Establishment of a Novel Anti-Human Cadherin 13 Monoclonal Antibody (Ca₁₃Mab-4) Utilizing CBIS Method

Cadherin 13 (CDH13), also known as T-cadherin or H-cadherin, is a member of the cadherin superfamily. CDH13 is anchored to the plasma membrane via glycosylphosphatidylinositol. CDH13 plays an essential role in the development of the heart and nervous systems, including the brain. Many reports have identified CDH13 as a risk factor for neurodevelopmental disorders. Furthermore, CDH13 has been shown to be expressed in numerous cancers, but its role as a cancer-promoting or -suppressing factor remains unclear. Therefore, the development of highly sensitive and specific anti-CDH13 monoclonal antibodies (mAbs) is necessary to elucidate the biological and pathological functions of CDH13. In this study, we established a novel anti-human CDH13 mAb (clone Ca₁₃Mab-4) using the Cell-Based Immunization and Screening (CBIS) method. Ca₁₃Mab-4 can be used for flow cytometric analysis. Ca₁₃Mab-4 binds specifically to CDH13 and not to other cadherin family members. The dissociation constant values of Ca₁₃Mab-4 for CDH13-overexpressed CHO-K1 and U87MG glioma cells were determined as 2.5 (± 0.6) x 10^-8 M and 8.9 (± 2.1) x 10^-9 M, respectively. Furthermore, Ca₁₃Mab-4 clearly detected CDH13 in the western blot and immunohistochemistry of cell sections. Therefore, the Ca₁₃Mab-4, established by CBIS method, could be a valuable tool for basic research and is expected to contribute to elucidating the relationship between CDH13 and diseases, including neurodevelopmental disorders and cancer.