Abstract: Visual performance, to a large extent, depends on the optical and refractive properties of the eye. The cornea is of great importance to this system. However, it requires a healthy epithelium for protection and optimal functioning. A sophisticated apparatus which relies on unipotent stem cells ensures the homeostasis of the corneal epithelium. A number of pathologic conditions can damage this mechanism, thereby compromising the ocular surface. This article will examine the concepts underlying a healthy or diseased corneal surface. Subsequently, current therapeutic approaches to regenerate a healthy epithelium and potential future developments will be discussed. ... Read more

Stem cells modulate tissue formation and repair based on a complex interaction of cell autonomous and non-autonomous regulatory mechanisms. While reductionist approaches to understanding stem cell control continue to be extremely productive, understanding the physiological contexts in which stem cells function, will ultimately require definition of the microenvironments in which they live. The location of stem or precursor populations within numerous solid tissues has been described, but delineating specific associated cells and how they participate in regulating stem cell function has generally been lacking for mammalian tissues. However, the use of invertebrate-based models has created particularly productive systems in which ... Read more

Stem cells have enormous therapeutic potentials. As of today, however, they remain as a “loose cannon.”

Scientists and clinicians are attracted to stem cells’ potential to divide and differentiate. There are, however, numerous hurdles to cross in order for stem cells to have safe, reliable, and predictable therapeutic benefits. Chief among the hurdles are the difficulty in harnessing the stem cells to differentiate into the right kind of functional mature cells and behave like normal differentiated cells.

Drs. Tsai and McKay of National Institutes of Health reported recently that they discovered a novel protein, nucleostemin, that is found in both stem cells ... Read more

Abstract: Human blood stem cell-derived insulin-producing cells can be easily isolated from autologous blood based on their unique phenotype. They act as pancreatic islet beta-cell progenitors, as demonstrated by authentic insulin production and homing to diabetic pancreatic islets. Clinical application of these autologous blood-derived insulin-producing cells holds great promise for diabetic treatment. ... Read more

Abstract: Adult human mesenchymal stem cells (hMSCs) are the focus of a number of clinical applications. The advantage of hMSCs is that they are immuno-modulatory and versatile due to their secreted bioactive molecules that are anti-inflammatory and regenerative. These cells have the potential to orchestrate reparative processes in diseased or injured tissues. Much of the diversity and uniqueness of hMSCs is defined by their response to the milieu of injured tissue. hMSCs are sensitive to their site-specific microenvironment, and it is anticipated that they will deliver the bioactive agents in a site-specific manner quite different from the way pharmaceutical drugs work. This review highlights current concepts of such functions with a focus on the clinical utility of hMSCs in the treatment of lung diseases. ... Read more

Abstract: Adult mesenchymal stem cells (MSCs) are non-hematopoietic cells with multi-lineage potential to differentiate into various tissues of mesodermal origin. They can be isolated from bone marrow and other tissues and have the capacity to extensively proliferate in vitro. Moreover, MSCs have also been shown to produce anti-inflammatory molecules which can modulate humoral and cellular immune responses. Considering their regenerative potential and immunoregulatory effect, MSC therapy is a promising tool in the treatment of degenerative, inflammatory, and autoimmune diseases. However, the current understanding from results of clinical trials is that MSC-therapy is safe but its therapeutic efficiency needs to be improved. In this article we will focus on options for genetic manipulation of MSCs and on current progress in adapting genetically-modified MSCs for clinical use in acute cardiovascular disease. ... Read more

Abstract: Human gene therapy has made substantial progress since the initiation of the first clinical trials 20 years ago. Here, we summarized important applications of gene transfer protocols in the treatment of various human diseases using different viral vectors. Recent successful trials on the treatment of ocular diseases and inherited immune deficiencies are particularly encouraging and have raised hopes that human gene therapy as a standard treatment option will finally become a reality. While immune responses and insertional mutagenesis pose obstacles for this novel form of molecular medicine, continuous progress suggests that a wider range of diseases can be treated with gene therapy in the future. ... Read more

Abstract: Due to ethical concerns, human embryonic stem cells have limited availability and practical usefulness. Adult stem cells are present within tissues of adult organisms and are responsible for cell turnover or repopulation of tissues under normal or exceptional circumstances. Multi-potent stem cells have been isolated from the umbilical cord blood and they offer promising therapeutic potentials. ... Read more

Abstract: Human adult bone marrow-derived multipotent stem cells (BMSC) can grow to become virtually any cell type, under the right conditions. Heart muscle cells differentiated from BMSC are shown to be able to repair lesions caused by a heart attack. ... Read more

Abstract: Many people carry electronic pacemakers and, generally speaking, these devices work quite well. However, they do not automatically adjust heart rates in response to special circumstances, like exercise or emotion. Stem cells isolated from adult bone marrow can be genetically engineered to behave like the heart's own natural pacemaker cells. These stem cells can grow and integrate with native surrounding heart muscle cells, allowing the heart to react more naturally to their surroundings. ... Read more