Figure 4
NK cells are crucial for the efficacy of Icon immunotherapy of human tongue cancer in vivo in SCID mice. Human tongue tumour xenografts were generated separately in SCID/CB-17 (a) and SCID/Beige mice (b) by subcutaneous injection of the TCA8113 tumour cells into the right flank of each mouse. After tumour formed, adenoviral vector encoding mouse Icon (AdmIcon) or control vector (AdBlank) were injected intratumourally with 1 × 1010 viral particles (vp) per injection for immunotherapy on the days as indicated below. a: In CB-17 SCID mice, AdmIcon (◯, n = 4) or AdBlank (Δ, n = 3) was injected on days 0, 3, 6, 9, 12, 15, 18, 21. Additional intratumoural injections of AdmIcon were administered in 2 partially responded mice on days 54, 84, 93, 99 and 135. P < 0.001 on days 6 and 9 and < 0.001 on days 12-48 for AdmIcon vs. AdBlank by two-way ANOVA. b: In Beige SCID mice, AdmIcon (◯, n = 5) or AdBlank (Δ, n = 5) was intratumourally injected on days 0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 36 and 42. The control mice were euthanised on day 53 and the Icon-treated mice on day 74. P < 0.01 on day 36 and < 0.001 on days 39-51 by two-way ANOVA for AdmIcon vs. AdBlank.