A New Finding Brought Us Closer to Cultivating Human Organs In The Lab

Molecular genetics researchers at the Weizmann Institute of Science have discovered a way to culture human stem cells far sooner than previously possible.

In the study published in the journal Cell, the researchers demonstrated that very early human cells can be created and then successfully integrated into mice. This is thanks to their undifferentiated, or as researchers called it, naïve state, in which they can develop into any type of cell in the body — including other stem cells.

In addition to that impressive feat, they've found that the stem cells they created are considerably more competent, allowing them to combine and better integrate with their host environment.

This significantly raises the chances of creating a cross-species chimera, which allows cells from one creature to contribute to the growth of another.

The researchers also devised a method for boosting the efficiency with which these cells can merge, and such research could be utilized to transplant cells or organs from one animal to another, even from other animals to humans.

Tracing the study 

The study's roots go back to 2021 when Prof. Jacob Hanna and his team made history by infusing human stem cells into mice for the first time and demonstrating that they can successfully integrate into the developing embryos of mice. After eight years, the researchers decided to take their study a step further by attempting to produce an even earlier form of stem cells to be used in similar procedures.

To overcome a number of obstacles, the researchers turned off two more signaling pathways, resulting in naive human stem cells with a stable genome, few gene regulation flaws, and, most crucially, the capacity to differentiate flawlessly. They also altered a key gene involved in genome stability, and this resulted in stem cells that are not only competent but also competitive, which means they could integrate without causing harm to the host. This increased "the chances for a successful transfer by about fivefold compared to what we were able to do in the past," according to Hanna.

"If in the future we should wish to grow a pancreas in pigs for human transplantation, for example, we will have to take into account these massive evolutionary differences between species, beginning with mice and humans," Hanna said.  

While it will be some time before we are able to develop human organs in the lab for transplantation, this research on stem cells has brought us one step closer to that goal.