A new type of pulmonary stem cell has been identified by scientists at UCLA. These cells have a potential to regenerate large damaged airways and play an important role in strengthening immunity against infectious agents and environmental toxins.

Mucous secretion and clearing by the airways is a protective mechanism against pathogens and environmental toxins. Mucus is secreted by special types of glands in the airways, but the mechanisms regulating the amount of secretion are not completely understood. The discovery of these novel pulmonary stem cells is believed to provide more information about these obscure mechanisms.

Researchers during a study at the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA have made a landmark discovery in finding the progenitor cell which forms the mucus gland and can repair lung epithelial linings. The innovators claim that the discovery of this stem cell is of major importance to the field of lung regeneration.

Dr. Brigitte Gomperts, an assistant professor of pediatrics and hematology/oncology and senior author of the research study expresses his optimism about the usefulness of this type of stem cell in further understanding the mechanisms of pulmonary diseases. Citing examples regarding the application of these stem cells, he states that there are currently no treatments for the excess mucous production in conditions like asthma, chronic obstructive pulmonary disease (COPD) and cystic fibrosis. He further states that by understanding the mechanisms of regeneration due to these stem cells we may be able to control the excessive mucus production.

The study will be published in peer-reviewed journal ‘Stem Cells’ on the 27th of June 2011.

The newly discovered pulmonary stem cells have been named ‘sub-mucosal gland duct stem cells’ by Ahmed Hegab, a postdoctoral scholar in Gomperts lab and first author of the study. They have been so named because they are found in the ducts where mucus is first secreted. Hegab and Gomperts have been researching pulmonary stem cells for years, and created a model of regeneration of the airways to identify and locate the stem cells.

Gomperts and her team first proved that pulmonary stem cells existed and found their location. They further experimented to isolate them and confirmed that they could multiply and differentiate into cells forming the mucus glands and bronchial epithelium.

Models were constructed in which these stem cells could make mucus glands with all the constituent cell types present to produce mucus, and repair the lining epithelium of the larger airways.

This research study claims that the identification of these stem cells with regenerative potential is a step forward towards identification of novel therapeutic targets for pulmonary disease and promising cell-based therapies in the future.

Gomperts, who is also a member of UCLA’s Jonsson Comprehensive Cancer Center, expresses concern that the repair process can go berserk and form cancer, although further research is required to confirm this.

This study was sponsored by the California Institute of Regenerative Medicine, American Thoracic Society/COPD Foundation, the Concern Foundation, UCLA’s Jonsson Comprehensive Cancer Center’s Thoracic Oncology Program and Specialized Program of Research Excellence in lung cancer, the University of California Cancer Research Coordinating Committee and the Gwynne Hazen Cherry Memorial Laboratories.

Written by Barry Windsor