A combination of CRISPR/Cas9 genome editing and blastocyst complementation was used to produce mouse lungs in rats for the first time.

Research conducted at the Phoenix Children’s Research Institute at the University of Arizona College of Medicine — Phoenix reports the successful generation of a mouse lung in a rat, according to a paper published in the American Journal of Respiratory and Critical Care Medicine.

“By using a combination of genome editing and blastocyst complementation—a process of injecting murine embryonic stem cells into blastocyst-stage embryos in rats—our research team successfully produced mouse lungs in rats, which is a significant step toward the development of future generations of human lungs,” says Vlad Kalinichenko, MD, PhD, a lung development and regeneration researcher and director of the Phoenix Children’s Research Institute at the University of Arizona College of Medicine – Phoenix, in a release. “This is the first time this type of lung generation has been accomplished in the world, and it sets the groundwork for new medical advancements and treatments of lung diseases in children and, likely, in adults.”

This study focuses on finding an innovative solution for babies born with chronic lung diseases caused by either prematurity or severe genetic conditions. 

“Pediatric patients who have severe forms of lung disease associated with respiratory failure often need transplantable lung tissues and our study proves generating transplantable lungs from stem cells using large animals as bioreactors is possible. It’s a groundbreaking finding we hope will save lives in the future,” says Kalinichenko in a release.

Prior to this discovery, the bioengineering and embryonic stem cell technology was limited to developing lung tissues consisting of a mixture of donor and recipient cells. These cells, whose origin is a mixture of donor and recipient cells, frequently can be rejected by activation of the recipient’s immune response after lung transplantation. 

The critical differentiating factor with this study is researchers incorporated CRISPR-Cas9, a unique genome editing technology that allows researchers to change genomes by altering sections of the DNA sequence. Modifications of rat embryos by CRISPR-Cas9 allowed the formation of lung tissues consisting of almost all mouse lung cells.

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