Mimicking biological processes in the lab is becoming more common as the development of “organ-on-a-chip” technology intensifies. Now for the first time ever, researchers have managed to replicate the 28-day menstrual cycle of the human female reproductive tract in a dish.
The impressive study, published in Nature Communications, worked by combing five different tissue types within the organ-on-a-chip technology about the size of a human palm. The five tissue types used were actually derived from both humans and mice. While the fallopian tubes, endometrium (the tissue that lines the uterus), cervix, and liver tissues all came from humans, the researchers had to use mouse ovaries, as human ovary tissue is not easy to come by.
As the hormones estradiol and progesterone are identical in all species, there was not perceived to be any issue in mixing the tissue types used as the outcome should be the same regardless, explained co-author Teresa Woodruff, to IFLScience. After culturing the tissues, the researchers then added the pituitary hormone FSH to the media to induce the mouse ovaries to stimulate follicle cells, which in turn secrete the necessary hormones that then influence the menstrual cycle.
Four of the five tissue types used, and where they are naturally located. L. Mckinnon
They were able to get the five tissues to survive for the 28 days it takes for a full cycle of menstruation to occur, and recorded the changes that happen when different hormones are released, just as it occurs naturally. They found that oocytes (egg cells) were produced in the ovary tissue, and while they could not move, the hormones released did induce the fallopian tube cilia to change their beating exactly as happens in vivo to facilitate this.
In order to achieve this, the researchers had to find a way to mimic the natural interplay that occurs between the different tissue types when in the body. They did this by using microfluid technology, which allowed them to precisely control the flow of fluid containing essential chemicals along channels within the tissue, as well as its volume.
“Most cells are maintained in static culture, which means they are largely bathed in their own metabolic waste for long periods of time,” Woodruff told IFLScience. “The fact that media is moved between the tissues enables nutrients to be brought in and metabolic waste to be eliminated –similar to what happens in our organs through capillaries and the vasculature.”
Now that the full menstrual cycle has been replicated, including all the hormones involved, the team wants to use it to study new categories of contraceptives, said Woodruff. It could also be used to explore specific cancers – such as ovarian, endometrial, and cervical – that are also under the influence of hormones.