Redirecting immunity via covalently incorporated immunogenic sialic acid on the tumor cell surface

Techniques eliciting anti-tumor immunity are of interest for immunotherapy. We herein report the covalent incorporation of a non-self immunogen into the tumor glycocalyx by metabolic oligosaccharide engineering with 2,4-dinitrophenylated sialic acid ((DNP)Sia). This enables marked suppression of pulmonary metastasis and subcutaneous tumor growth of B16F10 melanoma cells in mice preimmunized to produce anti-DNP antibodies. Located on the exterior glycocalyx, (DNP)Sia is well-positioned to recruit antibodies. Given the high levels of natural anti-DNP antibodies in humans and ubiquitous sialylation across many cancers, (DNP)Sia offers a simplified route to redirect immunity against diverse tumors without recourse to preimmunization.