Methods for making a combinatorial antibody library from human germline segments are provided. Also provided are libraries of nucleic acid molecules compiled from germline segments encoding VL chains and libraries of nucleic acid molecules encoding VH chains, and resulting antibody libraries. The libraries are provided as addressable libraries. Methods for screening antibody libraries against a target protein antigen, and the identified or selected antibodies are provided.本明細書では、抗DLL4抗体及びDLL4に関連した疾患又は障害における治療薬として抗DLL4抗体の使用法を提供する。