surface adsorption or by fibrillogenesis. The N-terminal 15 residues are bolded.