Scientists say they've made a device in the lab that can mimic the human female reproductive cycle.
The researchers hope the device, assembled from living tissue, will lead to new treatments for many medical problems that plague some women, ranging from fibroids and endometriosis to infertility, miscarriages and gynecologic cancers.
The researchers described the device Tuesday in the journal Nature Communications and dubbed it the EVATAR. The name, they say, is a play on the word "avatar."
"An avatar is kind of a digital representation of an individual in a virtual environment," says Teresa Woodruff, a biomedical engineer in the department of obstetrics and gynecology at Northwestern University who helped create the system. "So when we thought about this synthetic version of the female reproductive tract we thought of the word EVATAR."
To create the EVATAR, the researchers used tissues from human fallopian tubes, a uterus and cervix donated by women who had undergone surgery.
The researchers placed each tissue type in separate plastic chambers that were connected through passageways that allow fluid to circulate among them.
One chamber contained ovarian tissue from mice because human ovarian tissue is difficult to obtain.
The device is about the size of a paperback book. It also includes human liver tissue to filter toxins from the system.
The researchers were able to trigger the system to produce the cascade of hormones that usually occur during a woman's 28-day reproductive cycle. The cycle culminated in the ovarian tissue releasing an egg.
"We were able to recapitulate the full menstrual cycle — a complete menstrual cycle," Woodruff says.
The scientists hope to use the system to learn more about the basic biology of how the female reproductive tract functions.
The researchers hope that one day such devices might be able to be tailor-made from the stem cells of individual women, to test the safety and effectiveness of new drugs for that individual.
"EVATAR allows us to think about all the organs kind of connected in a way that eventually we hope will be the future of personalized medicine," Woodruff says.
Lansing Taylor, director of the University of Pittsburgh's Drug Discovery Institute, who was not involved in developing the system, says it could be especially useful in research because of the complexity of the female reproductive system.
"It's a very important paper," Taylor says. "Human reproductive tissues and organs have been particularly difficult to investigate."
The scientists stress that they only want to use the EVATAR to study anatomy and try to develop new treatments.
But at least one bioethicist wonders if others may someday try to combine this kind of technology in worrisome ways with other advances in reproductive medicine.
"Certainly the technologies are rapidly moving forward where one could imagine these technologies being used to create a baby outside the womb in the laboratory," says Insoo Hyun, a bioethicist at Case Western Reserve University.
That would raise many ethical issues.
"If, hypothetically, you can fertilize an egg outside a body and carry it all the way to term outside the body, then who's responsible for this baby now?" Hyun says. He also stresses that scientists are nowhere near being able to do that yet.
In the meantime, the Northwestern researchers have already started to work on a male equivalent of the EVATAR.
They've created a system involving male testes and prostate tissue they call the "Dude Cube." They are working on a more complex system that would connect the Dude Tube to other parts of the anatomy — a system they dub the "ADATAR."
ARI SHAPIRO, HOST:
Scientists have created a device from living tissue that can mimic the female reproductive cycle. They hope their creation will help them find new treatments for medical problems that affect many women. NPR health correspondent Rob Stein has details.
ROB STEIN, BYLINE: The female reproductive system is complicated and hard to study. So a team of scientists decided to make something they hoped would help.
TERESA WOODRUFF: Well, we call this EVATAR.
STEIN: Teresa Woodruff is a scientist at Northwestern University.
WOODRUFF: So we use the EVATAR basically as a play on the avatar. So an avatar is kind of a digital representation of an individual in a virtual environment. And so when we thought about this synthetic version of the female reproductive track, we thought about the word EVATAR.
STEIN: But the synthetic version of the female reproductive tract isn't digital; it's made from real living tissue.
WOODRUFF: We have human fallopian tube, human uterus, human cervix.
STEIN: That was donated for research by women who had them surgically removed for some reason. In the EVATAR, the scientists connect the living tissue with mouse ovaries. Each organ is in a separate plastic cube.
WOODRUFF: We have a system that allows each of the organs to have a cube, basically, a area within almost a handheld device that allows the tissues to interact with the other tissues that are in neighboring cubes.
STEIN: And can recreate the complex cascade of hormones that occurs during a woman's normal monthly cycle.
WOODRUFF: We were able to recapitulate the full menstrual cycle, a complete menstrual cycle, a 28-day cycle in this platform.
STEIN: That even resulted in the ovaries producing an egg. So why are they doing this?
Well, to study the system and hopefully learn more about how the female reproductive system works and find new ways to treat all kinds of conditions - fibroids, endometriosis, infertility.
WOODRUFF: I think the big news here is that the way we've done cell biology for the last 50 years is going to be completely transformed.
STEIN: Experimental drugs, for example, could someday be tested on EVATARs tailor-made to individual women from their own stem cells.
WOODRUFF: The EVATAR allows us to think about all the organs kind of connected in a way that eventually we hope will be the future of personalized medicine.
STEIN: Other researchers agree. Christos Coutifaris is an expert on female reproduction at the University of Pennsylvania.
CHRISTOS COUTIFARIS: I think it's a relatively major breakthrough for something that may have tremendous applications in the future.
STEIN: Now, the researchers stressed that they only want to use EVATARs to study anatomy and come up with new treatments. But Insoo Hyun, a bioethicist at Case Western Reserve University, says that may not stop others from someday trying to take this kind of thing further.
INSOO HYUN: Certainly, the technologies are rapidly moving forward where one could imagine these technologies being used to create a baby outside the womb in the laboratory.
STEIN: And that would raise a long list of ethical issues.
HYUN: If hypothetically you can fertilize an egg of the body and carry it all the way to term outside the body, then who's responsible for this baby now?
STEIN: The Northwestern researchers say they have zero interest in anything like that, but they have started work on another system to mimic the male reproductive system. An early version is called the Dude Cube, and they have plans for something that goes even further called the ADATAR. Get it? ADATAR and EVATAR.
Rob Stein, NPR News.
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