The Virtual Embryo Project
EPA researchers are developing a "Virtual Embryo" that will provide insights into how exposures to chemicals in the environment might affect the developing embryo.
The development of an embryo, from conception to birth, includes a highly coordinated sequence of cellular behaviors and interactions. While that process goes perfectly the vast majority of the time, at least three percent of babies are born each year with some observable malformation or developmental condition that may permanently shape the life of the child.
What role does a pregnant woman’s exposure to chemicals in the environment play in disrupting the development of an embryo? Scientists in the U.S. EPA’s computational toxicology research program are developing new ways to answer that question. And in the process they are helping revolutionize the field of developmental toxicology.
The traditional method of exploring how chemicals affect a developing embryo is conducting controlled tests on pregnant laboratory animals. While these practices provide valuable information, they can be both costly and slow. Reliance on them is one reason the pace of testing has not kept up with the development of commercial chemicals, leaving significant data gaps.
EPA scientists are carrying out a research program—the Virtual Embryo Project (v-Embryo™)—aimed at developing new methods that use high-tech computer modeling and vast collections of data and biological knowledge bases in place of traditional lab tests.
“The ultimate objective is to build a suite of screening models, a toolkit, that researchers can use to look at embryonic development and make scientifically-based predictions on how that development might be affected by different chemicals,” says Thomas B. Knudsen, Ph.D., an EPA systems biologist who is leading the project. “We are building models that properly integrate all the relevant data and information known about various organ systems and birth defects.”
Using a selection of everyday chemicals with known health effects in animals, Knudsen and an interdisciplinary team of reproductive toxicologists, computer engineers, programmers, bioinformaticians, biologists, mathematicians, and other experts are working to build computer-based virtual models of embryo development.
“Computer models can handle this complex information, and it is feasible with current math and engineering practices to use these models as a new approach for predicting the potential for environmental chemicals to affect a developing embryo,” explains Knudsen.
To start, Knudsen and his partners chose to develop computer models for embryo systems that are well documented, susceptible to environmental factors, and simple enough that computer engineers and programmers can simulate them. Three that fit the bill are embryonic eye, blood vessel, and limb development.
Once the embryo systems are simulated, the predictive value of these models will be tested. To do that, researchers will use new and existing data from standardized tests conducted in embryonic stem cells, zebrafish embryos, and ToxCast™, another EPA computational toxicology program.
The research team is made up of EPA scientists and outside partners, including contractors from Lockheed Martin and investigators from the Agency-funded Texas- Indiana Virtual STAR Center. Collaborators representing a wide range of expertise from across academia, industry, and other governmental agencies provide project data.Anyone with data or expertise to contribute, or who might want to partner with the v-Embryo team should contact Monica Linnenbrink (email@example.com or 919-541-1522).