Novel Culture Medium using a Small-molecule Agonist of Thrombopoetin Receptor
Poster Mar 20, 2015
Hondo M1; Nishino T2; Inamura M1
Hematopoietic stem cells (HSCs), defined by their capacity to self-renew and differentiate into all blood cell lineages, can be applied for transplantation therapy. Since a large number of HSCs are required for clinical use, improvement of techniques for expansion of HSCs ex vivo is a critical issue. Several cytokines have been used for this purpose. Thrombopoietin (TPO) is an essential cytokine that regulates megakaryocyte production and HSC proliferation via activating signaling through its receptor c- MPL. We have developed a small-molecule agonist (NR-101) of c-MPL and report that human HSCs are expanded efficiently ex vivo with NR-101. Using a new small-molecule agonist NR- 102 which is related to NR-101, we produced a novel culture medium, ReproHSCTM. The cost for culture of human HSC can be reduced by using this small-molecule.
Here we demonstrated that ReproHSCTM efficiently expands human CD34+CD38- primitive hematopoietic cells in culture and thereby enhances repopulating capacity of HSCs in NOD/SCID mice. Human blood cord CD34+ cells were cultured with ReproHSCTM supplemented with only Stem Cell Factor (SCF) for 7 days. The total cell number was increased about 40-fold during culture. CD34+ cells and CD34+CD38- cells were expanded 12- fold and 8.5-fold, respectively. We then transplanted expanded cells with ReproHSCTM supplemented with SCF and flt3 ligand for 14 days into NOD/SCID mice and analyzed the SCID-repopulating CD45+ cells with flow cytometry. The expanded cells established engraftment better than the fresh CD34+ cells did. These results indicate that ReproHSCTM is a novel medium suitable for the expansion of HSCs ex vivo.
The nuclear receptors pregnane X receptor (PXR) and constitutive androstane receptor (CAR) are closely related transcription factors that regulate the expression of phase I (cytochrome P450s), phase II metabolizing enzymes and transporter genes in response to xenobiotics, including prescription drugs.READ MORE
We found a distinct subpopulation of Tregs within BMSCs. Tregs and BMSCs in co-culture conferred neuroprotection that varied in a dose-dependent manner. Tregs minimized stem cell production of IL-6, a pro-inflammatory cytokine, and inhibited BMSC secretion of FGF-beta, a cytokine related to BMSC proliferation and differentiation. The ratio of Tregs found natively in BMSCs is optimally adapted to provide the maximum neuroprotective benefit of stem cell treatment after ischemic stroke.READ MORE
3rd International Conference On Agricultural Engineering and Food Security
Nov 12 - Nov 13, 2018
25th International Conference on Advanced Clinical Research and Clinical Trials
Sep 16 - Sep 17, 2019
8th InterAmerican Oncology Conference 'Current Status and Future of Anti-Cancer Therapies'
Oct 17 - Oct 18, 2019