Fetal tissue has led to vital biomedical research advances, but new restrictions may severely curb both its use and scientific progress, says UCSD distinguished professor Lawrence S. B. Goldstein.
Fetal tissue has been used in biomedical research for decades, contributing to advances in vaccine development and HIV drug testing. Current research into macular degeneration, multiple sclerosis, spinal cord injuries, and Parkinson’s could lead to therapies that could improve the lives of millions of patients. But new federal restrictions on the use of fetal tissue, which become effective Sept. 25, will halt some studies and have a crippling effect on others.
In June, the U.S. Department of Health and Human Services (HHS) announced new rules that discontinue research within the National Institutes of Health (NIH) that involves human fetal tissue from elective abortions and requires that NIH-funded research involving human fetal tissue that is conducted at academic health centers be subject to a lengthy approval process.
AAMCNews spoke with Lawrence S. B. Goldstein, PhD, distinguished professor at the University of California (UC), San Diego, School of Medicine and founder and former director of the Sanford Stem Cell Clinical Center at UC San Diego Health, about how scientists use fetal tissue and what the new restrictions mean for the future of biomedical research.
For what areas of biomedical research is the use of fetal tissue particularly important?
Cells derived from fetal tissue have been critical in vaccine development. Numerous vaccines have been developed using fetal cells developed by [renowned researcher] Leonard Hayflick and others who followed in his footsteps.
Fetal tissue is also vital to areas of stem cell research because it helps us prove that the cells we’ve made are actually the cell progenitors of the organs we’re trying to build or the structures within those organs we’re trying to build. So fetal tissue is the gold-standard comparison in a variety of areas that use stem cells to make cells or tissues for replacement or research.
Those are the two biggest areas. A third would be the use of so-called humanized mice, where fetal tissue is used to make mice that have completely human blood-forming and immune cell-forming tissues so that drugs can be tested against HIV, for example, or research can be done on a variety of hereditary blood diseases and immune diseases.
What makes fetal tissue unique?
Some have argued that it has better growth potential in culture. But I think the most valuable part is that fetal tissue provides very early organ tissue that can be used for research, so early kidney tissue, early brain tissue, or early immune-forming tissue.
When we use stem cells, sometimes we’re not entirely sure we’ve made pure populations of cells or that we necessarily have made the right kind of cell, so getting at the so-called progenitors of different organs and tissues is vital.
What are some common misconceptions about fetal tissue?
There are two incorrect statements about fetal tissue research. The first is that we know enough about stem cells that appropriate alternatives to fetal tissue can be developed now. The fact is, stem cells can do a lot of things. But there’s very clear evidence in the scientific literature and presented at scientific meetings that establish that stem cells are not yet at the point where they can completely replace fetal tissue. In fact, the development of all alternatives using stem cells will require fetal tissue to validate that stem cells have made the right cell types.
The second incorrect statement is that all of these vaccines could have been developed using nonhuman cells, such as monkey cells, and that’s also just not true. One of the problems with the use of monkey cells, for example, that’s emerged from reviews of the history is that they often carry viruses that are potentially toxic to humans, and the human cells seem to lack those viruses.
Meredith Wadman, MD, recently wrote a book about the history of vaccine development called The Vaccine Race: Science, Politics, and the Human Costs of Defeating Disease. It’s really very clear that fetal tissue was vital to the development and the continued production of vital vaccines that have saved millions and millions of lives. So it’s an incorrect statement to say, Oh, we didn’t need fetal cells in the development of vaccines. That’s also nonsense. The history is clear.
How has fetal tissue made your own research possible?
The best example comes not from my own lab but from work we’ve done in the Sanford Stem Cell Clinical Center. One of the clinical trials that’s ongoing is the use of fetal spinal stem cells to treat spinal cord injury. These cells have provided striking results in rats for spinal cord injury, and they’re now in phase one human clinical trials. And a few of the patients seem to be doing better.
This is remarkable because spinal cord injury is an injury for which there’s almost no effective treatment, and is unfortunately common, and its victims suffer terribly during their lives. We need more clinical trial data to really ascertain what’s going on. We have to continue using these fetal cells in spinal cord injury victims to see if we can truly develop a therapy. But the results are very promising in the early stages.
Which aspects of these new restrictions are going to put the greatest burden on researchers?
One of the big problems is that a very long detailed justification for fetal tissue needs to be provided as part of the research strategy part of the application and NIH limits the number of pages you can have in that part of the application. Not only do you have to provide a lengthy justification for the use of fetal tissue … it [also] crowds out a lot of the actual scientific part of the application.
A second potential problem is, if you have an existing [NIH Research Project Grant], and you make a discovery that requires some simple experiment with fetal tissue, you can’t just go ahead and do it with the NIH funds. You have to write a completely new grant application that needs to go through competitive review and then the HHS ethics review board … before you can do what is a simple experiment. It will slow down the progress of science in areas that may unexpectedly and appropriately require the use of fetal tissue for some straightforward experiments.
The third problem is the grants will all be exposed to duplicate review in a sense. [A grant will go to] the initial review group, which will review the fetal tissue justification and the science. Then it’ll go to the NIH Council. This is all standard so far. But then it goes to the ethics review board of HHS, which in its current description, reviews not only the ethics, but also reviews the scientific justification again. It’s completely redundant and a waste of time and it’s not going to gain any additional quality of review of the science.
What do you foresee as the impact of these restrictions on early career scientists?
There’s been some discussion of whether or not trainees supported by NIH training grants can participate in fetal tissue research. I’d say that the current situation is that it’s murky. Many of us think that the way NIH has described which kinds of grants can use fetal tissue precludes trainees, such as graduate students and postdocs. NIH has countered, but I don’t think the situation is so clear given how it’s written.
If I were an investigator with a graduate student on an NIH training grant, I sure wouldn’t let them work with fetal tissue, given how unclear the rules are and concerns about being audited and told that we did something inappropriate. That’s not something I would be prepared to risk. We effectively preclude trainees supported by NIH training grants or research fellowships from participating in fetal tissue research and learning how to do it appropriately from their mentors.
Why should the academic medicine community be concerned about these new restrictions?
A very important goal of biomedical research is to develop new medical therapies as rapidly as possible for patients who suffer from terrible diseases. When we place these restrictions on important areas of research, we slow down the hunt for understanding and the development of new therapies for the patients of physicians, both in academic health centers and out in the regular community.
By Julia Haskins, Special to AAMCNews