Comparison of a mouse and a novel human scFv-SNAP-auristatin F drug conjugate with potent activity against EGFR-overexpressing human solid tumor cells.

Antibody-drug conjugates (ADCs) can deliver toxins to specific targets such as tumor cells. They have shown promise in preclinical/clinical development but feature stoichiometrically undefined chemical linkages, and those based on full-size antibodies achieve only limited tumor penetration. SNAP-tag technology can overcome these challenges by conjugating benzylguanine-modified toxins to single-chain fragment variables (scFvs) with 1:1 stoichiometry while preserving antigen binding.

Efficient targeting of CD13 on cancer cells by the immunotoxin scFv13-ETA' and the bispecific scFv [13xds16].

Purpose: Treatment of cancer using standard chemotherapy still offers a poor prognosis combined with severe side effects. Novel antibody-based therapies have been shown to overcome low efficiency and lack of selectivity by targeting cancer-associated antigens, such as aminopeptidase CD13.

Methods: We isolated a high-affinity CD13-specific single-chain fragment variable (scFv13) from a phage display library of V-genes from mice immunized with soluble antigen.

Fine Tuning Antibody Conjugation Methods using SNAP-tag Technology.

Background: Targeted imaging and therapy (theranostics) is a promising approach for the simultaneous improvement of cancer diagnosis, prognosis and management. Therapeutic and imaging reagents are coupled to tumor-targeting molecules such as antibodies, providing a basis for truly personalized medicine. However, the development of antibody-drug conjugates with acceptable pharmaceutical properties is a complex process and several parameters must be optimized, such as the controlled conjugation method and the drug-to-antibody ratio.

CD64-directed microtubule associated protein tau kills leukemic blasts ex vivo.

Fc gamma receptor I (FcγRI, CD64) is a well-known target antigen for passive immunotherapy against acute myeloid leukemia and chronic myelomonocytic leukemia. We recently reported the preclinical immunotherapeutic potential of microtubule associated protein tau (MAP) against a variety of cancer types including breast carcinoma and Hodgkin's lymphoma. Here we demonstrate that the CD64-directed human cytolytic fusion protein H22(scFv)-MAP kills ex vivo 15-50% of CD64+ leukemic blasts derived from seven myeloid leukemia patients.