The promise of stem cell research for drug discovery and cell-based
therapies depends on the ability of scientists to acquire stem cell lines for
A survey of more than 200 human embryonic stem cell researchers in the
United States found that nearly four in ten researchers have faced excessive
delay in acquiring a human embryonic stem cell line and that more than
one-quarter were unable to acquire a line they wanted to study.
“The survey results provide empirical data to support previously
anecdotal concerns that delays in acquiring or an inability to acquire certain
human embryonic stem cell lines may be hindering stem cell science in the
United States,” says Aaron Levine, an assistant professor in the School of
Public Policy in the Ivan Allen College of Liberal Arts at the Georgia
Institute of Technology.
Results of the survey were published in Nature Biotechnology.
Funding for the study was provided by the Kauffman Foundation’s Roadmap for an
Entrepreneurial Economy Program.
Levine administered the Web-based survey in November 2010 to more than 1,400
stem cell scientists working at U.S.
academic and non-profit medical research institutions. Almost 400 respondents
from 32 states completed the survey. Of those, 205 respondents reported using
human embryonic stem cells in their research, and their responses were used in
The surveyed scientists cited four main reasons for their problems accessing
human embryonic stem cell lines: difficulty obtaining material transfer
agreements, failure to acquire research approval from internal institutional
oversight committees, cell line owners that were unwilling to share, and
federal policy considerations.
“Bureaucratic challenges may be inevitable in this ethically
contentious and politically sensitive field, but policymakers should attempt to
mitigate these issues by doing things like encouraging institutions to accept
third-party ownership verification and providing clearer guidance on human
embryonic stem cell research not eligible for federal funding,” says
Levine, who is also a member of the Georgia Tech Institute for Bioengineering
The broad patents assigned to the initial inventors of the method used to
isolate embryonic stem cells and numerous narrower patents claiming specific
human embryonic stem cell-related techniques are also factors complicating
access to human embryonic stem cell lines, according to Levine.
When survey respondents were asked how many of the more than 1,000 existing
human embryonic stem cell lines they used, 76% reported using three or fewer
lines and 54% reported using two or fewer lines in their research. More than
half of the 130 respondents cited access issues as a major reason they chose to
use specific cell lines in their research.
“These results illustrate that many human embryonic stem cell
scientists in the United
States are not conducting comparative
studies with a diverse set of human embryonic stem cell lines, which raises
concern that at least some results are cell-line specific rather than broadly
applicable,” says Levine. “Federal and state funding agencies may
want to consider encouraging research using multiple diverse human embryonic
stem cell lines to improve the reliability of research results.”
Embryonic stem cell lines are being used to develop new cellular therapies
for various diseases, to screen for new drugs and to better understand
inherited diseases. It’s crucial that diverse lines are available for this
research to ensure that all individuals benefit from the results.
While availability was cited as the most common factor affecting scientists’
choices regarding which cell lines to use, other considerations included
suitability for a specific project, familiarity with specific lines, a desire
to reduce complications in the laboratory, cost, the extent of relevant
literature and the preferences of scientists’ colleagues.
Three of the initial human embryonic stem cell lines derived at the University of Wisconsin in the late 1990s were the
lines most commonly used by respondents. Cell lines H1, H9, and H7 were used by
79, 68, and 26% of respondents, respectively. Scientists also reported using
more than 100 other lines, but each of these was used by fewer than 12% of
“Other research communities in the life sciences have experienced
material access problems and they addressed them, in part, by creating
centralized information and data sharing hubs, including public DNA sequence
databases, tissue banks and mouse repositories. The stem cell research
community has taken promising steps in this direction, but this analysis should
encourage the community to continue and, if possible, accelerate these
efforts,” adds Levine.
Filed Under: Drug Discovery