Breathe Easy: New Lung Stem Cell Therapy May Lead to New Treatments
Posted on December 1, 2017
Researchers at the Stanford University School of Medicine have identified a specific type of lung stem cell able to develop into two different types of lung tissue. Their findings may spark new treatments for individuals with hard-to-treat lung disease.
The study authors were prompted to take on the project in an attempt to solve a problem that previous lung research could not: successfully treating damaged lungs with new lung stem cells.
The lungs are vital organs and work in partnership with the heart to move oxygen throughout the body. When lungs become damaged by illness, disease or injury, the oxygen becomes restricted, resulting in tissue death, organ dysfunction and health conditions such as congestive heart failure.
Treatments for patients with lung damage include steroids, anti-inflammatory drugs and oxygen therapy, but individuals with severe lung damage may require lung transplant surgery.
A Specialized Cell
Like other tissues of the body, the lungs develop from specific stem cells. The stem cells that grow into the lungs create the two parts of the lungs: the airway and the alveoli.
The airway portion is responsible for taking air in and out of the lungs during respiration. The alveoli are the tiny sacs in which the gas exchange occurs and oxygen converts to carbon dioxide.
To be able to heal tissue in both parts of the lungs successfully, the researchers had to find a lung stem cell that would be able to develop into both airway and alveoli tissue.
The lung stem cell that met their requirements was a multi-potent lung stem cell with a protein marker known as Sox9.
Multi-potent stem cells have the ability to regenerate infinitely and can differentiate into many different types of cells.
After isolating the lung stem cells with the Sox9 protein marker, the researchers then had to multiply the stem cells to have enough to make therapy beneficial.
“Stem cell therapy requires a large number of cells to provide a therapeutic effect and begin healing,” said Dr. Joel Singer, M.D.
Singer is a New York physician who treats patients with lung damage, asthma and chronic obstructive pulmonary disorder using another kind of stem cells: adipose fat stem cells.
The Stanford researchers grew each lung stem cell collected to 100 billion stem cells over a six-month period. This feat was exciting to the researchers on the project because previous attempts to grow lung stem cells to large numbers were unsuccessful.
“Like lung stem cells, adipose fat stem cells are also multi-potent stem cells. The difference between lung stem cells and adipose fat stem cells is that adipose fat stem cells are typically in abundance, while lung stem cells are low in number,” Singer said.
After growing the stem cells, the researchers injected them into mice with lung damage and then watched the lungs for changes. They found that previously existing lung damage was repaired in both lung compartments.
The Growing Need for New Lung Therapies
The need for new therapies to treat people with lung damage is increasing. According to the U.S. Centers for Disease Control and Prevention, 15.7 million Americans are living with COPD.
The CDC also estimates that 50 percent of adults with low pulmonary function have COPD but are undiagnosed. As a result, the number of people living with COPD in the United States may be much higher.
“Stem cell therapy is ideal for some patients with COPD and other types of lung damage because these patients may not respond to treatments like oxygen therapy or may not be able to tolerate other interventions like surgery,” Singer said.
Medical Express. Researchers find lung stem cell, heal lung injury in mice. Medical Express. 15 November 2017.
Centers for Disease Control and Prevention. Chronic Obstructive Pulmonary Disease (COPD). CDC. 2017.