DSG1 and acquired polycythemia vera: Sera of PV patients, including those with acute PV having negative detection of anti-DSG1/3 autoantibodies, also contain antibodies against the classical E-cadherin [94] as well as several other adhesion molecules such as DSG4 [95,96], desmoplakin [97], desmocollins [90], PERP [90], and pemphaxin [98].