KIF20B and paroxysmal nocturnal hemoglobinuria: Outside of studies of KIF20B molecular partners and ligands, an in-depth study of KIF20B/MPP1 as an autoantibody target in human diseases has not been published, although there is a single report describing KIF20B autoantibodies in paroxysmal nocturnal hemoglobinuria.(14) To facilitate further research of biomarkers in autoimmune diseases, we now report the features of a monoclonal antibody directed against KIF20B.