A stem cell by any name

This past year has brought a number of advances in creating reprogrammed iPS cells and in directly reprogramming mature cells into a different cell type. With each advance comes the question: Where does this leave embryonic stem cells? And each time, stem cell scientists remind us that the advances are great and could potentially lead to exciting therapies, but there’s a lot to learn in terms of safety.

An AP story today has a great quote from George Daley of Children’s Hospital Boston and the Harvard Stem Cell Institute, whose lab has been responsible for many of those advances:

When we make a duck look like a cat, it may look like a cat and meow, but whether it still has feathers is an issue.

It was a good weekend for analogy. CIRM grantee Paul Knoepfler at UC Davis came up with this one on his blog:

If ES cells are like a safety and road tested Ford (a model that’s been around a dozen years), then IPS cells are a shiny new sports car that even the experts know very little about. We are not sure how its accelerator or brakes work. It hasn’t been crash tested. It looks really fast and everyone thinks it has a lot of potential, but it’s only been around a very short time.

If you had to get you and your loved ones safely from point A to point B, which kind of car would you go in at this time?

IPS cells have outstanding potential, but they are still somewhat of a mystery, particularly in terms of their safety. I predict that in a few years, there will be safe iPS cells, but we aren’t there yet. We just don’t know enough.

A comment on Knoepfler’s blog points out:

I would say that adult stem cells are cadillacs: been around a long time, you know what you are getting, solid

Depending on which analogy you prefer, CIRM funds either an entire zoo, or a full parking lot. Here’s my own analogy: Some diseases are more like mountain passes and require a sure-footed SUV. Others are winding highways ideal for racing. CIRM grantees are test-driving all types of stem cells with the goal of learning which provides the best transportation to a cure for different diseases. If all we have are Cadillacs we’ll have a hard time with diseases that require a space-saving Smart car.

You can filter our list of all funded stem cell research awards according to the stem cell type being used.

A.A.