CD44v6-Targeted Imaging of Head and Neck Squamous Cell Carcinoma: Antibody-Based Approaches

Figure 2

Amino acid sequence of the human CD44v6 exon and antibody epitopes. Antibodies U36 and BIWA 1 target overlapping epitopes in the v6 region [5, 6]. Recombinant Fab-fragment AbD15179 was generated using a peptide that overlaps with the epitopes of U36 and BIWA 1 [7]. CD44v6-specific scFvs recognize an epitope in the same region (Haylock et al. [8]). It is noticeable that murine CD44v6 has a low homology with the human sequence in the region where common antibody epitopes overlap, which is indicated in the alignment of a 14-residue region from the two species.