CD4 and neoplasm: Given the existence of remarkable similarities between ILC2s and CD4+ T helper lymphocytes, we hypothesized that the adoptive transfer of tILC2s could reduce the growth of tumors and demonstrated, for the first time, the direct involvement of tILC2s in immunologically limiting tumor growth through the recruitment of key immune players including CD4+, CD8+ T cells, and eosinophils.