Immune recognition of serum albumin. 11. Mouse antibodies against bovine serum albumin recognize the same antigenic sites that are recognized by rabbit antibodies.

In recent studies, we have localized and confirmed by synthetic peptides five major antigenic sites in each of bovine and human serum albumins which are recognized by rabbit antibodies against the respective protein. In order to determine whether the antigenic sites of albumin are peculiar to the protein or are dependent on the species of the immunized host, we have studied here the specificity of the antibody response in outbred mice against bovine serum albumin. By immunoadsorbent titration studies, the synthetic antigenic sites, previously localized with rabbit antisera against bovine serum albumin, were shown to bind considerable amounts of specific mouse 125I-labelled antibodies against bovine serum albumin. The amounts of mouse anti-bovine serum albumin antibodies bound by the adsorbents of the synthetic sites were comparable to the amounts of rabbit anti-bovine serum albumin antibodies that could be bound. It was concluded that recognition of the antigenic sites of serum albumin is independent of the immunized species and is inherent in their structural and conformational uniqueness.