抄録
Background: There has recently been an accumulation of evidence suggesting that endothelial cells (EC) play a crucial role in the pathogenesis of bronchial asthma. We examined the prevalence and isotypes of anti-EC antibodies (AECA) in the sera of children with asthma and determined the antigenic targets associated with AECA reactivity.
Methods: Levels of each class of AECA were determined by cellular ELISA in 156 children with asthma and in 203 control children. Sodium dodecyl sulfate- polyacrylamide gel electrophoresis and western blot analysis were performed in samples that contained high levels of AECA.
Results: In the cellular ELISA, the IgE class of AECA was detected significantly more frequently in children with asthma (25/156; 16.0%) than in healthy controls (2/203; 1.0%; P > 0.01). There were no differences in the frequencies of detection of IgG, IgA and IgM classes of AECA between patients and controls. The IgE-AECA was more frequently detected in younger children (23/69 vs 2/87 for children younger and older than 4 years of age, respectively). There was no correlation between the level of IgE-AECA and that of total IgE or house dust mite-specific IgE. In western blot analysis, IgE antibodies against a component of EC with a molecular mass of 75 kDa were detected in 20 of 25 patients (80.0%) positive for IgE-AECA, but they were less frequently detected in patients negative for IgE-AECA (2/34 (5.9%); P < 0.01).
Conclusions: These results demonstrate that a small fraction of asthmatic children has IgE-AECA and that the antigenic target of IgE-AECA is a component of the EC with a molecular weight of 75 kDa.
