Fig. 5 |. Early cellular senescence and loss of angiogenesis capacity in iPSC-derived aging endothelia is reversed by silencing CXCL9.

a, Pathway enrichment analysis and tube network formation of Scramble versus CXCL9-KD were analyzed. hiPSCs infected with lentivirus carrying nonsense-sequence shRNA (Scramble) and hiPSCs infected with lentivirus carrying sequence-specific shRNA to knockdown expression of CXCL9 (CXCL9-KD) were both induced to ECs (Methods). RNA-seq analysis was conducted on cells at passage 0, 2, 4, 6 and 8 for both conditions. CXCL9 messenger RNA in Scramble was highly upregulated as early as passage 4, whereas CXCL9 mRNA expression in CXCL9-KD did not significantly change with in vitro cellular aging. b, Pathway enrichment comparing Scramble at passage 0 and passage 8. Upregulated inflammatory pathways and downregulated proliferation pathways are depicted (P8 versus P0). c, Comparing Scramble at P8 with CXCL9-KD at P8 shows that silencing of CXCL9 leads to a complete reversal of the early EC senescence phenotype. An example of inflammatory pathway (IFN-γ) and an example of proliferation pathway (E2F targets) is shown in d. d, Relative expression of genes in the hallmark pathways for Scramble at passage 0, 2, 4, 6 and 8 (S0, S2, S4, S6 and S8) are shown. e, Example of inflammatory pathway (IFN-γ) and an example of proliferation pathway (E2F targets) for CXCL9-KD at passage 0, 2, 4, 6 and 8 (KD0, KD2, KD4, KD6 and KD8) are shown. ***P < 0.001; **P < 0.01; *P < 0.05.