title: Thrombopoietin induces production of nucleated thrombocytes from liver cells in Xenopus laevis.
abstract: The development of mammalian megakaryocytes (MKs) and platelets, which are thought to be absent in non-mammals, is primarily regulated by the thrombopoietin (TPO)/Mpl system. Although non-mammals possess nucleated thrombocytes instead of platelets, the features of nucleated thrombocyte progenitors remain to be clarified. Here, we provide the general features of TPO using Xenopus laevis TPO (xlTPO). Hepatic and splenic cells were cultured in liquid suspension with recombinant xlTPO. These cells differentiated into large, round, polyploid CD41-expressing cells and were classified as X. laevis MKs, comparable to mammalian MKs. The subsequent culture of MKs after removal of xlTPO produced mature, spindle-shaped thrombocytes that were activated by thrombin, thereby altering their morphology. XlTPO induced MKs in cultured hepatic cells for at least three weeks; however, this was not observed in splenic cells; this result demonstrates the origin of early haematopoietic progenitors in the liver rather than the spleen. Additionally, xlTPO enhanced viability of peripheral thrombocytes, indicating the xlTPO-Mpl pathway stimulates anti-apoptotic in peripheral thrombocytes. The development of thrombocytes from MKs via the TPO-Mpl system in X. laevis plays a crucial role in their development from MKs, comparable to mammalian thrombopoiesis. Thus, our results offer insight into the cellular evolution of platelets/MKs in vertebrates. (200/200).
authors.affiliation: Department of Biology, Faculty of Education and Integrated Arts and Sciences, Waseda University, 2-2 Wakamatsu, Shinjuku, Tokyo, 162-8480, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Tanizaki
authors.affiliation: Integrative Bioscience and Biomedical Engineering, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu, Shinjuku, Tokyo 162-8480, Japan.
authors.forename: Megumi
authors.initials: M
authors.lastname: Ichisugi
authors.affiliation: Integrative Bioscience and Biomedical Engineering, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu, Shinjuku, Tokyo 162-8480, Japan.
authors.forename: Miyako
authors.initials: M
authors.lastname: Obuchi-Shimoji
authors.affiliation: Integrative Bioscience and Biomedical Engineering, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu, Shinjuku, Tokyo 162-8480, Japan.
authors.forename: Takako
authors.initials: T
authors.lastname: Ishida-Iwata
authors.affiliation: Integrative Bioscience and Biomedical Engineering, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu, Shinjuku, Tokyo 162-8480, Japan.
authors.forename: Ayaka
authors.initials: A
authors.lastname: Tahara-Mogi
authors.affiliation: Integrative Bioscience and Biomedical Engineering, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu, Shinjuku, Tokyo 162-8480, Japan.
authors.forename: Mizue
authors.initials: M
authors.lastname: Meguro-Ishikawa
authors.affiliation: Department of Biology, Faculty of Education and Integrated Arts and Sciences, Waseda University, 2-2 Wakamatsu, Shinjuku, Tokyo, 162-8480, Japan.|Integrative Bioscience and Biomedical Engineering, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu, Shinjuku, Tokyo 162-8480, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kato
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000166:cytology / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics*; D002467:Cell Nucleus / Q000378:metabolism; D022781:Hepatocytes / Q000378:metabolism; D008099:Liver / Q000166:cytology / Q000378:metabolism*; D008533:Megakaryocytes / Q000378:metabolism; D013154:Spleen / Q000378:metabolism; D013917:Thrombin / Q000235:genetics / Q000378:metabolism*; D013926:Thrombopoietin / Q000235:genetics* / Q000378:metabolism; D014982:Xenopus laevis / Q000235:genetics / Q000254:growth & development
chemical_list: D013926:Thrombopoietin; D013917:Thrombin