Xid and Xid-like immunodeficiencies from a signaling point of view

The analysis of Btk-associated molecules and ligand-induced Btk phosphorylation has suggested the existence of a complexed Btk-associated signaling network involved in the activation of B lymphocytes and mast cells. Recent gene targeting experiments have revealed protein kinase C βI/II (PKCβI/II) as a critical component of the Btk-dependent signaling chain and have highlighted a potential role for the Btk-PKCβI/II interaction in the amplification of B cell receptor mediated signaling.