SPECIFIC ANTIBODY DETECTION IN INVASIVE ASPERGILLOSIS BY ANALYTICAL ISOELECTROFOCUSING AND IMMUNOBLOTTING METHODS

Aspergillus fumigatus antigens have been tested to determine their pot ential as aids in the diagnosis of invasive aspergillosis (IA). Immuno globulin G (IgG) antibodies to these antigens were detected by analyti cal isoelectrofocusing in conjunction with immunoblotting. A total of 12 antigenic fractions, including culture filtrates and surface and my celial extracts of A. fumigatus, were investigated. Eleven were reacti ve with serum specimens from patients with aspergilloma, which served as positive controls for the evaluation of a specific IgG response. Ei ght of 12 antigens showed goad responses with serum specimens from pat ients with allergic bronchopulmonary aspergillosis, which were used to assess the sensitivity of IgG detection. No measurable reactivity was detected in 18 negative control serum specimens, while 11 of 13 patie nts with proven, highly probable, or probable cases of IA had anti-Asp ergillus IgG to multiple antigenic preparations. Patients with IA who were capable of mounting a substantial humoral response to Aspergillus antigens gave an antibody profile with five antigenic preparations wh ich seemed to be characteristic of the disease. Data show that this me thod is highly sensitive and may allow the selection of fractions whic h are both highly antigenic and specific for the detection of antibodi es to Aspergillus antigens. They also indicate that the use of a spect rum of antigenic molecules is advisable, given the variability observe d in the immune responses of individual patients.