MYELOPEROXIDASE AND INTERLEUKIN-8 LEVELS IN CHRONIC SINUSITIS

We have recently phenotyped inflammation in non-infectious allergic an d nan-allergic chronic maxillary sinusitis using sinus biopsies and la vage fluids. In this first paper, we have concentrated our work on the eosinophil. T cell, mast cell and macrophage infiltrates. However, ma ny unresolved questions remain and particularly the role of neutrophil s needed to be addressed. In the present study. we focused on the neut rophilic inflammation: myeloperoxidase (MPO) and interleukin-8 (IL-8) were measured by immunoassays and neutrophils were enumerated by conve ntional staining in the sinus lavage fluids of 16 patients with chroni c sinusitis and six control subjects. Both MPO and IL-8 levels were si gnificantly higher in patients than in controls (P < 0.01 and 0.005, r espectively). There was a significant correlation between MPO levels a nd neutrophil numbers. and between MPO and IL-8 levels in the sinus la vage fluid (P < 0.0001, Spearman rank correlation). The presence of hi gh levels of IL-8 in the lavage fluids of patients suffering from chro nic sinusitis. levels which correlate with those of MPO. suggests that this cytokine may activate neutrophils in this chronic disease.