Antibodies and agglomerations of antigens are provided. These antibodies and agglomerations are combined with PD-1 by immunization, preferably with human PD-1 or mouse, to initiate or promote immune response, thus triggering the spread or activity of immune cells. Different from the existing model of PD-1 completely promoting immunosuppressive response, The fragments of the antibody and antigen binding bind with PD-1 in immunity, causing a trigger signal to the immune cells, activating the immune cells, rather than inhibiting the immune cells. To a certain extentThe antibody and the antigen binding fragments of these antibodies are specifically combined with PD-1 expressed in immune cells. In immune cells, the binding of these antibodies and the binding fragments of these antibodies to the antigens of PD-1 can cause activation signals to be sent to immune cells, for example, A signal that improves or promotes cell formation and / or initiates immune cell proliferation. Immune cells that represent PD-1 include B and T-lymphocytes and cells produced from the gallbladder, but do not include steroids. In one model, the immune cells are T-lymphocytes,It's better to have t-cd8 + lymphocytesRESUMEN Se proporcionan anticuerpos y fragmentos de unión al antígeno de estos que se unen inmunoespecíficamente a PD-1, preferentemente, a PD-1 humana o de ratón, e inducen o promueven una respuesta inmunitaria que activa la proliferación o actividad de las células inmunitarias. A diferencia del paradigma existente de que PD-1 promueve exclusivamente una respuesta inmunitaria supresora, los anticuerpos descritos y fragmentos de unión al antígeno de estos se unen inmunoespecíficamente a PD-1 y provocan que se transmita una señal de activación a la célula inmunitaria que activa la célula inmunitaria en lugar de suprimir la célula inmunitaria. En una modalidad, los anticuerpos descritos y los fragmentos de unión al antígeno de estos se unen específicamente a PD-1 expresada en células inmu
