Duke Researchers to Create Images of Human Embryo Development
DURHAM, N.C. -- Images of the earliest stages of human
development are beginning to emerge in detail never seen before
thanks to the power of magnetic resonance microscopes developed
by researchers at the Center for In Vivo Microscopy at Duke
University Medical Center.
The images of intact human embryos smaller than a pencil
eraser are being created with funding from a four-year, $1
million contract with the federal Institute of Child and Health
and Human Development, part of the National Institutes of
Health. Sample images already are available on the Internet,
with many more to come throughout the contract period.
The Duke researchers are using magnetic resonance
microscopes to create three-dimensional human embryo images
that reveal details of the developing brain, bones, organs and
other features. The microscopes create images of the internal
organs and tissues using a strong magnetic field and computer
graphics. The result will be a permanent, interactive image
reference that will provide the first-ever three-dimensional
chronological record of intact embryos. The completed atlas
will allow doctors and teachers to watch the development of the
various organs and systems from all angles. The image data will
be available free of charge on the Internet.
Duke developmental biologist and imaging specialist Bradley
R. Smith will create the atlas using the resources of Duke's
Center for In Vivo Microscopy, a National Center for Research
Resources-sponsored facility. The embryos, ranging from 11 days
to three months of gestation, will come from the Carnegie
Collection of Human Embryos, housed at the National Museum of
Health and Medicine in Washington, D.C. This collection
includes preserved embryos that were obtained by physicians
"This project will provide a unique resource that will
greatly improve our ability to visualize the earliest stages of
human development," Smith said.
The project will complement the already-completed "visible
human" project, a similar computerized atlas of an adult man
and woman that is available on-line for teaching and research,
he said. That project was sponsored by the National Library of
The embryo images will advance medical science in several
ways, according to Smith.
"The human genome project and the prospect of gene therapy
are now making it realistic to think about correcting defects
in developing fetuses," said Smith, whose own research focuses
on development of the heart and blood vessels in a mouse model.
"Some steps are already being made in fetal surgery. What has
been lacking is a reference tool based on modern imaging to
help physicians see what a normal developing human should look
Today, when doctors want to see what the organs or tissues
of a normal developing embryo look like, they must undertake
the laborious and time-consuming task of sorting through
hundreds and sometimes thousands of individual histological
slides, each representing a paper-thin slice.
"It's like looking at hundreds of thin slices of bread
individually and trying to visualize how they fit together to
make a loaf," Smith said.
He emphasizes that this project will provide a
widely-available resource for research and teaching that will
reduce the need to gather data from additional human embryos,
and it will simultaneously preserve valuable anatomical
information on existing preserved embryos.
Dr. Dale Huff, a pediatric pathologist at the University of
Pittsburgh, is collaborating with Smith on the project. He said
that this resource may aid diagnosis of abnormalities in
miscarried embryos and help physicians and families understand
why a woman lost a pregnancy.
The human embryo atlas will be created by placing each
intact embryo in a magnetic resonance imaging (MRI) device
specially designed at Duke to create images of tiny specimens.
The MRI devices used in hospitals are not powerful enough to
see inside a tiny animal, or in this case, a tiny human embryo.
Smith will take thousands of individual pictures of each embryo
and the computer will combine the individual pictures into a
three-dimensional image that can be manipulated on the computer
screen. Sophisticated computer graphics will allow researchers
to, for example, fly through a three-dimensional circulatory
system or make the skin transparent so the developing skeleton
is clearly visible.
Smith has already created a similar tool for developmental
biologists who study mouse embryos. The mouse atlas is a daily
chronicle of each stage of mouse development starting at 9.5
days after conception, when the developing embryo is no bigger
than the head of a pin, continuing for 20 days to birth. Smith
created the mouse atlas in collaboration with Duke
developmental biologist Elwood Linney, and G. Allan Johnson,
director of the Center for In Vivo Microscopy. Funding for the
mouse atlas was provided by the North Carolina Biotechnology
Center and the National Institutes of Health.
Smith said the two projects may even work together.
"Years of research in animals, such as mice, have begun to
provide valuable knowledge about how embryos develop and what
can go wrong that results in birth defects," Smith said. "We
hope the human atlas will serve the same purpose for doctors
and researchers who may not be familiar with how a human embryo