Peptide compatible to PD-1, and application of peptide compatible to PD-1

The invention specifically relates to a peptide P1 compatible to PD-1, or a modifying peptide of the peptide P1. The amino acid sequence of the peptide P1 is SEQID NO.1, and the modifying peptide is an alanine scanning peptide, a point mutation peptide or a cutting-off peptide of the peptide P1. The configurations of amino acids of the peptide disclosed by the invention are independently selectedfrom a D type or an L type. The peptide disclosed by the invention is compatible to the PD-1, can also block interaction between PD-1/PD-L1, so that the peptide can be used as a precursor peptide fordeveloping a PD-1/PD-L1 inhibitor, and a base is provided for research and development of medicines for resisting tumors or other types of diseases. 本发明具体涉及一种亲和PD-1的肽P1或其修饰肽，肽P1的氨基酸序列为SEQ ID NO.1，修饰肽为其丙氨酸扫描肽、点突变肽或截断肽。本发明肽的各氨基酸的构型独立地选自D型或L型。本发明的肽在亲和PD-1的同时还能够阻断PD-1/PD-L1之间的相互作用，从而可作为开发PD-1/PD-L1抑制剂的先导肽，为抗肿瘤或其它类型疾病的药物研发提供基础。