Publications by authors named "LeeLee Ong"

The possible different therapeutic efficacy of human mesenchymal stem cells (hMSC) derived from umbilical cord blood (CB), adipose tissue (AT) or bone marrow (BM) for the treatment of myocardial infarction (MI) remains unexplored. This study was to assess the regenerative potential of hMSC from different origins and to evaluate the role of CD105 in cardiac regeneration. Male SCID mice underwent LAD-ligation and received the respective cell type (400.

View Article and Find Full Text PDF
Article Synopsis
  • CD133+ cells, which are hemangioblasts, can differentiate into hematopoietic and endothelial cells, with hypoxia/normoxia affecting their balance between stemness and differentiation.
  • In experiments, preconditioning these cells in hypoxic/normoxic conditions showed a noticeable increase in endothelial cell formation but not in other hematopoietic types.
  • Gene expression analysis revealed significant upregulation of angiogenic-related genes under hypoxia, indicating that such preconditioning could enhance the differentiation of CD133+ cells into endothelial cells, potentially benefiting clinical applications.
View Article and Find Full Text PDF

This article is being retracted because another article was published using the same data, but under a different title, in Microvascular Research.

View Article and Find Full Text PDF

Erythropoietin (EPO) protects the myocardium from ischaemic injury and promotes beneficial remodelling. We assessed the therapeutic efficacy of intracardiac EPO injection and EPO-mediated stem cell homing in a rat myocardial infarction (MI) model. Following MI, EPO (3000 U/kg) or saline was delivered by intracardiac injection.

View Article and Find Full Text PDF

Stromal cell-derived factor-1alpha (SDF-1alpha) mediated mobilization and homing of stem cells showed promising potential in stem cell based tissue engineering and regenerative medicine. However local and sustained release of SDF-1alpha is indispensable for stem cell mediated regenerative process due to its short half-life under inflammatory conditions. In this study, a gene activated collagen substrate (GAC) was formed via assembly of plasmid encoding SDF-1alpha into a collagen substrate to create a microenvironment favoring stem cell homing.

View Article and Find Full Text PDF

We investigated the kinetics of human mesenchymal stem cells (MSCs) after intravascular administration into SCID mouse cremaster vasculature by intravital microscopy. MSCs were injected into abdominal aorta through left femoral artery at two different concentrations (1 x 10(6) or 0.2 x 10(6) cell).

View Article and Find Full Text PDF

Background: Systemic gene delivery is limited by the adverse hydrodynamic conditions on the collection of gene carrier particles to the specific area. In the present study, a magnetic field was employed to guide magnetic nanobead (MNB)/polymer/DNA complexes after systemic administration to the left side of the mouse thorax in order to induce localized gene expression.

Methods: Nonviral polymer (poly ethyleneimine, PEI) vector-gene complexes were conjugated to MNBs with the Sulfo-NHS-LC-Biotin linker.

View Article and Find Full Text PDF

In the era of intravascular approaches for regenerative cell therapy, the underlying mechanisms of stem cell migration to non-marrow tissue have not been clarified. We hypothesized that next to a local inflammatory response implying adhesion molecule expression, endothelial nitric oxide synthase (eNOS)-dependent signaling is required for stromal- cell-derived factor-1 alpha (SDF-1alpha)-induced adhesion of c-kit+ cells to the vascular endothelium. SDF-1alpha/tumor necrosis factor-alpha (TNF-alpha)-induced c-kit+-cell shape change and migration capacity was studied in vitro using immunohistochemistry and Boyden chamber assays.

View Article and Find Full Text PDF

Engraftment of mesenchymal stem cells (MSCs) derived from adult bone marrow has been proposed as a potential therapeutic approach for postinfarction left ventricular dysfunction. However, limited cell viability after transplantation into the myocardium has restricted its regenerative capacity. In this study, we genetically modified MSCs with an antiapoptotic Bcl-2 gene and evaluated cell survival, engraftment, revascularization, and functional improvement in a rat left anterior descending ligation model via intracardiac injection.

View Article and Find Full Text PDF

Kinectin is an integral membrane protein with many isoforms primarily found on the endoplasmic reticulum. It has been found to bind kinesin, Rho GTPase, and translation elongation factor-1delta. None of the existing models for the quaternary organization of the elongation factor-1 complex in higher eukaryotes involves kinectin.

View Article and Find Full Text PDF

Objective: The regenerative potential of endothelial and hematopoietic progenitor cells in the heart may vary according to their origin. This study was designed to compare the functional effects of CD133+ cells from human cord blood and bone marrow in a mouse model of myocardial injury.

Methods: 5 x 10(5) CD133+ cells from bone marrow (BM(CD133)) or cord blood (UCB(CD133)) were injected in the necrosis border zone of NOD/SCID (non-obese diabetic/severe combined immunodeficiency) mice with left ventricular cryoinjury (CI+).

View Article and Find Full Text PDF

Kinectin is an integral transmembrane protein on the endoplasmic reticulum, binding to kinesin, interacting with Rho GTPase and anchoring the translation elongation factor-1 complex. There has been debate on the specific role(s) of kinectin in different species and cell types. Here we identified 15 novel kinectin isoforms in the mouse nervous system, constituting a family of alternatively spliced carboxyl-terminal variants.

View Article and Find Full Text PDF

Kinectin has been proposed to be a membrane anchor for kinesin on intracellular organelles. A kinectin isoform that lacks a major portion of the kinesin-binding domain does not bind kinesin but interacts with another resident of the endoplasmic reticulum, the translation elongation factor-1 delta (EF-1 delta). This was shown by yeast two-hybrid analysis and a number of in vitro and in vivo assays.

View Article and Find Full Text PDF