Methods: Sinonasal tissues and nasal lavage fluids (NLF) from young (18-49), mature (50-64), and older adults (≥65) with NP, and from healthy controls from these same age groups were collected. A murine model of NP using ovalbumin and staphylococcal enterotoxin B treatment in 3 age groups of mice was generated: young (2 months), middle-aged (12 months) and old-aged (20 months). Levels of B cell activating factor (BAFF) and anti-dsDNA antibody were measured by ELISA and expression of a plasma cell marker, CD138, examined using immunohistochemistry.
Results: In NP subjects, there was a trend for increased BAFF protein levels in NLF in young (18-49) and mature adults (50-64) with NP compared to healthy controls. Levels of anti-dsDNA antibody were significantly increased in older (≥65) subjects with NP compared to healthy controls (7.9 vs 68.8 IU/ml, p=0.003). Furthermore, mature adults (50-64) with NP showed greater CD138 expression than other two groups. In the murine model of NP, BAFF protein levels were significantly increased in NLF compared to controls in the middle-aged (12 months) NP group (29.4 vs 299.2 pg/ml, p=0.007). Enhanced B cell activation in NP showed a similar age-related pattern between human subjects and the murine model of NP.
Conclusions: This study of human NP and a murine model of NP demonstrates age-related differences in B-cell inflammatory responses in NP.