In vivo fate mapping by TCR clonotyping uncovers the differentiation landscapes of T_N after transplant. (A) Graphic representation of the distribution within day 30 memory T-cell subsets of the TCRB sequences harbored by a given T-cell subset from LP. Numbers in donut graphs indicate the average percentages, from the 3 patients analyzed, of TCRB sequences retrieved in the indicated memory subsets 30 days after HSCT. (B) Quantification of the expansion ability of single-cell progenies of T lymphocytes with a given phenotype within LP, independent of the memory T-cell subset in which they were retrieved at day 30 post-HSCT. Expansion is measured as fold change of TCRB sequence count at day 30 relative to LP from a representative patient (UPN#12). (C) Circos plot¹⁶  graphically summarizes the distribution of TCRB sequences originally harbored by LP-T_N in a representative patient (UPN#12) of the 3 analyzed. LP-T_N sequences are depicted in the bottom part of the circle, identified by the green band. From each LP-T_N-derived TCRB sequence departs a ribbon connecting it to 1 or more memory subsets at day 30 post-HSCT. Each day 30 memory subset is denoted by a colored band (red for T_SCM, orange for T_CM, and blue for T_EM/EFF). Ribbon thickness is proportional to the TCRB sequence count of the given clonotype at day 30 post-HSCT. (D) Left pie chart shows the distribution at day 30 after transplant of the TCRB sequences originally harbored by LP-T_N. Numbers in the pie indicate the average percentages from the 3 patients analyzed; right chart zooms on the fraction of clonotypes that were found shared among 2 or more subsets at day 30 post-HSCT and depicts the mean distribution of all combinations retrieved. (E) Spearman correlation heat map representing the contribution of individual LP-T_N-derived clonotypes (row) to the repertoire of T_SCM, T_CM, and T_EM/EFF subsets at day 30 post-HSCT (columns). The analysis is performed to LP-T_N TCRB sequences that are shared by at least 2 memory T-cell subsets at day 30 post-HSCT. (F) Box plots quantify the expansion, measured as count fold change relative to LP, of LP-T_N TCRB sequences that were retrieved in memory T-cell subsets at day 30 post-HSCT. (G) Model scheme of a proposed branched diversification pathway from T_N to T_SCM, T_CM, and T_EM/EFF subsets on in vivo transfer after HSCT.