title: Aberrant proplatelet formation in chronic myeloproliferative neoplasms.
abstract: Proplatelets represent pseudopodia of megakaryocytes which extend into bone marrow sinuses to release platelets. Proplatelets were visualized by immunohistochemical and confocal microscopy. In trephines from essential thrombocythaemia (ET, n=10), fibrotic (n=10) and pre-fibrotic (n=10) primary myelofibrosis (PMF) there was a significant increase of proplatelet density compared with normal bone marrow samples (n=10; p<0.001). Manifest fibrosis exhibited the highest density and volume ratio with significant differences to non-fibrotic PMF (p<0.001) and ET (p<0.001). This study demonstrates that besides megakaryocytic proliferation extensive pseudopodial proplatelet formation provides a hallmark of MPN. Fibrosing differ from non-fibrosing MPN by density and size of aberrant proplatelets.
authors.affiliation: Institute of Pathology, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany.
authors.forename: Michaela
authors.initials: M
authors.lastname: Muth
authors.forename: Guntram
authors.initials: G
authors.lastname: Büsche
authors.forename: Oliver
authors.initials: O
authors.lastname: Bock
authors.forename: Kais
authors.initials: K
authors.lastname: Hussein
authors.forename: Hans
authors.initials: H
authors.lastname: Kreipe
mesh_terms: D001792:Blood Platelets / Q000473:pathology*; D001854:Bone Marrow Cells / Q000473:pathology; D049109:Cell Proliferation; D048430:Cell Shape; D048429:Cell Size; D006801:Humans; D007150:Immunohistochemistry; D008533:Megakaryocytes / Q000473:pathology / Q000648:ultrastructure*; D018613:Microscopy, Confocal; D009196:Myeloproliferative Disorders / Q000473:pathology*; D055728:Primary Myelofibrosis / Q000473:pathology; D011554:Pseudopodia / Q000473:pathology; D013921:Thrombocytopenia / Q000473:pathology