CD4 and neoplasm: Lentiviral vectors have been broadly used to generate NK cells expressing CARs with 1st, 2nd and 3rd generation designs which target different tumor antigens including CD19 [122,140], CD20 [140], TF in TNBC [145], CD33 [146], CD7 [147], CD22 [148], ErbB2 [129], EpCAM [141], Glypian-3 (GPC3) [142], CS1 [143], EGFR [127,132], B cell maturation antigen (BCMA) [149] and CD4 [144].