CD27

Class

Agonist anti-CD27 monoclonal antibody (humanized, MK-5890)

Pathway

TNFRSF costimulatory activation of T cells, enhancing T-cell-mediated antitumor responses

CD27 is a costimulatory receptor belonging to the tumor necrosis factor receptor superfamily (TNFRSF), expressed on T cells, natural killer (NK) cells, and some B cells. Its natural ligand, CD70, is displayed transiently on activated antigen-presenting cells during an immune response. When CD27 engages CD70, it delivers a second, supportive signal that works alongside the primary T-cell receptor signal, helping activated T cells survive, proliferate, and mature into effector and memory cells capable of sustained antitumor activity. In cancers, tumors often create an environment where this costimulatory signal is weak or absent, leaving T cells under-activated or prone to becoming dysfunctional. Agonist antibodies directed against CD27 are designed to substitute for or amplify the natural CD70 signal, driving stronger, more durable T-cell responses against tumor antigens. Because this pathway also supports NK-cell and B-cell function, CD27 agonism is of interest across a range of solid and hematologic malignancies, frequently in combination with other immune-modulating therapies such as checkpoint inhibitors, which relieve inhibitory signals rather than provide costimulation.