Researchers have grown mini-organs from cells shed by fetuses in the womb in a breakthrough that promises to shed light on human development during late pregnancy.
They created the 3D lumps of tissue known as organoids from lung, kidney and intestinal cells recovered from the amniotic fluid that bathes and protects the fetus in the womb.
This is the first time such organoids have been made from untreated cells in the fluid and paves the way for unprecedented insights into the cause and progression of malformations, which affect 3-6% of babies worldwide.
Dr Mattia Gerli, a stem cell researcher at UCL, said fetal organoids, which are less than a millimeter wide, would allow scientists to study how fetuses develop in the womb “in both health and disease”, an achievement which has not been done so far. possible.
Because the organoids can be born months before a baby is born, scientists believe they can drive more personalized interventions by helping doctors diagnose any defects and work out how best to treat them.
Organoids are small clumps of cells that mimic to a greater or lesser extent the characteristics and functions of larger tissues and organs. Scientists use them to study how organs grow and age, how diseases progress, and whether drugs can reverse any damage that occurs.
Most organoids are made from adult tissue, but researchers have recently made them from cells obtained from fetuses. The most ethically sensitive are created from tissue collected from terminated fetuseswhile others are made by reprogram cells in a more embryo-like state.
Write in Naturopathy, Gerli and Prof Paolo de Coppi, a fetal surgeon at Great Ormond Street Institute of Child Health, describe how they analyzed amniotic fluid taken from 12 pregnant women as part of their routine diagnostic tests. Most of the cells in the amniotic fluid were dead, but a small fraction were stem cells for making the baby’s lungs, kidneys and intestines. The researchers found they could grow them into 3D organoids by injecting them into drops of gel and growing them.
To investigate how the organoids could be used, the team created lung organoids from the cells of unborn babies with a condition called congenital diaphragmatic hernia, or CDH. Babies with CDH have a hole in the diaphragm, the dome-shaped muscle below the lungs that powers breathing. The hole allows organs in the abdomen to push up on lungs and stunt their growth.
Comparison of organoids from CDH infants before and after treatment showed significant differences in their development, indicating a clear benefit of the treatment. “This is the first time we have been able to make a functional assessment of a child’s congenital condition before birth,” said De Coppi.
The same approach can investigate other congenital conditions, such as cystic fibrosis, which causes mucus to build up in the lungs, and malformations in the kidneys and intestines. Drugs that help alleviate congenital disorders could be tested on the organoids before they are given to the babies, De Coppi said.
Roger Sturmey, professor of reproductive medicine at the University of Hull, said the research paved the way for scientists to study how key organs in unborn babies form and function without tissue donated to research after an abortion. “It may also reveal the early origins of adult diseases,” he said, “by highlighting what happens when the cells of key tissues within fetuses malfunction.”
