P4HB and autoimmune polyendocrinopathy: Proteomic studies have demonstrated that aPLs are also responsible for the altered protein profile of APS monocytes, involving deregulated expression of annexin A1 (AnxA1), annexin A2 (AnxA2), ubiquitin-like protein Nedd8, Rho A protein, protein disulfide isomerase (PDI), and Heat shock protein-60 (Hsp60).