Figure 7.

TCR CD8⁺ T cm Monotherapy Leads to Tumor Relapse in Target ML2B7 Tumors in NSG Mice

ML2B7 tumor-bearing NSG mice were treated 10 days after tumor implantation by tail-vein injection and were euthanized at humane endpoints due to poor health or when the tumors reached a diameter of 2 cm. (A) Survival times were plotted by Kaplan-Meier curve (n = 5–6). Long-term surviving TCR T cell-treated mice with relapsing tumors were administered a second round of treatment on day 52 after initial therapy as indicated. ***p < 0.0001 by log-rank [Mantel-Cox] test. (B) Tumor sizes of individual mice treated with TCR T cells were plotted until the time of euthanasia. The dotted line indicates the time point of the second treatment with TCR T cells. (C) Relapsed tumors were analyzed by flow cytometry to determine presence of the targeted HLA, using the co-expressed GFP as a surrogate marker. Representative FACS dot plots of control tumor that expressed the HLA (left) and a relapsed tumor lacking GFP expression (right) are shown.