The 8D6 protein, also known as 8D6A, CD320 or FDC-SM-8D6, is a single pass, type I membrane protein with two low-density lipoprotein receptornligand binding repeats (LDL-A modules). It is expressed by follicular dendritic cells in the germinal center and acts as a stimulatory signaling molecule. Follicular dendritic cells and T cells interact with germinal center B cells, providing signals for survival, proliferation and differentiation into memory B cells and plasma cells. A disruption of this interaction results in apoptosis of B cells. 8D6 is a growth factor required for plasma cell generation from germinal center B cells. Protein 8D6, together with HCAM (or CD44), plays a significant role in the proliferation of lymphoma cells of germinal center origin. 8D6 is responsible for enhancing proliferation while HCAM inhibits apoptosis.
