Provided are anti-PD-1 antibodies or fragments thereof. In various example, the antibodies or fragments thereof includes a heavy chain variable region comprising heavy chain complementarity determining regions HCDR1, HCDR2, and HCDR3, and a light chain variable region comprising light chain complementarity determining regions LCDR1, LCDR2, and LCDR3, wherein the HCDR1, HCDR2, HCDR3, LCDR1, LCDR2, and LCDR3 are selected from the group consisting of (a) HCDR1: GFTFSSYT (SEQ ID NO: 1), HCDR2: ISHGGGDT (SEQ ID NO: 2), HCDR3: ARHSGYERGYYYVMDY (SEQ ID NO: 3), LCDR1: ESVDYYGFSF (SEQ ID NO: 4), LCDR2: AAS (SEQ ID NO: 5), LCDR3: QQSKEVPW (SEQ ID NO: 6)； (b) HCDR1: GYTFTSYT (SEQ ID NO: 7), HCDR2: INPTTGYT (SEQ ID NO: 8), HCDR3: ARDDAYYSGY (SEQ ID NO: 9), LCDR1: ENIYSNL (SEQ ID NO: 10), LCDR2: AAK (SEQ ID NO: 11), LCDR3: QHFWGTPWT (SEQ ID NO: 12)； and (c) HCDR1: GFAFSSYD (SEQ ID NO: 13), HCDR2: ITIGGGTT (SEQ ID NO: 14), HCDR3: ARHRYDYFAMDN (SEQ ID NO: 15), LCDR1: ENVDNYGINF (SEQ ID NO: 16), LCDR2: VSS (SEQ ID NO: 17), LCDR3: QQSKDVPW (SEQ ID NO: 18). Methods of using the antibodies or fragments thereof for treating and diagnosing diseases such as cancer, infection or immune disorders are also provided.本發明提供抗PD-1抗體或其片段。在各種實例中，所述抗體或其片段包含重鏈可變區和輕鏈可變區，所述重鏈可變區包含重鏈互補決定區HCDR1、HCDR2和HCDR3，所述輕鏈可變區包含輕鏈互補決定區LCDR1、LCDR2和LCDR3，其中所述HCDR1、HCDR2、HCDR3、LCDR1、LCDR2、和LCDR3選自下列所組成之群：(a) HCDR1: GFTFSSYT (SEQ ID NO: 1)、HCDR2: ISHGGGDT (SEQ ID NO: 2)、HCDR3: ARHSGYERGYYYVMDY (SEQ ID NO: 3)、LCDR1: ESVDYYGFSF (SEQ ID NO: 4)、LCDR2: AAS (SEQ ID NO: 5)、LCDR3: QQSKEVPW (SEQ ID NO: 6)；(b) HCDR1: GYTFTSYT (SEQ ID NO: 7)、HCDR2: INPTTGYT (SEQ ID NO: 8)、HCDR3: ARDDAYYSGY (SEQ ID NO: 9)、LCDR1: ENIYSNL (SEQ ID NO: 10)、LCDR2: AAK (SEQ ID NO: 11)、LCDR3: QHFWGTPWT (SEQ ID NO: 12)；和(c) HCDR1: GFAFSSYD (SEQ ID NO: 13)、HCDR2: ITIGGGTT (SEQ ID NO: 14)、HCDR3: ARHRYDYFAMDN (SEQ ID NO: 15)、LCDR1: ENVDNYGINF (SEQ ID NO: 16)、LCDR2: VSS (SEQ ID NO: 17)、LCDR3: QQSKDVPW (SEQ ID NO: 18)。本發明還提供了使用所述抗體或其片段來治療和診斷諸如癌症、感染或免疫疾病等疾病的方法。
