Friday, March 6, 2009 | If there is an issue that gets both scientists and lay people equally fired up, it’s human embryonic stem cells. Whether it is the incredible research advances they make possible, or the political fireworks they cause, stem cells are rarely a dull topic.
In the middle of it all is 39-year-old Travis Berggren, director of Salk Institute for Biological Studies’ stem cell core facility. The facility houses human embryonic stem cells, and supports the stem-cell research of scientists at Salk as well as other local research institutes.
Berggren worked for five years earlier this decade under University of Wisconsin cell biologist James Thomson, who is considered the father of stem-cell research. Last year, Salk lured Berggren back home (he grew up in San Diego) to start up the facility. He recently sat down with us to talk about a variety of stem-cell related topics from expectations of the Obama administration to bleeding-edge research in the field.
So where do the stem cell lines at your facility come from, and how many have been available to researchers since the federal funding ban has been in place?
Most of the lines now in existence are frozen balls of cells from in-vitro fertilization. (They are) pre-implantation embryos. … and the decision is to either throw them away or donate them to science. And this decision lies with the couples who created them. They are termed embryonic even though they were never growing inside a person.
Even the term embryo, which is officially correct, conjures images from the negative side, but really these are a ball of about 100 cells and they haven’t become anything yet, and they’ve only been in the laboratory and frozen. There are officially 22 federally approved lines, but in practice only about a dozen that people actually work with.
Why are people only working with a dozen when there are 22 available?
There are still some challenges. These were all lines created before 2001 (when President Bush instituted the ban). Originally when the Bush restrictions were placed there, they thought there would be 70 lines — but it turned out that many of those just never got thawed out. And some that did get thawed out are not scaled up and ready to distribute to people.
Are these lines enough for everybody?
It is certainly enough to get started on a lot of questions, enough that we have learned a lot. We have made a lot of advances, but it is certainly not enough to begin to think that we can address any kind of reasonable clinical level of applications for these. These are all lines that were derived somewhat with first-generation techniques, only meant to be a research tool. For any therapeutic treatments or pharmaceutical screening techniques, we need a larger genetic diversity.
What is the state of the ban right now?
The state of the ban is that I think there has been an announcement from one of the president’s advisors that he is planning on moving on this fairly quickly. With that said, I think everyone understands that there are some very pressing other needs, shall we say, on the president’s desk right now.
I think that is probably why we haven’t seen anything yet. The other interesting tidbit you may have caught, is that the bill passed by the House and Senate (in 2006), but was President Bush’s first veto, that exact bill has come back up and is now being run through the House. … it will be interesting to see if that bill passes with the same support that it had (last time). In some ways I think it is very encouraging that it got such strong bipartisan support. But also, my guess is that bill got some votes from some Republican legislators knowing they had cover from the guaranteed veto, which one would not expect to be in place with the current administration.
There has been a lot of talk lately about scientists developing the ability to take an adult cell, like a skin cell, and essentially converting it back to an embryonic state. How close are we to being able to do this, and are we on the cusp of eliminating the need for embryonic stem cells — and therefore the controversy?
That is a real good question, and one that comes up a lot. We are not on the cusp of that right now, but things look really promising.
This reprogramming technology will in a lot of ways go further that what we have been able to do with human embryonic stem cells. And, specifically, for being able to make patient-specific and/or disease-specific therapies, and have a broad cross section of genetically diverse stem cells. Now, with that said, things are at very preliminary stage, the technology is very fresh.
Along those lines, while the Bush administration ban was in place proponents of stem-cell research loudly touted the possible advances and cures that could result — cures for Alzheimer’s, Parkinson’s and spinal cord injuries, to name a few. With Obama and Congress seemingly set to lift the ban, are you worried that expectations are too high, that people will expect the cures in a matter of months or years, rather than decades?
As a scientist you always hate to hear extreme statements whether they are on one side or other. And we’ve certainly heard a lot of extreme statements about the slippery slope, or terrible moral things that could happen if we support this kind of research.
But the flip side is also true. Saying that we could make Superman fly tomorrow if we only could lift the ban on stem-cell research, certainly isn’t well grounded in scientific discovery. The real fact is that it is extremely difficult to predict. New, novel, revolutionary discoveries by their nature come in incremental fashion. And the other thing is the potential is pretty widely accepted by most all credible scientists that this does offer really a tremendous ability for understanding diseases. We can work with these cells through the very early stages of neural development, for example, for neural degenerative diseases and for a whole variety of other problems. But, to take these cells to clinical applications, we really do have to proceed very carefully. Because sticking in a cell that has full potential to be everything without having understood or control that potential can certainly lead to problems.
— Interview by DAVID WASHBURN
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