Molecular Heterogeneity of Secretory IgA Anti-DNP Antibodies¹

Evidence is presented that demonstrates that the microscale sucrose isoelectric focusing technique can be used to assess the molecular heterogeneity of secretory IgA anti-DNP antibodies. The data indicate that substitution of the DNP group on the bacterial carrier, pneumococcus, can limit the structural complexity of secretory IgA anti-DNP antibodies. The data support the concept that factors governing secretory IgA antibody heterogeneity are analogous to those influencing the heterogeneity of serum IgG antibodies.