Embryonic stem cells (ESC) have been established previously from the inner cell mass cells of mouse blastocysts. In suspension culture, they spontaneously differentiate to blood-island-containing cystic embryoid bodies (CEB). The development of blood vessels from in situ differentiating endothelial cells of blood islands, a process which we call vasculogenesis, was induced by injecting ESC into...

Cancer is, by definition, the uncontrolled growth of autonomous cells that eventually destroy adjacent tissues and generate architectural disorder. However, this concept cannot be totally true. In three well documented studies, we have demonstrated that cancer tissues produce order zones that evolve over time and generate embryoid body structures in a space-time interval. The authors decided to...

To establish a murine model that may allow for definition of the precise role of phospholamban in myocardial contractility through selective perturbations in the phospholamban gene, we initiated studies on the role of phospholamban in the murine heart. Intact beating hearts were perfused in the absence or presence of isoproterenol, and quantitative measurements of cardiac performance were obtai...

Paroxysmal nocturnal hemoglobinuria (PNH) develops in patients who have had a somatic mutation in the X-linked PIG-A gene in a hematopoietic stem cell; as a result, a proportion of blood cells are deficient in all glycosyl phosphatidylinositol (GPI)-anchored proteins. Although the PIG-A mutation explains the phenotype of PNH cells, the mechanism enabling the PNH stem cell to expand is not clear...

Blood islands, the precursors of yolk sac blood vessels, contain primitive erythrocytes surrounded by a layer of endothelial cells. These structures differentiate from extra-embryonic mesodermal cells that underlie the visceral endoderm. Our previous studies have shown that Indian hedgehog (Ihh) is expressed in the visceral endoderm both in the visceral yolk sac in vivo and in embryonic stem (E...

Teratomas are benign tumors that form after ectopic injection of embryonic stem (ES) cells into mice and contain derivatives of all primitive germ layers. To study the role of beta 1 integrin during teratoma formation, we compared teratomas induced by normal and beta1-null ES cells. Injection of normal ES cells gave rise to large teratomas. In contrast, beta 1-null ES cells either did not grow ...

Human embryonic stem (ES) cells are undifferentiated pluripotent cells derived from the inner cell mass of blastocyst stage embryos. These unique cell lines have the potential to form virtually any cell type in the body and can be propagated in vitro indefinitely in an undifferentiated state. These cells are capable of forming embryoid bodies (EB) that contain cells from all three embryonic lin...

Embryoid body (EB) formation closely recapitulates early embryonic development with respect to lineage commitment. Because it is greatly affected by cell-cell and cell-substrate interactions, the ability to control the initial number of cells in the aggregates and to provide an appropriate substrate are crucial parameters for uniform EB formation. Here we report of an ultra-rapid fabrication an...

Embryonic stem cells (ESCs) are an established model for investigating developmental processes, disease conditions, tissue regeneration and therapeutic targets. Previous studies have shown that tripartite motif-containing 33 protein (Trim33) functions as a chromatin reader during Nodal-induced mesoderm induction. Here we report that despite reduced proliferation, mouse ESCs deficient in Trim33 ...