CD4 and acute lymphoblastic leukemia: Finally, in the phase-3 trial leading to the approval of blinatumomab in relapsed/refractory Bcp-ALL, the percentage of CD3+ T-cells measured at baseline had a significant impact on MRD-response to blinatumumab and greater values of both CD4+ or CD8+ T-cells at baseline predicted higher rates of hematological remission (18).