IL4 and neoplasm: To determine whether the potent anti-tumor effects observed when combining the 2G CAR with 4/7ICR would be recapitulated in vivo, NSG mice were engrafted (s.c. in the left inferior mammary fat pad) with 5 × 106 IL4-producing MDA MB 468 cells (MDA MB 468/IL4) (Fig. 4a).