title: Platelet production of megakaryocyte: A review with original observations on human in vivo cells and bone marrow.
abstract: Megakaryocytes (MKs) build characteristic structures to produce platelets in a series of steps. Although mechanisms of demarcation membrane system (DMS) and open canalicular system transformation have been proposed based on experimental studies in recent decades, the related evidence is lacking in human cells in vivo. The present review describes and discusses the development of MKs, transformation of DMS, and the release and maturation of proplatelets based on our observation of human MKs in vivo and bone marrow biopsy by light microscope and transmission electron microscope. Four stages were subdivided from megakaryoblasts to matured cells; presumption of DMS transformation from endoplasmic reticulum and Golgi apparatus were evidenced in contrast to another presumption of DMS transformation from plasma membrane in this review. Effectors of interaction between hematopoietic cells, the sucking and shearing force of sinus blood flow on movement of MKs, and release of proplatelets were emphasized. Additionally, the mechanism of secondary splitting of proplatelets in circulation was demonstrated ultrastructurally. These findings and conceptions might significantly promote our understanding of the mechanism of platelet production in human in vivo cells.
authors.affiliation: a Institute of Hematology & Blood Diseases Hospital, State Key Laboratory of Experimental Hematology, Peking Union Medical College , Tianjin , China.
authors.forename: Yong-Xin
authors.initials: YX
authors.lastname: Ru
authors.affiliation: a Institute of Hematology & Blood Diseases Hospital, State Key Laboratory of Experimental Hematology, Peking Union Medical College , Tianjin , China.
authors.forename: Shu-Xu
authors.initials: SX
authors.lastname: Dong
authors.affiliation: a Institute of Hematology & Blood Diseases Hospital, State Key Laboratory of Experimental Hematology, Peking Union Medical College , Tianjin , China.
authors.forename: Hao-Yue
authors.initials: HY
authors.lastname: Liang
authors.affiliation: a Institute of Hematology & Blood Diseases Hospital, State Key Laboratory of Experimental Hematology, Peking Union Medical College , Tianjin , China.
authors.forename: Shi-Xuan
authors.initials: SX
authors.lastname: Zhao
mesh_terms: D001792:Blood Platelets / Q000166:cytology* / Q000648:ultrastructure; D001853:Bone Marrow; D002454:Cell Differentiation; D004721:Endoplasmic Reticulum / Q000378:metabolism; D006801:Humans; D008533:Megakaryocytes / Q000166:cytology* / Q000648:ultrastructure
keywords: Demarcation membrane system; endoplasmic reticulum; megakaryocyte; platelet releasing; transformation