3 IgA represents 10–15% of the total ... the typical components of conventional antibodies. This distinct structure was first observed in 1989 during the analysis of both total and fractionated ...

Antibodies to erythrocytes or leukocytes could not be found, but a precipitating antibody reactive with IgA in donor and normal human serum was discovered in the patient's serum. This antibody ...

This finding initiated decades of extensive immunochemical studies of immunoglobulin structure and function ... been used to study the regulation of IgA switching in Warren Strober's laboratory.