The B cell hypothesis of rheumatoid arthritis pathogenesis - Part One. This hypothesis proposes that B-cell precursors (A) develop in the bone marrow, (B) exit to the peripheral blood, and (C) reach the subchondral region of the joint via vasculature and lymphatics. A similar process would occur within synovial membrane (not shown). (D) An affected metacarpal (or metatarsal) head is shown with a cortical erosion (arrow) and infiltration of the underlying bone marrow as shown in Figure 3.
McQueen Arthritis Research & Therapy 2012 14:224 doi:10.1186/ar4035