Conjugation of Peptides to Carrier Proteins via Glutaraldehyde

There are three common purposes for conjugation of peptides. The most common is induction of humoral immunity (1). This is the production of antibodies capable of binding to the peptide immunogen. The antibodies are elaborated by plasma cells, which are terminally differentiated B-lymphocytes. However, in order for immunity to be successfully induced in a secondary anamnestic response, the immunogen must also react with T-lymphocytes. Many peptides contain B-cell epitopes, but not T-cell epitopes. (Such molecules are called haptens.) Coupling these molecules to a large carrier protein containing T-cell epitopes allows the induction of a B-cell response to the entire immunogen, including the peptide. New synthetic peptides thus offer promise as vaccines (2).