The underlying cause of male infertility is unknown for 30 percent of cases. In a pair of new studies, researchers at University of California San Diego School of Medicine determined that the reproductive homeobox (RHOX) family of transcription factors — regulatory proteins that activate some genes and inactivate others — drive the development of stem cells in the testes in mice. The investigators also linked RHOX gene mutations to male infertility in humans. The mouse study is published September 27 by Cell Reports and the human study was published September 15 byHuman Molecular Genetics.

Using cell reprogramming techniques, scientists have managed to induce support cells in the retina to become stem cells capable of making new neurons. They suggest the technique could lead to new treatments for glaucoma, macular degeneration, and other eye diseases where retinal neurons are lost.

In cases of severe ocular trauma involving the cornea, wound healing occurs following intervention, but at the cost of opaque scar tissue formation and damaged vision. Recent research has shown that mesenchymal stem cells (MSCs) — which can differentiate into a variety of cells, including bone, cartilage, muscle and fat cells — are capable of returning clarity to scarred corneas; however, the mechanisms by which this happens remained a mystery — until now. In a study published online today in Stem Cell Reports, researchers from Schepens Eye Research Institute of Massachusetts Eye and Ear have identified hepatocyte growth factor (HGF), secreted by MSCs, as the key factor responsible for promoting wound healing and reducing inflammation in preclinical models of corneal injury. Their findings suggest that HGF-based treatments may be effective in restoring vision in patients with severely scarred corneas.

A research team led by investigators at The Saban Research Institute of Children’s Hospital Los Angeles has generated functional human and mouse tissue-engineered liver from adult stem and progenitor cells. Tissue-engineered Liver (TELi) was found to contain normal structural components such as hepatocytes, bile ducts and blood vessels. The study has been published online in the journalStem Cells Translational Medicine.

When a person has a stroke, blood flow to the brain is interrupted, causing brain cells to die within minutes due to lack of oxygen. In some cases, this can result in paralysis, speech and language problems, vision problems, and memory loss. But in a new study, researchers have shown that stem cell therapy increases nerve cell production in mice with brain damage due to stroke.

A new study has determined the existence of at least four separate subtypes of human insulin producing beta cells that may be important in the understanding and treatment of diabetes. The findings are published online in Nature Communications.

An alternative to hip replacement surgery may be in sight. In the Proceedings of the National Academy of Sciences, researchers reveal how it may be possible to use a patient’s own stem cells to grow new cartilage in the shape of a hip joint.

Researchers from the University of Nottingham and the Wyss Institute at Harvard University have developed therapeutic synthetic, light-curable, biomaterials for dental treatments that support native dental stem cells inside teeth to repair and regenerate dentin.

Satellite cells are stem cells found in skeletal muscles. While transplantation of such muscle stem cells can be a potent therapy for degenerative muscle diseases such as Duchenne muscular dystrophy, these cells tend to lose their transplantation efficiency when cultured in vitro. In the study, published in the current issue of the Journal of Neuromuscular Diseases, researchers have found that treating these stem cells with leukemia inhibitory factor (LIF) effectively maintains the undifferentiated state of the satellite cells and enhances their transplantation efficiency.

A phase II clinical trial in people with amyotrophic lateral sclerosis (ALS), or Lou Gehrig’s disease, suggests that transplanting human stem cells into the spinal cord may be done safely.