Three-component cancer vaccines

ATHENS, Ga.—In developing vaccines against various cancers, researchers would like to take advantage of the aberrant saccharide or glycopeptides signatures of tumor cells. Unfortunately, because these sugars are self-antigens, they elicit poor B-cell responses that are easily swamped by the body's reaction to the carbohydrate carrier proteins like BSA. Recently, researchers at the University of Georgia developed a tripartite vaccine that overcomes these problems.

As they describe in Nature Chemical Biology, the researchers synthesized vaccine candidates comprised of tumor-associated carbohydrate B epitopes, promiscuous peptide T-helper (Th) epitopes, and Toll-like receptor (TLR) ligands. Using microtiter assays and flow cytometry, they noted that immunized mice showed high IgG titers against the sugar (MUC1) but not the Th epitope, suggesting they had solved the carrier-induced immune suppression.

The researchers also noted that the candidates induced strong cytokine responses, facilitating immune cell maturation. Furthermore, the TLR ligands greatly facilitated uptake by antigen-presenting cells (APCs), which assists with antigen processing and full activation.