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.
