CD20 is a leukocyte surface antigen consisting of four transmembrane regions and cytoplasmic N- and C-termini. It is suspected that it acts as a calcium channel in the cell membrane.It has been shown that CD20 plays a role in the microenvironmental interactions of B cells. CD20 is expressed on all stages of B cell development except the first and last; it is present from late pro-B cells through memory cells, but not on either early pro-B cells or plasma blasts and plasma cells. The expression of CD20 is regulated by the chemokine signalling through the CXCR4/SDF1 axis, and this can be impaired by drugs interfering with microenvironmental interactions.
