In another demonstration of the importance of niches in tissue regeneration, scientists at Britain’s University of Sheffield have used stem cells embedded into a biodegradable disk as a potential treatment for corneal blindness. Writing in Acta Biomaterialia, researchers led by engineering professor Ílida Ortega Asencio used a combination of techniques known as microstereolithography and electrospinning to create the disk, load it with stem cells and induce the cells to multiply. The same biodegradable materials have been previously used in the human eye, which causes investigators expect commencement of clinical trials “fairly quickly,” according to study team member Sheila MacNeil. See a video of the technique here.
A report in Nature describes a method of extracting cells capable of becoming neural cells from an unlikely source: urine. Duanqing Pei and coworkers at China’s Guangzhou Institutes of Biomedicine and Health and previously demonstrated the conversion of kidney epithelial cells from urine into iPS cells. That study involved retroviruses to confer pluripotency, which makes cells less predictable in a clinical setting. Here researchers introduced genes using vectors that did not integrate in the cellular genome. In one experiment, Pei et al. generated cells that resembled pluripotent stem cells after just 12 days – half of normal time.
The Institute of Medicine (IOM) is urging the California Institute for Regenerative Medicine (CIRM) to change its practices to address potential issues related to mismanagement and conflicts of interest. Created in 2004, CIRM has awarded $1.3 billion in grants to stem cell projects of the $3 billion approved by California voters. CIRM is governed by a 29-member board that includes scientists, industry leaders and patient advocates. IOM did not cite any specific conflicts of interest in its report, but noted that if such concerns were not addressed CIRM could lose credibility among scientists and the public. See related stories from the Nature News Blog, Los Angeles Times, or the full IOM report.
A paper in ACS Nano describes the first case of manipulation of the neural stem cell niche with nanoparticles that release retinoic acid, a pro-neurogenic agent. Manipulating niches could “open new perspectives for the treatment of neurodegenerative diseases,” said Dr. Lino Ferreira, lead investigator at the Biocant-Center of Innovation and Biotechnology in Portugal, where the work was done.
As reported in Nature Methods, Salk Institute scientists have developed a technique for producing stem cells which, by being faster and safer, promises to remove a significant barrier to regenerative medicine therapies. “One of the barriers that needs to be overcome before stem cell therapies can be widely adopted is the difficulty of producing enough cells quickly enough for acute clinical application,” said study author Ignacio Sancho-Martinez. Stem cells are derived either directly from pluripotent cells (e.g. embryonic stem cells), or from reprogrammed mature cells (induced pluripotent stem cells). The former carry ethical concerns, while the latter are difficult to produce in quantity. The new technique, “indirect lineage conversion” pushes cells back just far enough to make them suitable for specification into progenitor cells.
Alternative to stem cells? Washington University scientists have learned how to re-awaken the process by which new cells are created in the heart. Cardiac cells lose most regenerative capacity after birth, but four human microRNAs identified by Ana Eulalio and coworkers were shown to stimulate proliferation of cultured rat heart cells and protect them from damage during heart attack in vivo. If the microRNAs work similarly in humans, they could initiate repair of hearts damaged by disease. The work was reported in Nature.
Business Briefs: Celldex Therapeutics has announced positive results from a Phase 1 study of CDX-301 (FMS-like tyrosine kinase-3 ligand), which mobilizes hematopoietic cell populations. With the therapeutic agent well-tolerated in healthy volunteers, the company is ready to move forward in such indications as hematopoietic stem cell transplantation and cancer immunotherapy… Adaptimmune has achieved encouraging preliminary results from an early phase clinical study using patients’ own T cells that have been genetically altered to attack multiple myeloma cells. The study demonstrated safety and bioactivity for patients who received an autologous stem cell transplant for multiple myeloma…Neuralstem has demonstrated that long-term immunosuppression is unnecessary for the long-term efficacy of its stem cell treatment of amyotrphic lateral sclerosis (ALS)…Related topic: Interview with Brainstorm Cell Therapeutics CEO Dr. Adrian Harel on his company’s take on stem cell-based ALS treatment…Ten pharmaceutical firms and 23 European universities will develop a stem cell bank through a project initiated and coordinated by the Oxford University and Roche. The bank will receive 55.6 million Euro ($72 million) over five years, with €26 million from the European Union’s Innovative Medicines Initiative…Similarly, Serbia will open its first stem cell bank in late 2013 or early 2014.