Th1 and Th2 cytokine gene expression in atopic and nonatopic patients with nasal polyposis.

The pathogenesis of nasal polyps has been debated for many years. The lymphocytes that infiltrate nasal polyps have been identified as predominantly memory T cells in an activated state, and these cells produce a mixed cytokine pattern of T1 helper (Th1) and T2 helper (Th2) cells. We conducted a prospective study to compare the expression levels of some Th1 and Th2 cytokines in atopic and nonatopic patients. Our study population consisted of 75 adults-42 men and 33 women (mean age: 38 yr)-with nasal polyposis. Patients with an allergy were distinguished from those without an allergy on the basis of the history, the results of skin-prick testing, and measurement of total IgE serum concentrations. Based on these criteria, patients were divided into two groups: atopic (n = 38) and nonatopic (n = 37). Levels of cytokine gene expression in the atopic patients were compared with those of the nonatopic patients by real-time polymerase chain reaction. Statistical analysis found no significant differences in the rate of interleukin (IL) 10 and IL-12 gene expression between the allergic and nonallergic patients. On the other hand, rates of interferon gamma and IL-4 gene expression were significantly higher in the atopic patients (p = 0.03 and p = 0.02, respectively). Our research suggests that an imbalance of Th1 and Th2 cells plays an important role in the pathophysiology of nasal polyps. Although nasal polyposis is a multifactorial disease associated with several different etiologic factors, chronic persistent inflammation is undoubtedly a major factor, regardless of the specific etiology.