Fig. 7.

Immune microenvironment modulation unmasks therapeutic benefit of radiotherapy and checkpoint inhibition. Schematical abstract: Radiation provides potent tumor myeloid and APC infiltration and lymphoid stimulation in the tumor draining lymph node, however, the tumor immune microenvironment often remains immunosuppressed or immunologically “cold”. Targeting of the tumor immune microenvironment using CTX/L-NIL reverts the “cold” intratumoral microenvironment, providing an enhanced myeloid and lymphoid tumor and tdLN microenvironment. Thus, when CTX/L-NIL is combined with radiation and αPD-1/αCTLA-4 inhibition it allows potent immunologic rejection of established tumors and the development of tumor-antigen specific memory