Figure 1. Patterns of lymphocyte reconstitution and regulatory T cell-to-CD8⁺ effector ratio in MM patients after ASCT.

(A) Absolute lymphocyte count (ALC) was calculated before high-dose melphalan conditioning, on the day of stem cell infusion, and after ASCT on days +12, 30, 60, and 90. Dotted line indicates lower limit of normal ALC. (B-F) PBMCs were analyzed by flow cytometry for each lymphocyte subpopulation before (pre; 1-7 days before melphalan) and at the indicated time points after ASCT. (B) Total T cells: CD3⁺ (○) cells are plotted against the LEFT Y axis. CD4⁺ (□) and CD8⁺ (Δ) T cells are plotted against the RIGHT Y axis. (C) CD4⁺ T cells: naïve (CD45RA⁺; ○) and memory (CD45RO⁺; □). (D) CD8⁺ T cells: naïve (CCR7⁺CD45RO^neg; ○), central memory (CCR7⁺CD45RO⁺; Δ), effector memory (CCR7^negCD45RO⁺; ■), and effector (CCR7^negCD45RO^neg; □). (E) B cells (CD19⁺; ○), NK cells (CD3^negCD56⁺CD16^neg and CD3^negCD56^dimCD16⁺; □, and plasmacytoid dendritic cells (pDC; CD123⁺DR⁺CD11c^neg; ●). (F) Regulatory T cell (Treg; CD3⁺CD4⁺CD25^bright CD127^neg) to CD3⁺CD8⁺CD25⁺ effector T cell ratios. For all panels (A-F), pooled data (mean ± SD) from 55 patients are shown. *P < .05 and ***P < .001.