Polyvalent tumor-associated carbohydrate and peptide antigens (TACAs/TAPAs)

Polyvalent tumor-associated carbohydrate and peptide antigens (TACAs/TAPAs) are a group of surface molecules, including gangliosides (GM2, GD2, GD3), neutral carbohydrates (Globo H, Lewis Y), and mucin-related structures (Tn, sTn, MUC1), that are characteristically overexpressed in various malignancies (Ragupathi et al., 2005). These antigens are typically poorly immunogenic because they are "self-antigens"; to overcome this, they are chemically conjugated to Keyhole Limpet Hemocyanin (KLH), a large, highly immunogenic carrier protein (Livingston, 1995). The KLH carrier provides necessary T-cell epitopes that stimulate a robust immune response, leading to the production of high-titer antibodies (IgM and IgG) against the tumor-specific carbohydrate and peptide motifs (Sabbatini et al., 2007). This polyvalent approach is designed to target multiple epitopes simultaneously, thereby addressing the issue of tumor heterogeneity and reducing the likelihood of immune escape by the cancer cells (Gilewski et al., 2001). When administered with an adjuvant such as QS-21, these vaccines aim to induce complement-dependent cytotoxicity and antibody-dependent cellular cytotoxicity against the tumor (Krug et al., 2004). Clinical development has primarily targeted epithelial and neuroectodermal tumors, such as ovarian, breast, prostate, and small cell lung cancers (Ragupathi et al., 2005; Sabbatini et al., 2007).

Other names

Polyvalent tumor-associated carbohydrate/peptide antigens presented on KLHTumor-associated carbohydrate antigens (TACAs)Tumor-associated peptide antigens (TAPAs)Multi-antigen KLH conjugatePolyvalent cancer vaccine antigens

Active immunization inducing a humoral and cellular immune response against multiple tumor-associated antigens, facilitated by T-cell help from the KLH carrier protein.