Figure 6.

Oligoclonal band (OCB) peptides reveal signs of affinity maturation. Shown is an immunoglobulin G (IgG) heavy chain variable germline gene 4–39–derived, truncated IgG heavy chain variable region with OCB peptides identified by mass spectrometry in isoelectric focusing gel slices A, B, D, J, and K (see Fig 4; Supplementary Table S3) in Patient MS-3’s cerebrospinal fluid. Shaded in light gray are aligned amino acid sequences of identified OCB peptides reflective of ongoing affinity maturation in a B-cell cluster contributing to OCB production in Patient MS-3. Heavy chain CDR2 region (H-CDR2) and H-CDR3 are in gray frames. Dots indicate identity with the consensus sequence (top).