(Press-News.org) Ex vivo expansion of hematopoietic stem cells from cord blood
Compared to hematopoietic stem cells (HSCs) isolated from adults, HSCs isolated from cord blood (CB) have enhanced proliferative potential and can lead to hematological reconstitution when engrafted in children with hematological malignancies or genetic defects. Unfortunately, small numbers of HSCs are present in single CB collections, limiting their use as grafts for adults. For several decades investigators have used a variety of strategies to expand the numbers of CB HSC ex vivo with limited success. Evidence indicates that accumulation of epigenetic modifications influences preservation of stem cell characteristics in HSC daughter cells; therefore, in this issue of the Journal of Clinical Investigation, Pratima Chaurasia and colleagues at Mount Sinai School of Medicine expanded CB HSCs in the presence of histone deacetylase inhibitors (HDACIs) and evaluated their characteristics. Valproic acid (VPA)-treated CB HSCs produced greater numbers of HSCs that expressed several pluripotency genes. Compared to conventionally expanded CB HSCs, VPA-treated HSCs were more efficient in repopulating the bone marrow and establishing hematopoietic populations in immune deficient mice. In an accompanying Commentary, Hal Broxmeyer of the Indiana University School of Medicine discusses how these findings enhance our understanding of HSC function and could provide clinical benefit.
TITLE:
Epigenetic reprogramming induces the expansion of cord blood stem cells
AUTHOR CONTACT:
Ronald Hoffman
Mount Sinai School of Medicine, New York, NY, USA
Phone: 212-241-1948; Fax: 212-876-5276; E-mail: ronald.hoffman@mssm.edu
OR
Pratima Chaurasia
Mount Sinai School of Medicine, New York, NY, USA
Phone: 212.241.1766; Fax: 212.876.5276; E-mail: pratima.chaurasia@mssm.edu
View this article at: http://www.jci.org/articles/view/70313
ACCOMPANYING COMMENTARY
TITLE:
Inhibiting HDAC for human hematopoietic stem cell expansion
AUTHOR CONTACT:
Hal E. Broxmeyer
Indiana University School of Medicine, Indianapolis, IN, USA
Phone: 317-274-7504 (Tel); Fax: 317-274-7592; E-mail: hbroxmey@iupui.edu
View this article at: http://www.jci.org/articles/view/75803
Receptors in the brain mediate the weight loss effects of GLP1 agonists
Glucagon-like peptide-1 (GLP1) analogs are able to achieve both weight loss and glucose tolerance, both of which are crucial for controlling type 2 diabetes (T2D). GLP1 receptors (GLP1Rs) are present in the brain, but it is not clear if the brain does indeed mediate the weight loss and glucose lowering effects of GLP1 analogs. In this issue of the Journal of Clinical Investigation, Stephanie Sisley and colleagues at Cincinnati Children's Hospital Medical Center evaluated the effects of the GLP1 agonist liraglutide in animals lacking GLP1R in the central nervous system (CNS) or in visceral nerves and found that liraglutide had no effect on weight loss or food intake in these animals, even those fed a high fat diet. Interestingly, liragludtie administration did lower glucose levels in animals lacking GLP1R in either the CNS or visceral nerves. Together, these data indicate that neuronal GLP1Rs mediate weight loss and anorectic effects, but do not mediate glucose lowering.
TITLE:
Neuronal GLP1R mediates liraglutide's anorectic but not glucose-lowering effect
AUTHOR CONTACT:
Stephanie Sisley
Baylor College of Medicine, Houston, TX, USA
Phone: 513-465-8701; Fax: 713-798-7057; E-mail: steph.sisley@yahoo.com
View this article at: http://www.jci.org/articles/view/72434
CARDIOLOGY
TITLE:
Epac1–dependent phospholamban phosphorylation mediates the cardiac response to stresses
AUTHOR CONTACT:
Satoshi Okumura
Tsurumi University, Yokohama, UNK, JPN
Phone: 011-81-45-580-8476; Fax: 011-81-45-585-2889; E-mail: okumura-s@tsurumi-u.ac.jp
View this article at: http://www.jci.org/articles/view/64784
ONCOLOGY
TITLE:
Mesenchymal gene program-expressing ovarian cancer spheroids exhibit enhanced mesothelial clearance
AUTHOR CONTACT:
Joan Brugge
Harvard Medical School, Boston, MA, USA
Phone: 617/432-3974; Fax: 617-432-3969; E-mail: Joan_Brugge@hms.harvard.edu
View this article at: http://www.jci.org/articles/view/69815
TITLE:
The tumor suppressor folliculin regulates AMPK-dependent metabolic transformation
AUTHOR CONTACT:
Arnim Pause
McGill University, Montreal, PQ, CAN
Phone: 514-398-1521; E-mail: arnim.pause@mcgill.ca
View this article at: http://www.jci.org/articles/view/71749
TITLE:
ZEB1 sensitizes lung adenocarcinoma to metastasis suppression by PI3K antagonism
AUTHOR CONTACT:
Jonathan Kurie
University of Texas MD Anderson Cancer Center, Houston, TX, USA
Phone: 713-745-6747; Fax: 713-792-1220; E-mail: jkurie@mdanderson.org
OR
Yanan Yang
Mayo Clinic, Rochester, MN, USA
Phone: 507.284.8754; Fax: 507.284.9207; E-mail: yang.yanan@mayo.edu.
View this article at: http://www.jci.org/articles/view/72171
IMMUNOLOGY
TITLE:
Intrinsic TGF-β signaling promotes age-dependent CD8+ T cell polyfunctionality attrition
AUTHOR CONTACT:
Imitaz Khan
George Washington University, Washington, DC, USA
Phone: 202.994.2863; Fax: 202.994.2913; E-mail: imti56@gwu.edu
View this article at: http://www.jci.org/articles/view/70522
NEUROSCIENCE
TITLE:
Peripheral nervous system plasmalogens regulate Schwann cell differentiation and myelination
AUTHOR CONTACT:
Pedro Brites
Instituto de Biologia Molecular e Celular, Porto, , PRT
Phone: 00351226074900; Fax: ; E-mail: pedro.brites@ibmc.up.pt
View this article at: http://www.jci.org/articles/view/72063
ENDOCRINOLOGY
TITLE:
Estrogen promotes Leydig cell engulfment by macrophages in male infertility
AUTHOR CONTACT:
Xiangdong Li
State Key Laboratory of Agro-Biotechnology, Beijing, CHN
Phone: 86-1062734389; E-mail: xiangdongli@cau.edu.cn
View this article at: http://www.jci.org/articles/view/59901
INFORMATION:
JCI online ahead of print table of contents for April 24, 2014
2014-04-24
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