Circulating levels of IgG1 and IgG4 anti-IgE antibodies and asthma severity.

In this paper, we have determined the levels of IgG1 and IgG4 anti-IgE in the sera of 66 asthma patients suffering from mild (n = 24), moderate (n = 23), or severe (n = 19) symptoms, and 20 nonatopic, healthy subjects. The study has revealed that although asthma patients have significantly elevated levels of IgG1 and IgG4 anti-IgE antibodies, the concentration of these autoantibodies is not related to the severity of asthma. This conclusion may be related to the known heterogeneity of autoanti-IgE antibodies in terms of their ability to trigger basophil histamine release.