BAFF, also known as BLyS, TALL-1, THANK, and TNFSF13B, is a 32 kDa transmembrane glycoprotein belonging to the TNF ligand superfamily. It plays a crucial role in the survival, proliferation, and differentiation of B cells. Mouse BAFF shares 72% amino acid sequence identity with human BAFF within its extracellular domain. This cytokine is produced by various hematopoietic cells, including monocytes, macrophages, neutrophils, dendritic cells, T cells, and adipocytes. BAFF binds to three receptors primarily expressed by B cells: BAFF-R, TACI, and BCMA. Elevated BAFF levels are associated with autoimmune diseases and B cell malignancies.
BAFF has gained attention in the field of organoid culture due to its critical role in B cell biology and its potential to influence the immune microenvironment within organoids. For example, in organoids derived from lymphoid tissues, BAFF can help maintain B cell viability and support the formation of germinal centers.