Kinetics of Immunoglobulins in Nasal Secretions of Chronic Sinusitis and Nasal Allergy

Abstract

Chronic sinusitis is still one of the most prevalent nasal illnesses in Japan. The pathogenesis of this disease has not been fully understood yet. It has been shown that most of the IgA antibody secreted from the normal respiratory mucosa appeared to be of 11 S-IgA type. However, when the condition is inflammatory, change in the normal epithelial-capillary barrier results in a marked influx of serum immunoglobulins and other proteins, so that the kinetics of immunoglobulin classes in the external secretions changes remarkably and becomes more complicated.In the present study, we measured the concentration of immunoglobulins and other proteins in the nasal secretions from chronic sinusitis and nasal allergy, which represent the chronic nasal diseases of infectious and allergic inflammation, respectively. In the nasal allergy, the mean concentration of immunoglobulins was very similar to that of the previously-reported normal subjects. The mean concentrations of IgA, IgG, IgM and S-IgA in chronic sinusitis were significantly different from those in nasal allergy and the mean concentration of S-IgA in chronic sinusitis was almost three times as high as in nasal allergy. Comparing the concentration ratios of IgA/IgG and IgA/albumin with the normal in the serum, it was found that there was high local production of IgA in both diseases. However, the mean concentration of S-IgA and mean concentration ratio of S-IgA/total IgA in purulent secretion were not significantly different from the mucous secretion of chronic sinusitis and they varied considerably. In one-third of purulent secretions, the S-IgA/total IgA ratios were very low. α1-antitrypsin which is the main protease inhibitor in the serum had a significant correlation with the concentrations of DNA and IgG, but not with S-IgA. S-IgA was measured by the enzyme-linked immunosorbent assay and electroimmunodiffusion with the enzyme -labeled antibody method.In conclusion, it was found that there were different immunoglobulin kinetics in the noses of patients with chronic sinusitis and nasal allergy and immunoglobulin concentrations were different between purulent and mucous secretions of chronic sinusitis. Although the bulk of IgA and IgG was derived from serum, it was suggested that local synthesis of IgA and IgG was active in the nasal mucosa of chronic sinusitis.