Effect of the combination RG7388 and temsirolimus on human lymphocyte reconstitution in humanized NSG mice. A, Schema of drug treatment and peripheral blood (PB) and bone marrow (BM) collections. B, Mice with greater than 40% human CD45+ reconstitution at 7 weeks of age were selected. Six mice received vehicle controls, and six received the combination therapy. Percentages of human CD45+(hCD45) and mouse CD45+(mCD45) cells were assessed in the PB at time 0 and at the indicated time points, and in the BM at day 35 after treatment. Percentages of hCD45 are shown for each individual mouse at the different time points. C, Mean values ± SD of hCD45% in control and treated mice at the indicated time points after treatment. Percentages of hCD45 significantly drop at day 21 after treatment in mice treated with the combination therapy compared with controls. However, they are robustly restored at day 35 after treatment. D, No differences in percentages of hCD45 in PB were detected at day 35 after treatment between controls and treated mice.