Non-IgE,-IgG4 Antibody to Japanese Cedar Pollen Allergens:Comparison of Its Prevalence and Titers between Pollinosis Patients and Non-Patients

Abstract

Background: IgG antibody to allergens in the serum of pollinosis patients is not routinely measured, because there are no simple methods for assaying small amounts of specific IgG in the serum ; so far only IgE and IgG4 antibodies have been assayed. In this study, we used a reverse-sandwich ELISA for measuring specific non-IgE,-IgG4 (probably, mainly IgG1) to Japanese cedar pollen allergens, and compared the antibody-positive rates and geometric mean antibody titers between pollinosis patients and non-patients (healthy individuals). Methods: Antibodies to two major allergens of Japanese cedar, Cry j 1 and Cry j 2, were assayed by the following methods : specific non-IgE,-IgG4 was measured by a reverse-sandwich ELISA ; specific IgE and IgG4 were measured by indirect ELISAs. Results: We detected specific non-IgE,-IgG4 in both the patients and non-patients. In comparison to the IgE antibody, which was detected in a small proportion of the non-patients with low titers, the non-IgE,-IgG4 antibody was present in a higher proportion with higher titers among both the patients and non-patients. Conclusions: Healthy individuals had specific non-IgE,-IgG4 to Japanese cedar allergens in a higher proportion than the specific IgE. The non-IgE,-IgG4 antibody assay may be useful in studies on the prevalence of allergen-specific antibody responders and may help in clarifying the natural history of pollinosis.

Keywords

• IgG4 antibody in non-patients
• Japanese cedar pollinosis
• non-IgE
• reverse-sandwich ELISA