Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease that causes obstructed airflow from the lungs. People with COPD are at increased risk of developing heart disease, lung cancer and a variety of other conditions. Emphysema and chronic bronchitis are the two most common conditions that contribute to COPD.Chronic bronchitis is inflammation of the lining of the bronchial tubes, which carry air to and from the air sacs (alveoli) of the lungs.Lung Bronchial lining cells from Bronchial tube appears to be in groups or in sheets with rectangular smears with a smudged nucleus at the base. The elongated rectangular cell with the cilia at the end (indicated by the red arrow) is a bronchial lining cell.