XIAP and Immunodeficiency: Targeting the E3 ubiquitin ligase x-linked inhibitor of apoptosis (<i>xiap</i>) and its substrate <i>p47</i> led to an alteration in molecular signaling within the immune deficiency network and increased infection of the rickettsial agent <i>Anaplasma phagocytophilum</i> in <i>I.