P28z T cell persistence and anti-tumor effect against rechallenged tumor. (a) Schema of in vivo tumor rechallenge model. (b) Graph indicates tumor volume of primary tumor (gray back ground) and rechallenged tumor (light green background). The arrow indicates the time of tumor rechallenge. (c) Representative mice images with T cell bioluminescence on the day of tumor rechallenge (day 42 post T cell injection). Graph summarizes the result of bioluminescence from individual mice (mean ± S.E., n = 4–6). (d) Representative mice image showing T cell bioluminescence at different time points. (e) Bar graph summarizes T cell bioluminescence at rechallenged tumor site on day 7 post tumor rechallenge from individual mouse and line graph shows T cell bioluminescence at rechallenged tumor site over time (mean ± S.E., n = 4–6). Statistical differences are calculated by One-way ANOVA with Tukey multiple comparison (c, e). *p ≤ 0.05, **p ≤ 0.01.