CD8A and neoplasm: In a comprehensive study, Turtle et al., have demonstrated that cell product composition [CD8+ Tcm vs. bulk CD8+ T cells], cell dose [dose level 2 (2 ×106 CAR+ T cells/kg vs. dose level 1 (2 ×105 CAR+ T cells/kg)], tumor burden [higher percentage of blasts in the bone marrow (BM) vs. lower percentage of blasts in the BM], and the conditioning regimen [Cy/Flu vs. Cy or Cy/etoposide) could contribute to in vivo persistence and expansion of CAR T cells (64).