APRIL (human) ELISA Kit

The B cell-stimulating molecules, BAFF (B cell activating factor) and APRIL (a proliferation-inducing ligand), are critical factors in the maintenance of the B cell pool and humoral immunity. APRIL binds to transmembrane activator and CAML interactor (TACI), B cell maturation antigen (BCMA), and heparan sulfate proteoglycans (HSPG) within the extracellular matrix or on the surface of cells such as plasma cells. APRIL maintains B cell homeostasis by acting at a later stage, modulating the function and survival of antigen-experienced B cells. APRIL (as well as BAFF) stimulates class-switch recombination (CSR), hence contributes to shaping humoral effector mechanisms. With regards to humoral memory, APRIL is involved in the establishment and survival of the long-lived plasma cell (LLPC) pool in the bone marrow (BM). APRIL is expressed by a number of myeloid-derived cell types including BM granulocytes, megakaryocytes, eosinophils and osteoclasts and by dendritic cells following exposure to IFNα, IFNγ or CD40L. APRIL expression is induced during hematopoiesis in the bone marrow. APRIL expression is not limited to cells of myeloid origin, but can also be found in epithelial cells of the gut, tonsil, breast and skin. Finally, APRIL is expressed in tumor cell lines and human cancer cells of colon, thyroid and lymphoid origin. The B cell-stimulating molecules, BAFF (B cell activating factor) and APRIL (a proliferation-inducing ligand), are implicated in several human autoimmune diseases with autoreactive B cell involvement, including systemic lupus erythematosus (SLE), Sjögren’s syndrome (SS), IgA nephropathy (IgAN) and rheumatoid arthritis (RA). APRIL might also function in enhancing proliferation of some tumor cells, especially B-cell malignancies. BAFF and APRIL contribute to maintaining IgG, IgA, and IgM plasma cells in the bone marrow (BM), spleen and intestine and rely mainly on three ligand/receptor pairs: APRIL-BCMA, BAFF-TACI, and APRIL-TACI. APRIL plays an important role in B cell survival and proliferation, so blocking it can modulate immune responses. APRIL blocking antibodies can be useful for vaccine research, particularly to assess how APRIL inhibition affects normal immune responses to vaccination. The APRIL (human) ELISA Kit is to be used for the in vitro quantitative determination of mouse APRIL in cell culture supernatants, serum and plasma.