Figure 3

BAFF forms part of an amplification loop that is activated by inflammation. Immune complexes induce interferon-α (IFN-α) secretion from plasmacytoid dendritic cells (DCs) that in turn stimulates myeloid dendritic cells to further activate T and B cells. Activated B cells act as effectors that secrete cytokines and chemokines, present antigen to T cells and migrate to inflamed tissues. Antagonism of T cell activation by dendritic cells or of B cell activation by T cells might synergize with BAFF blockade. APRIL, a proliferation-inducing ligand.