Effect of immunotherapy on appearance of antibodies to ragweed in external secretions

Studies on 50 nasal washings, 16 parotid salivas from ragweed-allergic patients, and 10 secretions from normal subjects showed considerable variation in protein and immunoglobulin concentrations. Only 2 immunoglobulins, A and G, were found in nasal washings. Of 26 parotid salivas studied (allergic and controls), IgA was found in 26, IgG in 4, and IgM in 3 specimens. Anti-ragweed antibodies in the serum and exocrine secretions of allergic patients were examined by means of Prausnitz-Küstner (PK) test, radioimmunoelectrophoresis, radioimmunodiffusion, and tanned cell hemagglutination (TH) tests. The incidence of IgE, IgA, and IgG antibodies to ragweed in the sera and nasal washings in a group of 22 patients with previous immunotherapy was compared to that of 28 patients without immunotherapy. The immunotherapy seemed to affect the incidence of serum IgE and IgG antibodies but has no influence on the incidence of anti-ragweed antibodies in the nasal washings. PK activity of nasal washings could be removed by absorption with anti-IgE but not anti-IgA or anti-IgG immunosorbents. Anti-ragweed antibodies could be detected in parotid salivas only by the TH test.