Seeding tumors with foreign class I antigens

Antigen Seeding Technology (AST)

ETBs route to the cytosol where they can intersect with the cell’s antigen presentation pathway. In antigen seeding, foreign class I antigens are attached to an ETB.

The ETB routes to the cytosol of the tumor cell where the antigen can be processed and displayed in complex with an MHC class I molecule on the cell surface. Tumor cells expressing the foreign peptide/MHC class I complex on their cell surface can be targeted for destruction by high-avidity cytotoxic T-cells resident in the patient.

CMV Class I Antigens

CMV-specific CD8 T cells retain cytotoxic activity and generally do not express high levels of PD-1 or other exhaustion markers, protecting them from canonical mechanisms of exhaustion.

Reactivation of CMV, for example, rarely occurs in CLL patients despite these patents having a generally exhausted T-cell profile, Most cancer patients have a high reservoir of activated CMV-specific T-cells.