Platelet production of megakaryocyte: A review with original observations on humanin vivocells 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.

Megakaryocytes in Bone Metastasis: Protection or Progression?

“…MKs can also be multinucleated with pyknotic nuclei and prominent granular cytoplasm (Figure 1). In the last stage, terminally differentiated MKs extrude long cytoplasmic processes into the sinusoid lumen through gaps in the endothelium, and release pro-platelets into the blood stream [19]. Mature MKs are, in fact, present in a specialized area of the bone marrow in close proximity to the vascular sinusoid, where they are subjected to changes that lead to the release of platelets.…”

Quantitative systems pharmacology model of thrombopoiesis and platelet life‐cycle, and its application to thrombocytopenia based on chronic liver disease

“…Approximately 1-4 × 10 11 platelets are produced daily by megakaryocytes. [2][3][4] One megakaryocyte produces around 1000-10,000 platelets. [2][3][4] The average life-span of platelets is 8 to 10 days.…”

“…[2][3][4] One megakaryocyte produces around 1000-10,000 platelets. [2][3][4] The average life-span of platelets is 8 to 10 days. 5 In a healthy state, about one-third of the platelets is pooled in the spleen and two-thirds are distributed throughout the rest of the vascular system.…”

The RNA-Binding Protein ATXN2 is Expressed during Megakaryopoiesis and May Control Timing of Gene Expression

“…Megakaryopoiesis encompasses the commitment of hematopoietic stem cells (HSCs) towards megakaryoblasts (MKBLs) that proliferate and subsequently differentiate to large polyploid megakaryocytes (MKs), ultimately releasing platelets (PLTs) into the blood stream [1,2]. Megakaryopoiesis entails several unique features, including endomitosis [3].…”