Pulmonary Fibrosis (PF) is a term that describes debilitating lung disease characterized by a progressive decline in lung function. It occurs due to damage and scarring to lung tissues especially around the small air sacs (alveoli). The function of alveoli present in lung tissue is to exchange of oxygen and carbon dioxide to and from the lungs and the bloodstream. You can compare alveoli with home air filter. When air filter is clogged, air handler need to work harder to compensate for the blockage of air flow. Similarly in a person with pulmonary fibrosis, the scar tissue builds up around the alveoli, making it difficult for oxygen to pass from the lungs to the body and breathing becomes a difficult task. PF usually affects people over the age of 50 years and is slightly more common in men than women.
The very first symptom of pulmonary fibrosis is getting out of breath during climbing a hill or stairs and even sometimes during walk. Many people ignore their shortness of breath and link it with getting old. But with time, a small task such as walking or getting dressed can also cause breathlessness.
A persistent dry cough and tiredness are other two common symptoms of pulmonary fibrosis. People suffering with pulmonary fibrosis also have weight loss, fever etc. The disease also affects your fingers and toes. The nails become so soft and finger tips get swollen. The severity of symptoms varies from person to person. Some people will have rapid worsening of symptoms and others have moderate symptoms that worsen slowly over months.
The scarring associated with pulmonary fibrosis can be caused by a multitude of factors, which include following
Environmental factors: The long term exposure to pollutants and allergens can cause damage to lungs. The pollutants can be silica dust, asbestos fibres, coal dust, grain dust, bird feather etc.
Radiation treatment: Sometime, people who have received radiation therapy for cancer treatment, exhibit sign of lung damage in later stages of their life.
Medications: There are some of the drugs which can cause damage to lungs such as certain chemotherapy drugs, heart medications, antibiotics.
Medical conditions: Lung damage can also result from a number of conditions like dermatomyocytosis, polymyositis, rheumatoid arthritis, pneumonia etc.
The lung damage caused by pulmonary fibrosis can’t be repaired. Current available medications and therapies help to ease symptoms, slow down progression of disease and improve quality of life. The oxygen therapy and pulmonary rehabilitation therapy improve endurance and make breathing and exercise easier. Medications such as pirfenidone and nintedanib slow down the progression of fibrosis but have side effects such as rash, nausea and diarrhea.
The lack of curative treatments for this disease has created urgency for other potential therapeutic options. The advancements in stem cell technology have opened up new avenues for treatment of degenerative diseases including lung diseases. Stem cells are the building blocks of every other cells of body. Stem cells are different in that they have the potential to develop and specialize into multiple different types of cells including neurons, heart cells etc. Stem cells have anti-inflammatory and anti- fibrotic properties also, making them more attractive as potential treatment for fibrotic diseases. The stem cell therapy for pulmonary fibrosis focuses on the destroyed lining of the alveoli that is at the root of the issue.
Let us look into on research published with stem cell as a treatment modality for lung recently a clinical trial studied the safety of endobronchial infusions of autologous adipose derived stromal cells (0.5 million cells per kg of body weight per infusion) in patients with pulmonary fibrosis (n=14) of mild to moderate disease severity. No cases of serious or adverse events including short-term infusional toxicities as well as long-term ectopic tissue formation were recorded in all patients. All patients showed not only acceptable safety outcomes, but also improvements in quality of life parameters.
Another clinical study showed the efficacy of placenta derived mesenchymal stem cells in patients with idiopathic pulmonary fibrosis. The patients received dose of placental derived stem cells either 1 × 106 (n = 4) or 2 × 106 (n = 4) MSC/kg via a peripheral vein and were followed for 6 months. Both dose schedules were well tolerated with only minor and transient acute adverse effects. There was no evidence of worsening fibrosis observed.
Clinical studies with large number of patients are needed to strengthen the stem cell therapy approach. However positive overwhelming findings accelerate the rapidly expanded scientific knowledge and indicate a way towards future stem cell therapeutic modality for pulmonary fibrosis.