Researchers Trying to Zero In on Nasal Polyps Find Target Elusive

This translates into some very unhappy patients. I think we really need new strategies to treat those especially severe patients, Dr. Bachert said.

Anti-IL-5 medications will sort of shoot down your eosinophils, so to speak, he said.

Anti-IgE treatment is another option, but might be difficult to use, because the IgE in patients’ serum can be 200 units, but in local regions can be 1500 units. It might be very tricky to get this IgE antagonized, he said.

Research by Dr. Bachert’s group has shown that the oral steroid methylprednisolone reduces polyp size for a time, but begins to lose its effect on size and airflow after about 40 days. The antibiotic doxycycline has longer lasting effects, of about 80 days, their work has shown.

There might be an approach to at least temporarily suppress staphylococcus and get some benefit for the patient, Dr. Bachert said. Actually, in our clinical practice today, we like to combine steroids and doxycycline, which makes the steroid activity much better and longer.

Gene Expression Profiles

De-Yun Wang, MD, PhD, Associate Professor of Otolaryngology at the National University of Singapore, recently walked the same Rhinology World audience through abnormalities of the gene expression profiles in nasal polyps, including his research group’s findings of the importance of the AP-1 transcription factor.

Examination of the cells in nasal polyps shows mucosal inflammation and epithelial damage, with IL-5 and eotaxin and other eosinophil activators present.

The epithelium hyperplasia of basal cells, as well as squamous and goblet cells, is a stark contrast to the neat layers of basal cells, ciliated columnar cells, and interspersed goblet cells seen in normal nasal epithelium.

Testing of Asian patients has shown that allergies probably do not play a key role in the actual formation of nasal polyps, at least in that population, with atopy in 29.7% of patients with the lesions. The percentage of patients with atopy is quite small, Dr. Wang said. This is even lower than atopy in the general population. So we definitely can see that allergy probably doesn’t play a very important role.

Inflammation in polyps seems to involve eosinophils more than neutrophils, according to analyses of cell patterns. Eosinophils were seen alone in 21% of the patterns viewed, and seen with other cell types in another 42%. Neutrophils were seen alone in only 10% of the patterns viewed, but were seen in another 40% with other cell types, Dr. Wang said.