DSG1 and acquired polycythemia vera: It is now known that pemphigus foliaceus (PF) is characterized by autoantibodies to desmoglein (Dsg) 1 and pemphigus vulgaris (PV) is characterized by autoantibodies to Dsg3, although 60% of PV sera also contain Dsg1 autoantibodies [61,62,63].