Table I.

Summary of pre-clinical studies evaluating the effects of ionizing radiation on T-lymphocyte function within the tumor immune microenvironment.

Title and reference	Authors	Journal	Year	Model	IR	Results	Mechanism
Suppressing T cell motility induced by anti-CTLA-4 monotherapy improves antitumor effects	Ruocco et al	J Clin Invest.	2012	4T1	12Gyx2	Motility arrest of CD8 TIL within tumor after IR	Increased tumor cell ICAM-1 after IR
Anti-PD-1 blockade and stereotactic radiation produce long-term survival in mice with intracranial gliomas	Zeng et al	Int J Radiat Oncol Biol Phys.	2013	GL261	10Gyx1	Increased CD8 TIL infiltration	Increased tumor cell MHC class I, ICAM-1 and CXCL16 expression after IR
Therapeutic effects of ablative radiation on local tumor require CD8+ T cells: changing strategies for cancer treatment	Lee et al	Blood	2009	B16-SIY	20Gyx1 5Gyx4	Tumor control and rejection after single high dose IR but not after fractionated IR	CD8 dependent tumor rejection after IR
Maximizing tumor immunity with fractionated radiation	Schaue et al	Int J Radiat Oncol Biol Phys.	2012	B16-OVA	3Gyx5 5Gyx3 7.5Gyx2 15Gyx1	7.5Gyx2 resulted in better tumor control than other IR regimens	7.5Gyx2 resulted in highest peripheral IFNγ producing cell:Treg ratio
Local radiation therapy of B16 melanoma tumors increases the generation of tumor antigen-specific effector cells that traffic to the tumor	Lugade et al	J Immunol.	2005	B16-OVA	15Gyx1 3Gyx5	Enhanced tumor control with single high dose compared to fractionated IR	Increased IFNγ producing and cytotoxic cells in the tumor of mice treated with 15Gyx1
STING-Dependent Cytosolic DNA Sensing Promotes Radiation-Induced Type I Interferon-Dependent Antitumor Immunity in Immunogenic Tumors	Deng et al.	Immunity	2014	MC38	20Gyx1	Single high dose of IR induces control of established MC38 tumors	Tumor control after single high dose IR abrogated with CD8 cell depletion
Ablative Tumor Radiation Can Change the Tumor Immune Cell Microenvironment to Induce Durable Complete Remissions	Filatenkov et al.	Clin Cancer Res.	2015	CT26 MC38	30Gyx1 3Gyx10	Rejection of established CT26 and MC38 tumors after single high dose IR but not after fractionated IR	Tumor rejection after single high dose IR abrogated with CD8 cell depletion