Antibody-mediated CD8⁺ cell depletion is followed by increased CD8⁺ T-cell proliferation in the BM. Levels of T-cell proliferation were longitudinally assessed during antibody-mediated depletion of CD8⁺ cells in 3 healthy SMs and 3 healthy RMs. (A) Representative examples of the levels of CD8⁺ T cells before and after depletion in the PB and BM of a representative SM (left) and RM (right). (B) Average percentage of CD8⁺Ki-67⁺ T cells in the BM and PB before and at different time points after CD8 depletion in SMs (left) and RMs (right). (C) Average percentage of CD4⁺Ki-67⁺ T cells in the BM and PB before and at different time points after CD8 depletion in SMs (left) and RMs (right). The dotted lines in panels B and C indicated the timing of anti-CD8 monoclonal antibody administrations. Because of the extremely low level of CD8⁺ T cells, it was not possible to analyze their levels of Ki-67 expression at day 0 in both SMs and RMs.