Targeting the stroma by T cells to limit tumor growth

Solid tumors may modulate their environment and keep stromal cells in an immunosuppressive and tumor-promoting state. Recent findings indicate that targeting not only cancer cells but also nonmalignant stromal cells by T cells is required for the eradication of established tumor. Interestingly, a single adoptive transfer of effector T cells that recognize tumor antigen-loaded stromal cells, but not the cancer cells themselves, causes long-term inhibition of tumor growth associated with T cell-mediated killing of stromal CD11b ⁺/Gr1⁺ myeloid cells. Therefore, targeting tumor stroma by T cells points to an important alternative approach to the effective control of tumor growth, particularly in the absence of direct targeting of cancer cells.