APRIL Protein

Background

TNFSF13, also known as APRIL (A Proliferation-Inducing Ligand), is a protein within the tumor necrosis factor (TNF) superfamily involved in immune system regulation, especially in B-cell survival, proliferation, and antibody production. This ligand, encoded by the TNFSF13 gene, binds to specific receptors on immune cells, including TACI (Transmembrane Activator and Calcium-Modulating Cyclophilin Ligand Interactor) and BCMA (B-Cell Maturation Antigen), to initiate signaling pathways that promote immune responses and sustain humoral immunity. APRIL, along with BAFF (B-cell Activating Factor), another TNF family ligand, is essential for adaptive immunity, supporting B cell maturation and differentiation. APRIL is mainly expressed by myeloid cells, such as dendritic cells and macrophages, and some types of lymphoid cells. Beyond its role in immune cell survival, APRIL has clinical significance, as its overexpression has been associated with autoimmune diseases, certain cancers, and inflammatory disorders. The APRIL/BAFF signaling pathways represent crucial targets for immunotherapy, especially in treating autoimmune diseases and B-cell malignancies.