Figure 1.

Shark immunization and screening of VNARs against TROP-2. (A) Determination of serum titers after immunization. (B) PCR analysis of randomly picked clones from the original library. (C) Poly-clonal ELISA identification of phages specifically recognizing TROP-2. (D) VNARs were identified from 288 clones bound specifically to TROP-2 after three rounds of bio-panning by monoclonal ELISA. (E) SDS-PAGE analysis of 5G8, 5E9, 5C10, 4B6, 4G3 and 5D2. (F) Affinity analysis of six positive sequences screened for TROP-2 by BLI. (G) ELISA analysis of VNARs 5G8, 5E9, and 5C10 for binding to TROP-2. (H) Sequence structures of three high-affinity VNARs targeting TROP-2. Data in (A), (C), and (G) are reported as the mean ± SD, n = 3 per group.