Recombinant Human 4-1BB Ligand Protein

4-1BB ligand (4-1BBL), also known as CD137L or TNFSF9, is a member of the tumor necrosis factor (TNF) family expressed on activated antigen-presenting cells. Its receptor, 4-1BB, is a member of the TNF receptor family expressed on activated CD4 and CD8 T cells. In response to 4-1BB Ligand binding, 4-1BB transduces a co-stimulatory signal that promotes the proliferation, activation, and survival of CD4⁺and CD8⁺T cells. T cell co-stimulation through CD28 is important for the initial T cell expansion, while 4-1BB acts later in the response. Furthermore, 4-1BBL may play a role in cognate interactions between T-cells and B-cells/macrophages. As for diseases, 4-1BBL is involved in cancers, infectious diseases and autoimmune diseases.