Figure 4.

Activation and Killing by T Cells Is Selective for iPSC-β

(A) Experimental design: PBMCs co-cultured with autologous iPSC-derived cells.

(B, C, and F) CD25 or CD69 expression shown as MFI.

(B) PBMCs (gated on CD3⁺, CD4⁺, and CD8⁺ populations) co-cultured for 48 h with autologous iPSC-β (purple) or iPSC-α (red). (n = 3 T1D and n = 1 ND donor, n = 3 differentiation batches per donor line). T1D¹, T1D², and T1D³ were pooled together.

(C) Donor-matched PBMCs (CD3⁺ gated) (n = 1 T1D, n = 3 differentiation batches per donor line) co-cultured for 48 h with autologous iPSC-β (purple) or iPSC-cardiomyocytes (orange).

(D) Percentage of live iPSC-β (C-peptide⁺/glucagon⁻) or iPSC-α (C-peptide⁻/glucagon⁺) from iPSC-β or iPSC-α differentiations, respectively (n = 3 T1D donors, n = 3 differentiation batches per donor line). T1D¹, T1D², and T1D³ were pooled together.

(F) Representative flow cytometry histograms after 48 h of co-culture. Dashed histogram represents the control (untreated target cells).

(E) Percentage of apoptotic (apopxin⁺) iPSC-β (CD49a⁺/CD26⁻) or iPSC-α (CD49a⁻/CD26⁺) from iPSC-β or iPSC-α differentiations (n = 1 T1D iPSC donor, n = 3 differentiation batches per donor line).

(G) Unmatched PBMCs (CD3⁺ gated cells) co-cultured for 48 h with iPSC-α (n = 3 T1D donors, n = 3 differentiation batches per donor line). T1D¹, T1D², and T1D³ were pooled together.

(H) Donor-matched PBMCs (gated on CD3⁺, CD4⁺, and CD8⁺ populations) co-cultured for 48 h with autologous enriched iPSC-β or iPSC-α.

Data are means ± SEMs, 2-way ANOVA. ^∗p < 0.05, ^∗∗p < 0.005, ^∗∗∗p < 0.0005, and ^∗∗∗∗p < 0.0001; ns, non-significant. See also Figure S4.