Figure 3: Immune response elicited by iECs resembled the one by AECs.

Lymphocytic infiltration in cellular grafts was measured by FACS. (a) The iPSC graft displayed marked increase in lymphocytes compared with iEC, AEC and sham grafts. (b) Percentage (left) and absolute counts (right) of infiltrating CD3⁺ T cells was reduced in terminally differentiated iECs and AECs. (c) Helper CD4⁺ T cells were predominant among the T cells infiltrating iEC and AEC grafts. By contrast, cytotoxic (CD8⁺) T cells were found at a much higher percentage in iPSC grafts. Percentages of CD4⁺ and CD8⁺ cells were calculated from CD3⁺ parental gate. (d) Percentage of FoxP3 expression in CD4⁺ T cells demonstrating higher prevalence in iPSC compared to AEC grafts. (e) Fold-change in gene expression relative to sham grafts demonstrating the differences in immunological milieu intragrafts, with iPSCs having significantly higher mRNA expression of Granzyme-B and Perforin factors compared with iEC and AEC grafts. Data are representative of mean±s.e.m. of eight animals per group from three experiments. Significance of differences between series of results was assessed using analysis of variance with Tukey for multiple comparisons. *P<0.05, **P<0.01, ***P<0.001, ****P<0.0001.