Secretory antibodies in IgA-deficient and immunosuppressed individuals

Abstract

Total levels of IgM and secretory IgM as well as specific antibodies to poliovirus type I antigen,Escherichia coli O antigens, and β-lactoglobulin were measured in unstimulated and stimulated saliva as well as nasal secretion using an enzyme-linked immunosorbent assay (ELISA). The levels of these antibodies in IgA-deficient adults with and without frequent respiratory infections and children under immunosuppressive therapy for malignant disease were compared to those in normal adults and infants 1–7 months of age. The IgA-deficient adults had significantly higher IgM levels (PPE. coli O antigen (PPPE. coli O antigens and poliovirus type I antigen in saliva from children treated with multiple cytotoxic drugs for malignant disease did not differ from normal levels, irrespective of the duration of treatment. The lower IgM levels in saliva of IgA-deficient individuals with many infections was seen in spite of their frequent infections, suggesting a primary defect in an important compensatory defense mechanism.