Abstract: A method for improving the amount of platelets produced. The production method is a method for producing multinucleated megakaryocyte cells with enhanced platelet production capability, the method including a multinucleation step of inducing multinucleated megakaryocyte cells through multinucleation of pre-multinucleated megakaryocyte cells in the presence of a growth factor of the pre-multinucleated megakaryocyte cells. In the multinucleation step, the multinucleated megakaryocyte cells are induced by suppressing the activity of at least one protein selected from the group consisting of an aryl hydrocarbon receptor (AhR), a Rho-associated kinase (ROCK), dual-specificity tyrosine phosphorylation-regulated kinases (DYRK), and myosin 2, and multinucleating the pre-multinucleated megakaryocyte cells in the presence of harmine.

Abstract: Healthy functional platelets are mass produced. A method for producing platelets, comprising: (1) a culture step of culturing megakaryocytes in a platelet producing medium in the presence of mechanical stress and platelet production promoting factors including MIF, NRDc, IGFBP2, TSP-1, PAI-1, and CCL5, and (2) a harvest step of harvesting the platelets obtained by the culture step; wherein the culture step comprises: (a) a step of promoting a release of the platelet production promoting factors from megakaryocytes by mechanical stress; and/or (b) a step of externally adding platelet production promoting factors including MIF, NRDc, and IGFBP2.

Abstract: The present invention provides a method for screening for platelet production promoters, the method including a step for selecting a candidate substance that significantly increases expression of TUBB1 as a platelet production promoter.

Abstract: Healthy functional platelets are mass produced. A method for producing platelets, comprising: (1) a culture step of culturing megakaryocytes in a platelet producing medium in the presence of mechanical stress and platelet production promoting factors including MIF, NRDc, IGFBP2, TSP-1, PAI-1, and CCL5, and (2) a harvest step of harvesting the platelets obtained by the culture step; wherein the culture step comprises: (a) a step of promoting a release of the platelet production promoting factors from megakaryocytes by mechanical stress; and/or (b) a step of externally adding platelet production promoting factors including MIF, NRDc, and IGFBP2.

Abstract: Provided is a method for inducing mesoderm, comprising a step of bringing pluripotent stem cells into contact with bone morphogenetic protein 4 (BMP4) or CHIR for at least 3 days.

Abstract: The present invention provides a method for screening for platelet production promoters, the method including a step for selecting a candidate substance that significantly increases expression of TUBB1 as a platelet production promoter.

Abstract: The present invention provides a method for screening for platelet production promoters, the method including a step for selecting a candidate substance that significantly increases expression of TUBB1 as a platelet production promoter.

Abstract: Methods of production and apparatuses for production for stably producing healthy and functional platelets, and methods for determining operating conditions of an apparatus for producing platelets are provided. The present invention relates to methods of production comprising a step of culturing megakaryocytes in a platelet production medium C, wherein the step of culturing comprises a step of stirring a medium C in containers 1, 4 using stirring mechanisms 2, 5. In one method of production, the step of stirring comprises reciprocating stirring blades 21, 24 in the stirring mechanisms 2, 24 such that any of predetermined turbulent energy, shearing stresses, or Kolmogorov scale is produced, in the medium C. In another method of production, the step of stirring comprises pivoting a stirring blade 51 in the stirring mechanism 5 wherein a plurality of stationary members 53 is placed therearound in a bottom region 4e of the container 4 such that the step of stirring produces turbulence in the medium C.

Abstract: The present invention provides a highly functional platelet production promoting agent which comprises one or a plurality of aryl hydrocarbon receptor (AhR) antagonists and one or a plurality of Rho-associated coiled-coil forming kinase (ROCK) inhibitors.

Abstract: The present invention provides: a platelet production promoter that contains one or more substances selected from the group consisting of Wnt inhibitors and FMS-like tyrosine kinase (FLT) inhibitors; and a platelet production method that uses this platelet production promoter.

Abstract: Healthy functional platelets are mass produced. A method for producing platelets, comprising: (1) a culture step of culturing megakaryocytes in a platelet producing medium in the presence of mechanical stress and platelet production promoting factors including MIF, NRDc, IGFBP2, TSP-1, PAI-1, and CCL5, and (2) a harvest step of harvesting the platelets obtained by the culture step; wherein the culture step comprises: (a) a step of promoting a release of the platelet production promoting factors from megakaryocytes by mechanical stress; and/or (b) a step of externally adding platelet production promoting factors including MIF, NRDc, and IGFBP2.

Abstract: Provided is a method for inducing mesoderm, comprising a step of bringing pluripotent stem cells into contact with bone morphogenetic protein 4 (BMP4) or CHIR for at least 3 days.

Abstract: The present invention provides a highly functional platelet production promoting agent which comprises one or a plurality of aryl hydrocarbon receptor (AhR) antagonists and one or a plurality of Rho-associated coiled-coil forming kinase (ROCK) inhibitors.

Abstract: The present invention provides a method for screening for platelet production promoters, the method including a step for selecting a candidate substance that significantly increases expression of TUBB1 as a platelet production promoter.

Abstract: The present invention provides: a platelet production promoter that contains one or more substances selected from the group consisting of Wnt inhibitors and FMS-like tyrosine kinase (FLT) inhibitors; and a platelet production method that uses this platelet production promoter.