In contrast to the study of Ivars at al. (30), we conclude that ADAM10 inhibition is not protective against PV-IgGs with a high level of Dsg1 autoantibodies and therefore the inhibition of ADAMs may be not sufficient for the treatment of all PV patients but may be a promising approach for treatment of mucosal PV. Here, DSG1 is linked to acquired polycythemia vera.