Human Muscles Grown in Pig Embryos for the First Time

Volumetric muscle loss refers to when skeletal muscle tissue has been damaged so badly that it is incompatible with grafts post-mortem muscle tissue. This makes post-mortem organ donations impossible and for a long time has had no solution until now...

The University of Minnesota is developing human-pig chimeras (organisms that include two or more sets of DNA) that allow human muscles to grow in pig embryos. The development, that uses CRISPR, could be revolutionary for healthcare.

“VML often occurs due to accidents, surgical resection of large tumors, and servicewomen and men in combat,” co-author Mary Garry, an associate professor of medicine at the University of Minnesota’s Cardiovascular Division, told Inverse.

“There is no good therapy for VML and the result is limb loss and/or lifelong disability due to lost muscle function. The advance of generating human skeletal muscle in pigs has great promise for benefiting the surgical repair and return of function of VML.”

So what exactly makes this advance so different? Instead of growing human organs in their chimeras, the researchers developed human muscle tissue that could be used to repair sites of muscle loss inside the pigs.

However, the experiment does raise questions about the possibility of having created sentient pigs with human consciousness. Garry addressed this concern when speaking to Inverse.

“It is important to note that we demonstrate that the human donor cells are located only where the pig skeletal muscle [now genetically deleted] once was,” Garry explained. “The human donor cells do not migrate to the brain or to the reproductive cells of the pig.”

“This information serves to allay important ethical concerns surrounding the production of chimeras,” she added. Garry now hopes to start clinical trials of these organ and tissue transplants in the next three to five years. The study was published in the journal Nature Biomedical Engineering.