Development of an anti-human EphA2 monoclonal antibody Ea2Mab-7 for multiple applications
Hiroyuki Satofuka, Hiroyuki Suzuki, Tomohiro Tanaka, Guanjie Li, Mika K. Kaneko, Yukinari Kato
Abstract
Ephrin type A receptor 2 (EphA2) binds to membrane-bound ligands, ephrin A1, A2, and A5, eliciting bidirectional signaling. This signaling regulates many physiological processes, such as tissue development, homeostasis, and regeneration. The dysregulation of the EphA2-ephrins axis contributes to various diseases, including cancers. The high expression of EphA2 is observed in various cancers, which promotes cancer malignancy, whereas its levels are relatively low in most normal adult tissues. Therefore, EphA2 is a promising target for cancer therapy. We developed anti-human EphA2 monoclonal antibodies in this study using the Cell-Based Immunization and Screening method. Among them, a clone Ea 2 Mab-7 (IgG 1 , κ) exhibited a high affinity and sensitivity in flow cytometry. The dissociation constant values of Ea 2 Mab-7 for CHO/EphA2 and MDA-MB-231 cells were determined as 6.2 ± 1.3 × 10 −9 M and 1.6 ± 0.4 × 10 −9 M, respectively. Furthermore, Ea 2 Mab-7 can detect endogenous EphA2 in Western blot and immunohistochemistry. Therefore, the Ea 2 Mab-7 is highly versatile for basic research and is expected to contribute to clinical applications, such as antibody therapy and tumor diagnosis. • EphA2 is a promising target of antibody therapy for tumors. • A novel anti-EphA2 monoclonal antibody, Ea 2 Mab-7, showed high affinity and specificity in flow cytometry. • Ea 2 Mab-7 is also available for western blot and immunohistochemistry. • Ea 2 Mab-7 is expected to aid the development of tumor diagnosis and therapy.