Whose life is it anyway? Building patient needs and goals into stem cell clinical trials

by Lisa Willemse

In a traditional view of medical research, advances tend to be measured against the overarching goal of cure. Noble as this might be, research is rarely such a black and white affair -- if we have learned anything, it’s that there are innumerable shades of grey.

Even the goal itself can be questioned, especially when achieving it could be 50 years into the future.

17-year-old high school student makes a cancer stem cell breakthrough

When we report on breakthroughs in stem cell research, we typically link to well-funded studies published in peer-reviewed journals by world-renowned scientists. This time, it’s a little different.

Angela Zhang, a high school senior from Cupertino, California, was awarded a $100,000 scholarship for her submission to the 2011 Siemens Competition in Math, Science & Technology: A “gold and iron oxide-based nanoparticle” designed to seek out and destroy tumour-causing cancer stem cells.

The apple of a bioengineer’s eye: mature photoreceptors

by Angela C.H. McDonald

Last spring, I wrote about the remarkable generation of self-organizing retinal tissue created from mouse embryonic stem cells. The study successfully created all major retinal components including photoreceptors, albeit at a low abundance. However, while multi-layered optic tissue did form, the alignment and organization of mature retinal cell types differed from that of the mouse eye in vivo.

The missing ingredient in this experiment was a physical, instructive cue to direct retinal cells into the complex structural pattern of the eye. 

A recent paper published in Biomaterials by another group of researchers described a biomaterials-based approach for creating organized photoreceptor cells from human embryonic stem cells.

Human embryonic stem cells were differentiated into retinal cells and seeded onto a specially designed scaffold positioned on top of a retinal pigment epithelial cell layer. This resulted in the organization of cells into a complex retinal architecture.

Tick, tock, clock – the clock is ticking for you

by David Kent

From the depths of the poetic frivolity of Raphael de la Ghetto come some words that might help guide us through one of the most interesting concepts being pursued by stem cell biologists these days.  Specifically, research has emerged which links stem cell behaviour and fate choices to circadian rhythm. The group of Salvador Aznar Benitah in Barcelona recently published research which links skin stem cell turnover and heterogeneity to the body’s internal clock. Their work has inspired many new studies that aim to understand the impacts of circadian rhythm on other stem cell systems. 

In tissues that have high turnover (such as the skin, gut, and blood), daily oscillating changes in the balance between making more stem cells (self-renewal) vs. more specialized cells (differentiation) seems a reasonable method for regulating cell number and type. Whether or not these effects are occurring in the stem cells themselves is not fully understood, as stem cells are often regarded as a reservoir of inactive cells that are typically only used when other cell types are in high demand. Furthermore, scientists have known about Clock and Bmal1, two proteins that play a leading role in circadian pacemaking, since 1994 and 2000 respectively, but a strong link to stem cell fate choice had not been made until this paper.