Stem cell therapy for lung fibrosis is a ray of hope

I was quite fascinated when the other day I read a news report by “Team Herald” entitled, “Stem Cell Therapy for Lung Fibrosis Developed”. I decided to dig deeper and after going through a lot of sources - with whatever I learnt - I wish to acquaint my readers about the details of this disease (luckily uncommon} and the advances that are being made to treat an otherwise intractable illness. Idiopathic Pulmonary fibrosis (IPF) is one of a family of related diseases called “interstitial lung diseases” that can result in lung scarring interfering with a person's ability to breathe. “Idiopathic” denotes that the disease arises spontaneously and the cause is unknown. 

Our lungs are a pair of spongy, air-filled organs located on either side of the chest (thorax). The trachea (windpipe) conducts inhaled air into the lungs through its tubular branches, called bronchi. The bronchi then divide into smaller and smaller branches (bronchioles), finally becoming microscopic. Pulmonary alveoli are any of the small air spaces in the lungs where carbon dioxide leaves the blood and oxygen enters. “Oxygen-laden-air” entering the lungs during inhalation, travels through bronchi and then flows into approximately 300 million alveoli and crossing a tiny barrier (interstitium) is delivered into the blood-stream. During exhalation, it is the reverse: “the carbon-dioxide-laden air” is forced out of the alveoli through the same passageways. 

Pulmonary fibrosis is a disease that scars the lungs, causing the intricate “interstitium” to thicken and harden obstructing the free passage of oxygen through the walls of these alveoli into the bloodstream. The resulting lack of oxygen in the bloodstream leaves pulmonary fibrosis sufferers short of breath even after periods of prolonged rest. IPF is a progressive disease that varies in the rate of deterioration from person to person. Typically, sufferers of pulmonary fibrosis do not live more than 5 years after a diagnosis. It has no specific demographic pattern but it does affect men more than women and typically occurs in individuals between the age of 50 and 70. 

How do we diagnose the condition? “High-Resolution Computed Tomography” (HRCT scan) is one of the most helpful tests to diagnose IPF. HRCT scan is an x-ray that provides sharper and more detailed pictures than a “standard chest X Ray.” It can show scar tissue and how much lung damage you have. This test can help your doctor spot IPF at an early stage or rule it out. But it is “lung biopsy” that is the ultimate test to clinch the diagnosis. Your doctor will take samples of lung tissue from several places in your lungs. The samples are examined under a microscope. Doctors use several procedures to get lung tissue samples: a) video-assisted-thoracoscopy b) bronchoscopy c) thoracotomy, where your doctor removes a few small pieces of lung tissue through a cut in the chest wall between your ribs. Thoracotomy is done in a hospital. You'll be given medicine to make you sleep during the procedure.

There is no satisfactory treatment for IPF but, as pointed above, stem cell therapy has brought in a ray of hope. Stem cells are immature cells that can proliferate and turn into adult cells in order to, for example, repair injuries. Some types of stem cells have anti-inflammatory and anti-fibrosis properties that make them particularly attractive as potential treatments for fibrotic diseases. 

Cheng and Lobo from the UNC School of Medicine and North Carolina State University (NCSU) have focused on a set of stem cells and support cells that reside in the lungs and can be reliably cultured from biopsied lung tissue. The cells are called “lung spheroid cells” for the distinctive sphere-like structures they form in culture. The researchers showed that they could obtain lung spheroid cells from human lung disease patients with a relatively non-invasive procedure called a transbronchial biopsy. “We snip tiny, seed-sized samples of airway tissue using a bronchoscope,” Lobo said. “This method involves far less risk to the patient than does a standard, chest-penetrating surgical biopsy of lung tissue.”

Cheng and Lobo cultured lung spheroid cells from these tiny tissue samples until they were numerous enough – in the tens of millions – to be delivered therapeutically. When they infused the cells intravenously they found that most of the cells gathered in the lungs. “These cells are from the lung, and so in a sense they’re happiest, so to speak, living and working in the lung,” Cheng said.  He also avers that the treatment is safe and effective. 

To obtain enough cells for widespread clinical use, doctors might harvest them from healthy volunteers, as well as from whole lungs obtained from organ donation networks. The stem cells could later be used in patients “as-is” or matched immunologically to recipients in much the same way transplanted organs are typically matched. “Our vision is that we will eventually set up a universal cell donor bank,” Cheng said.

Without a doubt, stem cell research is expected to lead to the dramatic improvement of various human conditions and will benefit millions of people. Medical scientists too have never lagged behind in doing their best to ameliorate the predicament of the suffering humanity. 

Yet, as Hippocrates wrote years ago, “The life so short, the craft so long to learn.”

(Dr. Francisco Colaço is a seniormost consulting physician, pioneer of Echocardiography in Goa, column writer, singer/songwriter/music aficionado, Mando exponent, past president of the state IMA, social activist, popular orator and toastmaster, family man, with deep faith in God.)