L-rhamnose antigen: a promising alternative to α-gal for cancer immunotherapies

The targeting of autologous vaccines toward antigen presenting cells (APCs) via the in vivo complexation between anti α-Gal (anti-Gal) Antibodies and α-Gal antigens presents a promising Cancer Immunotherapy with enhanced immunogenicity. This strategy takes advantage of the ubiquitous anti-Gal antibody in human serum. In contrast to the α-Gal epitope, the recent identification of high titers of anti-l-rhamnose (anti-Rha) Antibodies in humans reveals a new approach toward immunotherapy employing l-rhamnose (Rha) Monosaccharides. In order to evaluate this simple antigen in preclinical applications, we have synthesized Rha-conjugated immunogens and successfully induced high titers of anti-Rha Antibodies in wildtype mice. Moreover, our studies demonstrate for the first time that wildtype mice could replace α1,3galactosyltransferase knockout (α1,3GT KO) mice in such antigen/antibody-mediated vaccine design when developing Cancer immunotherapies.