Abstract: Provided herein are, inter alia, antibody binding domains for cluster of differentiation 3 T cell receptor (CD3), antibody binding domains for epidermal growth factor receptor (EGFR), cleavable linker sequences, and protease-activatable bispecific fusion proteins such as protease-activatable T cell engagers, as well as uses and methods of treatment.

Abstract: Provided herein are, inter alia, antigen-binding molecules with binding specificity to cluster of differentiation 3 T cell receptor (CD3), antigen-binding molecules with binding specificity to prostate-specific membrane antigen (PSMA), cleavable linker sequences, and protease-activatable bispecific fusion proteins such as protease-activatable T cell engagers, as well as uses and methods of treatment.

Abstract: Described herein are methods for assessing likelihood of response of subjects to activatable therapeutic agents and compositions, kits, and methods of preparing and using activatable therapeutic agents. Also described herein are methods for assessing likelihood of response of subjects to activatable therapeutic agents. In some cases, the activatable therapeutic agents of the compositions, kits, and methods disclosed herein can comprise a mammalian protein-derived sequence.

Abstract: Disclosed herein are polypeptides, and methods of making and using such polypeptides, that comprise a bispecific antibody construct covalently linked to an extended recombinant polypeptide comprising a barcode fragment releasable from said polypeptide upon digestion by a protease, and a Release Segment that can be proteolytically cleaved wherein said cleavage releases the bispecific antibody construct from the extended recombinant polypeptide.