Quantitation and immunocytological identification of interleukin-1 in nasal polyps from patients with chronic...

Immunoreactive interleukin-1 (IL-1) alpha and beta levels in nasal polyp (NP) extracts were measured from 22 adult patients with chronic sinusitis (CS) in order to determine their significance in the pathogenesis of NP. The NP sample was separated into mononuclear and polymorphonuclear fractions. In the mononuclear fraction, the mean value of IL-1 beta was 21.5 pg/ml/g, which was significantly higher than that of IL-1 alpha (8.4 pg/ml/g, p < 0.01). In younger adults, the IL-1 alpha and IL-1 beta levels were 21.2 and 59.4 pg/ml/g, which were significantly higher than those in older CS patients (p < 0.01). There was a significant reverse correlation between patient's age and IL-1 beta levels in the mononuclear fraction (r = -0.509, p < 0.01). Immunoreactive IL-1, mainly IL-1 beta, was identified in the cytoplasmic area of monocytes. A certain amount of immunoreactive IL-1 is produced in mononuclear leukocytes, particularly activated monocytes, and IL-1 beta production is greater than IL-1 alpha. In younger adult CS patients, NPs contain larger amounts of IL-1 beta in monocytes, compared to those of older patients.