Specific transcriptional profile of BCMA iPSC-HPCs that differentiate into antigen-specific CD8⁺ memory T cells. (A) Principal component analysis of the top 1000 highly expressed genes showing the transcriptional variance (PC1 vs PC2) within or across iPSC-derived HPCs that differentiate into different cell lineages or primary HPCs isolated from the blood. (B) Hierarchical cluster analyses demonstrating 4 distinct clusters of variably expressed genes across the data set (upregulated genes = red and downregulated genes = blue). Clusters 1 and 4: upregulated (cluster 1) or downregulated (cluster 4) genes in iPSC-HPCs compared with primary HPCs from the blood, Clusters 2 and 3: downregulated (cluster 2) or upregulated (cluster 3) genes in iPSC-HPC (CD8⁺ T cells) compared with iPSC-HPC (CD3⁻ lymphocytes) and iPSC-HPC (nonlymphocytes). Nine samples evaluated; samples 1 and 2: iPSC-HPC (CD8⁺ T cells), samples 3 and 4: iPSC-HPC (CD3⁻ lymphocytes), samples 5 and 6: iPSC-HPC (nonlymphocytes), and samples 7, 8, and 9: primary HPCs from the blood. (C) Summary of differential gene expression profiles reported as the total number of upregulated (log fold-change > 2) or downregulated (log fold-change <−2) genes in iPSC-HPC (CD8⁺ T cells) compared with in iPSC-HPC (CD3⁻ lymphocytes), iPSC-HPC (nonlymphocytes), or primary HPCs from the blood. (D) Tables: summary of upregulated or downregulated genes in iPSC-HPC (CD8⁺ T cells) and their specific role in CD8⁺ T-cell lineage development. Volcano plots: significantly upregulated or downregulated genes in iPSC-HPC (CD8⁺ T cells) compared with (i) iPSC-HPC (CD3⁻ lymphocytes), (ii) iPSC-HPC (nonlymphocytes) or (iii) primary HPCs from the blood. Lym, lymphocytes.