Measurement of specific IgA antibodies against Aspergillus fumigatus is used in the diagnosis of allergic bronchopulmonary aspergillosis.
All sera from patients with allergic bronchopulmonary aspergillosis (ABPA) have high levels of specific IgA antibodies against Aspergillus compared to sera from non-affected subjects. All patients with ABPA have been shown to have high levels of specific IgA antibodies in acute, recurrent, and fibrotic stages of the disease. Because the main stimulus for the production of specific IgA antibodies occurs in the lungs as a result of the presence of fungal tissues, these antibodies may be involved in the immunological destruction of the lungs in patients with ABPA.
See also: Aspergillus fumigatus, IgG Antibodies & Aspergillus fumigatus, IgM antibodies