In Utero Stem Cell Transplants, Enzyme Replacement May Offer New Treatments for Deadly Metabolic Disorders – UCSF News Services

Microsopic image of stem cells transplanted in utero in mice
Stem cells transplanted in utero (green) engrafted into fetal mouse brain tissue. Image credit: Q-H Nguyen/MacKenzie lab.

Administering stem cell or enzyme therapy in utero may be a path to alleviating some congenital diseases that often result in losing a pregnancy, according to a new study in mice by UC San Francisco researchers, who showed that stem cells can enter the fetal brain during prenatal development and make up for cells that fail to make an essential protein.

Each year, about 24,000 women in the US lose a pregnancy. One of the major contributors to this problem is a group of congenital diseases that can cause a condition called hydrops, in which fluid accumulates in the fetus, often to a fatal extent.

“This group of vulnerable patients has been relatively ignored in the fetal surgery world,” said UCSF’s Tippi MacKenzie, MD, senior author of the new study and member of the Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, who has worked for a decade developing novel therapies for heritable diseases that can be treated before birth. “We know these patients could potentially benefit from a number of medical therapies. So this is our first foray into treating one of those diseases.”

The new study, published Feb. 26, 2020, in Science Translational Medicine, was aimed at exploring treatments for MPS7, also known as Sly syndrome, a disorder caused by a mutation in a single gene. In this disease the body’s cells lack an enzyme