Provided herein are antibodies, or antigen binding portions thereof, that bind to OX40. Also provided are uses of these proteins in therapeutic applications, such as in the treatment of cancer. Further provided are cells that produce the antibodies, polynucleotides encoding the heavy and/or light chain variable region of the antibodies, and vectors comprising the polynucleotides encoding the heavy and/or light chain variable region of the antibodies.本文提供結合至OX40之抗體或其抗原結合部分。亦提供該等蛋白質於治療應用,如:於癌症之治療中之用途。進一步提供產生該等抗體之細胞、編碼該等抗體之重鏈及/或輕鏈可變區之聚核苷酸及包含編碼該等抗體之重鏈及/或輕鏈可變區之該等聚核苷酸的載體。