The immunological identity of tumor: Self implications

Abstract

By means of well-characterized autoimmunity models, we comparatively probed the "selfness" of malignant cells and their normal counterparts. We found that tumors activate self-tolerance mechanisms much more efficiently than normal tissues, reflecting a status of immunoprivileged "self." Our findings indicate that potent autoimmune responses can eradicate established malignancies, yet the collateral destruction of healthy tissues may prove difficult to circumvent.

Keywords: altered self; autoimmunity; cancer; immunoprivileged self; regulatory T cell (Treg).

Figure 1. Tumor as an “altered self” or “immunoprivileged self” entity. The hypothesis that self epitopes are abundant in the antigenic repertoire of tumor cells is based on the facts that tumor-specific antigens (TSAs) are difficult to identify and that antitumor immune responses often target self antigens. Blue dashes depict the immunosuppressive microenvironment that is often associated with tumors. Oval areas reflect overall tumor burdens and do not necessarily represent individual tumor sites. Ab, antibody; TIC, tumor-initiating cell.