In contrast, tumor-reactive CD4+ TILs were primarily represented by the CD137- Antitumor function+ (average 69%) and CD137+ Antitumor function+ (average 26%) populations (Figure 2F), indicating that CD137 is critical for identifying the CD8+ but not the CD4+ reactive TIL repertoire. Here, TNFRSF9 is linked to neoplasm.