The present invention is directed to selected anti-PD-1 antibodies capable of binding to both cynomolgus monkey PD-1 and to human PD-1: PD-1 mAb 1, PD-1 mAb 2, PD-1 mAb 3, PD-1 mAb 4, PD-1 mAb 5, PD-1 mAb 6, PD-1 mAb 7, PD-1 mAb 8, PD-1 mAb 9, PD-1 mAb 10, PD-1 mAb 11, PD-1 mAb 12, PD-1 mAb 13, PD-1 mAb 14, or PD-1 mAb 15, and to humanized and chimeric versions of such antibodies. The invention additionally pertains to PD-1-binding molecules that comprise PD-1 binding fragments of such anti-PD-1 antibodies, immunocongugates, and to bispecific molecules, including diabodies, BiTEs, bispecific antibodies, etc., that comprise (i) such PD-1-binding fragments, and (ii) a domain capable of binding an epitope of a molecule involved in regulating an immune check point present on the surface of an immune cells. The present invention also pertains to methods of using molecules that bind PD-1 for stimulating immune responses, as well as methods of detecting PD-1.本發明涉及選擇的能夠結合食蟹猴PD-1和人PD-1的抗PD-1抗體：PD-1 mAb 1、PD-1 mAb 2、PD-1 mAb 3、PD-1 mAb 4、PD-1 mAb 5、PD-1 mAb 6、PD-1 mAb 7、PD-1 mAb 8、PD-1 mAb 9、PD-1 mAb 10、PD-1 mAb 11、PD-1 mAb 12、PD-1 mAb 13、PD-1 mAb 14或PD-1 mAb 15，和這類抗體的人源化和嵌合形式。本發明另外涉及PD-1結合分子，其包括這類抗PD-1抗體的PD-1結合片段、免疫綴合物，和雙特異性分子，包括雙抗體、BiTE、雙特異性抗體等，其包括(i)這樣的PD-1結合片段，和(ii)能夠結合參與調節免疫檢查點的免疫細胞的表面上存在的分子的表位元的結構域。本發明也涉及使用PD-1結合分子刺激免疫應答的方法，以及檢測PD-1的方法。
