Dr Michael E. Weschler: The Role of Eosinophils in Health and Disease

Michael E. Wechsler, MD, a pulmonologist at National Jewish Health and director of the Cohen Family Asthma Institute, explains the role that eosinophils play in everyday health and disease development.

Transcript

What role do eosinophils play in health and different diseases?

So, eosinophils play important roles in both health and disease. In health, they play an important role in terms of an immune response. They play a role in homeostasis. They play a role in terms of growth and development in a variety of different organ systems. In terms of immune function, they play a role in parasite immunity, primarily. That's where we think of them the most, but also their roles in terms of tumor immunity and host protection.

In terms of homeostasis, a play a role in a variety of different tissues, including the lungs, the skin, the airways, and the GI [gastrointestinal] tract. And then, in terms of growth and development, they've actually been shown to play a role in terms of growth and development of mammary glands in particular. So, from those perspectives, eosinophils play an important role in terms of maintaining health.

The issue is that if you have too many eosinophils, they can cause some degree of damage, because eosinophils have a variety of granular proteins that they release, including eosinophilic cationic protein, major basic protein, eosinophil derived neurotoxin, and eosinophilic ascites. And so, if there's specific stimuli by tissue injury, or infections by viruses, or different allergies and those can cause the eosinophils to be activated to release those secretary products. And when eosinophils infiltrate the tissue, then that causes damage to the tissue. We see that in a variety of conditions. Everything from asthma, to sinus disease, to eosinophilic GI disease, inflammatory bowel disease, to other eosinophilic conditions.