Increased Expression of CD69 Antigen on Human Peripheral Blood Natural Killer Cells in Patients with Allergic Rhinitis

Allergic rhinitis (AR) is an inflammatory disorder of the nasal mucosa with high morbidity and prevalence. Natural killer (NK) cells might have a role in AR. We aimed to evaluate the changes of the markers and receptors on NK cells in AR patients compared to the non-atopic controls. Flow cytometric analysis was used with double staining of the Peripheral Blood Mononuclear Cells (PBMCs) to examine the expression of CD25 and CD69 markers, and NKG2D and NKG2A receptors on NK cells of 20 patients with AR and 20 non-atopic controls. The serum total IgE level was measured by Enzyme-linked Immunosorbent Assay. The expression of CD69 antigen on NK cells in AR patients was significantly higher than that of healthy group (p=0.03). No significant changes were observed between CD25, NKG2D and NKG2A expression on the surface of NK cells from healthy and AR subjects. Our study also showed that there was no significant correlation between the expression of CD69, CD25, NKG2D and NKG2A and level of serum total IgE in AR patients and normal subjects. These results indicated that the expression of CD69 antigen on NK cells of AR patients was increased. The high expression of CD69 on NK cells in AR patients suggested that these cells were activated, probably due to the cytokines secreted from allergen-stimulated T cells and activated monocytes.