BMP-2 and IL-1β as Markers of Nasal Mucosa Inflammation in Rhinosinusitis with Nasal Polyps

Rhinosinusitis with nasal polyps is characterized by chronic inflammation and hyperplasia of the nasal mucosa. The key mechanism for polyp formation is the expression of molecules that regulate proliferation and inflammation. We studied immunolocalization of bone morphogenetic protein-2 (BMP-2) and IL-1 beta in the nasal mucosa in patients aged 35-70 years (n=70, mean age 57.4 +/- 1.52 years). The typology of polyps was determined depending on the distribution of inflammatory cells, subepithelial edema, the presence of fibrosis and cysts. The immunolocalization of BMP-2 and IL-1 beta had the same pattern in edematous, fibrous, and eosinophilic (allergic) polyps. Goblet and connective tissue cells, microvessels and terminal sections of the glands were positively stained. BMP-2(+) and IL-1 beta(+) cells predominated in polyps of the eosinophilic type. BMP-2/IL-1 beta can be considered as a specific marker of inflammatory remodeling of the nasal mucosa in refractory rhinosinusitis with nasal polyps.