Differentiation between control subjects and patients with chronic spontaneous urticaria based on the ability of anti-IgE autoantibodies (AAbs) to induce FcεRI crosslinking, as compared to anti-FcεRIα AAbs

Abstract Background The reported prevalences of IgG autoantibodies (AAbs) to FceRIα and IgE in sera from patients with chronic spontaneous urticaria (CSU) have varied, and these AAbs are also often observed in healthy control subjects. Regarding the histamine release activity of purified IgG from patients with CSU, the number of examined patients has been small. Thus, we sought to determine the prevalence and FceRI crosslinking ability of these AAbs in a large number of patients with CSU and non-atopic control (NC) subjects. Methods We compared the concentrations of anti-IgE and anti-FceRIα AAbs and the abilities of these AAbs to cause FceRI aggregation in patients with CSU (n = 134) and NC subjects (n = 55) using ELISA and an in vitro elicitation test, respectively. Results The concentration of anti-IgE AAbs was significantly different between the NC subjects and the CSU patients ( P P  = 0.0106). Conclusions In the Japanese population of CSU patients studied, the ability of the anti-IgE AAbs to induce FceRI crosslinking differed significantly between NC subjects and CSU patients, suggesting the involvement of anti-IgE AAbs in the pathogenesis of CSU in the Japanese population.