Strikingly, tumor growth remained fully controlled by CDNP-R848, even in the absence of CD4+ and CD8+ T cells and—unlike in subcutaneous tumor models9—tumor growth was unchanged compared to isotype controls (tumor volume week 4: CDNP-R848 + α-CD8: 3.9 mm3 vs CDNP-R848 + isotype: 3.6 mm3, n.s.; tumor volume CDNP + α-CD4 depletion: 39.03 mm3 vs CDNP-R848 + α-CD4: 1.4 mm3, p < 0.001, vs CDNP-R848 + isotype: 1.0 mm3, n.s., n = 5–7 animals per group, Fig. 4a, b, d, Supplementary Fig. 5b, c, e, f). Here, CD4 is linked to neoplasm.